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Sample records for argentine dairy heifers

  1. Intramammary infections during the periparturient period in Argentine dairy heifers Infecciones intramamarias durante el periparto en vaquillonas en Argentina

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    L. F. Calvinho

    2007-06-01

    Full Text Available Prevalence of intramammary infections at prepartum and postpartum in primigravid heifers from five dairy herds located in the central dairy area of Argentina was determined. Mammary secretion samples from 140 heifers (560 mammary quarters were obtained 14 days prior to the expected calving day and within 7 days after parturition and subjected to bacteriological analysis. No clinical mastitis cases were detected during the study. The number of infected heifers in at least one mammary quarter at pre and postpartum was 87 (62.2% and 53 (37.8%, respectively. The most prevalent mastitis pathogens at prepartum among samples yielding a positive bacteriological culture were coagulasenegative staphylococci (69.07%, Staphylococcus aureus (12.71% and Streptococcus uberis (4.42%. A decrease on isolation frequency of coagulase-negative staphylococci (53.41% and S. uberis (2.27% was observed at postpartum, while that of S. aureus showed an increase (21.59%. Presence of intramammary infections appeared to be associated with some management conditions. These results highlighted the need to improve diagnosis and control measures in replacement heifers.Se determinó la prevalencia al preparto y posparto de infecciones intramamarias causadas por organismos patógenos de mastitis en vaquillonas primíparas de cinco establecimientos lecheros ubicados en la cuenca central santafesina. Se tomaron muestras de secreción mamaria de 140 vaquillonas (560 cuartos mamarios aproximadamente 14 días antes de la fecha probable de parto y dentro de los 7 días posparto, y se procesaron bacteriológicamente. No se detectaron casos de mastitis clínicas durante el estudio. El número de vaquillonas infectadas en al menos un cuarto mamario al preparto y posparto fue de 87 (62,2% y 53 (37,8%, respectivamente. Los organismos patógenos más prevalentes al preparto entre las muestras con cultivo bacteriológico positivo fueron estafilococos coagulasa negativos (69,07%, Staphylococcus

  2. Potential for sorghum forages for dairy heifers in the midwest

    Science.gov (United States)

    Dairy heifers have lower dietary energy needs than lactating cows (63-65% TDN for 6-12 month old heifers; 58-60% TDN for >12 month old heifers), but forage-based diets containing significant amounts of corn silage often exceed the needs of pregnant heifers. Use of low-energy forages to decrease ener...

  3. Record keeping and economics of dairy heifers.

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    Bach, Alex; Ahedo, José

    2008-03-01

    Calves represent the future of the dairy enterprise. Like in any other business, a careful allocation of resources and planning is needed to ensure the production of a new line, new products, and so forth. This article describes the most important objectives while rearing heifers, reviews the main aspects of implementing a record system, and provides examples of some of the decisions that can be taken by analyzing records.

  4. Improved grazing activity of dairy heifers in shaded tropical grasslands

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    Andréia Cristina Tavares de Mello

    Full Text Available ABSTRACT: Trees in the production systems can effectively reduce hot weather-induced stress in the Brazilian Midwest. High temperatures cause changes in animals daily routine, and trees into pastures can promote benefits. The aim of this research was to evaluate the behavior of dairy heifers in silvopastoral systems in the state of Mato Grosso, Brazil. A herd of 24 crossbreed heifers (3/4 and 7/8 Holstein/Zebu, 350kg average weight, was evaluated over three seasons. Piatã grass was managed under three shade levels: full-sun, moderate-shade, and intensive-shade provided by 10 to 12m high Eucalyptus trees. Behavior data were collected every 15 minutes from 8:30h to 16h. Shade availability significantly impacted heifer behavior, mainly affecting grazing frequency and time during the hottest hours. Grazing behavior was affected by shade levels during the different seasons. Heifers showed preferred grazing times. Heifers in the intensive-shade system visited shady areas during the hottest hours throughout the seasons. Heifers in the full sun-system avoided grazing during the warmer times, ceasing feeding activities. Our results from the Brazilian Midwest showed that shade availability causes breed heifers to change their daily routine.

  5. Utility of alfalfa stemlage for feeding dairy heifers

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    Dairy heifers are typically offered high-forage diets to control weight gains; however, these forage-based diets often contain significant portions of corn silage or other high-quality forages with low fiber concentrations. Inadequate concentrations of dietary fiber can lead to greater feed and ener...

  6. Event-time analysis of reproductive traits in dairy heifers.

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    Vargas, B.; Lende, van der T.; Baaijen, M.; Arendonk, van J.A.M.

    1998-01-01

    Data on the reproductive traits of dairy heifers were analyzed using event-time techniques. Traits analyzed were age at first calving (n = 4631), days to first breeding, and days open (n = 1992) during the first lactation. A proportional hazard model was used that included fixed effects of herd-year

  7. Characterization of transfer of passive immunity in dairy heifer calves.

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    Jorge Alberto Elizondo-Salazar

    2015-06-01

    Full Text Available The objective of this study was to determine the transfer of passive immunity in dairy heifer calves in Costa Rica. The data presented correspond to total serum protein (TSP measurements obtained in the period between 2010 and 2013, between August and November in 50 dairy farms. A total of 2500 heifer calves were sampled. Dams breed were classified into Holstein, Jersey, Holstein.Jersey crosses and others. For the purpose of this study, failure of passive immunity was considered when TSP concentration was less than 5.5 g/dl. TSP concentration ranged from 2.0 to 10.0, with an overall mean of 5.9 g/dl. Of all the calves evaluated, 38.8% presented failure of passive transfer of immunity. Calves born to Jersey and Holstein×Jersey crosses had significantly higher TSP concentrations than calves born to Holstein and other breeds. When considering calving of the dam, there were no significant differences on TSP concentration; however, offsprings born to first lactation heifers showed the lowest percentage of animals with failure of passive transfer of immunity. There were significant differences on TSP concentrations (P<0,05 between calves that were allowed to suckle their dams and calves that were given colostrum by bottle. Failure of passive transfer of immunity was higher when calves stayed with their dams (44% vs. 33%.

  8. Pathogen group specific risk factors at herd, heifer and quarter levels for intramammary infections in early lactating dairy heifers.

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    Piepers, S; Peeters, K; Opsomer, G; Barkema, H W; Frankena, K; De Vliegher, S

    2011-05-01

    Risk factors for intramammary infections caused by coagulase-negative staphylococci, contagious major pathogens and environmental major pathogens in early lactating heifers were evaluated at the herd, heifer and quarter levels. In total, 764 quarters of 191 dairy heifers in 20 randomly selected farms in Flanders (Belgium) were sampled. Quarter milk samples were collected between 1 and 4 days in milk and between 5 and 8 days in milk for bacteriological culture. Data were analyzed using multivariable, multilevel logistic regression analysis. Higher average herd milk somatic cell count (>200,000 cells/mL), not having an effective fly control strategy, contact with lactating cows prior to calving and moderate to severe udder edema prior to calving increased the odds of intramammary infections caused by contagious major pathogens. Poor heifer hygiene and lack of mineral/vitamin supplementation prior to calving were risk factors for intramammary infection caused by environmental major pathogens. Teat apex colonization with coagulase-negative staphylococci prior to calving seemed to protect quarters against intramammary infections caused by major pathogens. Poor heifer hygiene before calving, a non-clipped udder and not practicing of teat dipping prior to calving increased the odds of intramammary infection with coagulase-negative staphylococci. Although management is important in the prevention and control of intramammary infections in early lactating heifers, most variation in the prevalence of intramammary infections resided at the heifer and quarter levels, indicating that the susceptibility for intramammary infections around calving is mainly determined by heifer and quarter characteristics.

  9. Effect of diet energy level and genomic residual feed intake on dairy heifer performance

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    The objective of this study was to determine the growth, feed intake, and feed efficiency of dairy heifers with different genomically predicted residual feed intakes (RFI), and offered diets differing in energy density. Post-bred Holstein heifers (N=128; ages 14-20 months) were blocked by initial we...

  10. Effect of limit feeding and genomic residual feed intake on bred dairy heifer performance

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    The objective of this study was to evaluate growth, intake, and feed efficiency of dairy heifers with different predicted genomic residual feed intakes as lactating cows (RFI) offered diets for ad-libitum intake or limit-fed. Post-bred Holstein heifers (128, ages 14-20 months), were blocked by initi...

  11. Milk yield and reproductive performance of dairy heifers and cows supplemented with polyunsaturated fatty acids

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    Félix Gonzalez

    2015-04-01

    Full Text Available The objective of this work was to determine productive and fertility responses of Holstein-Friesian heifers and cows to supplementation with extruded linseed and soybean as sources of polyunsaturated fatty acids (PUFAs. Supplementation had a positive effect on profitability, with significant increases in milk yield in supplemented cows, but not in heifers. Treatments had no effect on milk fat content, but higher milk protein contents were observed with supplementation. A higher conception rate was found for supplemented heifers, but not for cows. Fat sources containing PUFAs are recommended for dairy cattle supplementation, since they improve fertility in heifers and milk yield in cows.

  12. Effects of flooring and restricted freestall access on behavior and claw health of dairy heifers

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    Ouweltjes, W.; Werf, van der J.T.N.; Frankena, K.; Leeuwen, van J.L.

    2011-01-01

    Claw health, locomotion, feed intake, milk yield, body weight, activity, and lying and standing behavior of dairy heifers were monitored in a single dairy herd during the first 3 mo after calving. During the first 8 wk after calving, 2 treatments were applied: restricted freestall access by closing

  13. Duration of estrus induced after GnRH-PGF2alpha protocol in dairy heifer.

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    Yoshida, Chikako; Yusuf, Muhammad; Nakao, Toshihiko

    2009-12-01

    Estrous expressions in dairy cows have been shortened and weakened. Dairy heifers, on the other hand, may not have had such changes in estrous signs as observed in cows, since they have less stresses than cows. The aim of this study was to describe the duration of estrus in a herd of dairy heifers. A total of 56 Holstein Friesian heifers estrus was synchronized using two different hormonal protocols. They were checked for primary and secondary estrous signs with the help of heat detection devices for 48 h at an interval of 4 h starting at 16.00 hour, one day after PGF(2alpha) treatment. Onset and end of standing estrus during 48 h observation period was recorded in 35 of the 44 heifers coming into estrus within 5 days after PGF(2alpha) treatment during the observation period. The duration of standing estrus on the average (+/-SD) was 9.7 +/- 5.3 h. Percentage of heifers with standing estrus longer than 12 h was 40%, and 53% showed standing estrus only for 4-8 h. It is indicated that duration of estrus in dairy heifers has been shortened recently.

  14. Increased Fecal Ethanol and Methanol Concentration in Dairy Heifers after Grazing

    OpenAIRE

    Sato, H.; Kurosawa, T.

    2011-01-01

    To clarify fermentative alterations in the large intestine (hindgut) during grazing, fecal alcohol and volatile fatty acids (VFAs) concentrations were evaluated in 30 dairy heifers. The heifers were kept in pasture growing mixed grass herbage from spring (mid May) until October, and their rectal feces were collected periodically. Concentrations of ethanol, methanol and isopropanol were increased in runny feces at early stage of grazing, but gradually decreased thereafter, despite the fact tha...

  15. 转基因奶牛与普通奶牛超数排卵效果的比较分析%Comparative Analysis of Superovulation Responses in Transgenic Dairy Heifers and Ordinary Dairy Heifers

    Institute of Scientific and Technical Information of China (English)

    朱玉林; 薛建华; 吕小青; 李艳华; 孙凤俊; 杨超; 戴蕴平; 王彦平; 赵凤茹; 丁方荣

    2014-01-01

    In this study, we compared the superovulation responses between transgenic dairy heifers and ordinary dairy heifers. Of the transgenic dairy heifers, 16 out of 20 responded to superovulation treatment. On average, the total number of embryos/ova and transferable embryos, unfertilized ova, degenerated embryos produced in transgenic dairy heifers were 6.15±4.43(mean±SEM) and 3.94±2.62, 1.50±2.19, 0.69±0.78, respectively. Of the ordinary dairy heifers, 17 out of 20 responded to superovulation treatment. On average, the total number of embryos/ova and transferable embryos, unfertilized ova, degenerated embryos produced in transgenic dairy heifers were 8.65±5.70 and 4.18±3.11, 1.47±1.12, 3.00±4.24, respectively. There was no signiifcant difference between transgenic dairy heifers and ordinary dairy heifers in the total number of embryos/ova and transferable embryos, unfertilized ova(P>0.05).There was a decrease in the number of degenerated embryos in transgenic dairy heifers(P0.05),转基因奶牛的退化胚胎数显著低于普通奶牛(P<0.05)。本试验结果说明转入改变乳成分的外源基因不影响奶牛的超数排卵效果。

  16. Effects of straw processing and pen stocking density on holstein dairy heifers: ii) behavior and hygiene

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    The effects of pen-stocking density and straw processing on the daily behavior traits and hygiene of Holstein dairy heifers housed in a freestall system are not understood. Our objective was to evaluate these factors in a trial with a 2 × 3 factorial arrangement of straw-processing (GOOD or POOR) an...

  17. Effects of straw processing and pen stocking density on holstein dairy heifers: i) growth and sorting characteristics

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    Our objectives were to evaluate effects of pen-stocking density (freestall housing) and straw processing on heifer growth performance and feedbunk sorting behaviors by Holstein dairy heifers. A 2 × 3 factorial arrangement of straw-processing (GOOD or POOR) and pen-stocking-density [100 (CONTROL), 12...

  18. Effect of diet energy level and genomic residual feed intake on pre-bred dairy heifer feed intake and growth

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    The objective of this study was to determine the growth, feed intake, and feed efficiency of pre-bred dairy heifers with different predicted genomic residual feed intakes as lactating cows (RFI), and offered diets with different energy levels. Pre-bred heifers (128, ages 4-9 months) were blocked by ...

  19. Feed delivery method affects the learning of feeding and competitive behavior in dairy heifers.

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    Greter, A M; Leslie, K E; Mason, G J; McBride, B W; DeVries, T J

    2010-08-01

    The objective of this study was to determine how different feeding methods may affect the learning of feeding, sorting, and competitive behavior of growing dairy heifers. We hypothesized that heifers previously fed a total mixed ration (TMR) would distribute their feeding time more evenly throughout the day, sort the new ration less, compete less for feed, maintain a more solid fecal consistency, and continue to grow rapidly compared with heifers previously fed a top-dressed ration (TDR). Thirty-two Holstein heifers (237.2+/-21.9 d of age) were divided into 8 groups of 4 and exposed to 1 of 2 treatments for 13 wk: 1) TMR or 2) TDR, with each containing 65% grass/alfalfa haylage and 35% textured concentrate on a dry matter (DM) basis. Following this feeding period, all heifers were switched to an unfamiliar TMR containing 56.1% grass/alfalfa haylage, 21.0% corn silage, 21.0% high-moisture corn, and 1.9% mineral supplement (DM basis) for 7 wk. Group DM intakes were recorded daily throughout the experiment. Feeding behavior, recorded using time-lapse video, and sorting behavior were measured for 7 d during wk 1, 4, and 7 after the dietary change. Feeding competition was measured on d 2, 4, and 6 of each recording week. Sorting activity was determined through particle size analysis of the fresh feed and orts. The particle size separator separated feed into 4 fractions (long, medium, short, and fine). Sorting of each fraction was calculated as actual intake expressed as a percentage of predicted intake. Animals were scored for fecal consistency twice weekly, using a scale from 1 (liquid) to 4 (solid). Heifers were weighed every 2 wk. Neither DM intake (9.0 kg/d) nor average daily gain (1.2 kg/d) differed between treatments. Sorting also did not differ between treatments. Heifers tended to spend more time feeding if they had previously been fed a TDR (198.8 vs. 186.8 min/d). As they had done before the dietary change, heifers previously fed the TDR spent more time at the

  20. The effect of Bovine Growth Hormone on Growth, Carcass Composition and Meat Quality of Dairy Heifers

    DEFF Research Database (Denmark)

    Vestergaard, Mogens; Sejrsen, Kristen; Foldager, John

    1993-01-01

    Our objective was to examine the effects of bovine growth hormone (bGH) on growth, carcass composition and meat quality of dairy heifers. Nine monozygotic twin pairs of Friesian or Red Danish cattle were used, and pair-fed diet consisting of grass silage, barley and soybean meal. Within each pair......, one animal was given daily subcutaneous injections of 20 IU of pituitary-derived bGH (15-20 mg), while the other animal was injected with saline (excipient). Treatments started at 179±2 kg body weight and lasted for 15.6 weeks. At slaughter, carcass composition and meat quality were analyzed. b...... fat by 13% (P meat quality assessed by objective as well as subjective methods was unaffected by bGH treatment. In summary, bGH treatment of dairy heifers around puberty stimulated growth and reduced carcass fattening...

  1. Expected net present value of pure and mixed sexed semen artificial insemination strategies in dairy heifers.

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    Olynk, N J; Wolf, C A

    2007-05-01

    Sexed semen has been a long-anticipated tool for dairy farmers to obtain more heifer calves, but challenges exist for integrating sexed semen into commercial dairy farm reproduction programs. The decreased conception rates (CR) experienced with sexed semen make virgin heifers better suited for insemination with sexed semen than lactating dairy cows. This research sought to identify when various sexed semen breeding strategies provided higher expected net present value (NPV) than conventional artificial insemination (AI) breeding schemes, indicating which breeding scheme is advisable under various scenarios. Budgets were developed to calculate the expected NPV of various AI breeding strategies incorporating conventional (non-sexed) and sexed semen. In the base budgets, heifer and bull calf values were held constant at $500 and $110, respectively. The percentage of heifers expected to be born after breeding with conventional and sexed semen used was 49.2 and 90%, respectively. Breeding costs per AI were held constant at $15.00 per AI for conventional semen and $45.00 per AI for sexed semen of approximately the same genetic value. Conventional semen CR of 58 and 65% were used, and an AI submission rate was set at 100%. Breeding strategies with sexed semen were assessed for breakeven heifer calf values and sexed semen costs to obtain a NPV equal to that achieved with conventional semen. Breakeven heifer calf values for pure sexed semen strategies with a constant 58 and 65% base CR in which sexed semen achieved 53% of the base CR are $732.11 and $664.26, respectively. Breakeven sexed semen costs per AI of $17.16 and $22.39, compared with $45.00 per AI, were obtained to obtain a NPV equal to that obtained with pure conventional semen for base CR of 58 and 65%, respectively. The strategy employing purely sexed semen, with base CR of both 58 and 65%, yielded a lower NPV than purely conventional semen in all but the best-case scenario in which sexed semen provides 90% of

  2. Feeding & Management of Dairy Calves & Heifers. Teacher's Guide.

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    Bjoraker, Walt

    This guide is designed to assist postsecondary and secondary teachers of agriculture in their use of the University of Wisconsin bulletin "Raising Dairy Replacements" in their dairy science instructional program. Eight lessons are provided in this unit: breeding decisions, management of cows from breeding to calving, care at calving time, the…

  3. Tactile stimulation of dairy heifers: effects on behavior and milk production after calving

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    N. R. M. Néri

    2016-09-01

    Full Text Available The positive management of primiparous heifers before calving through tactile stimulation may have beneficial effects on behavior during routine milking. The objective of this study was to evaluate the use of tactile stimulation in dairy heifers and its effects on behavior and milk production after calving. Ten primiparous Holstein heifers were used. Half the group received training with tactile stimulation of all body regions, while the other group did not receive stimulation (control group. The training period was divided into three phases: early, days 1 to 6 of training; intermediate: days 7 to 12, and final, days 13 to 23. During training, movement and displacement scores were obtained over a period of 5 minutes. Physiological parameters were also recorded [respiratory rate (FR and minimum eye temperature (ETmin measured with a thermal imaging camera]. After calving, the heifers were submitted to first milking when the evaluations were started for the first 10 days of milking (20 consecutive milkings. The behavior of the animals was evaluated by attributing a reactivity score of 1 (desirable behaviors or 2 (undesirable behaviors: entry into the pen, teat disinfection, milking one or two jets of milk for mastitis testing, attachment of teat cups, and removal of milk, as well as the amount of milk produced. Mean ETmin and FR decreased over the training period. A significant difference was observed for displacement score (P=0.019, with a reduction in displacement from the early to the final period (from 60.0% to 25.7%. During the attachment of teat cups, stimulated heifers were less reactive (P=0.002, characterized by a lower frequency of undesirable behaviors (12.0%, than unstimulated heifers (30.2%. The average milk yield during the first 60 days of lactation was higher for the group of stimulated heifers (Ln y=2.20–0.0102t+0.331lnt, R2=0.76 compared to unstimulated heifers (Ln y=1.54–0.0191x+0.578lnx, R2=0.79, with this difference being

  4. Fall-grown oat to extend the fall grazing season for replacement dairy heifers.

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    Coblentz, W K; Brink, G E; Hoffman, P C; Esser, N M; Bertram, M G

    2014-03-01

    Our objective was to assess the pasture productivity and forage characteristics of 2 fall-grown oat (Avena sativa L.) cultivars, specifically for extending the grazing season and reducing reliance on harvested forages by replacement dairy heifers. A total of 160 gravid Holstein heifers (80 heifers/yr) were stratified by weight, and assigned to 1 of 10 identical research pens (8 heifers/pen). Initial body weights were 480 ± 43.5 kg in 2011 and 509 ± 39.4 kg in 2012. During both years of the trial, four 1.0-ha pasture replicates were seeded in August with Ogle oat (Schumitsch Seed Inc., Antigo, WI), and 4 separate, but similarly configured, pasture replicates were seeded with Forage Plus oat (Kratz Farms, Slinger, WI). Heifer groups were maintained as units, assigned to specific pastures, and then allowed to graze fall-oat pastures for 6h daily before returning to the barn, where they were offered a forage-based basal total mixed ration. Two heifer groups were retained in confinement (without grazing) as controls and offered the identical total mixed ration as pasture groups. During 2011, available forage mass increased with strong linear and quadratic effects for both cultivars, peaking at almost 9 Mg/ha on October 31. In contrast, forage mass was not affected by evaluation date in 2012, remaining ≤ 2,639 kg/ha across all dates because of droughty climatic conditions. During 2012, Ogle exhibited greater forage mass than Forage Plus across all sampling dates (2,678 vs. 1,856 kg/ha), largely because of its more rapid maturation rate and greater canopy height. Estimates of energy density for oat forage ranged from 59.6 to 69.1% during 2011, and ranged narrowly from 68.4 to 70.4% during 2012. For 2011, responses for both cultivars had strong quadratic character, in which the most energy-dense forages occurred in mid November, largely due to accumulation of water-soluble carbohydrates that reached maximum concentrations of 18.2 and 15.1% for Forage Plus and Ogle

  5. First results from insemination with sex-sorted semen in dairy heifers in Macedonia

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    Ljupche Kochoski

    2015-03-01

    Full Text Available Science has been searching for a long time for a reliable method for controlling the sex of mammalian offspring. Recently, the application of specific modern cellular methodologies has led to the development of a flow cytometric system capable of differentiating and separating living X- and Y-chromosome-bearing sperm cells in amounts suitable for AI and therefore, commercialization of this sexing technology. The aim of this work was to present the first results of heifers that introduce bovine AI with sex sorted semen, for the first time in Macedonia. Insemination with sex sorted cryopreserved semen (2x106 spermatozoa per dose imported from the USA was done at two dairy farms in ZK Pelagonija. In total, 74 heifers (Holstein Friesian were inseminated. Inseminations were carried out in a timely manner following a modified OvSynch protocol. During the insemination, the sperm was deposited into the uterine horn ipsi lateral to the ovary where a follicle larger than 1.6 cm was detected by means of transrectal ultrasound examination. Pregnancy was checked by ultrasound on day 30 after the insemination. Overall, the average pregnancy rate in both farms was 43,24% (40,54% and 45,95%, for farm 1 and farm 2, respectively. All pregnant heifers delivered their calves following a normal gestation length (274,3 days in average and of the 32 born calves, 30 (93,75% were female. In conclusion, since the first results from inseminations with sex-sorted semen in dairy heifers in Macedonia are very promising, the introduction of this technique may bring much benefit to the local dairy sector. Average pregnancy rate seems similar with results obtained following ‘regular’ inseminations, notwithstanding the relatively low number of spermatozoa per insemination dose. Due to the latter, we however recommend inseminations only to be carried out by experienced technicians followinga TAI protocol and ultrasound examinations of the ovaries prior to insemination.

  6. Invited review: Mastitis in dairy heifers: nature of the disease, potential impact, prevention, and control.

    Science.gov (United States)

    De Vliegher, S; Fox, L K; Piepers, S; McDougall, S; Barkema, H W

    2012-03-01

    Heifer mastitis is a disease that potentially threatens production and udder health in the first and subsequent lactations. In general, coagulase-negative staphylococci (CNS) are the predominant cause of intramammary infection and subclinical mastitis in heifers around parturition, whereas Staphylococcus aureus and environmental pathogens cause a minority of the cases. Clinical heifer mastitis is typically caused by the major pathogens. The variation in proportions of causative pathogens between studies, herds, and countries is considerable. The magnitude of the effect of heifer mastitis on an individual animal is influenced by the form of mastitis (clinical versus subclinical), the virulence of the causative pathogen(s) (major versus minor pathogens), the time of onset of infection relative to calving, cure or persistence of the infection when milk production has started, and the host's immunity. Intramammary infection in early lactation caused by CNS does not generally have a negative effect on subsequent productivity. At the herd level, the impact will depend on the prevalence and incidence of the disease, the nature of the problem (clinical, subclinical, nonfunctional quarters), the causative pathogens involved (major versus minor pathogens), the ability of the animals to cope with the disease, and the response of the dairy manager to control the disease through management changes. Specific recommendations to prevent and control mastitis in late gestation in periparturient heifers are not part of the current National Mastitis Council mastitis and prevention program. Control and prevention is currently based on avoidance of inter-sucking among young stock, fly control, optimal nutrition, and implementation of hygiene control and comfort measures, especially around calving. More risk factors for subclinical and clinical heifer mastitis have been identified (e.g., season, location of herd, stage of pregnancy) although they do not lend themselves to the development

  7. Lipid mobilisation and oxidative stress as metabolic adaptation processes in dairy heifers during transition period.

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    Turk, R; Podpečan, O; Mrkun, J; Kosec, M; Flegar-Meštrić, Z; Perkov, S; Starič, J; Robić, M; Belić, M; Zrimšek, P

    2013-10-01

    The objective of this study was to evaluate metabolic disorders and oxidative stress in dairy heifers during the transition period. Possible relationships between lipid mobilisation indicators and oxidative stress markers were investigated as well. Nineteen dairy heifers were included in the study. Blood samples were collected at the time of estrus synchronisation in heifers, at insemination, three weeks after insemination, one week before calving, at calving and 1, 2, 4 and 8 weeks postpartum. Common metabolic parameters, beta-hydroxybutyrate (BHB), free fatty acids (FFA), paraoxonase-1 (PON1) activity and total antioxidative status (TAS) were analysed. Around insemination, no significant difference was observed in the majority of tested parameters (P>0.05). However, the transition period markedly affected the concentration of triglycerides, total cholesterol, HDL-C, BHB, FFA, TAS and PON1activity. Positive correlations between PON1 activity and total cholesterol, HDL-C and triglycerides were noted but inverse correlations with FFA, BHB and bilirubin were found indicating that PON1 activity changed with lipid metabolism and was influenced by negative energy balance. These findings suggest that lipid mobilisation and oxidative stress are part of a complex metabolic adaptation to low energy balance which reaches equilibrium later in advanced lactation.

  8. Behavioral responses of dairy heifers confined to the evaporative cooling system

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    Gianni Aguiar da Silva

    2013-03-01

    Full Text Available The research aimed to evaluate the influence of evaporative cooling system (AECS on the behavioral variables of Holstein dairy heifers kept in confinement. Twelve heifers were used, divided into three treatments: 1 ventilation and fogging by AECS when the temperature reached 25°C at any humidity, 2 ventilation and fogging by AECS when the temperature reached 25°C with relative humidity less than or equal to 70% and, 3 without cooling system. The experimental design consisted of a latin rectangle repeated twice. The environmental variables (dry bulb temperature, black globe temperature and relative humidity were collected daily through dataloggers throughout the experiment. In behavioral analysis were observed postures (standing and lying, the activities of the animals and the places where they were in the pen, in 15 minute intervals. However, there was no difference in the behavioral variables of animals between treatments.

  9. Trainability of eliminative behaviour in dairy heifers using a secondary reinforcer

    DEFF Research Database (Denmark)

    Whistance, Lindsay Kay; Sinclair, Liam A.; Arney, David Richard

    2009-01-01

    Soiled bedding influences cleanliness and disease levels in dairy cows and there is no evidence of an inherent latrine behaviour in cattle. If cows were trained to use a concrete area of the housing system as a latrine, a cleaner bed could be maintained. Thirteen group-housed, 14-16-month-old...... (141) but four heifers with consistently longer lying bouts also showed more C → S before lying down (Mann-Whitney, P = 0.007). The present study is believed to be the first reported work to show that cattle can be trained to show an awareness of their own eliminative behaviour...

  10. Oregano Extract Added into the Diet of Dairy Heifers Changes Feeding Behavior and Concentrate Intake

    Directory of Open Access Journals (Sweden)

    Giovani Jacob Kolling

    2016-01-01

    Full Text Available This experiment aimed to describe the effects of Oregano extract (OE inclusion into the concentrate fed to dairy heifers on physiological parameters, feeding behavior, intake, and performance. Thirty-two Holstein heifers were randomly distributed into four treatments: C = control, without addition of OE; OE2.5 = 2.5 g; OE5.0 = 5.0 g and OE7.5 = 7.5 g of Oregano extract per heifer/day. Feeding behavior and concentrate intake were assessed individually every day and total dry matter intake (DMI was determined on the last week of the trial. Compared to control group, OE7.5 reduced by 32% the latency time to approach the feed bunk but increased by 6% the time spent eating the concentrate. Each inclusion of 2.5 grams of OE into the concentrate increased the occurrence of postingestive licking the feed bunk with abundant saliva production 1.2 times (P<0.01 and tended to increase the occurrence of sneeze events 1.2 times (P<0.10. No statistical difference was detected between treatments for total DMI, but concentrate DMI was 9% lower for OE7.5 when compared to control and OE2.5. The inclusion of 7.5 grams/day of OE causes small but negative effects in feeding behavior and concentrate intake, without change on total dry matter intake.

  11. Oregano Extract Added into the Diet of Dairy Heifers Changes Feeding Behavior and Concentrate Intake

    Science.gov (United States)

    Kolling, Giovani Jacob; Stumpf, Marcelo Tempel; da Cruz, Eduardo Augusto

    2016-01-01

    This experiment aimed to describe the effects of Oregano extract (OE) inclusion into the concentrate fed to dairy heifers on physiological parameters, feeding behavior, intake, and performance. Thirty-two Holstein heifers were randomly distributed into four treatments: C = control, without addition of OE; OE2.5 = 2.5 g; OE5.0 = 5.0 g and OE7.5 = 7.5 g of Oregano extract per heifer/day. Feeding behavior and concentrate intake were assessed individually every day and total dry matter intake (DMI) was determined on the last week of the trial. Compared to control group, OE7.5 reduced by 32% the latency time to approach the feed bunk but increased by 6% the time spent eating the concentrate. Each inclusion of 2.5 grams of OE into the concentrate increased the occurrence of postingestive licking the feed bunk with abundant saliva production 1.2 times (P < 0.01) and tended to increase the occurrence of sneeze events 1.2 times (P < 0.10). No statistical difference was detected between treatments for total DMI, but concentrate DMI was 9% lower for OE7.5 when compared to control and OE2.5. The inclusion of 7.5 grams/day of OE causes small but negative effects in feeding behavior and concentrate intake, without change on total dry matter intake. PMID:28116344

  12. Housing, Feeding and Management of Calves and Replacement Heifers in Swedish Dairy Herds

    Directory of Open Access Journals (Sweden)

    Liberg P

    2001-12-01

    Full Text Available A questionnaire was sent to 1500 randomly selected dairy herds in Sweden, asking for general information about the herds, including routines from birth to first calving and also routines at breeding, calving and during the grazing period. Fifty-eight percent of the questionnaires were returned. The preweaned calves were kept in individual calf pens in 68% and in group housing systems in 28% of the herds. Pens with slatted floors were the main housing system for replacement heifers from weaning to breeding, and tie stalls from breeding to first calving. Whole milk was used in 44% and milk replacements in 42% of the herds. The calves received, as a median, 2.5 litres of milk per meal and 2 meals per day. The median age at weaning was 8 weeks. Age was the single most common criteria used for deciding both weaning and breeding time. The median age when the heifers were first turned out to pasture was 6 months. Prophylactic anthelmintic treatment was used by 65% of the herds. The most common diet for replacement heifers before calving was a combination of grain, hay and silage.

  13. An advisory tool to improve management practices affecting calf and heifer welfare on dairy farms.

    Science.gov (United States)

    Vasseur, E; Rushen, J; de Passillé, A M; Lefebvre, D; Pellerin, D

    2010-09-01

    We developed an advisory tool addressing 10 critical areas of calf and heifer management, including calving management, care to newborn calves and painful procedures, colostrum management, cow-calf separation, calf feeding, weaning, calf housing, heifer feeding, heifer housing, and general monitoring. Targets and indicators for each critical area were validated by a panel of experts and maximum scores were assigned based on experts' opinions and reviews of scientific literature. The tool was tested on 28 Quebec dairy farms for feasibility and repeatability between 2 observers. Farmers were asked to test colostrum quality, measure blood IgG concentrations, and record health events. The on-farm evaluation included an interview on management practices and an evaluation of conditions in the barn. Scorings and recommendations were discussed with producers. The usefulness of our on-farm welfare tool was evaluated by the producers themselves during a final debriefing. We reached the main goals of a successful advisory tool of calf and heifer management to improve welfare on dairy farms. We respected the targeted time limit of a 3-h visit covering all aspects of our tool including data collection on management and environment, scoring, practical demonstration with producers, and debriefing. We had no problems collecting management- and environment-based data and had high repeatability of qualitative environment-based measures (kappa value>0.6). Our tool helped to detect problems and to discuss these problems with the producers; producers scored below 50% for some targets in calving management, care to newborn calves and painful procedures, colostrum management, and calf feeding. The targets were realistic so producers were not discouraged. All producers were convinced of the usefulness of our tool for identifying areas of calf and heifer management in need of improvement. They were also convinced of the usefulness of our tool as an advisory tool for technical advisors and

  14. Relationships between residual feed intake, average daily gain, and feeding behavior in growing dairy heifers.

    Science.gov (United States)

    Green, T C; Jago, J G; Macdonald, K A; Waghorn, G C

    2013-05-01

    Residual feed intake (RFI) is a measure of an individual's efficiency in utilizing feed for maintenance and production during growth or lactation, and is defined as the difference between the actual and predicted feed intake of that individual. The objective of this study was to relate RFI to feeding behavior and to identify behavioral differences between animals with divergent RFI. The intakes and body weight (BW) of 1,049 growing dairy heifers (aged 5-9 mo; 195 ± 25.8 kg of BW) in 5 cohorts were measured for 42 to 49 d to ascertain individual RFI. Animals were housed in an outdoor feeding facility comprising 28 pens, each with 8 animals and 1 feeder per pen, and were fed a dried, cubed alfalfa diet. This forage diet was chosen because most dairy cows in New Zealand are grazed on ryegrass-dominant pastures, without grain or concentrates. An electronic feed monitoring system measured the intake and feeding behavior of individuals. Feeding behavior was summarized as daily intake, daily feeding duration, meal frequency, feeding rate, meal size, meal duration, and temporal feeding patterns. The RFI was moderately to strongly correlated with intake in all cohorts (r=0.54-0.74), indicating that efficient animals ate less than inefficient animals, but relationships with feeding behavior traits (meal frequency, feeding duration, and feeding rate) were weak (r=0.14-0.26), indicating that feeding behavior cannot reliably predict RFI in growing dairy heifers. Comparison of the extremes of RFI (10% most and 10% least efficient) demonstrated similar BW and average daily gain for both groups, but efficient animals ate less; had fewer, longer meals; shorter daily feeding duration; and ate more slowly than the least-efficient animals. These groups also differed in their feeding patterns over 24h, with the most efficient animals eating less and having fewer meals during daylight (0600 to 2100 h), especially during the afternoon (1200 to 1800 h), but ate for a longer time during

  15. Variation in residual feed intake in Holstein-Friesian dairy heifers in southern Australia.

    Science.gov (United States)

    Williams, Y J; Pryce, J E; Grainger, C; Wales, W J; Linden, N; Porker, M; Hayes, B J

    2011-09-01

    Feed conversion efficiency of dairy cattle is an important component of the profitability of dairying, given that the cost of feed accounts for much of total farm expenses. Residual feed intake (RFI) is a useful measure of feed conversion efficiency, as it can be used to compare individuals with the same or differing levels of production during the period of measurement. If genetic variation exists in RFI among dairy cattle, selection for lower RFI could improve profitability. In this experiment, RFI was defined as the difference between an animal's actual feed intake and its expected feed intake, which was determined by regression of dry matter (DM) intake against mean body weight (BW) and growth rate. Nine hundred and three Holstein-Friesian heifer calves, aged between 5 and 7 mo, were measured for RFI in 3 cohorts of approximately 300 animals. Calves were housed under feedlot style conditions in groups of 15 to 20 for 85 to 95 d and had ad libitum access to a cubed alfalfa hay. Intakes of individual animals were recorded via an electronic feed recording system and BW gain was determined by weighing animals once or twice weekly, over a period of 60 to 70 d. Calves had DM intake (mean ± SD) of 8.3±1.37 kg of DM/d over the measurement period with BW gains of 1.1±0.17 kg/d. In terms of converting feed energy for maintenance and growth, the 10% most efficient calves (lowest RFI) ate 1.7 kg of DM less each day than the 10% least efficient calves (highest RFI) for the same rate of growth. Low-RFI heifers also had a significantly lower rate of intake (g/min) than high-RFI heifers. The heritability estimate of RFI (mean ± SE) was 0.27 (±0.12). These results indicate that substantial genetic variation in RFI exists, and that the magnitude of this variation is large enough to enable this trait to be considered as a candidate trait for future dairy breeding goals. A primary focus of future research should be to ensure that calves that are efficient at converting feed

  16. Embryo production with sex-sorted semen in superovulated dairy heifers and cows.

    Science.gov (United States)

    Kaimio, I; Mikkola, M; Lindeberg, H; Heikkinen, J; Hasler, J F; Taponen, J

    2013-11-01

    The aim of this study was to examine the effect of sex-sorted semen on the number and quality of embryos recovered from superovulated heifers and cows on commercial dairy farm conditions in Finland. The data consist of 1487 commercial embryo collections performed on 633 and 854 animals of Holstein and Finnish Ayrshire breeds, respectively. Superovulation was induced by eight intramuscular injections of follicle-stimulating hormone, at 12-hour intervals over 4 days, involving declining doses beginning on 9 to 12 days after the onset of standing estrus. The donors were inseminated at 9 to 15-hour intervals beginning 12 hours after the onset of estrus with 2 + 2 (+1) doses of sex-sorted frozen-thawed semen (N = 218) into the uterine horns or with 1 + 1 (+1) doses of conventional frozen-thawed semen (N = 1269) into the uterine corpus. Most conventional semen (222 bulls) straws contained 15 million sperm (total number 30-45 million per donor). Sex-sorted semen (61 bulls) straws contained 2 million sperm (total number 8-14 million per donor). Mean number of transferable embryos in recoveries from cows bred with sex-sorted semen was 4.9, which is significantly lower than 9.1 transferable embryos recovered when using conventional semen (P ≤ 0.001). In heifers, no significant difference was detected between mean number of transferable embryos in recoveries using sex-sorted semen and conventional semen (6.1 and 7.2, respectively). The number of unfertilized ova was higher when using sex-sorted semen than when using conventional semen in heifers (P cows (P cows (P protocol used seemed to be adequate for heifers. In superovulated cows, an optimal protocol for using sex-sorted semen remains to be found.

  17. Effect of trace minerals and starch on digestibility and rumen fermentation in diets for dairy heifers.

    Science.gov (United States)

    Pino, F; Heinrichs, A J

    2016-04-01

    The objective of this study was to evaluate the effect of different forms of trace minerals (TM) and the use of different starch levels in dairy heifer diets on rumen fermentation and digestibility. Eight rumen cannulated dairy heifers (15.4 ± 0.8 mo of age and 438.31 ± 18.08 kg of body weight) were subjected to a split-plot, 4 × 4 Latin square design with 19-d periods: 15d of adaptation and 4d of sampling. The whole-plot factor was type of TM; organic as proteinates (OTM) or inorganic sulfates (ITM), and the subplot was starch level (3.54, 12.95, 22.25, and 31.73%). Total collection of feces and urine was completed on d 15 to 19 to determine digestibility and TM excretion. Rumen contents were sampled on d 18 to 19 at 0, 1, 2, 4, 8, 12, 16, 20, and 22 h after feeding to measure pH and volatile fatty acid (VFA) concentrations. Plasma samples were collected to evaluate TM concentrations and enzymatic activity for ceruloplasmin, glutathione peroxidase, and superoxide dismutase. Starch level affected pH, individual VFA concentrations, and nutrient excretion. Trace mineral intake was lower for OTM compared with ITM. No effect of TM form on dry matter digestibility was detected, but as level of starch increased, diet dry matter digestibility increased. Rumen pH was lower for diets with OTM, which is consistent with higher total VFA production and butyrate proportion observed for heifers fed OTM diets. These variables may be explained by the higher bioavailability of OTM and faster utilization and fermentation by rumen microorganisms. Heifers that consumed ITM had higher moisture in feces and higher urine excretion, which increased total manure production. Total excretion of TM was not different by treatment. Blood plasma mineral concentration was not different between treatments except for Mn, which was higher for OTM. Enzymatic activity was not affected by treatments. Mineral intake was reduced and blood mineral levels were not different, suggesting enhanced

  18. The influence of oestrous substances on cyclicity and oestrous behaviour in dairy heifers

    Directory of Open Access Journals (Sweden)

    Nordéus Kristina

    2012-04-01

    Full Text Available Abstract Background Declining fertility is a major concern for dairy farmers today. One explanation is shorter and weaker expression of oestrus in dairy cows making it difficult to determine optimal time for artificial insemination (AI. Chemical communication is of interest in the search for tools to detect oestrus or to synchronise or enhance oestrous periods. Pheromones, used in chemical communication within species, can influence reproduction in different ways. The aim here was to investigate whether oestrous cycle length, and duration and intensity of oestrous expression in dairy heifers could be manipulated through exposure to pheromones in oestrual substances from other females. Methods Beginning on day 16 of two consecutive control oestrous cycles, ten heifers of the Swedish Red Breed (SRB were exposed to water. During the two following cycles the heifers were exposed to urine and vaginal mucus, obtained from cows in oestrus. Cyclicity parameters were monitored through hormone measurements, oestrus detection and ultrasonographic examination. Results We found no difference in cycle length or in duration of standing oestrus between control and treatment. We did, however, find a tendency of interaction between type of exposure (control or treatment and cycle number within type of exposure for cycle length (p = 0.068, with the length differing less between the treatment cycles. We also found a tendency of effect of type of exposure on maximal concentration (p = 0.073 and sum of concentrations (p = 0.063 of LH during the LH surge, with values being higher for the control cycles. There were also significant differences in when the different signs of oestrus occurred and in the intensity of oestrous expression. The score for oedema and hyperaemia of external genitalia was significantly higher (p = 0.004 for the control cycles and there was also a significant interaction between type of exposure and time period for restlessness (p = 0.011, with

  19. Intake and digestion of whole-crop barley and wheat silages by dairy heifers.

    Science.gov (United States)

    Rustas, B-O; Bertilsson, J; Martinsson, K; Elverstedt, T; Nadeau, E

    2011-12-01

    The effect of maturity at harvest on the digestibility and intake of large bale silage made from whole-crop barley and wheat when fed to growing heifers was evaluated. Two crops of spring barley (Hordeum distichum cv. Filippa and Kinnan) and 1 of winter wheat (Triticum aestivum cv. Olevin) were harvested at the heading, milk, and dough stages of maturity. The silage was fed to 36 dairy heifers in a balanced crossover experiment with 3 periods and 9 treatments (diets based on 3 crops and 3 stages of maturity), organized into 6 pairs of 3 × 3 Latin squares. No clear relationship was observed between intake and stage of maturity of whole-crop cereal silage, but intake was positively correlated to silage DM content (P silage (P = 0.034). The NDF digestibility decreased between the heading and milk stages in all crops (P < 0.001), whereas it decreased in 1 barley crop (P < 0.001), increased in the other barley (P = 0.025), and was unchanged in the wheat between the milk and dough stages of maturity. Starch digestibility was less in the 2 barley crops compared with the wheat at the dough stage of maturity (P < 0.001). The feeding value of the whole-crop barley and wheat declined between the heading and milk stages of maturity, but thereafter the effect of maturity on the feeding value was minor.

  20. Baker's yeast effluent as a liquid feed for dairy cows and heifers.

    Science.gov (United States)

    Blauwiekel, R; Loney, K A; Riley, R E

    1995-02-01

    Liquid effluent from baker's yeast production was fed to dairy cows to determine whether effluent is an acceptable feed and whether it affects milk yield or composition. Effluent averaged 5.4% DM and 6.1% N (DM basis). In experiment 1, 20 Holstein cows were offered effluent free choice or no effluent for 8 wk. Milk yield, composition, and group feed intake were measured. In Experiment 2, 20 cows were fed effluent blended into the TMR (11.3 L/d per cow) or no effluent for 4 wk. In Experiment 3, six groups of 6 heifers were offered free choice or no effluent. Free choice intake of effluent peaked at 15 L/d per cow at wk 3 but declined to 5.3 L/d per cow by wk 6. Milk and 3.5% FCM yields were not affected by effluent regardless of feeding system. Milk protein and fat percentages were higher for cows offered effluent free choice. Milk protein percentage and yield were lower with effluent in the TMR. Intake of effluent by heifers was 1.05 L/d, and effluent did not affect DMI or weight gain. Acceptability of yeast effluent fed free choice is poor, but when yeast is blended into the TMR, cows consume effluent without adverse effects on milk yield or DMI.

  1. Radionuclides in milk of dairy heifers raised on forages harvested from phosphatic clay soils on reclaimed mined land

    Energy Technology Data Exchange (ETDEWEB)

    Staples, C.R.; Umana, R.; Hayen, M.J. [Univ. of Florida, Gainesville, FL (United States)] [and others

    1994-07-01

    Alfalfa (AR; Medicago sativa L.) and corn (CSR; Zea mays L.) were grown in phosphatic clay soils on phosphate-mined reclaimed land in central Florida. Corn (CSC) also was grown on unmined land and served as a control forage. Upon harvesting, plants were chopped and ensiled. Concentrations of {sup 226}Ra averaged 2.44, 0.26 and 0.15; {sup 210}Pb averaged 1.04, 0.63, and 0.52; and {sup 210}Po averaged 1.59, 0.59, and 1.26 Bq kg{sup -1} DM for AR, CSR, and CSC, respectively. These forages were fed separately to Holstein dairy replacement heifers (Bos taurus) (n=15 per forage) from approximately 9 to 25 mo of age. Heifers gave birth to calves at approximately 24 mo of age. Samples of milk were collected on d 1, 15, and 30 of lactation and analyzed for radionuclides. Averaged across sampling days, heifers fed AR had greater milk concentrations of {sup 226}Ra compared with those fed CSR (0.27 vs. 0.22 Bq kg{sup -1} DM; P < 0.10), which, in turn, had greater milk concentrations compared with heifers fed CSC (0.22 vs. 0.13 Bq kg{sup -1} DM; P < 0.05). Heifers fed AR also had greater milk concentrations of {sup 210}Po compared with heifers fed CSR (0.58 vs. 0.30 Bq kg{sup -1} DM; P < 0.10), but values of CSR-fed heifers were not different from CSC-fed heifers (0.45 Bq kg{sup -1} DM). Lead-210 was greater in milk from heifers fed CSR compared with those fed AR or CSC (1.38 vs. 0.94 and 0.92 Bq kg{sup -1} DM; P < 0.13), respectively. Plasma S and Cu concentrations suggested subclinical molybdenosis in heifers fed AR. However, all heifers grew at an acceptable rate, conceived normally, had normal gestation periods, gave high quality colostrum at calving, and produced similar amounts of milk. 17 refs., 9 tabs.

  2. Dairy heifer manure management, dietary phosphorus, and soil test P effects on runoff phosphorus.

    Science.gov (United States)

    Jokela, William E; Coblentz, Wayne K; Hoffman, Patrick C

    2012-01-01

    Manure application to cropland can contribute to runoff losses of P and eutrophication of surface waters. We conducted a series of three rainfall simulation experiments to assess the effects of dairy heifer dietary P, manure application method, application rate, and soil test P on runoff P losses from two successive simulated rainfall events. Bedded manure (18-21% solids) from dairy heifers fed diets with or without supplemental P was applied on a silt loam soil packed into 1- by 0.2-m sheet metal pans. Manure was either surface-applied or incorporated (Experiment 1) or surface-applied at two rates (Experiment 2) to supply 26 to 63 kg P ha. Experiment 3 evaluated runoff P from four similar nonmanured soils with average Bray P1-extractable P levels of 11, 29, 51, and 75 mg kg. We measured runoff quantity, total P (TP), dissolved reactive P (DRP), and total and volatile solids in runoff collected for 30 min after runoff initiation from two simulated rain events (70 mm h) 3 or 4 d apart. Manure incorporation reduced TP and DRP concentrations and load by 85 to 90% compared with surface application. Doubling the manure rate increased runoff DRP and TP concentrations an average of 36%. In the same experiment, P diet supplementation increased water-extractable P in manure by 100% and increased runoff DRP concentration threefold. Concentrations of solids, TP, and DRP in runoff from Rain 2 were 25 to 75% lower than from Rain 1 in Experiments 1 and 2. Runoff DRP from nonmanured soils increased quadratically with increasing soil test P. These results show that large reductions in P runoff losses can be achieved by incorporation of manure, avoiding unnecessary diet P supplementation, limiting manure application rate, and managing soils to prevent excessive soil test P levels.

  3. Effect of feeding rumen-protected rice bran on mineral status of non-lactating dairy heifers.

    Science.gov (United States)

    Martín-Tereso, J; Distefano, C; van Laar, H; Mulder, K; den Hartog, L A; Verstegen, M W A

    2011-02-01

    Adapting Ca homeostasis of dairy cows before calving can prevent milk fever. Rice bran, treated with formaldehyde to prevent ruminal degradation of phytic acid, was fed to heifers to study its effect on Ca homeostasis. For 3 weeks 18 heifers were supplemented 3 kg of two feeds: placebo (PF) and rice bran (RBF), defining three treatments: control (CRT), low dose (LD) and high dose (HD). In weeks 1 and 3, all animals received 3 kg of PF and in week 2: CRT received 3 kg of PF, LD received 1.5 kg of PF and 1.5 kg of RBF and HD received 3 kg of RBF. Treatments did not affect dry matter intake (DMI). Feed intakes and growth rates indicated that all heifers had nutritional requirements that exceeded their Ca intakes. Serum Ca, urinary Ca, calcitriol or hydroxyproline remained unaffected. Urinary Ca was consistently low indicating high renal Ca reabsorption, which is indicative of insufficient Ca supply. Rice bran feed influenced P, Mg and Zn intakes and serum and urine presence of these minerals. Most heifers already presented an upregulated Ca metabolism, being inadequate to study adaptive changes in Ca homeostasis of multiparous dry cows. This metabolic difference can be explanatory to the very low susceptibility of heifers to milk fever, further supporting the induction of homeostatic adaptation before calving to prevent milk fever. Rice bran feed did not reduce DMI, and was not detrimental to P, Mg or Zn status.

  4. Effect of early lactation foot trimming in lame and non-lame dairy heifers: a randomised controlled trial.

    Science.gov (United States)

    Maxwell, O J R; Hudson, C D; Huxley, J N

    2015-07-25

    Foot trimming is a common management intervention in prevention of lameness in dairy cattle. Despite this, there is surprisingly limited experimental evidence on its efficacy, especially in regard to primiparous heifers. A randomised, negatively controlled trial was conducted to investigate the association between an early lactation foot trim on primiparous animals and production outcomes. 282 heifers were enrolled from eight farms in the UK, and randomly assigned to treatment or control groups. Milk yield (305-day-adjusted whole-milk yield) was not significantly different between groups (trimmed 7727 litres, untrimmed 7646 litres). However, multivariate regression analysis demonstrated that this relationship was confounded by lameness state. Animals that were lame at the time of trimming gave significantly more milk (734 litres, P=0.02) than those that were non-lame and untrimmed. The present results suggest that, based on milk production alone, it would not have been cost beneficial to trim all heifers; however, a targeted intervention aimed at lame animals would have delivered a substantial return on investment. As a very minimum, the authors recommend heifers should be regularly assessed in early lactation, and treated as soon as they are identifiably lame. The high prevalence of lesions identified suggests routine trimming for all heifers may be justifiable on welfare grounds even if the milk-yield benefits are marginal.

  5. Influence of primiparity on size at birth, growth, the somatotrophic axis and fertility in dairy heifers.

    Science.gov (United States)

    Swali, A; Wathes, D C

    2007-11-01

    Epidemiological studies in humans suggest that small size at birth is a predictor of some adult diseases. Nutritional constraint experienced in utero may result in fetal adaptations, which alter subsequent body structure and physiology. Size at birth is influenced by maternal age and parity. Most dairy cows are bred for the first time at about 60% of their mature body weight and therefore carry their first pregnancy whilst still growing. We hypothesized that this might alter the nutritional environment in utero and thus influence the development of the calf. This study compared birth size, growth rates and fertility in consecutively born heifer offspring of 45 primiparous (PP) and 71 multiparous (MP) dairy cows on one farm. Measures of the somatotrophic axis (GH, insulin, IGF-I and glucose) were compared in blood samples collected at the start of the first lactation. Offspring of PP cows were significantly smaller at birth (weight, length, height, girth, Pprimiparous dam resulted in a smaller size at birth and influenced the somatotrophic axis around calving. Fertility was generally better in offspring of PP than MP dams.

  6. Potential gains in lifetime net merit from genomic testing of cows, heifers, and calves on commercial dairy farms.

    Science.gov (United States)

    Weigel, K A; Hoffman, P C; Herring, W; Lawlor, T J

    2012-04-01

    The objective of this study was to quantify the gains in genetic potential of replacement females that could be achieved by using genomic testing to facilitate selection and culling decisions on commercial dairy farms. Data were simulated for 100 commercial dairy herds, each with 1,850 cows, heifers, and calves. Parameters of the simulation were based on the US Holstein population, and assumed reliabilities of traditional and genomic predictions matched reliabilities of animals that have been genotyped to date. Selection of the top 10, 20, 30, …, 90% of animals within each age group was based on parent averages and predicted transmitting abilities with or without genomic testing of all animals or subsets of animals that had been presorted by traditional predictions. Average gains in lifetime net merit breeding value of selected females due to genomic testing, minus prorated costs of genotyping the animals and their unselected contemporaries, ranged from $28 (top 90% selected) to $259 (top 20% selected) for heifer calves with no pedigrees, $14 (top 90% selected) to $121 (top 10% selected) for heifer calves with known sires, and $7 (top 90% selected) to $87 (top 20% selected) for heifer calves with full pedigrees. In most cases, gains in genetic merit of selected heifer calves far exceeded prorated genotyping costs, and gains were greater for animals with missing or incomplete pedigree information. Gains in genetic merit due to genomic testing were smaller for lactating cows that had phenotypic records, and in many cases, these gains barely exceeded or failed to exceed genotyping costs. Strategies based on selective genotyping of the top, middle, or bottom 50% of animals after presorting by traditional parent averages or predicted transmitting abilities were cost effective, particularly when pedigrees or phenotypes were available and a relatively small proportion of animals were to be selected or culled. Based on these results, it appears that routine genotyping of

  7. Lameness in dairy heifers; impacts of hoof lesions present around first calving on future lameness, milk yield and culling risk.

    Science.gov (United States)

    Randall, L V; Green, M J; Chagunda, M G G; Mason, C; Green, L E; Huxley, J N

    2016-10-01

    The importance of lameness in primiparous dairy heifers is increasingly recognised. Although it is accepted that clinical lameness in any lactation increases the risk of future lameness, the impact of foot lesions during the first lactation on long-term lameness risk is less clear. This retrospective cohort study aimed to investigate the impacts of foot lesions occurring around the time of first calving in heifers on future lameness risk, daily milk yield and survival within a dairy herd. Records were obtained for 158 heifers from one UK dairy herd. Heifers were examined in 2 month blocks from 2 months pre-calving through to 4 months post-calving. Sole lesions and white line lesions were scored on a zero to 10 scale and digital dermatitis on a zero to 3 scale. Outcomes investigated were; lameness risk based on weekly locomotion scores, average daily milk yield and culling risk. Mixed effect models were used to investigate associations between maximum lesion scores and outcomes. Lesion scores in the highest score categories for claw horn lesions (sole lesions and white line lesions) in the 2 to 4 month post-calving period were associated with an increased risk of future lameness; heifers with white line lesion scores ≥3 compared with scores zero to 1 and heifers with sole lesion scores ≥4 compared with score 2, at this time point, had a predicted increased risk of future lameness of 1.6 and 2.6 respectively. Sole lesions ≥4 were also associated with a reduction in average daily milk yield of 2.68kg. Managing heifers to reduce claw horn lesions during this time period post-calving may provide health, welfare and production benefits for the long-term future of those animals. A novel finding from the study was that mild lesion scores compared with scores zero to 1, were associated with a reduced risk of future lameness for white line lesions and sole lesions occurring in the pre-calving or 2 to 4 months post-calving periods respectively. Mild sole lesions in the

  8. Genetic aspects of feed intake and efficiency in lactating dairy heifers.

    NARCIS (Netherlands)

    Arendonk, van J.A.M.; Nieuwhof, G.J.; Vos, H.; Korver, S.

    1991-01-01

    In 1982, an experiment was initiated to study the relationships between feed intake and feed efficiency of young AI bulls, growing heifers and lactating heifers. This paper focuses on the genetic parameters for feed intake, production, and efficiency of lactating heifers. Measurements of feed

  9. Effect of feeding urea-molasses blocks with incorporated fenbendazole on grazing dairy heifers naturally infected with gastrointestinal nematodes.

    Science.gov (United States)

    Waruiru, R M; Onyando, C O; Machuka, R O

    2003-06-01

    Between June 1999 and August 2000, the effects of feeding medicated urea-molasses supplement blocks on the growth of dairy heifers in a marginal area of central Kenya were assessed by comparing the live-weight gain of supplemented and unsupplemented heifers grazing the same pasture. Thirty-nine heifers with an average age of 9.6 months were initially treated orally with albendazole (10 mg/kg body weight) and assigned to 3 groups: group I was fed urea-molasses blocks with incorporated fenbendazole (MUMB), group II was fed urea-molasses blocks (UMB) and group III heifers (control) received no block supplementation (NBS). Body weights of the heifers and faecal egg counts (FECs) were measured monthly and larval cultures were made of positive faecal samples of each group. The mean cumulative live-weight responses of the MUMB and UMB groups were significantly greater than the NBS group (P 0.05). The FECs were moderate to low in all groups and decreased progressively with increasing age of the animals; FECs for the urea-molasses-supplemented groups remained significantly lower than those of the NBS group throughout the experimental period (P < 0.05). Haemonchus and Trichostrongylus were the predominant nematode genera found in the heifers, but Cooperia, Bunostomum and Oesophagostomum were also present. These results indicate that feeding of urea-molasses blocks substantially reduced production losses attributable to nematode infection of young grazing cattle, and confirms previous observations that well-fed animals are better able to overcome the effects of helminth infections.

  10. Effect of feeding urea-molasses blocks with incorporated fenbendazole on grazing dairy heifers naturally infected with gastrointestinal nematodes

    Directory of Open Access Journals (Sweden)

    R.M. Waruiru

    2003-06-01

    Full Text Available Between June 1999 and August 2000, the effects of feeding medicated urea-molasses supplement blocks on the growth of dairy heifers in a marginal area of central Kenya were assessed by comparing the live-weight gain of supplemented and unsupplemented heifers grazing the same pasture. Thirty-nine heifers with an average age of 9.6 months were initially treated orally with albendazole (10 mg / kg body weight and assigned to 3 groups : group I was fed urea-molasses blocks with incorporated fenbendazole (MUMB, group II was fed urea-molasses blocks (UMB and group III heifers (control received no block supplementation (NBS. Body weights of the heifers and faecal egg counts (FECs were measured monthly and larval cultures were made of positive faecal samples of each group. The mean cumulative live-weight responses of the MUMB and UMB groups were significantly greater than the NBS group (P < 0.05. However, at the end of the experimental period, the mean weight gain of the MUMB group did not differ from that of the UMB group (P >0.05. The FECs were moderate to low in all groups and decreased progressively with increasing age of the animals; FECs for the urea-molasses-supplemented groups remained significantly lower than those of the NBS group throughout the experimental period (P <0.05. Haemonchus and Trichostrongylus were the predominant nematode genera found in the heifers, but Cooperia, Bunostomum and Oesophagostomum were also present. These results indicate that feeding of urea-molasses blocks substantially reduced production losses attributable to nematode infection of young grazing cattle, and confirms previous observations that well-fed animals are better able to overcome the effects of helminth infections.

  11. Effects of grain, fructose, and histidine feeding on endotoxin and oxidative stress measures in dairy heifers.

    Science.gov (United States)

    Golder, H M; Lean, I J; Rabiee, A R; King, R; Celi, P

    2013-01-01

    Ruminal endotoxin and plasma oxidative stress biomarker concentrations were studied in dairy heifers challenged with grain, fructose, and histidine in a partial factorial study. Holstein-Friesian heifers [n=30; average body weight (BW) of 359.3±47.3 kg] were randomly allocated to 5 treatment groups: (1) control (no grain); (2) grain [crushed triticale at 1.2% of BW dry matter intake (DMI)]; (3) grain (0.8% of BW DMI) + fructose (0.4% of BW DMI); (4) grain (1.2% of BW DMI) + histidine (6g/head); and (5) grain (0.8% of BW DMI) + fructose (0.4% of BW DMI) + histidine (6 g/head). Rumen samples were collected by stomach tube 5, 65, 115, 165, and 215 min after diet consumption and blood samples at 5 and 215 min after consumption. Rumen fluid was analyzed for endotoxin concentrations. Plasma was analyzed for concentrations of the following oxidative stress biomarkers: reactive oxygen metabolites (dROM), biological antioxidant potential (BAP), advanced oxidation protein products, and ceruloplasmin, and activity of glutathione peroxidase. Dietary treatment had no effect on concentrations of endotoxin or oxidative stress biomarkers. We observed no interactions of treatment by time. Ruminal concentrations of endotoxin decreased during the sampling period from 1.12×10(5) ± 0.06 to 0.92×10(5) endotoxin units/mL ± 0.05 (5 and 215 min after diet consumption, respectively). Concentrations of dROM and the oxidative stress index (dROM/BAP × 100) increased over the sampling period, from 108.7 to 123.5 Carratelli units (Carr U), and from 4.1 to 4.8, respectively. Ceruloplasmin concentrations markedly declined 5 min after the consumption of diets, from 190 to 90 mg/L over the 215-min sampling period. Overall, a single feeding challenge for dairy cattle with grain, fructose, and histidine, and combinations thereof, may not be sufficient to induce marked changes in endotoxin or oxidative stress biomarker concentrations.

  12. An Unusual Occurrence of Actinobacillosis in Heifers and Cows in A Dairy Herd in Tehran suburb-Iran

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    Atyabi, N.,

    2010-07-01

    Full Text Available An unusual occurrence of actinobacillosis was diagnosed in 4 heifers aged 8-15 months and 2 cattle in a dairy herd with 190 Iranian Holstein breed. Anorexia, dysphagia, drooling of normal or foodtinged saliva and presence of warts-like lesions on the dorsal surface of tongue shaft were observed in a 15-month-old heifer without showing protrusion of tongue or presenting woody tongue and no involvement of either sulcus lingualis or tongue base. In addition to tongue, soft tissues of oral cavity and pharyngeal region including lymph nodes, salivary glands and tonsils were contained multiple whitish nodules. Histopathologically, typical pyogranulomas of actinobacillosis contained radiating eosinophilic clubs surrounded by many neutrophils were diagnosed. Actinobacillus lignieresii was isolated from the lesions in pure culture. Clinical examination of other animals revealed the presence of different degrees of granulomatous abscesses in soft tissues including skin around mandibles in at least 3 heifers aged 8-11 months and 2 cattle. Due to 4 recent droughty years feeding the heifers, dry cows and low milk producing cattle by cheap oat and wheat straw mixed with plant awns could be the cause of this event.

  13. Effects of co-grazing dairy heifers with goats on animal performance, dry matter yield, and pasture forage composition.

    Science.gov (United States)

    Dennis, T S; Unruh-Snyder, L J; Neary, M K; Nennich, T D

    2012-12-01

    Mixed livestock grazing can offer an alternative management system for rearing dairy replacement heifers (Bos taurus). A 2-yr study was conducted during 2009 (yr 1) and 2010 (yr 2) to determine the effects of co-grazing Holstein heifers under rotational stocking with Boer × Kiko goats on animal performance, pasture DM yield, and botanical composition. Each year, 24 heifers (134 ± 6 d of age and 147.4 ± 31.2 kg BW in yr 1; 166 ± 11 d of age and 168.0 ± 27.6 kg BW in yr 2) and 6 goats (2 yr old and 39.7 ± 16.2 kg BW in yr 1; 1 yr old and 33.7 ± 7.4 kg BW in yr 2) were divided into 6 paddocks with 4 heifers and 2 goats, where applicable, per group. Low endophyte-infected tall fescue (Festuca arundinacea Schreb.) and white clover (Trifolium repens L.) pastures were used to evaluate 2 grazing strategies (heifers grazed alone [HO] or heifers co-grazed with goats [HG]). In addition, 6 goats were assigned to 2 paddocks and grazed alone (GO) each year to estimate goat pasture forage intake and compare Haemonchus contortus infection to co-grazed goats. Forage samples were taken monthly to assess DM yield and botanical composition. Samples collected for botanical composition were manually sorted into grass, legume, and weed species. Forage DMI was estimated using a rising plate meter before and after grazing. Heifer BW at the conclusion of yr 1 and yr 2 did not differ between HO and HG (P = 0.40 and P = 0.12, respectively). Likewise, overall ADG did not differ between HO and HG, averaging 0.65 kg/d and 0.63 kg/d over both grazing seasons (P = 0.70). Grazing strategy did not affect forage or total DMI in yr 1; however, HO consumed 2.3 kg/d more forage DM than HG (P < 0.01), resulting in greater total DMI for HO in yr 2 (P < 0.01). Heights at the hip and withers were greater for HO than for HG during both grazing seasons (P < 0.05). Weed presence did not differ between grazing strategies over both grazing seasons as determined by manual harvesting, but visual estimation

  14. Effects of flooring and restricted freestall access on behavior and claw health of dairy heifers.

    Science.gov (United States)

    Ouweltjes, W; van der Werf, J T N; Frankena, K; van Leeuwen, J L

    2011-02-01

    Claw health, locomotion, feed intake, milk yield, body weight, activity, and lying and standing behavior of dairy heifers were monitored in a single dairy herd during the first 3 mo after calving. During the first 8 wk after calving, 2 treatments were applied: restricted freestall access by closing the stalls between 2300 h and 0500 h (yes or no) and alley flooring (concrete or rubber topped slatted floors). Apart from treatments, housing was identical. The animals were kept in small groups (n=4 to 6) in adjacent barn pens. Thereafter, the animals were kept in 1 group in a freestall section with concrete slatted floor and unrestricted access to the stalls for 5 wk. All animals were fed the same partial mixed ration. We hypothesized that (1) hard flooring causes high mechanical load of the claws and (2) restricted freestall access causes prolonged standing bouts and reinforced effects of hard flooring on claws. The heifers had only minor claw lesions before first calving, and the prevalence and severity of sole hemorrhages increased during the first 3 mo after calving (from 0.24 ± 0.08 to 1.18 ± 0.14 and from 0.04 ± 0.01 to 0.24 ± 0.02, respectively), particularly in the outer hind claws. Animals kept on rubber alley flooring had lower average hemorrhage scores in wk 9 (0.13 ± 0.03 vs. 0.21 ± 0.03) and wk 14 (0.20 ± 0.03 vs. 0.27 ± 0.03) after calving, had a slower feed intake (3.05 ± 0.14 vs. 3.46 ± 0.14 g/s) and spent more time feeding (7.3 ± 0.3 vs. 6.6 ± 0.3 min/h) than animals kept on hard concrete alley floors. Restricted freestall access resulted in fewer standing bouts per day (14.4 ± 1.0 vs. 17.9 ± 1.0) and more strides per hour (99.8 ± 5.4 vs. 87.2 ± 5.4) without changing overall standing time (15.0 ± 0.3 vs. 14.7 ± 0.3 h/d) and did not affect the occurrence of sole hemorrhages. The animals with no overnight freestall access spent more time standing (55.9 ± 0.9 vs. 35.8 ± 0.9 min/h) and feeding (7.8 ± 0.3 vs. 4.3 ± 0.3 min/h) between

  15. Hormonal manipulations in the 5-day timed artificial insemination protocol to optimize estrous cycle synchrony and fertility in dairy heifers.

    Science.gov (United States)

    Lima, F S; Ribeiro, E S; Bisinotto, R S; Greco, L F; Martinez, N; Amstalden, M; Thatcher, W W; Santos, J E P

    2013-01-01

    Objectives were to determine the effects of GnRH at the initiation of the 5-d timed artificial insemination (AI) program combined with 2 injections of PGF2α on ovarian responses and pregnancy per AI (P/AI) in dairy heifers, and the role of progesterone concentrations on LH release and ovulation in response to GnRH. In study 1, heifers received a controlled internal drug release (CIDR) insert containing 1.38 g of progesterone on d 0, an injection of 25 mg of PGF2α and CIDR removal on d 5, and an injection of 100 μg GnRH concurrently with AI on d 8. Heifers were assigned to receive no additional treatment (control; n=559) or an injection of GnRH on d 0 and a second injection of PGF2α on d 6 (G2P; n=547). In study 2, all heifers were treated as described for the control in study 1, and were allocated to receive no additional treatment (control; n=723), an injection of PGF2α on d 6 (NG2P; n=703), or an injection of GnRH on d 0 and an injection of PGF2α on d 6 (G2P; n=718). In study 3, heifers received a CIDR on d 7 after ovulation and were assigned randomly to a low-progesterone (LP; n=6) treatment in which 2 injections of 25 mg of PGF2α each were administered 12h apart, on d 7 and 7.5 after ovulation, or to a high-progesterone (HP; n=12) treatment in which no PGF2α was administered. On d 8, heifers received 100 μg of GnRH and blood was sampled at every 15 min from -30 to 180 min relative to the GnRH for assessment of LH concentrations. Additionally, 94 heifers were assigned to LP or HP and ovulation in response to GnRH was evaluated. In study 1, P/AI was greater for G2P than for the control on d 32 (59.4 vs. 53.5%) and 60 after AI (56.6 vs. 51.3%). In study 2, administration of GnRH on d 0 increased the proportion of heifers with a new corpus luteum on d 5 (control=21.9 vs. NG2P=20.1 vs. G2P=34.4%). Administration of a second PGF2α increased the proportion of heifers with progesterone <0.5 ng/mL at AI (control=83.1 vs. NG2P=93.0 and G2P=87.2%). Pregnancy per

  16. Measuring residual feed intake in dairy heifers fed an alfalfa (Medicago sativa) cube diet.

    Science.gov (United States)

    Waghorn, G C; Macdonald, K A; Williams, Y; Davis, S R; Spelman, R J

    2012-03-01

    Selection for divergence between individuals for efficiency of feed utilization (residual feed intake, RFI) has widespread application in the beef industry and is usually undertaken when animals are fed diets based on silages with grain. The objective of this research was to develop a feeding system (using Gallagher, Hamilton, New Zealand, electronics) to measure RFI for growth in Holstein-Friesian heifers (aged 5-9 mo), and identify divergent individuals to be tested for RFI during lactation. A dry forage diet (alfalfa cubes) was fed because intakes could be measured accurately, and the New Zealand dairy industry (4.4 million milking cows in lactation) relies heavily on forage feeding. The evaluation was undertaken over 3 yr with 1,052 animals fed in a facility for 7 wk, and weighed 3 times weekly. The mean age at the start of measurements was 215 d, body weight (BW) 189 kg, and mean daily dry matter intakes averaged 6.7 kg. Body weight gain (all animals) averaged 0.88 kg/d. The RFI was determined as the residuals from the regression of mean intake on mean BW(0.75) and daily BW gain of individuals. Actual and fitted intakes were strongly related (R(2) = 0.82). In terms of gross efficiency (feed intake/BW gain), RFI+year explained 43% of the variation, BW gain+year explained 66%, and RFI+BW gain+year explained 79% of the variation (all Pdry matter/d. The most and least efficient animals will be tested for RFI during lactation and genetic markers will be identified for the trait.

  17. Responses of dairy heifers to the visual cliff formed by a herringbone milking pit: evidence of fear of heights in cows (Bos taurus).

    Science.gov (United States)

    Arnold, Naomi Adele; Ng, Kim Tee; Jongman, Ellen Caroline; Hemsworth, Paul Hamilton

    2007-11-01

    The ability of cows (Bos taurus) to perceive depth has never been experimentally investigated. If cows can perceive depth, the milking pit in commercial milking facilities may be fear provoking for dairy cows, as past research has shown that most land-dwelling species possess an instinctive fear of heights. In the current study, 12 dairy heifers (1-year-old cows) were exposed to a milking pit (depth-exposed group) and 13 heifers (control group) were exposed to a standard change in the environment while they moved through a milking facility over a 5-day treatment period. Heifers in the depth-exposed group showed a higher heart rate (p fear of heights in cows. Copyright 2007 APA.

  18. Comparison of humoral immune responses in dairy heifers vaccinated with 3 different commercial vaccines against bovine viral diarrhea virus and bovine herpesvirus-1.

    Science.gov (United States)

    DesCôteaux, Luc; Cécyre, Dominique; Elsener, Johanne; Beauchamp, Guy

    2003-10-01

    A randomized clinical trial was conducted to compare the humoral immune response to 3 different commercial vaccines in dairy heifers housed in 3 different dairy farms in Quebec. All heifers were seronegative to type 1 bovine viral diarrhea virus (BVDV) (Singer strain), type 2 BVDV (NVSL 125c strain), and bovine herpesvirus-1 (BHV-1) at the beginning of the trial. In addition, control heifers in group 1 remained seronegative to the 2 viruses till the end of the trial. Significant differences in humoral immune responses occurred among the 3 commercial vaccines at 4 weeks and 6 months following vaccination. The vaccine in group 2 elicited higher mean antibody titers and seroconversion rates to both type 1 and type 2 BVDV than that in groups 3 or 4. Vaccines in groups 2 and 3 induced higher mean antibody titers to BHV-1 than did the vaccine in group 4.

  19. Effects of feeding alfalfa stemlage or wheat straw for dietary energy dilution on nutrient intake and digestibility, growth performance and feeding behavior of holstein dairy heifers

    Science.gov (United States)

    Feeding high-quality forage diets may lead to excessive weight gains and over-conditioning for dairy heifers. Restriction of energy density and dry matter intake by using low-energy forages, such as straw, is a good approach for controlling this problem. Alfalfa ...

  20. Randomised controlled trial to evaluate the effect of foot trimming before and after first calving on subsequent lameness episodes and productivity in dairy heifers.

    Science.gov (United States)

    Mahendran, S A; Huxley, J N; Chang, Y-M; Burnell, M; Barrett, D C; Whay, H R; Blackmore, T; Mason, C S; Bell, N J

    2017-02-01

    The objective of this study was to assess both independent and combined effects of routine foot trimming of heifers at 3 weeks pre-calving and 100 days post calving on the first lactation lameness and lactation productivity. A total of 419 pre-calving dairy heifers were recruited from one heifer rearing operation over a 10-month period. Heifers were randomly allocated into one of four foot trimming regimens; pre-calving foot trim and post-calving lameness score (Group TL), pre-calving lameness score and post-calving foot trim (Group LT), pre-calving foot trim and post-calving foot trim (Group TT), and pre-calving lameness score and post-calving lameness score (Group LL, control group). All heifers were scored for lameness at 24 biweekly time points for 1 year following calving, and first lactation milk production data were collected. Following calving, 172/419 (41.1%) of heifers became lame during the study (period prevalence), with lameness prevalence at each time-point following calving ranging from 48/392 (12.2%) at 29-42 days post-calving to 4/379 (1.1%) between 295 and 383 days after calving. The effects of the four treatment groups were not significantly different from each other for overall lameness period prevalence, biweekly lameness point prevalence, time to first lameness event, type of foot lesion identified at dry off claw trimming, or the 4% fat corrected 305-day milk yield. However, increased odds lameness was significantly associated with a pre-calving trim alone (P = 0.044) compared to the reference group LL. The odds of heifer lameness were highest between 0 and 6 weeks post-partum, and heifer farm destination was significantly associated with lameness (OR 2.24), suggesting that even at high standard facilities, environment and management systems have more effect on heifer foot health than trimming.

  1. Um programa para o planejamento da recria de fêmeas oriundas de rebanhos leiteiros A computer program for planning dairy heifer raising

    Directory of Open Access Journals (Sweden)

    Moisés de Andrade Resende Filho

    2002-01-01

    Full Text Available Alimentação e manejo inadequados das novilhas em recria constituem alguns dos entraves ao incremento da produtividade do rebanho leiteiro no Brasil. Nessa fase, o pecuarista deve decidir entre recriar os animais de reposição, adquiri-los ou terceirizar sua criação. Além disso, em se decidindo por recriar suas próprias novilhas, seria importante encontrar a melhor alternativa em termos econômicos. Visando auxiliar o pecuarista a resolver tal questão, apresenta-se um modelo matemático que permite estimar os custos decorrentes da recria de fêmeas de rebanhos leiteiros até atingir o peso recomendado à cobertura. Tal modelo foi inserido em um programa de computador de maneira a permitir a construção de diferentes cenários, considerando-se peso, raça e ganho de peso diário do lote de novilhas. Assim, após contrastar os cenários gerados com as opções de compra das novilhas ou terceirização da recria, o pecuarista aumenta as chances de tomar uma decisão mais lucrativa. Exemplos de utilização do modelo inserido em um programa de computador são apresentados e avaliados.Inadequate feeding and management when raising heifers are two factors that constrain dairy cattle productivity in Brazil. In order to build their heads, Brazilian dairy farmers must choose between three options: to raise their own heifers to breeding age, to purchase mature heifers from outside sources, or to employ a custom heifer raiser. If the dairy farmer chooses to raise his own heifers, he needs to determine the most economically rational production strategy. To aid the farmer in this determination, a mathematical model was developed to create a budget for raising a group of heifers to their recommended breeding weight. This model was embedded in a computer program making it possible to build different growth scenarios, which can be adjusted by breed, desired daily weight gain, and average weight for a given group of heifers. After contrasting the results

  2. Long-term effects of human growth hormone-releasing hormone and photoperiod on hormone release and puberty in dairy heifers.

    Science.gov (United States)

    Ringuet, H; Pelletier, G; Brazeau, P; Gaudreau, P; Guilbault, L A; Morisset, J; Couture, Y; Petitclerc, D

    1994-10-01

    Forty-eight Holstein dairy heifers (98.9 kg BW; 3 mo old) were subjected for 246 d to twice-daily s.c. injections of saline (CTL) or human growth hormone-releasing hormone (GRH; 5 micrograms/kg BW) and to photoperiods of 8 h of light (L): 16 h of dark (D) or 16L:8D according to a 2 x 2 factorial arrangement of treatments. Jugular blood samples were collected from 16 heifers at 3, 4, 8, and 11 mo of age to monitor prolactin, growth hormone, and estradiol-17 beta. Plasma progesterone concentrations were monitored weekly in all heifers as an index of puberty (> 1 ng/mL). Growth hormone release was induced by GRH (P GRH heifers. However, GRH-induced GH response was less (P GRH, photoperiod, and days of treatment on GRH-induced GH response; AUC was greater in GRH-16L:8D than in GRH-8L:16D heifers at 3 mo but less at 8 mo of age. The PRL concentrations were similar for both photoperiods at 3 mo (36.4 vs 41.7 ng/mL) and 8 mo (16.2 vs 12.8 ng/mL) of age but were greater in 16L:8D vs 8L:16D heifers at 4 mo (18.4 vs 39.3 ng/mL) and 11 mo (26.3 vs 44.1 ng/mL) of age (photoperiod x day interaction, P GRH-treated heifers (271 vs 284 kg BW; GRH x photoperiod interaction, P = .10). In conclusion, GH response is maintained throughout 8 mo of GRH treatment, and a 16L:8D photoperiod will reduce age and weight at puberty in heifers. Furthermore, refractoriness to photoperiod-induced PRL changes was detected.

  3. Influence of Soft or Hard Floors before and after First Calving on Dairy Heifer Locomotion, Claw and Leg Health

    Directory of Open Access Journals (Sweden)

    Christer Bergsten

    2015-08-01

    Full Text Available Claw health, an important dairy cow welfare parameter, may be affected by early-life foot/leg stresses. To investigate this, groups of pregnant heifers were allocated to deep straw bedding (Soft or cubicles (Hard, both with scraped concrete feeding alleys. After the grazing season, they were re-housed in cubicle systems, half on slatted concrete (Hard and half on slatted rubber (Soft alleys. Claw measurements, contact area and pressure distribution claw/flooring, claw disorders and leg lesions were recorded at the start and end of each housing season. Locomotion and leg lesions were also scored monthly after calving. Prevalence of sole haemorrhages was higher among pregnant heifers in cubicles than in deep straw. After calving, first-calvers on Hard floors had higher odds for lameness (OR = 3.6; P < 0.01, sole haemorrhages/ulcers (OR = 2.2; P < 0.05, white-line haemorrhages (OR = 2.8; P < 0.01 and leg lesions (OR = 2.6; P < 0.02 than those on Soft floors. Lowest prevalence and severity of sole and white-line haemorrhages (non-significant in first-calvers was found in those on Soft floors and reared on Hard floors and the highest prevalence and severity on those on Hard floors reared on Soft floors. Soft flooring after calving is of most importance for healthy feet and legs.

  4. Influence of Soft or Hard Floors before and after First Calving on Dairy Heifer Locomotion, Claw and Leg Health.

    Science.gov (United States)

    Bergsten, Christer; Telezhenko, Evgenij; Ventorp, Michael

    2015-08-06

    Claw health, an important dairy cow welfare parameter, may be affected by early-life foot/leg stresses. To investigate this, groups of pregnant heifers were allocated to deep straw bedding (Soft) or cubicles (Hard), both with scraped concrete feeding alleys. After the grazing season, they were re-housed in cubicle systems, half on slatted concrete (Hard) and half on slatted rubber (Soft) alleys. Claw measurements, contact area and pressure distribution claw/flooring, claw disorders and leg lesions were recorded at the start and end of each housing season. Locomotion and leg lesions were also scored monthly after calving. Prevalence of sole haemorrhages was higher among pregnant heifers in cubicles than in deep straw. After calving, first-calvers on Hard floors had higher odds for lameness (OR = 3.6; P floors. Lowest prevalence and severity of sole and white-line haemorrhages (non-significant) in first-calvers was found in those on Soft floors and reared on Hard floors and the highest prevalence and severity on those on Hard floors reared on Soft floors. Soft flooring after calving is of most importance for healthy feet and legs.

  5. Efeitos da monensina no desempenho de bezerras leiteiras em crescimento Effects of monensin on growing dairy heifers performance

    Directory of Open Access Journals (Sweden)

    Márcia Saladini Vieira Salles

    2001-07-01

    Full Text Available Foi estudado o efeito da suplementação de monensina sobre o desempenho de 32 novilhas Holandesas em crescimento, com peso médio de 84 kg, durante quatro meses . Os animais suplementados com monensina apresentaram maior peso e perímetro torácico aos 90 e 120 dias de experimentação, maior ganho de peso, mostrando um valor de 26,56% maior do que os animais controle. Não foi observada diferença no comprimento corporal e glicose sangüínea, enquanto a altura na cernelha apresentou tendência a valores mais altos nos animais suplementados. Concluiu-se que a suplementação de monensina resultou em maior desenvolvimento dos animais, podendo proporcionar precocidade reprodutiva e produtiva de novilhas leiteiras de reposição.The performance of 32 growing Holstein heifers, with average weight of 84 kg and supplemented with monensin, during four months, was studied. The animals supplemented with monensin presented higher weight and hearth girth at 90 and 120 days of experiment, higher weight gain, with value of 26.56% superior than the control animals. No difference was observed for the corporal length, plasma glucose and the height values. The animals fed monensin presented higher height values. The animals supplemented with monensin showed better development. The use of monensin provided reproductive and productive precocity for the replacement dairy heifers.

  6. Use of a five-day progesterone-based timed AI protocol to determine if flunixin meglumine improves pregnancy per timed AI in dairy heifers.

    Science.gov (United States)

    Rabaglino, M B; Risco, C A; Thatcher, M-J; Lima, F; Santos, J E P; Thatcher, W W

    2010-06-01

    Two experiments were conducted to test the hypothesis that the 5 d Co-Synch + CIDR (Controlled Internal Drug Release insert containing progesterone) protocol could be applied as an efficient timed AI (TAI) protocol in dairy heifers, and that treatment with flunixin meglumine (FM) during the period of CL maintenance would increase pregnancy per TAI (P/TAI) and late survival of embryos. Objectives were: 1) in Experiment 1, to compare P/TAI with the 5 d Co-Synch+CIDR protocol to a PGF(2alpha)/GnRH protocol; and 2) in Experiment 2, to determine if FM administered 15.5 and 16 d after first TAI would increase P/TAI, using the 5 d Co-Synch+CIDR protocol with a new or previously used (5 d) CIDR insert. In Experiment 1, 248 heifers were assigned randomly to either the PGF(2alpha)/GnRH protocol (n=120) or the 5 d Co-Synch+CIDR protocol (n=128). Pregnancy per TAI did not differ between the 5 d Co-Synch+CIDR protocol (53.1%) and the PGF(2alpha)/GnRH protocol (45.8%; P=0.22). In Experiment 2, 325 heifers synchronized with the 5 d Co-Synch+CIDR protocol were assigned randomly to receive two injections of FM (FM group; n=158) at 15.5 and 16 d after TAI, or to remain as untreated controls (n=165). Pregnancy per TAI in Experiment 2 was 59.4 and 59.5% at 45 d for control and FM groups, respectively, with no differences between groups (P=0.83). The 5 d Co-Synch+CIDR protocol resulted in an acceptable P/TAI in dairy heifers. However, FM did not improve P/TAI in dairy heifers. 2010 Elsevier Inc. All rights reserved.

  7. The Effects of Dietary Phosphorus on the Growth Performance and Phosphorus Excretion of Dairy Heifers.

    Science.gov (United States)

    Zhang, B; Wang, C; Wei, Z H; Sun, H Z; Xu, G Z; Liu, J X; Liu, H Y

    2016-07-01

    The objective of this study was to investigate the effects of reducing dietary phosphorus (P) on the frame size, udder traits, blood parameters and nutrient digestibility coefficient in 8- to 10-month-old Holstein heifers. Forty-five heifers were divided into 15 blocks according to the mo of age and were randomly assigned one of three dietary treatments: 0.26% (low P [LP]), 0.36% (medium P [MP]), or 0.42% (high P [HP]) (dry matter basis). Samples were collected at the wk 1, 4, 8. The results show that low dietary P had no effect on body measurement. The blood P concentration decreased with decreasing dietary P (p<0.05), while the blood calcium content of LP was higher than that of the MP and HP groups (p<0.05), though still in the normal range. The serum contents of alkalinephosphatase, potassium, and magnesium were similar among the treatments. No differences were found in all nutrients' apparent digestibility coefficients with varied dietary P. However, with P diet decreased from HP to LP, the total fecal P and urine P concentration declined significantly, as did fecal water soluble P (p<0.05). In conclusion, reducing the dietary P from 0.42% to 0.26% did not negatively affect the heifers' growth performance but did significantly lessen manure P excretion into the environment.

  8. Comparison of 4- versus 5-day Co-Synch + controlled internal drug release (CIDR) + timed artificial insemination protocols in dairy heifers.

    Science.gov (United States)

    Palomares, Roberto A; Fishman, Heidi J; Jones, Arthur L; Ferrer, Maria S; Jenerette, Mathews; Vaughn, Aimee

    2015-10-01

    The objective of this study was to compare the pregnancy rate after timed artificial insemination (P/TAI) in dairy heifers treated with 4- versus 5-day Co-Synch + controlled internal drug release (CIDR) protocols. A total of 120 Holstein heifers were randomly assigned to one of two groups. The heifers received an intravaginal CIDR insert containing 1.38 g of progesterone for 4 days (Monday-Friday 4-day Co-Synch + CIDR; n = 60) or 5 days (5-day Co-Synch + CIDR; n = 60). At the time of CIDR removal, 25 mg of PGF2α was injected intramuscularly, and 72 hours after CIDR removal, the heifers received 100 μg of GnRH intramuscularly and were artificially inseminated. Artificial insemination was performed by an experienced technician, using commercial frozen-thawed semen from a single sire. Pregnancy diagnosis was performed by ultrasonography per rectum 32 days after TAI. Categorical data were analyzed using proc logistic and the chi-square test, whereas continuous variables were analyzed using the t-test of Statistical Analysis Systems. Heifers in the 4-day Co-Synch + CIDR group had an acceptable P/TAI32 (55.0%, 33 of 60), which was not different (P = 0.35) from that observed in the 5-day Co-Synch + CIDR group (63.3%, 38 of 60). Progesterone concentration at CIDR insertion or estradiol concentration at TAI did not influence the pregnancy outcomes. Interestingly, estradiol concentration at TAI was greater in the 4-day Co-Synch + CIDR group compared to the 5-day Co-Synch + CIDR group (P < 0.01). In conclusion, the Monday to Friday 4-day Co-Synch + CIDR protocol resulted in adequate P/TAI in dairy heifers, which was similar to that of the 5-day Co-Synch + CIDR protocol. This novel protocol might represent a promising hormonal treatment for TAI in dairy heifers, facilitating their reproductive management routine, while maintaining an adequate fertility.

  9. Vaccination of Heifers with Anaflatoxin Improves the Reduction of Aflatoxin B1 Carry Over in Milk of Lactating Dairy Cows

    Science.gov (United States)

    Giovati, Laura; Gallo, Antonio; Masoero, Francesco; Cerioli, Carla; Ciociola, Tecla; Conti, Stefania; Magliani, Walter; Polonelli, Luciano

    2014-01-01

    It was previously reported that injection of anaflatoxin B1 (AnAFB1) conjugated to keyhole limpet hemocyanin (KLH), together with Freund's adjuvant, was effective in inducing in cows a long lasting titer of anti-aflatoxin B1 (AFB1) antibodies (Abs), cross-reacting with other aflatoxins, which were able to hinder, proportionally to their titer, the secretion of aflatoxin M1 (AFM1) into the milk of cows continuously fed with AFB1. According to anti-AFB1 Ab titer, 50% of the vaccinated cows were recognized as high responder animals. In an attempt to prepare a more effective formulation for vaccination of cows, it was compared the immunogenicity, in Holstein Friesian heifers, of AnAFB1 covalently conjugated to KLH or to recombinant diphtheria toxin (CRM197) molecules, and injected together with various adjuvants. This study demonstrated that injection of AnAFB1 conjugated to KLH and mixed with complete (priming) and incomplete Freund's adjuvant (boosters), as in the previous schedule of immunization, was the most effective regimen for inducing Ab responses against AFB1, although pre-calving administration could increase the effectiveness of vaccination, resulting in 100% high responder animals. After one booster dose at the beginning of the milk production cycle, anti-AFB1 Ab titers were comparable to those recorded at the end of the immunization schedule, and proved to be effective in reducing significantly AFB1 carry over, as AFM1, from feed to milk. Pre-calving vaccination of dairy heifers with conjugated AnAFB1, adjuvated with complete and incomplete Freund's adjuvant, may represent the most effective tool for preventing the public health hazard constituted by milk and cheese contaminated with aflatoxins. PMID:24714096

  10. Vaccination of heifers with anaflatoxin improves the reduction of aflatoxin b1 carry over in milk of lactating dairy cows.

    Science.gov (United States)

    Giovati, Laura; Gallo, Antonio; Masoero, Francesco; Cerioli, Carla; Ciociola, Tecla; Conti, Stefania; Magliani, Walter; Polonelli, Luciano

    2014-01-01

    It was previously reported that injection of anaflatoxin B1 (AnAFB1) conjugated to keyhole limpet hemocyanin (KLH), together with Freund's adjuvant, was effective in inducing in cows a long lasting titer of anti-aflatoxin B1 (AFB1) antibodies (Abs), cross-reacting with other aflatoxins, which were able to hinder, proportionally to their titer, the secretion of aflatoxin M1 (AFM1) into the milk of cows continuously fed with AFB1. According to anti-AFB1 Ab titer, 50% of the vaccinated cows were recognized as high responder animals. In an attempt to prepare a more effective formulation for vaccination of cows, it was compared the immunogenicity, in Holstein Friesian heifers, of AnAFB1 covalently conjugated to KLH or to recombinant diphtheria toxin (CRM197) molecules, and injected together with various adjuvants. This study demonstrated that injection of AnAFB1 conjugated to KLH and mixed with complete (priming) and incomplete Freund's adjuvant (boosters), as in the previous schedule of immunization, was the most effective regimen for inducing Ab responses against AFB1, although pre-calving administration could increase the effectiveness of vaccination, resulting in 100% high responder animals. After one booster dose at the beginning of the milk production cycle, anti-AFB1 Ab titers were comparable to those recorded at the end of the immunization schedule, and proved to be effective in reducing significantly AFB1 carry over, as AFM1, from feed to milk. Pre-calving vaccination of dairy heifers with conjugated AnAFB1, adjuvated with complete and incomplete Freund's adjuvant, may represent the most effective tool for preventing the public health hazard constituted by milk and cheese contaminated with aflatoxins.

  11. Progesterone (CIDR)-based timed AI protocols using GnRH, porcine LH or estradiol cypionate for dairy heifers: ovarian and endocrine responses and pregnancy rates.

    Science.gov (United States)

    Ambrose, J D; Kastelic, J P; Rajamahendran, R; Aali, M; Dinn, N

    2005-10-15

    The overall objective was to compare the efficacy of GnRH, porcine LH (pLH) and estradiol cypionate (ECP), in a modified Ovsynch/fixed-time AI (FTAI) protocol that included a controlled internal drug [progesterone] release (CIDR) device. In Experiment 1, heifers received a CIDR on Day -10, and PGF (25mg) on Day -3. At CIDR insertion, heifers received 100 microg of GnRH (n=6), 0.5mg of ECP (n=6), 5.0mg of pLH (n=6) or 2 mL of saline (n=7); these treatments were repeated on Day -1, except for ECP, that was repeated on Day -2, concurrent with CIDR-removal. The 5.0 mg pLH was the least effective with a longer interval to ovulation than the other groups combined (102 versus 64 h; PpLH compared to all other groups (4.5 versus 10.3 ng/mL; PpLH (n=6; pLH-low), 25.0 mg pLH (n=6, pLH-high), or 100 microg GnRH (n=5; control). Heifers in the pLH-high group had greater (PpLH treatments did not differ (P>0.10). Area under the curve for LH (ng/32 h) was at least 50% greater (PpLH-treated heifers compared to GnRH-treated heifers (mean, 41.3, 56.3 and 20.3 for pLH-low, pLH-high and GnRH, respectively). Ovulation occurred in 15 of 17 heifers. Progesterone concentrations were higher on Days 9 and 14 in heifers given 25mg of pLH, suggesting enhanced CL function. In Experiment 3, 240 heifers were assigned to CIDR-based Ovsynch/FTAI protocols. The first and second hormonal treatments (with an intervening PGF treatment on Day -3) were GnRH/GnRH (100 microg), ECP/ECP (0.5 mg), pLH/pLH (12.5 mg) or GnRH/ECP, respectively; pregnancy rates were 58.7, 66.1, 45.9 and 48.3%, respectively (ECP/ECP>both pLH/pLH and GnRH/ECP; Pdairy heifers bred to Ovsynch/FTAI in the absence of a CIDR.

  12. Evaluation of a strategic deworming program in dairy heifers in Quebec based on the use of moxidectin, an endectocide with a long persistency.

    Science.gov (United States)

    Elsener, J; Villeneuve, A; DesCôteaux, L

    2001-01-01

    Two different deworming strategies based on the use of moxidectin, a broad spectrum endectocide with persistency against Ostertagia ostertagi, were evaluated in grazing dairy heifers. Eighty-four heifers unexposed to parasitic infection were randomly allocated to 3 different groups: untreated (Group 1), treated at 3 and 10 weeks after turnout with 0.5 mg/kg/body weight (BW) of topical moxidectin (Group 2), or treated at turnout and 10 weeks later with 0.5 mg/kg/BW of topical moxidectin (Group 3). The heifers were turned out on June 6 (Day 0) to a naturally contaminated pasture divided into 3 sections by an electrical fence. Each group of heifers was put on a different section of pasture. The trial ended when they were housed on October 29 (Day 143). The results of this experiment confirmed the beneficial effect of 2 strategic treatments with moxidectin pour-on under field conditions in Quebec. The parasitological parameters showed a statistical difference in terms of mean fecal egg counts between treated and control groups (ANOVA, P < or = 0.006). After turnout, pasture larval counts were consistently higher for Group 1 compared with counts for Group 2 or 3. All heifer groups gained weight during the trial period, but the weight gain profile of both treated groups was significantly higher than that of the untreated controls (ANOVA, P < 0.03). During the trial period, Group 2 and Group 3 gained 77.7 kg BW and 73.2 kg BW, respectively, while Group 1 gained only 57.9 kg BW, despite the fact that heifers of Group 1 received a greater quantity of supplementary feed while on pasture.

  13. Effects of testosterone and 5alpha-dihydrotestosterone on luteal lifespan in dairy heifers.

    Science.gov (United States)

    Silvia, W J; Jacobs, A L; Hayes, S H

    1989-11-01

    Endogenous concentrations of testosterone increase approximately 7 d prior to estrus in cattle and goats. Inhibition of testosterone synthesis results in a delay of luteal regression in both species. The purpose of this experiment was to determine if treatment with testosterone or 5alpha-dihydrotestosterone (DHT), 2 to 6 d prior to the endogenous rise in testosterone, would result in premature luteal regression. Sixteen heifers were randomly assigned to one of three treatment groups: 1) Control (n = 6); 2) testosterone (100 mug, n = 5); or 3) DHT (100 mug, n = 5). Each heifer received a single injection of the appropriate steriod on Day 8, 9, 10, 11 or 12 post estrus. Jugular venous blood samples were collected at frequent intervals for 24 h to quantify testosterone, and then daily for 14 d to quantify progesterone. Concentrations of testosterone increased within 15 min of injection of testosterone, and reached a maximum at 30 min. Concentrations were maintained at > 2 ng/ml throughout the first 24 h after injection. Based on concentrations of progesterone, neither androgen had any effect on the lifespan of the corpus luteum or the level of luteal function.

  14. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review.

    Science.gov (United States)

    Lohakare, J D; Südekum, K-H; Pattanaik, A K

    2012-09-01

    This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only reduces the age of sexual maturity but also lowers the time period of attaining the age of first calving. However, high energy diets may cause undesirable fat deposition thereby affecting future milk yield potential. Discrepancies exist whether overfed or overweight heifers at puberty can influence the mammary development and future milk yield potential and performance. The data on post-pubertal nutritional management suggested that body weight at calving and post-pubertal growth rate is important in first lactation milk yield. There is a continuous research need for strategic feeding that accelerates growth of dairy heifers without reduction in subsequent production. Nutritional management from birth, across puberty and during pregnancy is critical for mammary growth and for producing a successful cow. This review will mostly highlight studies carried out on dairy breeds and possible available opportunities to manipulate nutritional status from birth until age at first calving.

  15. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review

    Directory of Open Access Journals (Sweden)

    J. D. Lohakare

    2012-09-01

    Full Text Available This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only reduces the age of sexual maturity but also lowers the time period of attaining the age of first calving. However, high energy diets may cause undesirable fat deposition thereby affecting future milk yield potential. Discrepancies exist whether overfed or overweight heifers at puberty can influence the mammary development and future milk yield potential and performance. The data on post-pubertal nutritional management suggested that body weight at calving and post-pubertal growth rate is important in first lactation milk yield. There is a continuous research need for strategic feeding that accelerates growth of dairy heifers without reduction in subsequent production. Nutritional management from birth, across puberty and during pregnancy is critical for mammary growth and for producing a successful cow. This review will mostly highlight studies carried out on dairy breeds and possible available opportunities to manipulate nutritional status from birth until age at first calving.

  16. Effect of limit feeding high- and low-concentrate diets with Saccharomyces cerevisiae on digestibility and on dairy heifer growth and first-lactation performance.

    Science.gov (United States)

    Lascano, G J; Zanton, G I; Suarez-Mena, F X; Heinrichs, A J

    2009-10-01

    Growth and digestibility were examined for heifers limit fed high- (HC; 60%) and low-concentrate (LC; 20%) diets with or without yeast culture (YC) addition in 2 experiments. A third experiment was undertaken to monitor first-lactation production of heifers limit fed HC or LC diets. In experiment 1, 32 Holstein heifers were individually fed at controlled intakes for 133 d to maintain a targeted average daily gain of 0.80 kg/d for all 4 treatments [HC; LC with and without Saccharomyces cerevisiae; Yea-Sacc(1026) (Alltech Inc., Nicholasville, KY), 1 g/kg as fed]. Targeted average daily gain was achieved for all treatments during the individual feeding period (0.80 +/- 0.01 kg/d). Average dry matter intake needed to maintain constant gain was slightly reduced for HC and YC treatments. Reduced dry matter intake and similar targeted average daily gain resulted in a tendency for improved feed efficiency of HC-fed heifers. Skeletal measurements and targeted average daily gain were not affected by concentrate level or YC. The objective of experiment 2 was to elucidate effects of concentrate level and YC on nutrient digestibility. Four young (284.35 +/- 4.51 d) and 4 older (410.28 +/- 2.14 d) heifers were allocated to the 4 treatments used in experiment 1. Heifers fed the HC diet had increased dry matter digestibility (75.67 vs.72.96 +/- 0.72%), and YC addition increased dry matter digestibility (74.97 vs. 73.65 +/- 0.71%). Intake of N and apparent N digestibility were similar for all treatments. High-concentrate diets and YC addition decreased wet and dry matter output of feces. Urine excretion was not different; therefore, total manure output was lower for HC-fed heifers as compared with LC-fed heifers. Results suggest that HC diets can improve feed efficiency without affecting growth when limit fed to dairy heifers. Yeast culture increased dry matter digestibility in HC- and LC-fed heifers; HC diets were more digestible and reduced fecal output, with YC enhancing this

  17. Corralling versus broadcasting dairy heifer manure: volatilization, leaching, and mineralizable N

    Science.gov (United States)

    Because they lack sufficient manure storage, a majority of dairy farmers in the northern USA spread livestock manure as frequent broadcast applications. Corralling livestock in the fields could achieve desired application rates, while reducing N losses and labor. We conducted two field experiments o...

  18. Digestibility of whole-crop barley and oat silages in dairy heifers.

    Science.gov (United States)

    Wallsten, J; Bertilsson, J; Nadeau, E; Martinsson, K

    2010-03-01

    This study evaluated the digestibility of whole-crop cereal silage (WCCS) made from oats and six-rowed barley harvested at the heading, early milk and early dough stages, and two-rowed barley harvested at the early milk and early dough stages of maturity. The eight WCCSs were fed to 32 Swedish Red heifers in a changeover design over three periods of 28 days each. The heifers were first fed ad libitum for 17 days and then at 0.95 of ad libitum for 11 days of each period. During the last 5 days all faeces and orts were collected to determine the digestibility of the silages. Only the maturity stage effect was significant for the WCCS organic matter (OM) digestibility and the average OM digestibility was higher at the heading stage (698 g/kg) than at early milk (647 g/kg) and early dough (652 g/kg) stages of maturity. For neutral detergent fibre (NDF) digestibility the crop × maturity stage effect was significant. The NDF digestibility decreased from the heading to the early milk stage for both six-rowed barley (746 to 607 g/kg) and oats (698 to 596 g/kg). There was no further significant decrease in NDF digestibility for six-rowed barley at the early dough stage (577 g/kg), but for two-rowed barley it decreased from the early milk (682 g/kg) to the early dough (573 g/kg) stage, and also for oats the NDF digestibility was lowest at the early dough stage (507 g/kg). The decrease in NDF digestibility during maturation was to a large extent compensated by an increase in starch concentration in the crops. The starch digestibility was lower for six-rowed barley at early dough stage (948 g/kg) than at early milk stage (977 g/kg), and was also lower compared with oats (979 g/kg) at early dough stage. The average crude protein (CP) digestibility was higher at the heading (646 g/kg) and the early milk (642 g/kg) stages than at the early dough stage (599 g/kg), and oats had higher average CP digestibility (650 g/kg) than six-rowed (613 g/kg) and two-rowed (624 g/kg) barley

  19. Effects of BST and high energy diet on gene expression in mammary parenchyma of dairy heifers

    Directory of Open Access Journals (Sweden)

    Betina Joyce Lew

    2013-07-01

    Full Text Available The objective of this study was to determine the effects of dietary energy and recombinant bovine somatotropin (bST injection to identify genes that might control mammogenesis. Total RNA was extracted from the parenchymal tissue of 32 heifers randomly assigned to one of four treatments: two diets (a standard diet and a high energy, high protein diet, each with or without bST. To perform microarray experiments, RNA samples were pooled (2 animals/pool before reverse transcription and labeling with Cy3 or Cy5. A 4-node loop design was used to examine the differential gene expression among treatments using a bovine-specific cDNA microarray (National Bovine Functional Genomics Consortium Library, NBFGC containing 18,263 unique expressed sequence tags (EST. Significance levels of differential gene expression among treatments were assessed using a mixed model approach. Injection of bST altered the expression of 12 % of the genes on NBFGC slide related to tissue development, whereas 6% were altered by diet. Administration of bST increases the expression of genes positively related to cell proliferation and mammary parenchyma to a greater extent than a high energy diet.

  20. Effects of grazing system on production and parasitism of dairy breed heifers and steers grazing wet marginal grasslands

    DEFF Research Database (Denmark)

    Kristensen, Troels; Thamsborg, S.M.; Andersen, Refsgaard;

    2006-01-01

    Production and endoparasitism of first grazing season Holstein heifers and steers were investigated over two grazing seasons. Studies were conducted on low-lying peaty soil. In year 2000, 40 animals were included in a 2x2 factorial, replicated experiment with two sexes (steers v. heifers) and two...

  1. Pathways towards to improve the feasibility of dairy pastoral system in La Pampa (Argentine

    Directory of Open Access Journals (Sweden)

    Elena Angón

    2015-11-01

    Full Text Available Over the last decade, pastoral systems have been intensified in response to an increasing demand for meat and milk, by generating environmental and social problems due to its high dependence on external inputs. The objective of this research was to analyze the economic feasibility of dairy pastoral system in La Pampa (Argentina. The main successful factors were identified through technical efficiency analysis, and subsequently improvement actions were suggested. The technique data envelopment analysis creates efficiency indexes by comparing the performance of each farm with the best practice, which defines the production frontier. The farms were classified attending to two criteria: first, the level of efficiency, second, the regular use of supplementation feed. The results showed that about 40% of the farms were efficient and the efficiency rate of the farms without supplementary feed was 80%. A 70% of the farms uses their own grassland resources adjusting milk yield to the capacity of the pasture. The technical efficiency for this group is 14% higher than the rest. Inefficient farms can adopt different strategies to enhance by practicing benchmarking. One of the examples studied shows two ways to do it: on the one hand the extensification by producing at a minimum cost; on the other hand, the technification, linked to the increase of stocking rate and the use of strategic supplementation. Finally, small changes in the management of the farms positively impact on performance, use of resources, and the sustainability of the system.

  2. Precision-feeding dairy heifers a high rumen-degradable protein diet with different proportions of dietary fiber and forage-to-concentrate ratios.

    Science.gov (United States)

    Lascano, G J; Koch, L E; Heinrichs, A J

    2016-09-01

    The objective of this experiment was to determine the effects of feeding a high-rumen-degradable protein (RDP) diet when dietary fiber content is manipulated within differing forage-to-concentrate ratio (F:C) on nutrient utilization of precision-fed dairy heifers. Six cannulated Holstein heifers (486.98±15.07kg of body weight) were randomly assigned to 2 F:C, low- (45% forage; LF) and high-forage (90% forage; HF) diets and to a fiber proportion sequence [33% grass hay and wheat straw (HS), 67% corn silage (CS; low fiber); 50% HS, 50% CS (medium fiber); and 67% HS, 33% CS (high fiber)] within forage proportion administered according to a split-plot, 3×3 Latin square design (16-d periods). Heifers fed LF had greater apparent total-tract organic matter digestibility coefficients (dC), neutral detergent fiber, and cellulose than those fed LC diets. Substituting CS with HS resulted in a linear reduction in dry matter, organic matter, and cellulose dC. Nitrogen dC was not different between F:C or with increasing proportions of HS in diets, but N retention tended to decrease linearly as HS was increased in the diets. Predicted microbial protein flow to the duodenum decreased linearly with HS addition and protozoa numbers HS interacted linearly, exhibiting a decrease as HS increased for LF, whereas no effects were observed for HF. Blood urea N increased linearly as HS was incorporated. The LF-fed heifers had a greater ruminal volatile fatty acids concentration. We noted a tendency for a greater dry matter, and a significantly higher liquid fraction turnover rate for HF diets. There was a linear numerical increase in the liquid and solid fraction turnover rate as fiber was added to the diets. Rumen fermentation parameters and fractional passages (solid and liquid) rates support the reduction in dC, N retention, and microbial protein synthesis observed as more dietary fiber is added to the rations of dairy heifers precision-fed a constant proportion of rumen

  3. Performance of dairy heifers raised on Xaraés palissadgrass (Brachiaria brizantha cv. Xaraés pasture supplemented with two types of mineral mixture

    Directory of Open Access Journals (Sweden)

    Carlos Augusto B. de Carvalho

    2014-01-01

    Full Text Available The effects of selective (e.g. mineral supplement formulated on the basis of nutritional and clinical examination of the herd or commercial mineral supplementation of crossbred dairy heifers (Holstein-Mantiqueira, on daily weight gain (DWG, body condition score (BCS, age at first mating (AFM and the intake of mineral mixture (IMM managed on Xaraés palissadgrass pasture (Brachiaria brizantha cv. Xaraés were evaluated from February 2006 to March 2008. Structural characteristics, forage allowance and nutritional value of Xaraés palissadgrass were also evaluated. The structural variables of pasture, allowances and nutritive value of forage, besides the DWG were only affected (p<0.05 by season, with highest results for spring and summer. Throughout the experimental period (730 days, no sign of mineral deficiency was detected in heifers that ingested the selective supplement. The DWG and AFM were not influenced by the mineral mixture offered (0.52 and 0.33 kg/day during the spring/summer and in fall/winter for DWG, respectively, and 813 days of AFM. The IMM was higher for commercial mineral mixture than for selective (61.6 and 51.0g/day respectively. The BCS was slightly higher for selective (3.17 than for the commercial (3.02 mineral mixture. Thus, the selective mineral supplement was a strategy to prevent mineral deficiency in this herd and resulted in similar performance at lower costs (e.g. due to less IMM of crossbred heifers when compared with the commercial mineral supplementation.

  4. Randomised clinical trial evaluating the effect of different timing and number of fixed timed artificial inseminations, following a seven-day progesterone-based protocol, on pregnancy outcomes in UK dairy heifers.

    Science.gov (United States)

    Walsh, John Paul; Coates, Amy; Lima, Fabio; Smith, Rob; Oikonomou, Georgios

    2017-09-25

    The objective of this study was to determine the effect on pregnancy outcome of either inseminating heifers twice (at 48 and 72 hours after withdrawal of a controlled internal drug release insert (CIDR) containing progesterone) or once (56 hours after CIDR withdrawal) following a seven-day CIDR synchronisation protocol. Dairy heifers (n=267) from five farms, with an age range of 388-736 days, were randomly assigned to one of two treatment groups (group A heifers were inseminated twice; group B heifers were inseminated once). Both groups received a CIDR on day (D) 0 and an intramuscular injection of d-cloprostenol on D6; the CIDR was withdrawn on D7. Measurements of withers height, body condition score and hearth girth (used to estimate weight) were taken on D0. The diameter of the largest follicles and corpora lutea was recorded on both D0 and D6. Data were analysed with the use of multivariable logistic regression modelling. Treatment group and farm were not statistically significantly associated with pregnancy per treatment (P/T). Age and dominant follicle size on D6 were significantly associated with P/T. Heifers with the largest dominant follicle sizes (16-22 mm) were 5.54 times less likely to be pregnant than those heifers with the smallest dominant follicles (8-10 mm) on D6. It was shown that the cost associated with inseminating heifers twice after a seven-day CIDR synchronisation protocol is not justified. © British Veterinary Association (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  5. Introducing heifers to freestall housing.

    Science.gov (United States)

    von Keyserlingk, M A G; Cunha, G E; Fregonesi, J A; Weary, D M

    2011-04-01

    Little work to date has assessed how dairy cattle respond when first introduced to freestall housing. In this study we carried out 2 experiments. The aim of experiment 1 was to assess the behavioral responses of naïve heifers to pens fitted with freestalls. Holstein heifers (n=7 groups, each containing 3 heifers, 3 mo of age), with no previous experience with freestalls, were initially housed on a sawdust bedded pack and fed through a fixed feed barrier for at least 6 wk and then moved to a freestall pen fitted with a head-locking feed barrier. When kept on the bedded pack, the heifers' lying time averaged 14.2 h/d. On the day heifers were moved to the freestall pen, lying times declined by 2.9 h, but recovered on the following days. The time spent lying down on the barn floor (i.e., outside the lying area) increased by 2.5 h on the day heifers were introduced to freestalls and remained higher during subsequent days. Heifers spent 46 min/d less time feeding on the day they were switched to the head-locking barrier, but recovered on the following days. In experiment 2 we assessed the behavioral responses of naïve heifers introduced to pens fitted with freestalls with or without a neck rail. Holstein heifers (n=12 groups, each containing 2 heifers, 3 mo of age), with no previous experience with freestalls, were initially housed on a sawdust bedded pack and then moved to a freestall pen with or without neck rails. Heifers spent 4.2 h/d less time lying down in the 24 h following introduction into the freestall pen; the neck rail treatment had no effect on lying time but heifers spent more time standing with just their front 2 hooves in the stall when a neck rail was in the stall. In summary, lying and feeding behavior of naïve heifers is altered following introduction to new housing. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Endocrine Profiles, Haematology and Pregnancy Outcomes of Late Pregnant Holstein Dairy Heifers Sired by Bulls Giving a High or Low Incidence of Stillbirth

    Directory of Open Access Journals (Sweden)

    Kindahl H

    2004-03-01

    Full Text Available The high incidence of stillbirth in Swedish Holstein heifers has increased continuously during the last 15 years to an average of 11% today. The pathological reasons behind the increased incidence of stillbirth are unknown. The present experiment was undertaken to investigate possible causes of stillbirth and to study possible physiological markers for predicting stillbirth. Twenty Swedish Holstein dairy heifers sired by bulls with breeding values for a high risk of stillbirth (n = 12 (experimental group and a low risk of stillbirth (n = 8 (control group, group B were selected based on information in the Swedish AI-data base. The experimental group consisted of 2 subgroups of heifers (groups A1 and A2 inseminated with 2 different bulls with 3.5% and 9% higher stillbirth rates than the average, and the control group consisted of heifers pregnant with 5 different bulls with 0%–6% lower stillbirth rates than the average. The bull used for group A1 had also calving difficulties due to large calves as compared to the bull in group A2 showing no calving difficulties. The heifers were supervised from 6–7 months of pregnancy up to birth, and the pregnancies and parturitions were compared between groups regarding hormonal levels, haematology, placental characteristics and calf viability. In group A1, 1 stillborn, 1 weak and 4 normal calves were recorded. In group A2, 2 stillborn and 4 normal calves were registered. All animals in the control group gave birth to a normal living calf without any assistance. The weak calf showed deviating profiles of body temperature, saturated oxygen and heart rates, compared with the normal living calves. No differences of the placentome thickness, measured in vivo by ultrasonography were seen between the groups. The number of leukocytes and differential cell counts in groups A1 and A2 followed the profiles found in the control group. In group A1, a slight decrease of oestrone sulphate (E1SO4 levels was found in the

  7. Cellular proliferation rate and insulin-like growth factor binding protein (IGFBP)-2 and IGFBP-3 and estradiol receptor alpha expression in the mammary gland of dairy heifers naturally infected with gastrointestinal nematodes during development.

    Science.gov (United States)

    Perri, A F; Dallard, B E; Baravalle, C; Licoff, N; Formía, N; Ortega, H H; Becú-Villalobos, D; Mejia, M E; Lacau-Mengido, I M

    2014-01-01

    Mammary ductal morphogenesis during prepuberty occurs mainly in response to insulin-like growth factor-1 (IGF-1) and estradiol stimulation. Dairy heifers infected with gastrointestinal nematodes have reduced IGF-1 levels, accompanied by reduced growth rate, delayed puberty onset, and lower parenchyma-stroma relationship in their mammary glands. Immunohistochemical studies were undertaken to determine variations in cell division rate, IGF-1 system components, and estradiol receptors (ESR) during peripubertal development in the mammary glands of antiparasitic-treated and untreated Holstein heifers naturally infected with gastrointestinal nematodes. Mammary biopsies were taken at 20, 30, 40, and 70 wk of age. Proliferating cell nuclear antigen immunolabeling, evident in nuclei, tended to be higher in the parenchyma of the glands from treated heifers than in those from untreated. Insulin-like growth factor binding proteins (IGFBP) type 2 and type 3 immunolabeling was cytoplasmic and was evident in stroma and parenchyma. The IGFBP2-labeled area was lower in treated than in untreated heifers. In the treated group, a maximal expression of this protein was seen at 40 wk of age, whereas in the untreated group the labeling remained constant. No differences were observed for IGFBP3 between treatment groups or during development. Immunolabeling for α ESR (ESR1) was evident in parenchymal nuclei and was higher in treated than in untreated heifers. In the treated group, ESR1 peaked at 30 wk of age and then decreased. These results demonstrate that the parasite burden in young heifers negatively influence mammary gland development, affecting cell division rate and parameters related to estradiol and IGF-1 signaling in the gland.

  8. Efficacy of polyethylene glycol-conjugated bovine granulocyte colony-stimulating factor for reducing the incidence of naturally occurring clinical mastitis in periparturient dairy cows and heifers.

    Science.gov (United States)

    Hassfurther, Renee L; TerHune, Terry N; Canning, Peter C

    2015-03-01

    To evaluate effects of various doses of polyethylene glycol (PEG)-conjugated bovine granulocyte colony-stimulating factor (bG-CSF) on the incidence of naturally occurring clinical mastitis in periparturient dairy cattle. 211 periparturient Holstein cows and heifers. Approximately 7 days before the anticipated date of parturition (day of parturition = day 0), healthy cattle received SC injections of sterile saline (0.9% NaCl) solution (control treatment) or PEG-bG-CSF at 5, 10, or 20 μg/kg. Cattle were commingled and housed in a pen with dirt flooring, which was kept wet to maximize the incidence of naturally occurring clinical mastitis. Within 24 hours after parturition, each animal again received the assigned treatment. Mammary glands and milk were visually scored for abnormalities twice daily for 28 days after parturition. Milk samples were aseptically collected from mammary glands with an abnormal appearance or abnormal milk and submitted for microbial culture. Daily milk production was recorded, and milk composition was assessed on days 3, 5, 7, and 10. Cattle treated with PEG-bG-CSF at 10 and 20 μg/kg had significantly fewer cases of clinical mastitis (9/54 and 5/53, respectively), compared with control cattle (18/53). Administration of PEG -bG-CSF did not significantly affect daily milk production or milk composition. Results suggested that PEG-bG-CSF was effective for reducing the incidence of naturally occurring clinical mastitis in periparturient dairy cattle. Further investigations of the use of PEG-bG-CSF as a potential preventative intervention should be conducted.

  9. Supplementation with different energy and protein sources on the feeding behavior and performance of dairy heifers grazing Marandu during the dry season

    Directory of Open Access Journals (Sweden)

    Ricardo Dias Signoretti

    2012-02-01

    Full Text Available This study aimed to evaluate the effect of supplementation different energy and protein sources in the dry season of the year, on body development and diurnal feeding behavior of crossbred Gir x Holstein dairy heifers 12.8 ± 4.6 months old, 215.50 ± 43.2 kg average body weight were distributed in Brachiaria brizantha cv. Marandu pasture with supplements being offered daily in proportion of 0.75% of the body weight. A completely randomized block design with a 2 x 2 factorial arrangement was used, with six replicates per treatment. Supplements contained whole soybean (WS or whole cottonseed (WC as the protein sources and citrus pulp (CPU or corn (C as the energy sources. Marandu grass pasture was managed according a rotational grazing system, six days grazing and 30 days of rest period. It was recorded the animals weight, height at withers, heart girt, rump length and corporal score after the grazing cycle. The considered behavioral variables were grazing time, ruminating time, idle time, trough time. No significant differences on the initial, heart girt, height at withers, rump length and corporal score final and initial to protein and energy sources. However, a significant effect was observed (P<0.05 in heifers supplemented with WC had greater final body weight and heart girt and average daily gain live weight (271.1 kg, 152.2 cm and 0.382 kg/animal, respectively in comparison to those with WS (251.1 kg, 148.7 cm and 0.255 kg/animal, respectively. The CPU base supplement resulted in smaller grazing time and greater ruminating and idle time (P>0.05. The WS base supplemented animals had kept lesser time eating supplement in comparison to the WC base supplemented ones (P<0.05, with no variation in grazing, rumination or idle times regarding protein font (P>0.05. The hour of the day influenced all the considered behaviors (P<0.01.

  10. Serological response to administration of Brucella abortus strain RB51 vaccine in beef and dairy heifers, using needle-free and standard needle-based injection systems

    Science.gov (United States)

    The purpose of this study was to compare immunologic responses of heifers vaccinated with 10**10 colony-forming units (CFU) of Brucella abortus strain RB51 (SRB51) by standard needle-and-syringe system or a needle-free injection system. Heifers were randomly assigned to control and vaccination gro...

  11. Effects of feeding alfalfa stemlage or wheat straw for dietary energy dilution on growth performance and sorting behaviors of holstein dairy heifers

    Science.gov (United States)

    Feeding high-quality forage diets may lead to excessive weight gains and over-conditioning for pregnant Holstein heifers. Restriction of energy density and dry matter intake (DMI) by heifers by using low-energy forages, such as straw, is a good approach for controlling this problem. Alfalfa stems co...

  12. Economic and social considerations of breeding for polled dairy cows versus dehorning

    Science.gov (United States)

    Dairy producers today face labor, equipment, and medical costs associated with dehorning heifers. Further, complications requiring veterinary intervention occur with some probability. The objective of this work is to develop preliminary cost estimates of selecting for polled dairy heifers. Stochasti...

  13. Oral Administration of Faecalibacterium prausnitzii Decreased the Incidence of Severe Diarrhea and Related Mortality Rate and Increased Weight Gain in Preweaned Dairy Heifers.

    Directory of Open Access Journals (Sweden)

    Carla Foditsch

    Full Text Available Probiotics are a promising alternative to improve food animal productivity and health. However, scientific evidence that specific microbes can be used to benefit animal health and performance is limited. The objective of this study was to evaluate the effects of administering a live culture of Faecalibacterium prausnitzii to newborn dairy calves on subsequent growth, health, and fecal microbiome. Initially, a safety trial was conducted using 30 newborn bull calves to assess potential adverse effects of the oral and rectal administration of F. prausnitzii to neonatal calves. No adverse reactions, such as increased body temperature or heart and respiratory rates, were observed after the administration of the treatments. All calves survived the experimental period, and there was no difference in fecal consistency score, attitude, appetite or dehydration between the treatment groups. The rectal route was not an efficient practice while the oral route ensures that the full dose is administered to the treated calves. Subsequently, a randomized field trial was completed in a commercial farm with preweaned calves. A total of 554 Holstein heifers were assigned to one of two treatment groups: treated calves (FPTRT and non-treated calves (control. Treated calves received two oral doses of F. prausnitzii, one at treatment assignment (1st week and another one week later. The FPTRT group presented significantly lower incidence of severe diarrhea (3.1% compared with the control group (6.8%. Treated calves also had lower mortality rate associated with severe diarrhea (1.5% compared to control calves (4.4%. Furthermore, FPTRT calves gained significantly more weight, 4.4 kg over the preweaning period, than controls calves. The relative abundance of F. prausnitzii in the fecal microbiota was significantly higher in the 3rd and 5th weeks of life of FPTRT calves than of the control calves, as revealed by sequencing of the 16S rRNA gene. Our findings showed that oral

  14. Effects of vitamin E supplementation on and the association of body condition score with changes in peroxidative biomarkers and antioxidants around calving in dairy heifers

    NARCIS (Netherlands)

    Dobbelaar, P.; Bouwstra, R.J.; Goselink, R.M.A.; Jorritsma, R.; Borne, van den J.J.G.C.; Jansen, E.H.J.M.

    2010-01-01

    The objective of this study was to investigate the effect of vitamin E supplementation on oxidative status in blood, liver, milk, and ovarian follicular fluid in periparturient heifers. Vitamin E supplementation started 8 wk before calving and continued until 8 wk postpartum. Grass silage was the ma

  15. Feeding fat from distillers dried grains with solubles to dairy heifers: III. Effects on long-term reproductive and lactation performance

    Science.gov (United States)

    During the prepubertal growth phase, 33 Holstein heifers (133 ± 18 d old) were used in a 24-week randomized complete block design. Treatments included: 1) a control diet (CON) containing ground corn (15.9% of DM) and soybean products (17.9%); 2) a low-fat diet (LFDG) formulated with 21.9% fat-extrac...

  16. Consumo, digestibilidade e desempenho de novilhas alimentadas com casca de café em substituição à silagem de milho Intake, digestibility and performance of dairy heifers fed coffee hulls replacing of corn silage

    Directory of Open Access Journals (Sweden)

    Rafael Monteiro Araújo Teixeira

    2007-08-01

    Full Text Available Objetivou-se avaliar a substituição da silagem de milho pela casca de café em dietas de novilhas leiteiras sobre os consumos, as digestibilidades aparentes totais dos nutrientes e o desempenho dos animais. Foram utilizadas 24 novilhas holandesas, puras e mestiças, distribuídas, de acordo com o peso inicial dos animais, em delineamento em blocos casualizados com quatro tratamentos (níveis de casca de café: 0,0; 7,0; 14,0 e 21,0% na base da MS total e seis repetições. Diariamente, todas as novilhas foram alimentadas com 2 kg de concentrado. Os consumos de MS aumentaram linearmente, enquanto os consumos de matéria natural (MN não foram influenciados pela inclusão de casca de café nas dietas. O aumento no consumo de MS foi de aproximadamente 20 g para cada unidade de casca de café adicionada na dieta (% MS e o consumo médio de MN foi de 13,84 kg/dia. As digestibilidades de MS, MO, PB, CT e FDN e a concentração de NDT das dietas reduziram linearmente com a substituição da silagem de milho pela casca de café, observando-se redução de 0,158 unidades percentuais na digestibilidade da MS para cada unidade de casca de café adicionada na dieta (% MS. A inclusão de casca de café afetou de modo negativo o ganho de peso, que reduziu linearmente (5,51 g de PV por unidade de casca de café adicionada a dieta conforme aumentaram os níveis de casca de café em substituição a silagem de milho. Em dietas para novilhas leiteiras, a casca de café pode substituir a silagem de milho em níveis de até 14% na MS total.The objective was to evaluate the replacement corn silage by coffee hulls in the diet on performance, total apparent digestibility of dairy heifers. Twenty-four dairy Holstein heifers, purebred and crossbred, were assigned, according to animal initial weight, to a randomized block design with four treatments (Coffee hulls levels: 0.0, 7.0, 14.0, and 21.0% DM basis and six replicates. All heifers were daily fed 2.0 kg

  17. Nutrition-induced Changes of Growth from Birth to First Calving and Its Impact on Mammary Development and First-lactation Milk Yield in Dairy Heifers: A Review

    OpenAIRE

    Lohakare, J. D.; Südekum, K.-H.; A. K. Pattanaik

    2012-01-01

    This review focuses on the nutritional effects from birth until age at first calving on growth, mammary developmental changes, and first-lactation milk yield in heifer calves. The advancement in the genetic potential and the nutritional requirements of the animals has hastened the growth rate. Genetic selection for high milk yield has suggested higher growth capacity and hence increasing nutritional inputs are required. Rapid rearing by feeding high energy or high concentrate diets not only r...

  18. Repellent effectiveness of seven plant essential oils, sunflower oil and natural insecticides against horn flies on pastured dairy cows and heifers.

    Science.gov (United States)

    Lachance, S; Grange, G

    2014-06-01

    Plant essential oils (basil, geranium, balsam fir, lavender, lemongrass, peppermint, pine and tea tree), mixed with either sunflower oil or ethyl alcohol, were applied at 5% concentrations to the sides of Holstein cattle. Pastured cattle treated with essential oils diluted in sunflower oil had less flies than the untreated control for a 24-h period. However, the essential oil treatments were not significantly different than the carrier oil alone. Barn-held heifers treated with essential oils and sunflower oil alone had significantly less flies than the untreated control for up to 8 h after treatment. Basil, geranium, lavender, lemongrass and peppermint repelled more flies than sunflower oil alone for a period ranging from 1.5 to 4 h after treatments applied to heifers. All essential oils repelled > 75% of the flies on the treated area for 6 and 8 h on pastured cows and indoor heifers, respectively. Geranium, lemongrass and peppermint stayed effective for a longer duration. Essential oils mixed with ethyl alcohol demonstrated less repellence than when mixed with the carrier oil. Safer's soap, natural pyrethrins without piperonyl butoxide and ethyl alcohol alone were not efficient at repelling flies. Essential oils could be formulated for use as fly repellents in livestock production.

  19. Effects of road transportation on metabolic and immunological responses in Holstein heifers.

    Science.gov (United States)

    Kang, Hyeok-Joong; Lee, In Kyu; Piao, Min-Yu; Kwak, Chae-Won; Gu, Min Jeong; Yun, Cheol Heui; Kim, Hyun-Jin; Ahn, Hyeon-Ju; Kim, Hee-Bal; Kim, Gyeom-Heon; Kim, Soo-Ki; Ko, Jong-Youl; Ha, Jong K; Baik, Myunggi

    2017-01-01

    This study examined the effects of road transportation on metabolic and immunological responses in dairy heifers. Twenty Holstein heifers in early pregnancy were divided into non-transported (NT; n = 7) and transported (T; n = 13) groups. Blood was collected before transportation (BT), immediately after transportation for 100 km (T1) and 200 km (T2), and 24 h after transportation (AT). The T heifers had higher (P  0.05) to the BT concentrations at 24 h AT in the T heifers. The granulocyte-to-lymphocyte ratio and the percentage of monocytes were higher (P transportation stress increased the numbers of innate immune cells. T heifers had higher (P transportation increased cortisol secretion and was correlated with increased metabolic responses and up-regulation of peripheral innate immune cells in dairy heifers.

  20. Effects of feeding level and NDF content of grass-clover silages on chewing activity, fecal particle size and NDF digestibility in dairy heifers.

    Science.gov (United States)

    Schulze, A K S; Weisbjerg, M R; Nørgaard, P

    2014-12-01

    The objective of this study was to assess effects of feed intake and NDF content of highly digestible grass-clover silage on chewing behavior, fecal particle size distribution and apparent digestibility in restrictively fed heifers. Four grass-clover silages (Lolium perenne, Trifolium pratense and Trifolium repens) were harvested in 2009 at different regrowth stages, resulting in silages with NDF contents of 312, 360, 371 and 446 g/kg dry matter (DM), respectively. Four rumen-fistulated Jersey heifers (343 ± 32 kg BW) were fed silage at 90% of ad libitum levels in a 4 × 4 Latin square design, replicated with further restricted feeding levels (50%, 60%, 70% or 80% of ad libitum) in a balanced 4 × 4 × 4 Greco-Latin square design. Eating activity was estimated from test meal observations, while rumination activity was estimated from jaw movements logged by a jaw recorder system. Total tract digestibility was estimated from chromic oxide marker and fecal spot sampling, and fecal particle size distribution in washed and freeze-dried particulate DM was determined by dry sieving (2.36, 1.0, 0.5, 0.212 and 0.106 mm, and bottom bowl). Higher NDF content of silage stimulated longer eating time per kg DM intake (Psilages of decreasing NDF content increased chewing time relative to NDF intake, reduced mean fecal particle size, and increased DNDF digestibility. Restricting feeding level made heifers eat for a shorter time period while rumination and total chewing was increased, causing the ratio between eating and rumination time to decrease with lower intake of forage fiber. Particle size reduction and digestibility depended mostly on changes in NDF content, especially the indigestible NDF content.

  1. Phytogenic additive on the diet of dairy heifers: Hematological parameters Parâmetros hematológicos de novilhas leiteiras submetidas a dietas com aditivos fitogênicos

    Directory of Open Access Journals (Sweden)

    Fernando Reimann Skonieski

    2009-12-01

    Full Text Available With objective to evaluate the effects of utilization of herbal extracts on supplementation of dairy heifers was conducted an experiment utilizing 12 Jersey’s heifers, with mean age and weight at start of trial of eight months old and 112 kg, respectively. The animals were separated in two groups, with same number of replications, considered a Control group (without addition of herbal extracts and a Treatment group (with inclusion of 500 grams of herbal extracts per ton. of ration. The herbal extracts utilized were a mixture of garlic, onion, cinnamon, clove and linseed. The animals received, daily, divided in two feeding, 2 kg. of ration and, approximately, 3 kg. of alfalfa hay and 10 kg. of chopped fresh black oat and ryegrass. The hematological parameters evaluated were red blood cell count (106 units/ L, hemoglobin and plasmatic protein (g/ dL, hematocrit (%, leukocytes, lymphocytes, neutrophils, and monocytes (units/ L. There were observed significantly differences to red blood cell count and monocytes count (P < 0.10, lymphocytes count (P < 0.05 and leukocytes count (P < 0.01. It is concluded what herbal extracts act above hematological parameters of dairy heifers receiving this supplement.Com o objetivo de avaliar os efeitos da utilização de extratos vegetais na suplementação de novilhas leiteiras, foi conduzido um experimento com 12 novilhas Jersey, com idade e peso médio de 8 meses e 112kg, respectivamente. Os animais foram separados em dois grupos, com o mesmo número de repetições, um chamado grupo-controle (sem a adição de extratos vegetais e um grupo-tratamento (com a inclusão de 500 gramas de extratos vegetais por tonelada de ração. Os extratos vegetais utilizados foram uma mistura comercial de alho, cebola, canela, cravo e linhaça. Os animais receberam, diariamente, divididos em duas refeições, 2kg de ração, 3kg de feno de alfafa e 10kg de aveia e azevém fresco. Os parâmetros hematológicos avaliados foram hem

  2. Effects of feeding level and NDF content of grass-clover silages on chewing activity, fecal particle size and NDF digestibility in dairy heifers

    DEFF Research Database (Denmark)

    Schulze, A K S; Weisbjerg, M R; Nørgaard, P.

    2014-01-01

    The objective of this study was to assess effects of feed intake and NDF content of highly digestible grass-clover silage on chewing behavior, fecal particle size distribution and apparent digestibility in restrictively fed heifers. Four grass-clover silages (Lolium perenne, Trifolium pratense......, replicated with further restricted feeding levels (50%, 60%, 70% or 80% of ad libitum) in a balanced 4 × 4 × 4 Greco-Latin square design. Eating activity was estimated from test meal observations, while rumination activity was estimated from jaw movements logged by a jaw recorder system. Total tract...... digestibility was estimated from chromic oxide marker and fecal spot sampling, and fecal particle size distribution in washed and freeze-dried particulate DM was determined by dry sieving (2.36, 1.0, 0.5, 0.212 and 0.106 mm, and bottom bowl). Higher NDF content of silage stimulated longer eating time per kg DM...

  3. Genetic covariance functioners for live weight, condition score, and dry-matter intake measured at different lactations stages of Holstein-Friesian heifers

    NARCIS (Netherlands)

    Koenen, E.P.C.; Veerkamp, R.F.

    1998-01-01

    Genetic parameters for live weight, body condition score and dry-matter intake of dairy heifers were estimated using covariance function methodology. Data were from 469 heifers of the Langhill Dairy Cattle Research Centre and included observations during the first 25 weeks in lactation. Genetic

  4. Bagaço de mandioca em dietas de novilhas leiteiras: consumo de nutrientes e desempenho produtivo Cassava bagasse in diets of dairy heifers: intake of nutrients and productive performance

    Directory of Open Access Journals (Sweden)

    A.M. Dias

    2008-08-01

    Full Text Available A inclusão de quatro níveis, 0, 7, 14 e 21%, de bagaço de mandioca na dieta de novilhas leiteiras foi avaliada durante 56 dias. Utilizaram-se 20 novilhas leiteiras ¾Gir x ¼Holandês. Os animais foram distribuídos em quatro tratamentos e cinco repetições, recebendo dietas compostas por silagem de sorgo e concentrado, duas vezes ao dia. As dietas foram balanceadas para promover ganho de peso de 0,70kg/dia. Realizaram-se pesagens, a cada 28 dias, para determinar o ganho de peso. Avaliaram-se o consumo dos nutrientes, o ganho médio diário (GMD e a conversão alimentar (CA. O consumo foi expresso em kg/dia, porcentagem do peso corporal (%PC e gramas por kg de peso metabólico (g/kg0,75. Os consumos de matéria seca e de proteína bruta não foram influenciados pelos tratamentos, mas os consumos de fibra em detergente neutro e de fibra em detergente ácido apresentaram comportamento linear decrescente com o aumento do nível de bagaço; para o consumo de carboidratos não fibrosos, houve aumento linear (PThe inclusion of 0, 7, 14, and 21% of cassava bagasse in the diet of dairy was evaluated during 56 days. Twenty ¾Gir x ¼Holstein heifers were used, being five animals per treatment. The diets were balanced to provide a weight gain of 0.70kg/day, and it was measured at every 28 days. Intake of nutrients, average daily weight gain (DWG, and feed conversion (FC were evaluated. The intake was expressed in kg/day, body weight percentage (BW% and grams for kg of metabolic weight (g/kg0.75. The intakes of dry matter and crude protein were not affected by the inclusion of cassava bagasse to the diet, but intakes of the neutral detergent fiber and acid detergent fiber linearly decreased with the increase of the cassava bagasse level. However, the intake of non-fiber carbohydrates linearly increased (P<0.10. The DWG was 0.84; 0.80; 0.79; and 0.51 kg/day and the FC was 7.2; 7.5; 8.4; and 12.6 for treatments 0, 7, 14, and 21%, respectively. The best

  5. Use of dicarboxylic acids and polyphenols to attenuate reticular pH drop and acute phase response in dairy heifers fed a high grain diet.

    Science.gov (United States)

    De Nardi, Roberta; Marchesini, Giorgio; Plaizier, Jan C; Li, Shucong; Khafipour, Ehsan; Ricci, Rebecca; Andrighetto, Igino; Segato, Severino

    2014-11-26

    The aim of this study was to determine the ability of two feed additives, a fumarate-malate (FM) and a polyphenol-essential oil mixture (PM), in attenuating the drop of ruminal pH and the metabolic and immune response resulting from an excessively high grain diet. Six heifers were used in a 3 × 3 Latin square experiment and fed a low starch (LS) diet for 14 d, followed by a high starch (HS) diet for 8 d (NDF 33.6%, starch 30.0% DM). In the last 5 days of each period, barley meal was added to decrease rumen pH. During HS feeding all animals were randomly assigned to one of the following three dietary treatments: no supplement/control (CT), a daily dose of 60 g/d of FM, or 100 g/d of PM. Reticular pH was continuously recorded using wireless boluses. On d 21 of each period, rumen fluid was collected by rumenocentesis (1400 h), together with blood (0800 h) and fecal samples (0800, 1400, and 2100 h). The correlation coefficient of pH values obtained using the boluses and rumenocentesis was 0.83. Compared with CT and PM, the FM treatment led to a lower DMI. Nadir pH was lowest during CT (5.40, 5.69, and 5.62 for CT, FM and PM, respectively), confirming the effectiveness of both supplements in reducing the pH drop caused by high grain feeding. This result was confirmed by the highest average time spent daily below 5.6 pH (199, 16 and 18 min/d) and by the highest acetate to propionate ratio of the CT fed heifers. The PM decreased the concentrations of neutrophils (2.9, 3.2, and 2.8 10(9)/L) and acute phase proteins: SAA (37.1, 28.6 and 20.1 μg/mL), LBP (4.1, 3.8, and 2.9 μg/mL), and Hp (675, 695 and 601 μg/mL). Free lipopolysaccharides (LPS) were detected in blood and feces, but their concentrations were not affected by treatments, as the remaining blood variables. Data suggest that both additives could be useful in attenuating the effects of excessive grain feeding on rumen pH, but the PM supplement was more effective than FM in reducing the inflammatory response

  6. Estimation of fecal production, digesta flow and digestibility in dairy heifers with different indicator - doi: 10.4025/actascianimsci.v35i2.17338

    Directory of Open Access Journals (Sweden)

    Marcos Vinicius Biehl

    2013-03-01

    Full Text Available This study evaluated fecal excretion by means of the internal indicator indigestible neutral detergent fiber (iNDF and external indicators such as chromium complexed with ethylenediaminetetraacetic acid (Cr-EDTA and ytterbium chloride (YbCl3, in addition to estimating the duodenal flow of dry matter and the total, ruminal and post-ruminal apparent digestibility coefficients. Eight crossbred Holstein x Zebu heifers were distributed into a 4 x 4 Latin square. Indicators Cr-EDTA, YbCl3 and iNDF did not efficiently estimate the fecal production (p -1, respectively, compared with the total feces collection, which resulted in 1.39 kg day-1. The estimated values of dry matter flow, both for the methodologies of single and double indicator, can be considered biologically acceptable. However, the value obtained by the Cr-EDTA/YbCl3 association, used as a double indicator, was the most reliable, due to better recovery of the external indicators (Cr-EDTA and YbCl3, which have had averages of 89 and 85%, respectively, in comparison with the internal one (iNDF, which averaged 67%. The ruminal and post-ruminal digestibility coefficients, estimated by the Cr-EDTA/YbCl3 association, were considered the best indicators owing the dry matter flow estimated by this association.  

  7. Actividad sanguínea de superóxido dismutasa y glutatión peroxidasa en novillas a pastoreo Blood activity of superoxide dismutase and glutathione peroxidase in grazing dairy heifers

    Directory of Open Access Journals (Sweden)

    Santiago Jaramillo

    2005-11-01

    Full Text Available El objetivo de este estudio fue determinar el balance metabólico nutricional de Cu, Zn, Fe, Mn y Se, mediante la actividad sanguínea de SOD y GSH-Px y establecer la relación entre la concentración de Cu, Fe, Mn y Zn en el forraje y la actividad de SOD. Se tomaron 10 mL de sangre a 105 novillas seleccionadas en 15 rebaños lecheros de Caldas, Colombia (5º4' N y 75º3' O y se tomaron muestras de forrajes para analizar Cu, Fe, Mn y Zn. El promedio de la actividad de SOD fue 1.390±1.299 U g-1 Hb, y estaba correlacionada con Cu, Mn y Fe en el forraje. La actividad promedio de GSH-Px fue 389±184 U g-1 Hb y fue observada una mayor frecuencia de valores deficitarios y bajo/marginales de 9%, habiendo sido más afectados los animales de zonas altas (>2.000 msnm. Bajo estas condiciones, estos resultados permiten señalar que la SOD es una enzima que puede emplearse como indicador del balance metabólico nutricional de Cu, Mn y Fe en bovinos a pastoreo, no está clara todavía su relación con Zn. La actividad de GSH-Px indica deficiencias en el balance metabólico nutricional de Se, en bovinos a pastoreo.The objective of this study dealt with the evaluation of the metabolic nutritional status of Cu, Zn, Mn, Fe and Se in grazing dairy heifers, through the determination of the activity of SOD and GSH-Px in blood. Blood samples (10 mL were taken from 105 heifers randomly selected in 15 dairy farms in Caldas, Colombia (5º4' N y 75º3' W. Forage samples were also collected to analyze Cu, Fe, Mn, and Zn. Mean activity of SOD was 1,390±1,299 U g-1 Hb, and it was related to the content of Cu, Mn, and Fe in the forage. Mean blood activity of GSH-Px was 389±184 U g-1 Hb. The highest frequency of values under the reference was about 9%; animals located over 2,000 m over sea level were the most affected. SOD is useful to determine the nutritional metabolic status of Cu, Mn and Fe, but the relationship with Zn is not clear yet, and requires further

  8. Perfil metabólico e desenvolvimento da glândula mamária de novilhas leiteiras sob manejo para crescimento compensatório Metabolic profile and mammary gland development of dairy heifers under compensatory growth regime

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    Patrícia Barcellos Costa

    2012-02-01

    Full Text Available Objetivou-se avaliar o efeito do manejo para crescimento compensatório e da suplementação com ionóforo sobre o perfil metabólico e o crescimento da glândula mamária de novilhas leiteiras. Foram utilizadas 20 novilhas Pardo-Suíças puras, com peso inicial de 200 kg e 5 meses de idade. Os tratamentos foram arranjados em esquema fatorial 2 × 2 e os animais foram alocados aleatoriamente em cada uma das combinações. O fator 1 consistiu dos sistemas de alimentação (convencional e crescimento compensatório e o fator 2, da utilização ou não de ionóforo (200 mg de monensina/animal/dia. Os animais do sistema convencional receberam alimentação ad libitum, enquanto os do sistema para crescimento compensatório foram submetidos a um manejo nutricional com dois períodos distintos: período de restrição energética (90 dias, P1 e período de realimentação (60 dias, P2. Novilhas submetidas ao sistema crescimento compensatório apresentaram maior concentração de nitrogênio ureico (N-ureico plasmático e menor razão DNA:RNA no tecido mamário. Quando analisados dentro de período, os níveis de lipoproteínas de alta densidade (HDL aumentaram no período de realimentação, enquanto os de N-ureico diminuíram. Além da alteração nos níveis de N-ureico, o balanço energético ao qual as novilhas em crescimento compensatório foram submetidas ocasionou aumento no teor dos ácidos graxos não-esterificados. Houve redução nos níveis de glicose sanguínea dos animais em crescimento compensatório no período de realimentação. A suplementação com ionóforo proporciona menor concentração de ácidos graxos não-esterificados durante o período de realimentação.The objective of this trial was to compare the effect of compensatory growth regime on the metabolic profile and mammary gland development of dairy heifers. Twenty Brown-Swiss heifers averaging 200 kg of body weight and five months of age were used in a completely

  9. Nutritionally directed compensatory growth enhances heifer development and lactation potential.

    Science.gov (United States)

    Ford, J A; Park, C S

    2001-07-01

    The objectives of this study were 1) to examine the interactive influence of a compensatory nutrition regimen and lasalocid supplementation on dairy heifer growth performance and 2) to document the extent to which compensatory growth sustains lactation potential over the first two lactation cycles. Twelve Holstein heifers, weighing an average of 160 kg (about 6 mo of age) were randomly assigned to treatments arranged in a 2 x 2 factorial design. Treatment variables were two dietary regimens (control and stair-step compensatory nutrition) and two levels of lasalocid (0 and 200 mg/d). The control heifers were fed a diet containing 12% crude protein (CP) and 2.35 Mcal of metabolizable energy (ME) per kilogram of dry matter. The stair-step compensatory nutrition heifers were subjected to a phased nutrition regimen and reared according to an alternating 3-2-4-3-4-2-mo schedule. The first stair-step (prepubertal phase) consisted of energy restriction [17% CP and 2.35 Mcal/kg of ME] for 3 mo followed by realimentation (12% CP and 3.05 Mcal/kg of ME) for 2 mo. The second step (puberty and breeding) consisted of energy restriction for 4 mo followed by realimentation for 3 mo. The third step (gestation period) was energy restriction for 4 mo concluding with realimentation for 2 mo. Dry matter intake of heifers during the restriction phase was limited to 70% of the control intake. Heifers were given ad libitum access to a high energy density diet during realimentation to allow compensatory development. Stair-step heifers supplemented with lasalocid had the highest efficiency of growth (body weight gain/dry matter intake), suggesting synergistic metabolism of lasalocid with compensatory growth action. Compensatory growth induced during the last trimester enhanced metabolic status by increasing circulating insulin and decreasing triglyceride levels. Heifers on the stair-step regimen had a significant increase in milk yield during the first (21%) and second (15%) lactation

  10. Growth performance and total tract nutrient digestion for Holstein heifers limit-fed diets high in distillers grains with different forage particle size

    Science.gov (United States)

    This study evaluated dairy heifer growth performance and total tract nutrient digestion when fed diets high in dried distillers grains with solubles (DDGS) with different forage particle size. An 8-wk randomized complete block design study was conducted utilizing twenty-two Holstein heifers (123 ±...

  11. Argentine tango in Parkinson disease.

    Science.gov (United States)

    2016-10-28

    This article reports on a meta-analysis of 13 studies of the effects of Argentine tango (AT) as a music-based movement therapy for people with Parkinson's disease (PD). Nine studies involved randomised controlled trials.

  12. Nonpuberal estrus in beef heifers.

    Science.gov (United States)

    Rutter, L M; Randel, R D

    1986-10-01

    The frequency of occurrence of behavioral estrus without subsequent development of functional luteal tissue (termed nonpuberal estrus, NPE), was determined in 43 Simmental X Hereford-Brahman heifers. Blood samples were collected weekly from the start of the study to first behavioral estrus and then daily from d 1 (d 0 = estrus) through d 14 following first and subsequently observed estrous behaviors. All blood samples were analyzed for serum progesterone (P4) concentrations by radioimmunoassay. More heifers (62.8%) exhibited NPE than had luteal development after their first behavioral estrus (37.2%). There was a tendency for fewer light-weight heifers (less than or equal to 240 kg at the start of the experiment) to exhibit a puberal first estrus compared with the heavy-weight (greater than 240 kg at the start of the experiment) heifers (31.2% vs 68.8%, respectively; P = .12). Heifers that had a puberal first estrus were older (376 +/- 12 d vs 334 +/- 9 d, P less than .05) compared with heifers that had NPE. Weight at first behavioral estrus was similar between heifers that had a puberal first estrus and those that had NPE (298 +/- 8 kg and 289 +/- 6 kg, respectively). More heifers that had a puberal first estrus also had an elevation in serum P4 concentrations before that first estrus (64.3% vs 20.0%, P less than .05), and the serum P4 elevation was greater (2.5 +/- .4 ng vs 1.2 +/- .1 ng, P less than .05) than heifers that had NPE. We have concluded from these results that NPE is a common occurrence in heifers approaching puberty.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Evaluation of the California Mastitis Test as a precalving treatment selection tool for Holstein heifers.

    Science.gov (United States)

    Roy, Jean-Philippe; Du Tremblay, Denis; Descôteaux, Luc; Messier, Serge; Scholl, Daniel; Bouchard, Emile

    2009-02-16

    The objective of this study was to evaluate the California Mastitis Test (CMT) and a portable electrical conductivity meter for diagnosing precalving intramammary infection (IMI) in Holstein heifers. A total of 428 dairy heifers from 23 dairy herds were enrolled between 6 and 12 days before the expected calving date from June 2002 to June 2003. Mammary secretions were tested by both diagnostic methods and by bacterial culture for evidence of IMI. California Mastitis Test was considered negative if the score was negative, trace or 1 and was considered positive otherwise. Two cut-off points were evaluated for milk electrical conductivity (>5 and >6.5 mS/cm). From this study, an overall proportion of 69% of heifers had precalving IMI and the overall heifer prevalence of major pathogen IMI was 16.8%. At the quarter level, sensitivity and specificity of CMT (68.9% and 68.4%, respectively) and milk conductivity >5 mS/cm (41.0% and 65.2%, respectively) or >6.5 mS/cm (25.2% and 83.3%, respectively) to identify all IMI were low. However, the heifer level sensitivity and specificity of CMT for major pathogens were 91.0% (81.5-96.6) and 27.5% (22.8-32.6), respectively. Using a cut-off point of 5 mS/cm, the heifer level sensitivity and specificity for major pathogens was 68.7% (56.2-79.4) and 44.1% (38.7-49.6), respectively. A conductivity cut-off value of 6.5 mS/cm decreased the sensitivity and increased the specificity to 53.7% (41.1-66.0) and 59.5% (54.0-64.8), respectively. California Mastitis Test and milk electrical conductivity are not good predictors of major pathogen IMI in heifers during the last 2 weeks before calving. However, the negative predictive values at quarter or heifer level were high and the heifer false negative rate was 6-14% using CMT or conductivity, respectively. Therefore, these measures could be useful for screening out heifers or quarters that are unlikely to have a major pathogen IMI.

  14. Consumo, digestibilidade, desempenho, desenvolvimento ponderal e economicidade de dietas com polpa cítrica em substituição ao feno de capim-tifton 85 para novilhas leiteiras Effects of partial replacement of Tifton 85 hay with citrus pulp on intake, performance, and development of dairy heifers

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    Josué Mendes Neto

    2007-06-01

    Full Text Available Objetivou-se determinar o consumo, a digestibilidade, o desempenho, o desenvolvimento ponderal, a conversão alimentar e a economicidade de dietas com polpa cítrica em substituição ao feno de tifton 85 (Cynodon dactylon (L. Pear para novilhas leiteiras. Os tratamentos consistiram de quatro níveis (0; 16,6; 33,3 e 50% de substituição do feno por polpa cítrica. Os dados foram analisados em delineamento experimental de blocos casualizados com sete repetições. Utilizaram-se 28 novilhas holandesas (12 meses de idade e peso médio inicial de 184 kg mantidas em baias individuais. Os consumos de MS, MO, PB, CT e NDT aumentaram linearmente e o de FDN decresceu à medida que o feno foi substituído pela polpa cítrica. O consumo de EE elevou de forma quadrática com aumento dessa substituição, apresentando valor mínimo quando 2,27% do feno foi substituído pela polpa cítrica. Os consumos de Ca e P aumentaram com o aumento dos níveis de substituição do feno. Os coeficientes de digestibilidade aparente da MS, MO, PB e FDN reduziram linearmente, enquanto os de EE e CT não foram influenciados pela substituição. O ganho de peso aumentou linearmente, mas o crescimento de altura de cernelha foi menor e o de altura de garupa não foi influenciado pelos níveis de substituição. Observou-se aumento linear no perímetro torácico à medida que o feno foi substituído pela polpa cítrica. A polpa cítrica pode ser utilizada em até 35% da dieta total na alimentação de novilhas leiteiras de acordo com a conveniência econômica e a disponibilidade de alimentos volumosos, como alternativa para o produtor reduzir a idade à primeira cobertura e ao primeiro parto, com menor custo de alimentação.The objective of this trial was to evaluate intake, digestibility, performance, development, feed efficiency and feeding costs in dairy heifers fed increasing levels of citrus pulp that partially replaced Tifton-85 hay (Cynodon dactylon (L. Pear in the

  15. Contemporary Argentine Cinema during Neoliberalism

    Science.gov (United States)

    Rocha, Carolina

    2009-01-01

    In this article I analyze contemporary Argentine cinematic production assessing the impact of Law 24,377 that was implemented in 1995 and that provided much-needed funds for national productions. By looking at film production and consumption, the emergence of young filmmakers and the performance of both commercial films and those belonging to the…

  16. Carlos Mayo and Argentine historiography

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    Sara E. Mata

    2012-11-01

    Full Text Available The work of Carlos Mayo is distinguished by its originality and academic excellence. Our goal has been to briefly address their valuable contributions to the Argentine historiography, particularly that relating to the agricultural history of the Río de la Plata

  17. Contemporary Argentine Cinema during Neoliberalism

    Science.gov (United States)

    Rocha, Carolina

    2009-01-01

    In this article I analyze contemporary Argentine cinematic production assessing the impact of Law 24,377 that was implemented in 1995 and that provided much-needed funds for national productions. By looking at film production and consumption, the emergence of young filmmakers and the performance of both commercial films and those belonging to the…

  18. Desempenho e desenvolvimento ponderal de novilhas leiteiras alimentadas com dietas à base de cana de açúcar Performance and ponderal development of dairy heifers fed sugar cane based diets

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    Lídia Ferreira Miranda

    1999-01-01

    Full Text Available O objetivo deste trabalho foi avaliar o desempenho e o desenvolvimento ponderal de novilhas alimentadas com dietas à base de cana-de-açúcar suplementadas com fontes de nitrogênio não-protéico (NNP (uréia ou cama de frango, em substituição parcial da uréia e, ou, adição de probióticos (sem probiótico, levedura ou microbiota ruminal. O custo e a margem bruta do uso destas dietas também foram analisados. Vinte e quatro novilhas, com idade e peso médio inicial de 15 meses e 247 kg PV, respectivamente, foram mantidas em baias individuais e alimentadas durante o período experimental de 84 dias. Os animais foram distribuídos em delineamento inteiramente casualisado, em esquema fatorial 2 x 3 (fonte de NNP vs fonte de probiótico, com quatro repetições. As novilhas foram pesadas e o perímetro torácico e a altura de cernelha e garupa foram determinados no início e no final do período experimental e a cada 28 dias. Os níveis de N-uréia plasmáticos das novilhas foram determinados em amostras de sangue coletadas imediatamente antes do fornecimento diário de alimento, zero hora, e às duas, quatro, seis e oito horas após a alimentação. Não houve interação entre fontes de nitrogênio e fontes de probióticos, para qualquer característica estudada. A suplementação da cana-de-açúcar com fontes NNP não apresentou diferença no ganho de peso diário dos animais. Entretanto, a adição de levedura ou microbiota ruminal promoveu ganhos semelhantes, porém superiores à sem adição de probióticos. A substituição parcial da uréia pela cama de frango não influenciou o desempenho das novilhas, mas as dietas suplementadas com levedura ou microbiota ruminal apresentaram maiores ganho de peso e desenvolvimento ponderal.The objective of this work was to evaluate the performance, ponderal development of heifers fed sugar cane based diets, supplemented with non protein nitrogen (NPN sources (urea or broiler litter, in replacement

  19. Balanço de compostos nitrogenados e produção de proteína microbiana em novilhas leiteiras alimentadas com casca de café em substituição à silagem de milho Nitrogen compounds balance and microbial protein production in dairy heifers fed with coffee husk in substitution of corn silage

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    Rafael Monteiro Araújo Teixeira

    2007-10-01

    Full Text Available Objetivou-se avaliar o efeito da substituição da silagem de milho pela casca de café em dietas para novilhas leiteiras sobre as variáveis ruminais, o balanço de compostos nitrogenados e a produção de proteína microbiana. Foram utilizadas 24 novilhas leiteiras da raça Holandesa, puras e mestiças, distribuídas em um delineamento em blocos casualizados, com quatro tratamentos e seis blocos, formados de acordo com o peso inicial dos animais. Os tratamentos experimentais foram constituídos de quatro níveis de casca de café: 0,0; 7,0; 14,0 e 21,0 (% MS total em substituição à silagem de milho. Diariamente, todas as novilhas foram alimentadas com 2 kg de concentrado. O consumo de compostos nitrogenados (N e a excreção de N fecal e urinário aumentaram linearmente com a substituição da silagem de milho pela casca de café, o que resultou em balanço de N positivo, com média de 22,31 g/dia para todas as dietas, porém, a porcentagem de N absorvido em relação ao consumido reduziu linearmente. A concentração de amônia ruminal e a concentração de uréia no plasma (NUS, média de 11,03 e 10,08 mg/dL, respectivamente, não foram afetadas pela inclusão da casca de café na dieta. As excreções de ácido úrico, alantoína e de derivados de purina, as purinas absorvidas, o N microbiano (Nmic e a eficiência microbiana (Efic M reduziram linearmente com a substituição parcial da silagem de milho pela casca de café, com redução de 1,08 g/dia of Nmic e de 1,96 gPB/kg NDT de Efic M por unidade de casca de café adicionada à dieta. A inclusão de casca de café em níveis de até 21% MS em dietas para novilhas leiteiras reduz a produção de nitrogênio microbiano e a eficiência microbiana, o que pode prejudicar o desempenho animal.The objective was to evaluate the effect of the substitution of corn silage by coffee husk in diets for dairy heifers on the ruminal variables, nitrogenous compounds and e microbial protein production

  20. Evaluación productiva de hembras en desarrollo de genotipos lecheros en unaasociación de gramíneas con leucaena Productive evaluation of growing heifers from dairy genotypes in an association of grasses with leucaena

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    O López

    2010-06-01

    Full Text Available Con el objetivo de evaluar las ganancias de peso en toros que consumían hollejo de cítrico fresco o conservado, se realizó un estudio durante 120 días en dos cebaderos de la Empresa Citrícola «Victoria de Girón», en Jagüey Grande, Matanzas. Ambas unidades disponían de 400 animales y la raza predominante era Cebú comercial. El manejo consistió en pastoreo restringido (cuatro horas y estabulación (20 horas. La disponibilidad de pasto fue de 5 y 3 kg de MS/animal/día para la lluvia y la seca, respectivamente. Las dietas consistieron en forraje verde y hollejo de cítrico fresco o ensilado a voluntad. Además se suplementó con 0,5; 1,0; 1,1 y 0,05 kg/animal/día de heno, residuos fermentados de maíz, afrecho de trigo y sal mineral, respectivamente; la urea se ofreció según los balances alimentarios. Se midió el consumo de los alimentos voluminosos y la ganancia de peso vivo. Se efectuaron balances alimentarios previos y retrospectivos al finalizar el estudio. La mayor ingestión de forraje (8,1 vs 7,7 kg/animal/día se obtuvo en la dieta de hollejo fresco. Las ganancias fueron de 0,641 vs 0,633 kg/animal/día para los animales que consumían hollejo fresco y ensilaje, respectivamente. La conversión alimentaria fue alta (11,4 y 11,6 para los animales que disponían de hollejo fresco y ensilado, respectivamente. Esta evaluación demostró que en igualdad de condiciones, no hubo grandes diferencias productivas al emplear cualquiera de las dos formas de suministro.In order to evaluate the productive performance of growing heifers, in systems with association of grasses and leucaena, 15 F1 (Holstein x Zebu and 15 creole crossbred heifers were studied in unit 2 of the UBPC «Ramón Paz», belonging to the Livestock Production Firm Martí, Matanzas. The work was conducted between July, 2005 and June, 2006; the stocking rate was 1,3 animals/ha. The main measurements were: floristic composition of the pastureland, pasture and leucaena

  1. Transformations in the Argentine dairy sector. The "mediería"as work social form Transformaciones en el Complejo Lácteo Argentino. La mediería como forma social de trabajo

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    Florencia Beltrame

    2010-01-01

    Full Text Available The transformations of the dairy sector and rural social structure in Argentina have been taking place along the last decades. This process meant a profound restructuring of the pampas region. Throughout this work, we will see how the processes of technological change and restructuring resulted in a transformation of the "mediería" as a social and labor relation. It means, the relations of "mediería" had transformed according to the new requirements of the dairy production clusters. In summary, in this work we will discuss the transformations of the labor organization in the dairy sector in Argentina as a result of the modernization processes.El complejo lácteo argentino y la estructura social rural en su conjunto, han experimentando importantes transformaciones en las últimas décadas, llevando a una profunda reestructuración del agro pampeano. A lo largo del presente trabajo, veremos cómo los procesos de cambio tecnológico y reestructuración de la actividad, tuvieron como consecuencia no el reemplazo o desplazamiento, sino más bien la transformación de la figura de la mediería como forma social del trabajo. Ésta última, debió transformarse de acuerdo a los nuevos requerimientos del sistema alimentario. De esta forma, analizaremos la forma que adquirió la organización del trabajo en el complejo lácteo como consecuencia de los procesos de modernización.

  2. Influence of prepartum pirlimycin hydrochloride or penicillin-novobiocin therapy on mastitis in heifers during early lactation.

    Science.gov (United States)

    Oliver, S P; Gillespie, B E; Ivey, S J; Lewis, M J; Johnson, D L; Lamar, K C; Moorehead, H; Dowlen, H H; Chester, S T; Hallberg, J W

    2004-06-01

    A study was conducted in 2 dairy research herds to determine whether prepartum therapy of heifer mammary glands with penicillin-novobiocin or pirlimycin hydrochloride was effective for reducing the percentage of heifers and mammary quarters infected with mastitis pathogens during early lactation. Almost 96% of Jersey heifers (67 of 70) and 71.3% of quarters (199 of 279) were infected 14 d before expected calving. Of the quarters infected at 14 d before expected parturition, 75% (54 of 72) were uninfected following treatment with penicillin-novobiocin; 87% (61 of 70) were uninfected following treatment with pirlimycin, and 56% (32 of 57) were uninfected in the untreated negative control group. The majority of intramammary infections in Jersey heifers were due to coagulase-negative staphylococci (61%), Streptococcus species, primarily Streptococcus uberis (19%), and Staphylococcus aureus (8%). Almost 73% of Holstein heifers (40 of 55) and 34.3% of mammary quarters (73 of 213) were infected 14 d before expected calving. Of the quarters infected at 14 d before expected parturition, 76% (19 of 25) were uninfected following treatment with penicillin-novobiocin; 59% (17 of 29) were uninfected following treatment with pirlimycin, and 26% (5 of 19) were uninfected in the untreated negative control group. The majority of intramammary infections in Holstein heifers were due to coagulase-negative staphylococci (44%) and Staph. aureus (30%). In both herds, the bacteriological cure rate was significantly higher in heifer mammary glands treated with penicillin-novobiocin or pirlimycin hydrochloride than in untreated controls. Prepartum therapy of heifer mammary glands with penicillin-novobiocin or pirlimycin hydrochloride significantly reduced the percentage of heifers and quarters infected with mastitis pathogens during early lactation.

  3. Immune Responses of Dairy Cattle to Parainfluenza-3 Virus in Intranasal Infectious Bovine Rhinotracheitis-Parainfluenza-3 Virus Vaccines

    OpenAIRE

    Burroughs, A.L.; Morrill, J L; Bostwick, J.L.; Ridley, R K; Fryer, H. C.

    1982-01-01

    Two hundred and fifty dairy heifers were vaccinated at three to six months of age with an intranasal infectious bovine rhinotracheitis-parainfluenza-3 vaccine. Eighteen additional heifers were tested prior to vaccination and again three to four weeks after vaccination. Neither cell-mediated nor humoral immunity was significantly raised to parainfluenza-3 virus in either group of cattle.

  4. Molecular Typing of Mastitis-Causing Staphylococcus aureus Isolated from Heifers and Cows

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    Juliana Rodrigues Pozzi Arcaro

    2013-02-01

    Full Text Available Staphylococcus aureus is among the main etiologic agents of bovine mastitis. A total of 83 isolates of S. aureus from mammary glands of primiparous heifers were collected in the prepartum, calving and during lactation. For lactating cows, a total of 27 isolates of S. aureus from mammary glands were collected during lactation. The samples were taken in two dairy farms located in Sao Paulo State, Brazil. The highest frequency of S. aureus isolation in heifers was at the end of lactation. Strains were typified through Pulsed-field gel electrophoresis (PFGE and grouped according to patterns of restriction enzyme SmaI. PFGE generated seven clonal profiles that were grouped into three different lineages, with the LA lineage being predominant and identified in heifers, as well as in the cows from the two regions studied. It was concluded that the cows showed a significant source of dispersion of S. aureus. At the first lactation the heifers were infected by the same clonal profiles of S. aureus which were isolated from multiparous lactating cows. The heifers were infected during milking over the months of lactation.

  5. REDUCING THE AGE AT FIRST CALVING THROUGH NUTRITIONAL MANIPULATIONS IN DAIRY BUFFALOES AND COWS: A REVIEW

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    S. A. BHATTI, M. SARWAR, M. S. KHAN1 AND S. M. I. HUSSAIN

    2007-01-01

    Full Text Available Raising heifers is the most expensive component of the dairy farm operations. Poor growth rate resulting in delayed age at maturity in our local dairy animals further aggravates the situation. However, cost of heifer production can be reduced through better management, balanced feeding, use of performance modifiers and better health care. Selection for higher milk yield is likely to have a favorable impact on age at first calving. Yet, the current age at maturity in buffalo and Sahiwal cow can be reduced to 2 and 1.5 years, respectively, with better feeding and management. Protein and energy are the most critical nutrients affecting the weight and consequently age at puberty in heifers. Higher protein levels than current recommendations of NRC for dairy cattle can reverse the adverse effects of high plane of nutrition on udder development. Accelerated growth rate through performance modifiers to reduce the age at maturity is also helpful provided they do not adversely affect development of secretory tissue of udder for future milk production. Judicious use of balanced feed and performance modifiers has led to reduced age at puberty in exotic dairy heifers. These data can be used to device optimum heifer production systems in the country. However, for offering solid recommendations on optimum heifer production requires well planned research to see the effects of proteins, energy, minerals and other performance modifiers for economical heifer production in our country.

  6. Suspected ergotism in two heifers.

    Science.gov (United States)

    Fraser, D M; Dorling, P R

    1983-10-01

    A syndrome similar to gangrenous ergotism was seen in 2 Friesian heifers grazing meadow hay containing perennial rye grass seed heads parasited by an ergot presumed to be Claviceps purpurea. Clinical signs were bilateral hind limb lameness and gangrene. There was angiographic evidence of vasoconstriction in the lower hind limbs with necrosis of all tissues in the distal region of both hind limbs.

  7. Cama de frango e suplemento à base de microbiota ruminal em dietas de novilhas leiteiras: desempenho produtivo e avaliação econômica Broiler litter and supplement based on ruminal microbiota in dairy heifers diets: performance and economic evaluation

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    José Carlos Pereira

    2003-06-01

    Full Text Available O trabalho foi conduzido para avaliar o desempenho de novilhas de rebanhos leiteiros recebendo dietas contendo cama-de-frango (CF e suplemento à base de microbiota ruminal (SMR. Foram utilizadas 20 novilhas mestiças Holandês-zebu, com peso médio inicial de 276 kg e idade média de 13,8 meses. Os animais foram distribuídos aleatoriamente em arranjo fatorial 2x2, no qual foram estudados dois níveis de CF (15 e 30% na matéria seca e de SMR (0 e 10 g/animal/dia, em delineamento inteiramente casualizado, com cinco repetições. Foram avaliados o consumo, o ganho de peso e a conversão alimentar e calculados os custos com alimentação, sendo composto um fluxo de caixa simulado para recria dos animais em confinamento e a pasto. Os consumos de matéria seca, matéria orgânica, proteína bruta e fibra em detergente neutro não foram influenciados pelos níveis de CF ou de SMR. O ganho de peso médio diário foi maior para as novilhas recebendo dietas com 15% de CF e 10 g de SMR (1,13 kg, em relação ao tratamento com 15% de CF sem SMR (0,85 kg. Entretanto, não houve diferenças em relação aos animais alimentados com 30% de CF com e sem SMR (1,09 e 0,97 kg. Não foram observadas diferenças para conversão alimentar da matéria seca e da fibra em detergente neutro, e houve interação entre os níveis de cama-de-frango e de suplemento para a conversão alimentar da proteína bruta. Melhor relação custo/benefício foi encontrada para o tratamento 30% de CF sem SMR, em relação ao nível de 15% sem SMR, porém não-significativa para os demais. O fluxo de caixa simulado mostrou que o sistema de recria de novilhas em confinamento foi economicamente mais vantajoso que o sistema em regime de pasto, para as condições do presente trabalho.This research was carried out to evaluate the performance of dairy heifers fed with broiler litter (BL and ruminal microbiota supplement (RMS. Twenty heifers, crossbred Holstein x zebu, with average weight and

  8. Parâmetros ruminal, sangüíneo e urinário e digestibilidade de nutrientes em novilhas leiteiras recebendo diferentes níveis de monensina Effects of different dietary levels of monensin on nutrient digestibility and on ruminal, blood and urinary metabolites in dairy heifers

    Directory of Open Access Journals (Sweden)

    Marcus Vinicius Morais de Oliveira

    2005-12-01

    Full Text Available Objetivou-se verificar a influência da inclusão de diferentes níveis do ionóforo monensina sódica na dieta sobre os parâmetros ruminal, sangüíneo e urinário e a digestibilidade aparente em novilhas leiteiras. Foram coletadas amostras de líquido ruminal (imediatamente antes e duas horas após a alimentação, sangue, urina e fezes de 28 novilhas da raça Holandesa mantidas em regime de confinamento por 84 dias. As dietas possuíam 32,84% de concentrado (grão de milho, farelo de soja, uréia e mistura mineral, 33,58% de silagem de milho e 33,58% de cana-de-açúcar na matéria seca. Os níveis de ionóforo avaliados foram 0, 14, 28 e 42 mg de monensina/kg de matéria seca da dieta. O experimento foi instalado conforme delineamento inteiramente casualizado, com quatro tratamentos e sete repetições, realizando-se estudos de regressão e contrastes ortogonais. Antes da alimentação, a monensina não influenciou o pH ruminal e a concentração de amônia e dos ácidos acético, propiônico e butírico, mas promoveu redução da relação acetato:propionato. Duas horas após a alimentação, verificou-se redução do pH e da relação acetato:propionato; e aumento da concentração de ácido propiônico. O estudo de contrastes revelou que ocorreu diminuição da concentração de amônia antes da alimentação. Não foram verificadas mudanças significativas nas concentrações de glicose e uréia sangüínea. A monensina também não influenciou os consumos de matéria seca (MS, matéria orgânica, proteína bruta, extrato etéreo (EE, carboidratos totais (CHOT e fibra em detergente neutro. As digestibilidades da MS, EE e CHOT e a perda de nitrogênio urinário apresentaram respostas quadráticas.The objective of this trial was to study the effects of different dietary levels of the ionophore monensin on apparent digestibility of nutrients and on ruminal, blood, and urinary metabolites in dairy heifers. Samples of ruminal fluid (pre

  9. Desempenho produtivo de fêmeas leiteiras alimentadas com silagem de milho e concentrado à base de farelo de soja ou farelo de algodão Productive performance of growing dairy heifers fed corn silage and soybean or cottonseed meal based concentrate

    Directory of Open Access Journals (Sweden)

    Stefanie Alvarenga Santos

    2010-03-01

    Full Text Available Foram avaliadas dietas com silagem de milho e concentrado à base de farelo de soja ou farelo de algodão para fêmeas leiteiras. Quatro dietas experimentais foram constituídas da combinação de dois níveis de concentrado (1 ou 2 kg e duas fontes proteicas (farelo de soja ou farelo de algodão. Observou-se efeito da interação nível de concentrado × fonte proteica no consumo de matéria seca (MS, fibra em detergente neutro (FDN e no consumo de nutrientes digestíveis totais (NDT. A quantidade de concentrado influenciou os consumos de proteína bruta (PB, FDN, extrato etéreo (EE, carboidratos nãofibrosos (CNF, matéria orgânica (MO e de PB por kg de NDT. Não houve efeito nas digestibilidades da MS, FDN, MO e para NDT, porém a fonte proteica influenciou as digestibilidades de PB, EE e CNF. Houve efeito da quantidade de concentrado sobre o ganho de peso (GP e da interação quantidade de concentrado × fonte proteica sobre o ganho de peso por cm de ganho em altura da cernelha. A dieta com 1 kg de concentrado à base de farelo de algodão foi insuficiente para ganho de peso de 800 g/dia, enquanto as dietas com 2 kg de concentrado propiciaram o maior ganho de peso. Entretanto, a dieta constituída de 2 kg de concentrado à base de farelo de soja foi mais eficiente, pois propiciou maior crescimento linear das novilhas, com ganho médio de 820 g por dia. Equações de predição do peso corporal com base no perímetro torácico apresentam maior acurácia em relação a equações baseadas em outras medidas lineares.Diets for dairy heifers were assessed with corn silage and soybean or cotton seed based concentrate. Four experimental diets consisting of the combination of two concentrate levels, 1 or 2 kg, and two protein sources, soybean meal or cotton seed meal. The effect of the interaction was observed for intake of dry matter (DM, neutral detergent fiber (NDF in % live weight and total digestible nutrient intake (TDN. The quantity of

  10. Can rapeseed lower methane emission from heifers?

    DEFF Research Database (Denmark)

    Hellwing, Anne Louise Frydendahl; Sørensen, Martin Tang; Weisbjerg, Martin Riis

    2013-01-01

    Twelve heifers were assigned to either a control diet (CON) with 26 g fat per kg dry matter (DM) or a supplemented diet (FAT) with crushed rapeseed with 53 g fat per kg DM. Methane (CH4) emission was measured by open-circuit indirect calorimetry for four days when the heifers weighed approximately...

  11. Enterprise level implications of heifer development

    Science.gov (United States)

    Research emphasis has been placed on heifer development strategies in recent years, comparing traditional, more intensive systems to more extensive systems using less feed and relying on compensatory gain to reach a target BW. Recent research has suggested that developing heifers to a lighter target...

  12. Artificial insemination field data on the use of sexed and conventional semen in nulliparous Holstein heifers.

    Science.gov (United States)

    Healy, A A; House, J K; Thomson, P C

    2013-03-01

    This study investigated conception rates and other reproductive outcomes achieved with artificial insemination (AI) of nulliparous Holstein heifers using sexed and conventional semen in a commercial Australian dairy herd in central western New South Wales from January 2004 to April 2009. Retrospective data from on-farm records of 9,870 inseminations of 4,456 heifers were analyzed using several mixed models to assess the effect of temperature and humidity surrounding breeding, insemination sire, artificial insemination technician, service number, and heifer weight and age at breeding on reproductive traits (conception rates, sex ratios, gestation length, and abortion and stillbirth rates). Semen was used from 15 sexed sires and 41 unsexed sires. Sexed semen was primarily used at first and second service. Empirical conception rates of 31.6 and 39.6% were achieved for sexed and unsexed semen respectively, whereas model-based predictions were lower, at 21.3 and 32.1%. Conception rates were significantly affected by insemination sire, sex-sorting, heifer age at breeding, temperature and humidity surrounding breeding, service number, and AI technician. Sexed semen yielded 86% heifers, compared with 48% for conventional semen. Significant predictors of calf sex included semen sexing, gestation length, and insemination sire. Twinning rate was high, at 3.6% for both semen types, and gestation length and heifer weight at breeding were significant predictors of twinning. Abortion rates for sexed and unsexed conceptions were similar at 6.1 and 6.5%, respectively, and were affected by heifer age at breeding. Stillbirth rate was affected by calf sex, twinning, gestation length, and AI technician; semen sorting, age at breeding, and temperature and humidity were marginally significant predictors. No abnormalities were observed in the development of offspring, except for a marginally higher stillbirth rate for sexed calves, a finding that needs further investigation. Many

  13. Risk Factors Influencing Conception Rate in Holstein Heifers before Artificial Insemination or Embryo Transfer

    Directory of Open Access Journals (Sweden)

    M. Yusuf

    2016-12-01

    Full Text Available The objective of this study was to show the risk factors affecting the conception rate in Holstein heifers after synchronization of estrus. A total of 275 Holstein heifers housed in a free barn were used for the experiment. The herd was visited regularly at four week intervals for synchronization of estrus using Heatsynch and CIDR-Heatsynch protocols. A group of four to 14 animals, depending on the availability, were referred to the experiment at each visit. Estrus induction rates in the two protocols were 93.9% and 94.9%, respectively. There was no difference in the conception rate between the two protocols. Conception rate after artificial insemination (AI or embryo transfer (ET were 46.3% and 51.4%, respectively. The risk factors affecting conception rate in heifers were daily weight gain (odds ratio [OR]= 4.673; P= 0.036 and body condition score (BCS (OR= 3.642; P= 0.018. Furthermore, estrus synchronization protocol (OR= 1.774; P= 0.083 and the absence of corpus luteum (CL at the initiation of treatment (OR= 0.512; P= 0.061 had a tendency to affect the conception rate, while age (OR= 0.715; P= 0.008 was a protective factor to conception rate.  In conclusion, positive daily weight gain before AI or ET, higher BCS, younger age, and the presence of CL at the initiation of estrus synchronization in dairy heifers increased the likelihood to conceive.

  14. Balanço de nitrogênio em fêmeas leiteiras em confinamento alimentadas com concentrado à base de farelo de soja ou farelo de algodão Nitrogen use efficiency of growing dairy heifers fed concentrate rations based on soybean or cottonseed meal

    Directory of Open Access Journals (Sweden)

    Stefanie Alvarenga Santos

    2010-05-01

    did not change the levels of ureic nitrogen in the plasma. Levels of concentrate and protein sources did not affect concentrations of total purine and allantoin in the urine, the percentage of allantoin regarded to total purine, the levels of uric acid in the urine, microbial nitrogen neither the microbial efficiency. The supply of 1 or 2 kg of concentrate ration for growing dairy heifers, using soybean meal or cottonseed meal as protein sources does not affect microbial efficiency, although the supply of 2 kg of concentrate ration causes N waste in feces.

  15. Haematological studies of Gaolao Heifers

    Directory of Open Access Journals (Sweden)

    P.M.Kapale,D.G.Jagtap

    2008-02-01

    Full Text Available Hematological study of 15 healthy Gaolao heifers has been carried out. The mean ±S.E. values of total erythrocyte (10.3 ±0.34 million/cu mm, Hb (11.92 ±0.33 gm%, PCV (34.07±1.11%, MCV (33.14±0.75cuμ, MCH (11.63±0.32 μμgm, MCHC (35.07 ±0.70%,TLC (9.51±0.92 thousand/cmm, Lymphocytes (64.93 ±1.74%,Neutrophil (28.93 ±1.8%, Monocyte (2.2 ±0.34%, Basophil (0.2±0.11 and Eosinophil (3.7 ± 0.44% have been reported. [Veterinary World 2008; 1(1.000: 16-16

  16. Short communication: Development of the first follicular wave dominant follicle on the ovary ipsilateral to the corpus luteum is associated with decreased conception rate in dairy cattle.

    Science.gov (United States)

    Miura, R; Haneda, S; Kayano, M; Matsui, M

    2015-01-01

    In this study, we examined the effect of the locations of the first-wave dominant follicle (DF) and corpus luteum (CL) on fertility. In total, 350 artificial insemination (AI) procedures were conducted (lactating dairy cows: n=238, dairy heifers: n=112). Ovulation was confirmed 24 h after AI. The locations of the first-wave DF and CL were examined 5 to 9d after AI using rectal palpation or transrectal ultrasonography. Lactating dairy cows and dairy heifers were divided into 2 groups: (1) the ipsilateral group (IG), in which the DF was ipsilateral to the CL; and (2) the contralateral group (CG), in which the DF was contralateral to the CL. Pregnancy was diagnosed using transrectal ultrasonography 40d after AI. Conception rates were 54.0% in all cattle: 48.9% in lactating dairy cows, and 58.9% in dairy heifers. The incidence of the first-wave DF location did not differ between IG and CG (all cattle: 184 vs. 166; lactating cows: 129 vs. 109; heifers: 55 vs. 57 for IG vs. CG). Conception rates were lower in IG than in CG (all cattle: 40.2 vs. 69.3%; lactating dairy cows: 38.0 vs. 67.0%; dairy heifers: 45.5 vs. 73.7%, for IG vs. CG). Conception rate was not affected by season or live weight in heifers and lactating cows. In addition, days in milk at AI, milk production, body condition score, and parity did not affect conception in lactating cows. In summary, development of the first-wave DF in the ovary ipsilateral to the CL was associated with reduced conception rates in both lactating cows and heifers.

  17. Environmental and animal factors associated with gestation length in Holstein cows and heifers in two herds in the Czech Republic.

    Science.gov (United States)

    Tomasek, R; Rezac, P; Havlicek, Z

    2017-01-01

    The objective was to assess the effects of the month of conception, month of calving, sex of the calf, and twins on gestation length (GL) in Holstein cows and heifers in two dairy herds with different milk yields. The study was performed in northeast Czech Republic over a 6-year period on two commercial dairy herds with a mean annual milk production of 11,060 kg per cow in the higher milk-producing herd and 8854 kg per cow in the lower milk-producing herd. Gestation length in cows that conceived in different months of the year was longer in the higher milk-producing herd than that in the lower milk-producing herd throughout the year (P Gestation length in cows that conceived in different months of the year was longer than that in heifers through the whole year in both herds (P Gestation length in cows and heifers that conceived in the first months of the year was longer than in those that conceived in the last months of the year in both herds (P Gestation length in cows and heifers that calved in late fall and throughout winter was longer than in those that calved in spring and summer in both herds (P Gestation length in females carrying male calves was longer than in those carrying female calves (P Gestation length in cows (P < 0.0001) and heifers (P < 0.05) carrying singles was longer than in those carrying twins in both herds. In conclusion, results indicate that GL in Holstein cattle is associated with the month of conception, month of calving, herd, parity, sex of the calf, and twins.

  18. Analysis of genetic diversity and population structure in Argentine and Bolivian Creole cattle using five loci related to milk production

    Directory of Open Access Journals (Sweden)

    Lirón J.P.

    2002-01-01

    Full Text Available Data from five protein-coding loci related to dairy production were used to study the genetic diversity and population structure of Argentine and Bolivian Creole cattle breeds. Genomic DNA was extracted from blood samples of six Creole cattle breeds: Argentine (n = 230, Patagonian (n = 25; "Saavedreño" (n = 140, "Chaqueño Boliviano" (n = 30, "Yacumeño" (n = 27, and "Chusco" (n = 11. kappa-casein, beta-lactoglobulin, growth hormone and prolactin were measured by PCR-RFLP, while alphaS1-casein was typed by PCR-ASO. The results are discussed, focusing on: historical origin, recent differentiation and selection events, Zebu gene introgression, and population structure. This work shows that: (i For the studied genes, the observed gene frequency profiles of Argentine and Bolivian Creole cattle breeds were close to the data reported for Iberian breeds and for other South-American Creole cattle breeds which are historically related; (ii although Zebu gene introgression has been reported at the studied loci, these breeds seem to be far from the Zebu gene frequency profiles; and (iii the Argentine and Bolivian Creole cattle showed significant levels of subdivision, but each population has maintained its degree of genetic variability.

  19. Synchronization and Artificial Insemination Strategies in Dairy Herds.

    Science.gov (United States)

    Stevenson, Jeffrey S

    2016-07-01

    Timed artificial insemination (AI) programs are commonly used in the dairy industry for lactating cows, but less so in replacement heifers. Excellent programs using combinations of prostaglandin F2α and gonadotropin-releasing hormone in protocols relying on timed AI without detection of estrus or in protocols that combine timed AI with inseminations performed after detected estrus are able to achieve acceptable pregnancy percentages. In herds with excellent estrus detection, timed AI programs serve as a failsafe system to address cows or heifers not yet inseminated after a defined period of estrus detection.

  20. 9 CFR 78.6 - Steers and spayed heifers.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Steers and spayed heifers. 78.6... Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.6 Steers and spayed heifers. Steers and spayed heifers may be moved interstate without restriction under this subpart....

  1. 9 CFR 78.21 - Bison steers and spayed heifers.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Bison steers and spayed heifers. 78.21... Restrictions on Interstate Movement of Bison Because of Brucellosis § 78.21 Bison steers and spayed heifers. Bison steers and spayed heifers may be moved interstate without restriction under this subpart....

  2. Growth parameters of Holstein-Friesland heifers reared on complete ...

    African Journals Online (AJOL)

    Unknown

    balanced complete diets were formulated for heifers of different age groups, i.e. ... had higher (P < 0.01) condition scores than heifers fed diets containing other roughages. .... The effect of roughage source on DM intake is presented in Table 2. ..... heifers at calving are not desired because such animals have poor appetites, ...

  3. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

    Vogel, Valerie; Pedersen, Jes Søe; Giraud, Tatiana;

    2010-01-01

    ) and secondary introductions (from sites with established invasive supercolonies) were important in the global expansion of the Argentine ant. In combination with the similar social organization of colonies in the native and introduced range, this indicates that invasiveness did not evolve recently as a unique...

  4. Structural changes in dairy business in Croatia

    Directory of Open Access Journals (Sweden)

    Teo Vujčić

    2005-01-01

    Full Text Available Croatia today is in the economy transition process that also includes agriculture aiming to increase production and achieving competitive standard with international and European markets. Currently, domestic cow milk production ensures 80% of annual milk and dairy products requirements with the 20% import. In the period from 1990-1992, during the patriot war, 103000 cows and heifers were destroyed. Since then, Croatia started the gradual process of reorganization of the agricultural private sector including dairy business in order to increase production insensitivity.The agricultural structure of dairy segment is unsatisfactory with only 23.39% of farms holding four or more heifers. Households with 3 cows per farm dominate with average real estate of 0.10-3.0 acres.Changes in milk production (1990-2003 are reflected in the decrease of the number of breeding cattle – index 56.13%, and decrease of milk market producers from 65 000 to 65 151. Never the less, positive trends towards stabilization in milk production (2003 – 642 mil litres and annual milk intake increased from 342 mil litres in 1990 to 472 mil litres in 2003 (index 138.08% can be noticed. Changes in the structure of milk producers show certain positive movements as 23.39% of producers have 53.40% cows and respectively participation in milk production and buy off. Until 2008, with determined development conditions, cow milk production can increase for 42% and from 2703 litres to average of 4000 litres per dairy cow.

  5. 后备奶牛磷减排的营养措施%Research Advances in Phosphorus Emission Reduction in Holstein Heifers

    Institute of Scientific and Technical Information of China (English)

    张彬; 杨金勇; 韦子海; 刘建新; 刘红云

    2014-01-01

    As the lack of research in phosphorus requirement of heifer nowadays,the content of phosphorus in heifer diet used in production is often higher than required,which results in serious environmental pollution by the excretion of excessive phosphorus. This paper reviewed the key roles of phosphorus in dairy cows’produc-tion,the recommendations of phosphorus content in heifer diet in different feeding standards,current situation of phosphorus excretion and related problems in scaled dairy farms,and discussed some effective nutritional ways to reduce phosphorus emission of heifers.%目前,后备奶牛磷需要量的研究相对较少,生产中饲粮磷含量普遍偏高,未被吸收的磷通过粪尿形式排放后对环境造成了严重污染。本文综述了磷元素在奶牛生产中的重要作用、不同饲养标准对后备奶牛饲粮磷含量的推荐值,阐述了规模化奶牛场磷排放现状及其对环境的影响,并探讨了减少后备奶牛磷排放的营养措施。

  6. Malvinas: the Argentine Perspective of the Falkland’s Conflict

    Science.gov (United States)

    2010-05-01

    Guerra de las Malvinas:Historical background of the Malvinas Conflict. (Buenos Aires-Argentina: Circulo Militar, 1989), 121. 3 Argentine Army...the Argentine Air Force among others. Other important Argentine sources in general are: Carlos Landaburu’s La Guerra de las Malvinas : Historical... Guerra de las Malvinas : Historical background of the Malvinas Conflict (Buenos Aires-Argentina: Circulo Militar, 1988), 21. Port Egmond was a part of

  7. 75 FR 53731 - Culturally Significant Objects Imported for Exhibition Determinations: “Contemporary Argentine...

    Science.gov (United States)

    2010-09-01

    ... for Exhibition Determinations: ``Contemporary Argentine Masterworks'' SUMMARY: Notice is hereby given... hereby determine that the objects to be included in the exhibition ``Contemporary Argentine...

  8. Evaluation of physical structure value in spring-harvested grass/clover silage and hay fed to heifers

    DEFF Research Database (Denmark)

    Schulze, A.K.S.; Nørgaard, P.; Byskov, M.V.;

    2015-01-01

    The physical structure value of conserved grass/clover forages of spring harvest was evaluated by assessing effects of harvest time, conservation method, iNDF/NDF ratio and NDF intake (NDFI) per kg BW on chewing activity and fecal particle size in dairy heifers. A mixed sward consisting of ryegrass...... of 315, 436, 414 and 503 g/kg DM, respectively. Forages were fed as sole feed to four Jersey heifers of 435±30 kg BW in a 4×4 Latin square experiment. Feeding level was 90% of individual ad libitum intake, divided equally across two daily meals offered at 0800 and 1530 h. Chewing activity was estimated......, and suggests implementation of NDFI per kg BW in systems evaluating physical structure in diets....

  9. Combined use of progesterone inserts, ultrasongraphy, and GnRH to identify and resynchronize nonpregnant cows and heifers 21 days after timed artificial insemination.

    Science.gov (United States)

    Kelley, D E; Ibarbia, L; Daetz, R; Bittar, J H; Risco, C A; Santos, J E P; Ribeiro, E S; Galvão, K N

    2016-01-15

    The objective was to decrease the reinsemination interval (RI) when dairy cows and heifers are inseminated using all timed artificial insemination (TAI) programs. Holstein cows (n = 211) and heifers (n = 153) were randomly assigned to a control or 21-day Resynch (21dRES) at 13 days after TAI. Animals in 21dRES (n = 109 cows and 77 heifers) had a progesterone device inserted on Day 13 and removed on Day 20 after TAI and ovaries scanned by ultrasonography. Animals found not to have an active CL (<15 mm) or a CL that decreased 10 mm or greater from Days 13 to 20, and to have a follicle of 12 mm or greater received GnRH and TAI on Day 21. Pregnancy diagnosis was performed on Day 32. Nonpregnant control cows (n = 102) were resynchronized immediately using Ovsynch-56, and control heifers (n = 76) were resynchronized using 5-day Cosynch starting on Day 34; therefore, cows and heifers were reinseminated on Day 42. Nonpregnant 21dRES animals that had not been reinseminated on Day 21 were resynchronized concurrently with the control animals. Pregnancy per AI (PAI) for the initial TAI was similar (P = 0.80) for 21dRES and control cows (30.3% vs. 29.4%) and heifers (49.4% vs. 51.3%). Of the nonpregnant 21dRES animals, 33 of 76 cows (43.4%) and 22 of 39 heifers (56.4%) had been reinseminated on Day 21. Therefore, the RI was decreased by 9.9 days (33.3 ± 1.0 vs. 43.2 ± 1.0 days; P < 0.001) in 21dRES cows and by 12.2 days in 21dRES heifers (30.1 ± 1.3 vs. 42.3 ± 1.3 days; P < 0.001) compared with controls. The overall resynchronized PAI was similar for 21dRES cows compared with controls (31.6% vs. 25.0%; P = 0.23). The PAI was 24.2% for 21dRES cows reinseminated on Day 21 and 37.2% for 21dRES cows reinseminated on Day 42. The overall resynchronized PAI was increased for 21dRES heifers compared with controls (57.5% vs. 32.4%; P = 0.03) because 21dRES heifers reinseminated on Day 21 had similar PAI compared with controls (43.5% vs. 32

  10. Argentine hemorrhagic fever: a primate model.

    Science.gov (United States)

    Weissenbacher, M C; Calello, M A; Colillas, O J; Rondinone, S N; Frigerio, M J

    1979-01-01

    Experimental Junin virus infection of a New World primate, Callithrix jacchus, was evaluated. The virus produced anorexia, loss of weight, thrombocytopenia, leukopenia, and hemorrhagic and neurological symptoms and terminated in death. Virus was recovered from urine, blood samples and all tissues taken at autopsy. These preliminary observations show that several aspects of the experimental disease in C. jacchus are quite similar to severe natural Argentine hemorrhagic fever of man.

  11. Physiology and Endocrinology Symposium: Nutritional aspects of developing replacement heifers.

    Science.gov (United States)

    Funston, R N; Martin, J L; Larson, D M; Roberts, A J

    2012-04-01

    Studies in numerous species provide evidence that diet during development can mediate physiological changes necessary for puberty. In cattle, several studies have reported inverse correlations between postweaning growth rate and age at puberty and heifer pregnancy rates. Thus, postweaning growth rate was determined to be an important factor affecting age of puberty, which in turn influences pregnancy rates. This and other research conducted during the late 1960s through the early 1980s indicated puberty occurs at a genetically predetermined size, and only when heifers reach their target BW can increased pregnancy rates be obtained. Guidelines were established indicating replacement heifers should achieve 60 to 65% of their expected mature BW by breeding. Traditional approaches for postweaning development of replacement heifers used during the last several decades have primarily focused on feeding heifers to achieve or exceed an appropriate target BW and thereby maximize heifer pregnancy rates. Intensive heifer development systems may maximize pregnancy rates, but not necessarily optimize profit or sustainability. Since inception of target BW guidelines, subsequent research demonstrated that the growth pattern heifers experience before achieving a critical target BW could be varied. Altering rate and timing of BW gain can result in compensatory growth periods, providing an opportunity to decrease feed costs. Recent research has demonstrated that feeding replacement heifers to traditional target BW increased development costs without improving reproduction or subsequent calf production relative to development systems in which heifers were developed to lighter target BW ranging from 50 to 57% of mature BW.

  12. Immunisation of smallholder dairy cattle against anaplasmosis and babesiosis in Malawi

    DEFF Research Database (Denmark)

    Tjørnehøj, Kirsten; Lawrence, J. A.; Kafuwa, P. T.

    1997-01-01

    A field study was conducted in the Southern Region of Malawi to evaluate the possible benefits of immunisation of improved dairy cattle against Anaplasma marginale, Babesia bigemina and Babesia bovis. Friesian crossbred heifers were immunised when they were being reared on Government farms...

  13. Nutrient digestion, microbial protein synthesis, and blood metabolites of Jersey heifers fed chitosan and whole raw soybeans

    Directory of Open Access Journals (Sweden)

    Jefferson Rodrigues Gandra

    2016-03-01

    Full Text Available ABSTRACT This study was undertaken to determine the effects of chitosan and whole raw soybean on nutrient intake and total tract digestion, nitrogen utilization, microbial protein synthesis, blood metabolites, and energy balance of dairy heifers. Twelve Jersey heifers (6±0.5 months of age and 139.50±25.56 kg of live weight; mean ± standard deviation were randomly assigned to a replicated Latin square design with a 2 × 2 factorial arrangement. The experimental period consisted of 14 days of adaptation to diets, six days of sampling, and five days of washout. The experimental diets were: control (CO; chitosan (CHI, inclusion of 2.0 g kg−1 DM of chitosan; whole raw soybean (WS, 163.0 g kg−1 of WS on diet DM basis; and chitosan + whole raw soybean (CHI+WS. Chitosan decreased dry matter and neutral detergent fiber intakes; however, CHI increased DM total tract digestion. An interaction effect was observed on retained nitrogen, which increased when animals were fed CHI+WS compared with CO or CHI, but did not differ from that of animals fed WS. Chitosan decreased microbial nitrogen and crude protein flow of heifers. Energy balance was improved when heifers received diets containing WS. Efficiency of energy utilization was not affected by experimental diets. An interaction effect was observed for blood high-density lipoprotein (HDL concentration, which increased with both dietary inclusion of CHI and WS compared with the other diets, and CHI provided the lowest value of HDL cholesterol. Chitosan and whole raw soybean do not alter nutrient intake and total tract digestion; however, they decrease nitrogen urinary excretion and increase blood HDL cholesterol of heifers.

  14. Effects of two different blends of naturally mycotoxin-contaminated maize meal on growth and metabolic profile in replacement heifers.

    Science.gov (United States)

    Abeni, F; Migliorati, L; Terzano, G M; Capelletti, M; Gallo, A; Masoero, F; Pirlo, G

    2014-10-01

    The aim of this trial was to assess the effects of the administration of different combinations of mycotoxins in naturally contaminated maize grains on dairy heifer growth, blood measurements and puberty onset. A total of 35 Friesian female heifers were randomly allotted to three experimental groups from 18-21 to 42-45 weeks of age. During the 24-week experimental period (EP), heifers were fed the same diet, but with maize meal derived from three differently contaminated lots: very low contamination, as control (C); medium-low aflatoxin-contaminated (A); and mixed aflatoxin-fumonisin contaminated (A-F). At the end of the EP, they returned to a common diet without contaminated maize, and they were monitored for an additional period of 12 weeks (post-experimental period, PEP). BW, wither height, hip height, body length and heart girth were measured every 4 weeks from the beginning of EP to the end of PEP. At the same time, body condition score was evaluated and blood samples were taken from the jugular vein to be analysed for haematological, serum protein and metabolic profiles. Age at puberty was assessed by measuring weekly plasma progesterone levels from 40 to 52 weeks of age. Body growth measurements were processed both by ANOVA of average daily gain of EP and PEP separately, and by the analysis of growth curve parameters. Haematological, serum protein and metabolic profile were evaluated using a mixed model, taking into account the repeated measurements in time on each animal. Heifers' growth was delayed both in A and A-F groups during EP, as evidenced by the different linear coefficients of the BW growth curve in the three groups. Differently contaminated diets did not affect the haematological profile, so that it can be concluded that these levels of mycotoxin contamination do not determine any specific effect on haematopoiesis and immunity in growing heifers. The main blood marker of mycotoxin chronic toxicity was the γ-glutamyl transferase activity level in

  15. Effect of heifer frame score on growth, fertility, and economics.

    Science.gov (United States)

    Şentürklü, S; Landblom, D G; Perry, G A; Petry, T

    2015-01-01

    A non-traditional forage-based protocol was employed to evaluate replacement heifer growth, fertility, and economics between small frame (SF, 3.50; n = 50) and large frame (LF, 5.56; n = 50) heifers using three increasing gain growth phases. Preceding an 85 d growing-breeding period (Phase 3; P3) the heifers were managed as a common group for Phases 1 and 2 (P1 and P2). During P1, heifers grazed common fields of unharvested corn and corn residue (total digestible nutrients [TDN] 56%) with supplemental hay. For P2, heifers grazed early spring crested wheatgrass pasture (CWG; TDN 62%) that was followed by the final P3 drylot growing and breeding period (TDN 68%). Small frame heifers were lighter at the end of P1 in May and at the start of P3 breeding in August (p = 0.0002). Percent of mature body weight (BW) at the end of P1 (209 d) was 48.7% and 46.8%, respectively, for the SF and LF heifers and the percent pubertal was lower for SF than for LF heifers (18.0% vs 40.0%; p = 0.02). At breeding initiation (P3), the percentage of mature BW was 57.8 and 57.2 and the percentage pubertal was 90.0 and 96.0 (p = 0.07) for the SF and LF heifers, respectively; a 5-fold increase for SF heifers. Breeding cycle pregnancy on days 21, 42, and 63, and total percent pregnant did not differ (p>0.10). In drylot, SF heifer dry matter intake (DMI) was 20.1% less (p = 0.001) and feed cost/d was 20.3% lower (p = 0.001), but feed cost/kg of gain did not differ between SF and LF heifers (p = 0.41). Economically important live animal measurements for muscling were measured in May and at the end of the study in October. SF heifers had greater L. dorsi muscle area per unit of BW than LF heifers (p = 0.03). Small frame heifer value was lower at weaning (p = 0.005) and the non-pregnant ending heifer value was lower for SF heifers than for the LF heifers (p = 0.005). However, the total development cost was lower for SF heifers (p = 0.001) and the net cost per pregnant heifer, after accounting for

  16. Effect of Heifer Frame Score on Growth, Fertility, and Economics

    Science.gov (United States)

    Şentürklü, S.; Landblom, D. G.; Perry, G. A.; Petry, T.

    2015-01-01

    A non-traditional forage-based protocol was employed to evaluate replacement heifer growth, fertility, and economics between small frame (SF, 3.50; n = 50) and large frame (LF, 5.56; n = 50) heifers using three increasing gain growth phases. Preceding an 85 d growing-breeding period (Phase 3; P3) the heifers were managed as a common group for Phases 1 and 2 (P1 and P2). During P1, heifers grazed common fields of unharvested corn and corn residue (total digestible nutrients [TDN] 56%) with supplemental hay. For P2, heifers grazed early spring crested wheatgrass pasture (CWG; TDN 62%) that was followed by the final P3 drylot growing and breeding period (TDN 68%). Small frame heifers were lighter at the end of P1 in May and at the start of P3 breeding in August (p = 0.0002). Percent of mature body weight (BW) at the end of P1 (209 d) was 48.7% and 46.8%, respectively, for the SF and LF heifers and the percent pubertal was lower for SF than for LF heifers (18.0% vs 40.0%; p = 0.02). At breeding initiation (P3), the percentage of mature BW was 57.8 and 57.2 and the percentage pubertal was 90.0 and 96.0 (p = 0.07) for the SF and LF heifers, respectively; a 5-fold increase for SF heifers. Breeding cycle pregnancy on days 21, 42, and 63, and total percent pregnant did not differ (p>0.10). In drylot, SF heifer dry matter intake (DMI) was 20.1% less (p = 0.001) and feed cost/d was 20.3% lower (p = 0.001), but feed cost/kg of gain did not differ between SF and LF heifers (p = 0.41). Economically important live animal measurements for muscling were measured in May and at the end of the study in October. SF heifers had greater L. dorsi muscle area per unit of BW than LF heifers (p = 0.03). Small frame heifer value was lower at weaning (p = 0.005) and the non-pregnant ending heifer value was lower for SF heifers than for the LF heifers (p = 0.005). However, the total development cost was lower for SF heifers (p = 0.001) and the net cost per pregnant heifer, after accounting for

  17. Malignant catarrhal fever infection in a heifer in Jordan

    Directory of Open Access Journals (Sweden)

    Sameeh M. Abutarbush

    2016-08-01

    Full Text Available A 14-month-old Holstein Friesian heifer was presented for decreased appetite, ocular discharge, and diarrhea. The heifer was raised at the farm since she was 3 days old. On presentation, the heifer had bilateral mucopurulent ocular discharge and corneal opacity, ulcerative and necrotic skin, and enlarged superficial lymph nodes. Malignant catarrhal fever (MCF infection was diagnosed based on clinical signs and PCR. MCF infection has never been reported in Jordan.

  18. The worldwide expansion of the Argentine ant

    DEFF Research Database (Denmark)

    Vogel, Valerie; Pedersen, Jes Søe; Giraud, Tatiana

    2010-01-01

    DNA haplotypes also suggests that supercolonies in the introduced range each derive from a single source supercolony and that one of these source supercolonies has been particularly successful, being the basis of many introduced populations spread across the world. Comparison of the genetic diversity......Aim The aim of this study was to determine the number of successful establishments of the invasive Argentine ant outside native range and to see whether introduced supercolonies have resulted from single or multiple introductions. We also compared the genetic diversity of native versus introduced...... to possible strategies to be used to control invasive ants....

  19. Evaluating the reproductive performance of British beef and dairy herds using national cattle movement records.

    Science.gov (United States)

    Gates, M C

    2013-11-23

    National cattle movement databases provide a valuable opportunity to monitor the reproductive performance of breeding cattle on an industry-wide scale. In this analysis, records from the Cattle Tracing System database were used to derive key measures of reproductive efficiency for British beef and dairy herds, including calving spread, age at first calving, calving interval, culling rate and calf mortality rate. At the animal level, only 8.5 per cent of beef heifers and 6.9 per cent of dairy heifers calved by the target age of 24 months. The average calving interval was 394 days for beef dams (median: 371) and 426 days for dairy dams (median: 400). Differences in performance were noted between cattle breeds. An estimated 43.9 per cent calves born in dairy herds were crossbreed beef animals, which may limit the availability of replacement dairy heifers. At the herd level, calving spread and calf mortality rates increased with herd size, while average age at first calving, calving interval, and crossbreeding generally decreased with herd size. Dam age, calving month, breed and twinning were significant risk factors for culling and calf mortality at the animal level. Wide variation in performance between individual herds highlights the potential for improving the efficiency of British cattle production.

  20. COMPARISON ON ACCURACY OF LOGISTIC, GOMPERTZ AND VON BERTALANFFY MODELS IN PREDICTING GROWTH OF NEW BORN CALF UNTIL FIRST MATING OF HOLSTEIN FRIESIAN HEIFERS

    Directory of Open Access Journals (Sweden)

    L. Budimulyati S.

    2014-10-01

    Full Text Available The body weight records of 1221 heifers were used in this study collected from PT Taurus DairyFarm Sukabumi from year 2001 until 2011. The records that could be used for analysis were 373 out of1221 heifers, having completed data from birth to first mating period. Three different models i.e,Logistic, Gompertz, and von Bertalanffy were performed to analyze the growth rate of heifers. Theresults showed that the three models had different accuracy and heavily depend on age, environment andduration of recording. The body weights of sexual maturity and on certain ages were affected by theduration of recording. The Gompertz model was performed as the simpliest model in form ofcalculation. On the other hand, the Logistic was more difficult to calculate. All models indicated highaccuracy with the determination coefficient (R2 more than 90%. Based on the comparison, theGompertz and Logistic model are recommended for predicting the growth rate of heifers from birth tosexual maturity.

  1. Impact of reproductive technologies on dairy food production in the dairy industry.

    Science.gov (United States)

    Stevenson, Jeffrey S

    2014-01-01

    Reproductive technologies drive the efficiency of managing dairy cows because the lactation cycle of the dairy cow depends on regular calving to renew lactation yields. Achieving timely pregnancies to allow calving every 12-14 months, therefore, is critical in modern dairy production. To meet the demands to produce sufficient milk for fluid and dairy products, various technologies are applied to enhance efficiencies on the dairy farm. Artificial insemination (AI), embryo transfer, ultrasonographic and chemical detection of pregnancy, various monitors that detect or predict estrus, and handheld communication and testing devices allow managers to retrieve information to make cow-side decisions about health and reproductive status. Genomic testing of young potential sires or young heifers is now possible and can provide information about their genetic merit years before any progeny tests can be completed. In many countries, the challenge faced by dairy producers is their ability to afford these technologies in the face of rising feed and labor costs and volatile milk prices received at the farm gate. Government policies often place obstacles, trade barriers, and unfunded mandates that preclude operations from making a modest profit. Unlike nearly all other manufacturing industries, agriculture producers have little control over the price received for their products. Therefore, dairy production is vulnerable to many uncontrolled factors including climate, government policy, economic conditions, and skilled labor shortages. It is clear that the impact of emerging and current reproductive technologies is critical to the management of dairy cattle to produce sufficient milk to meet consumer demands for quality fluid and dairy products.

  2. Where and how Argentine ant (Linepithema humile) spreads in Corsica?

    Science.gov (United States)

    Blight, Olivier; Orgeas, Jérôme; Renucci, Marielle; Tirard, Alain; Provost, Erick

    2009-08-01

    The Argentine ant, Linepithema humile (Dolichoderinae), is one of the most widespread invasive ant species in the world. When established in optimal habitat, this species usually excludes most other local ants and can heavily impact other arthropods as well. Although Argentine ants have been present in southern Europe for more than 100 years, they were first noted in Corsica, a French Mediterranean island, in 1957 in only one urban station. In this study, we aimed to map precisely their geographical distribution in Corsica and to quantify their presence by using an infestation index. We recorded changes in the distribution of Argentine ants in Corsica over the past decade. Argentine ants appeared to be well established within their introduced range and spreading along the Corsican coasts principally through Human-mediated jump-dispersal but not homogenously.

  3. Exploration of Possible Astroblemes in the Argentine Puna

    Science.gov (United States)

    Acevedo, R. D.; Alonso, R.; Rocca, M.; Klajnik, K.; Tálamo, E.

    2014-09-01

    Potential three new astrobleme sites have been detected by remote sensors and checked in situ in Argentine Puna: an elevated plateau that it has remained stable and invariable across long geological periods.

  4. Framing crime: moral panic in Argentine newspapers

    Directory of Open Access Journals (Sweden)

    Natalia ARUGUETE

    2013-01-01

    Full Text Available Carolina Píparo was shot a few minutes after withdrawing cash from a bank branch. This case outraged the public opinion because she was eight months pregnant at the moment of the assault. She had to undergo a caesarean section and her baby only survived one week. Through an exploratory and inductive research we will analyze how the Argentine newspapers presented the case. We aim at elaborating a content analysis code book that can be validated in future similar researches on the subject. We apply the Framing theory in order to detect the frames used in the news coverage and to observe if they are compatible with the idea of «moral panic» proposed by Stanley Cohen.

  5. Dairy development

    NARCIS (Netherlands)

    Leegwater, P.; Hoorweg, J.C.

    2000-01-01

    The growth of the dairy sector as it has occurred in Kilifi and Malindi Districts is one of the few examples of successful agricultural development in the coastal region in the past decades. Between 1985 and 1997 dairy cattle have more than doubled in number. Three livestock systems are described:

  6. Sustaining dairy

    NARCIS (Netherlands)

    Villarreal Herrera, Georgina

    2017-01-01

    Dairy in Europe has undergone many changes in the last few years—the abolition of milk production quotas being a fundamental one. This study explores these changes in relation to the sustained social and environmental viability of the sector and how dairy processors' sustainability

  7. Seasonal differences in the parameters of luteinizing hormone release to exogenous gonadotropin releasing hormone in prepubertal Holstein heifers in Sapporo.

    Science.gov (United States)

    Kadokawa, Hiroya

    2007-02-01

    Stress due to summer heat has adverse effects on reproduction in Holstein dairy cattle. Summer suppression of reproduction of Holsteins can pose an important economic problem, even in Hokkaido prefecture located in the northern region of Japan. Hokkaido is one of the most important dairy farming areas of Japan. This study is an attempt to clarify the seasonal differences in the parameters of luteinizing hormone (LH) response to exogenous gonadotropin releasing hormone (GnRH) in Sapporo, Hokkaido, Japan. A total of 12 prepubertal heifers received an injection with GnRH analogue intramuscularly in either May (n=4, May group), July (n=4, July group), or November (n=4, November group), and serial blood samples were collected to analyze the parameters of the LH response curve after GnRH injection. The parameters were as follows: the basal LH concentration, peak LH concentration, duration from the time of GnRH injection to the time of the peak LH concentration, and area under the LH response curve (AUC). There were no significant differences in the basal and peak LH concentrations or the AUC among the three groups. The July group reached the LH peak significantly (P<0.05) faster than the May group, but there was no significant difference with the November group. Therefore, the results of the present study do not demonstrate an effect of summer heat on the LH response to the exogenous GnRH in Holstein heifers.

  8. Different true-protein sources do not modify the metabolism of crossbred Bos taurus × Bos indicus growing heifers

    Directory of Open Access Journals (Sweden)

    Diego Azevedo Mota

    2015-02-01

    Full Text Available The present study was conducted to investigate the effect of alternative true-protein sources to soybean meal, with different ruminal degradability, using a sugarcane-based diet, on nutrient digestion, ruminal fermentation, efficiency of microbial protein synthesis and passage rate in prepubertal dairy heifers. Eight crossbred rumen- and duodenum-cannulated Holstein × Gyr dairy heifers (202.0±11.5 kg BW were evaluated in a 4 × 4 Latin square experimental design with four treatments and four periods in two simultaneous replicates. Dietary treatments were: soybean meal; cottonseed meal; peanut meal; and sunflower meal. When associated with diets containing sugarcane, the different protein sources did not affect intake or digestibility of dry mater, crude protein, organic matter and neutral detergent fiber. The average ruminal pH, NH3-N and concentration of total volatile fatty acids were not different among the diets supplied. The concentration of butyric acid was different among the protein sources, wherein the animals fed the diet with sunflower meal presented lower values than those fed the other sources. Diets did not affect nitrogen balance, microbial nitrogen, microbial synthesisefficiency, estimated dry matter flow, or passage rate. Alternative protein sources can be used to reduce the costs without changing the animal metabolism.

  9. Pheromone disruption of Argentine ant trail integrity

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Manning, L.M.; Stringer, L.D.; Cappadonna, J.; El-Sayed, A. M.

    2008-01-01

    Disruption of Argentine ant trail following and reduced ability to forage (measured by bait location success) was achieved after presentation of an oversupply of trail pheromone, (Z)-9-hexadecenal. Experiments tested single pheromone point sources and dispersion of a formulation in small field plots. Ant walking behavior was recorded and digitized by using video tracking, before and after presentation of trail pheromone. Ants showed changes in three parameters within seconds of treatment: (1) Ants on trails normally showed a unimodal frequency distribution of walking track angles, but this pattern disappeared after presentation of the trail pheromone; (2) ants showed initial high trail integrity on a range of untreated substrates from painted walls to wooden or concrete floors, but this was significantly reduced following presentation of a point source of pheromone; (3) the number of ants in the pheromone-treated area increased over time, as recruitment apparently exceeded departures. To test trail disruption in small outdoor plots, the trail pheromone was formulated with carnuba wax-coated quartz laboratory sand (1 g quartz sand/0.2 g wax/1 mg pheromone). The pheromone formulation, with a half-life of 30 h, was applied by rotary spreader at four rates (0, 2.5, 7.5, and 25 mg pheromone/m2) to 1- and 4-m2 plots in Volcanoes National Park, Hawaii. Ant counts at bait cards in treated plots were significantly reduced compared to controls on the day of treatment, and there was a significant reduction in ant foraging for 2 days. These results show that trail pheromone disruption of Argentine ants is possible, but a much more durable formulation is needed before nest-level impacts can be expected. ?? 2008 Springer Science+Business Media, LLC.

  10. Effect of heifer-raising practices on E. coli antimicrobial resistance and Salmonella prevalence in heifer raisers.

    Science.gov (United States)

    Pereira, R V; Siler, J D; Cummings, K J; Davis, M A; Warnick, L D

    2015-11-01

    Although cattle movement and commingling play an important role in the inter-herd transmission of pathogens, little is known about the effect of commingling of heifers at raising operations. The objective of this study was to compare the resistance of E. coli and prevalence of Salmonella from pooled faecal pats of heifers raised off-farm at multi-source raisers (MULTI) that raised heifers from at least two farms compared with on-farm raisers (HOME), with heifers from only that farm. MULTI faecal pat samples were collected from pens with animals that had arrived at the farm within the previous 2 months (AP) and from animals that would be departing the heifer raiser in 2-3 months (DP). Corresponding age sampling was conducted at HOME raisers. Odds of ampicillin resistance were 3·0 times greater in E. coli collected from MULTI compared to HOME raisers. E. coli from AP pens had significantly (P Salmonella recovery was not significantly different between heifer-raising systems (P = 0·3). Heifer-raising system did not have a major overall impact on selection of resistant E. coli, which was strongly affected by the age of the animals sampled.

  11. Genetic evaluation of reproductive performance in Canadian dairy cattle

    Directory of Open Access Journals (Sweden)

    F. Miglior

    2010-04-01

    Full Text Available A new genetic evaluation system for the reproductive performance of dairy cattle has been developed in Canada. The evaluation system includes all traits related to reproductive performance, namely age at first service as a heifer trait, interval from calving to first service for cows and 7 traits each for both heifers and cows (56-days non return rate, interval from first service to conception, number of services to conception, gestation length, direct and maternal calving ease, direct and maternal calf survival and direct and maternal calf size. The model of analysis is a 16-trait animal model with different fixed effects according to the analyzed trait. Two indices for daughter fertility and calving performance have been developed. The impact of including the two indices in the national selection index was assessed.

  12. Understanding Swedish dairy farmers’ view on breeding goals

    DEFF Research Database (Denmark)

    Röcklinsberg, H.; Gamborg, Christian; Gjerris, Mickey;

    2016-01-01

    , but also problems related to resources like milking system or grazing and to management practices like herd size or pasture management. Farmers’ practice varies depending on their values or attitudes, farm size and breed, but no previous study has mapped their values underlying choice of breeding goals...... these traits is longevity. Even so, dairy cows in Sweden are culled on average after only 2.4 lactations (about 4.5 years of age) i.e. before the housing and management of the heifer has paid off. Reasons for culling given in the literature include infertility, mastitis, disease or leg and claw problems...... cows. Leaving genetic concerns (b) aside we will now map factors leading to farmers culling a healthy cow even before the investment has been secured. Results show that although culling is emotionally difficult, curiosity in breeding and hope for even better heifers keep up recruitment levels and hence...

  13. [Pneumothorax during right-sided nephrectomy in a heifer].

    Science.gov (United States)

    Nuss, K; Muggli, E; Gerspach, C; Schramm, S; Dettwiler, M; Bach, F; Ringer, S

    2016-01-01

    A 250-kg heifer had signs of colic attributable to urolithiasis of the right kidney. Medical treatment did not result in resolution of clinical signs, and nephrectomy was carried out. The surgery was started with the heifer standing, and the 13th rib was resected. However, during blunt dissection of the kidney, air suddenly entered the pleural space and the heifer had acute severe dyspnoea. The hole in the pleural cavity was sutured and a chest drain was placed. Inhalation anaesthesia was then induced and nephrectomy could be completed without further complications. The heifer was discharged 11 days postoperatively, and was healthy and had been integrated into the herd 12 months after surgery. Pneumothorax must be considered a possible complication of rib resection in right-sided nephrectomy in cattle.

  14. A note on the early calving of beef heifers

    African Journals Online (AJOL)

    production in the early calving group due to reduced udder development. The results ..... adipose tissue is different to that of a lean heifer and that this storage adipose, perhaps ... Technical Services, South Africa. AMIR, S. & KALI, J.,1975.

  15. Gross margin losses due to Salmonella Dublin infection in Danish dairy cattle herds estimated by simulation modelling

    DEFF Research Database (Denmark)

    Nielsen, Torben Dahl; Kudahl, Anne Braad; Østergaard, S.

    2013-01-01

    and dynamic simulation model. The model incorporated six age groups (neonatal, pre-weaned calves, weaned calves, growing heifers, breeding heifers and cows) and five infection stages (susceptible, acutely infected, carrier, super shedder and resistant). The effects of introducing one S. Dublin infectious...... losses. This was more influential in the poorer management scenarios due to increased number of infected cows. The results can be used to inform dairy farmers of the benefits of preventing introduction and controlling spread of S. Dublin. Furthermore, they can be used in cost-benefit analyses of control...

  16. Endocrine Measurements and Calving Performance of Swedish Red and White and Swedish Holstein Dairy Cattle with Special Respect to Stillbirth

    Directory of Open Access Journals (Sweden)

    Gustafsson H

    2003-03-01

    Full Text Available During 3 consecutive calving seasons, calving performance, placental characteristics and endocrine profiles of total 98 pregnancies of late pregnant Swedish Red and White (SRB and Swedish Holstein (SLB dairy heifers and cows, were investigated. Ninety-four singleton pregnancies and 4 sets of twins were recorded. In animals with singleton pregnancy, 8 stillbirths, 7 weak calves, 3 premature parturitions and 1 abortion were registered. In the SLB heifers, 19% of stillbirth (5/26 were observed, while 5% (2/42 were noted for the SRB heifers. One stillborn calf derived from the SRB cows and none was found from the SLB cows. In the heifers and cows delivering a normal living calf with unassisted parturition, the placentome thickness monitored by ultrasonography was constant towards the end of pregnancy. The numbers of foetal cotyledons varied individually between animals but in total, fewer cotyledons were found in the foetal membranes of the SRB animals than in the SLB animals (69 ± 19 vs. (88 ± 29 (p 2α metabolite (PG-metabolite, cortisol, oestrone sulphate (E1SO4 and pregnancy associated glycoproteins (PAGs were not different by breeds and parities. In animals carrying stillbirth, higher levels of E1SO4 were found in 3 SRB animals and 1 SLB heifer, whereas lower levels of E1SO4 were recorded in 3 SLB heifers during the last week of pregnancy, compared to the profiles found in animals with unassisted parturition. Additionally, the levels of PAGs remained low and constant in 1 SRB cow (delivering a stillborn calf, 1 SRB heifer (giving birth prematurely, 4 animals (carrying twins and 1 aborting SRB cow. Our results show a very high rate of stillbirth in especially SLB heifers and deviating profiles of E1SO4 and PAGs in animals with impaired parturition were recorded.

  17. Effect of induced ruminal acidosis on blood variables in heifers

    Science.gov (United States)

    2013-01-01

    Background Ruminal acidosis is responsible for the onset of different pathologies in dairy and feedlot cattle, but there are major difficulties in the diagnosis. This study modelled the data obtained from various blood variables to identify those that could indicate the severity of ruminal acidosis. Six heifers were fed three experimental rations throughout three periods. The diets were characterised by different starch levels: high starch (HS), medium starch (MS) and low starch, as the control diet (CT). Ruminal pH values were continuously measured using wireless sensors and compared with pH measurements obtained by rumenocentesis. Blood samples were analysed for complete blood count, biochemical profile, venous blood gas, blood lipopolysaccharide (LPS) and LPS-binding proteins (LBP). Results The regression coefficient comparing the ruminal pH values, obtained using the two methods, was 0.56 (P = 0.040). Feeding the CT, MS and HS led to differences in the time spent below the 5.8, 5.5 and 5.0 pH thresholds and in several variables, including dry matter intake (7.7 vs. 6.9 vs. 5.1 kg/d; P = 0.002), ruminal nadir pH (5.69 vs. 5.47 vs. 5.44; P = 0.042), mean ruminal pH (6.50 vs. 6.34 vs. 6.31; P = 0.012), haemoglobin level (11.1 vs. 10.9 vs. 11.4 g/dL; P = 0.010), platelet count (506 vs. 481 vs. 601; P = 0.008), HCO3- (31.8 vs. 31.3 vs. 30.6 mmol/L; P = 0.071) and LBP (5.9 vs. 9.5 vs. 10.5 μg/mL; P acidosis, subacute ruminal acidosis and acute ruminal acidosis) using haemoglobin, mean platelet volume, β-hydroxybutyrate, glucose and reduced haemoglobin. Conclusions Although additional studies are necessary to confirm the reliability of these discriminant functions, the use of plasma variables in a multifactorial model appeared to be useful for the evaluation of ruminal acidosis severity. PMID:23647881

  18. Diversity of Eimeria spp. in dairy cattle of Guwahati, Assam, India

    OpenAIRE

    Das, M.; Deka, D. K.; Sarmah, P. C.; Islam, S.; S Sarma

    2015-01-01

    Aim: To determine the prevalence and diversity of Eimeria spp. in dairy cattle present in and around Guwahati, Kamrup district, Assam, India. Materials and Methods: A total of 2339 fecal samples of calves (535), heifer (641) and adult (1163) cattle were screened for 1 year present in and around Guwahati, Assam for detection of Eimeria oocysts by flotation techniques. Sporulation of the oocyst was done in 2.5% potassium dichromate solution for identification of the Eimeria species. Results: Ex...

  19. Effects of Cow Age and Pregnancy on Bartonella Infection in a Herd of Dairy Cattle

    OpenAIRE

    Maillard, R.; Grimard, B; Chastant-Maillard, S; Chomel, B.; Delcroix, T.; Gandoin, C.; Bouillin, C.; Halos, L.; Vayssier-Taussat, M.; Boulouis, H.-J.

    2006-01-01

    Bartonella spp. are small hemotropic bacteria infecting mammals. Four Bartonella species have been recently described in cattle and wild ruminants. To date, the biology and possible pathogenic role of Bartonella species isolated from ruminants are poorly understood. Therefore, a dairy herd of 448 cows and heifers was surveyed in order to establish the prevalence of Bartonella bovis and B. chomelii infections, the level of bacteremia, and the relationship between bacteremia and age or pregnanc...

  20. Economic trade-offs between genetic improvement and longevity in dairy cattle.

    Science.gov (United States)

    De Vries, A

    2017-05-01

    Genetic improvement in sires used for artificial insemination (AI) is increasing faster compared with a decade ago. The genetic merit of replacement heifers is also increasing faster and the genetic lag with older cows in the herd increases. This may trigger greater cow culling to capture this genetic improvement. On the other hand, lower culling rates are often viewed favorably because the costs and environmental effects of maintaining herd size are generally lower. Thus, there is an economic trade-off between genetic improvement and longevity in dairy cattle. The objective of this study was to investigate the principles, literature, and magnitude of these trade-offs. Data from the Council on Dairy Cattle Breeding show that the estimated breeding value of the trait productive life has increased for 50 yr but the actual time cows spend in the herd has not increased. The average annual herd cull rate remains at approximately 36% and cow longevity is approximately 59 mo. The annual increase in average estimated breeding value of the economic index lifetime net merit of Holstein sires is accelerating from $40/yr when the sire entered AI around 2002 to $171/yr for sires that entered AI around 2012. The expectation is therefore that heifers born in 2015 are approximately $50 more profitable per lactation than heifers born in 2014. Asset replacement theory shows that assets should be replaced sooner when the challenging asset is technically improved. Few studies have investigated the direct effects of genetic improvement on optimal cull rates. A 35-yr-old study found that the economically optimal cull rates were in the range of 25 to 27%, compared with the lowest possible involuntary cull rate of 20%. Only a small effect was observed of using the best surviving dams to generate the replacement heifer calves. Genetic improvement from sires had little effect on the optimal cull rate. Another study that optimized culling decisions for individual cows also showed that the

  1. Effect of high and low antral follicle count in pubertal beef heifers on IVF

    Science.gov (United States)

    Pubertal heifers can be classified between those with high (n = 25) or low (n = 15) antral follicle counts (AFC). The objective of this study was to determine oocyte development and maturation (e.g. fertility) in an IVF system for high- and low-AFC heifers. From a pool of 120 heifers, 10 high- and 1...

  2. Yeast cell wall supplementation alters the metabolic responses of crossbred heifers to an endotoxin challenge

    Science.gov (United States)

    This study examined the effect of feeding yeast cell wall (YCW) products on the metabolic responses of newly-received heifers to endotoxin challenge. Heifers (n = 24; 219 ± 2.4 kg) were separated into treatment groups receiving a Control diet (n = 8), YCW-A (2.5 grams/heifer/d; n = 8) or YCW-C (2.5 ...

  3. Performance of Pre-Weaned Dairy Calves under Hot Arid Environment: Effects of Immunoglobulins and Age on Diseases and Mortality

    Directory of Open Access Journals (Sweden)

    M. A. Razzaque

    2009-01-01

    Full Text Available Problem statement: A high mortality rate (crude mortality 43.6% of pre-weaned dairy calves resulted in unavailability of replacement heifers in Kuwait. Dairy producers resorted to import pregnant heifers for herd replacement. This study was undertaken to investigate the effects of dam vaccination and age, serum Immunoglobulin (Ig on disease syndromes and mortality in pre-weaned calves. Approach: Late pregnant Holstein Friesian dairy cows and heifers of five commercial dairy operations were divided into two herds: Treatment (T vaccinated using Lactovac against Rotavirus, Coronavirus and Escherichia coli and Control (C unvaccinated herds. Total of 1,088 newborn calves of above herds were also divided as T and C for studies from their birth to weaning at 90 days. Calves weighed at birth, fed colostrum, serum proteins and Ig (IgG, IgM and IgA were determined; disease syndromes, morbidity and mortality rates were investigated. Results: Mean birth weight (34.25±SE 0.21 kg of calves did not differ significantly (pConclusion: Inadequate levels of passive immunity of young calves were commonly found in Kuwait's farms. This study demonstrated the importance of passive immunity of calves by ensuring adequate levels of serum Ig and protein levels.

  4. Estimation of metabolic heat production and methane emission in Sahiwal and Karan Fries heifers under different feeding regimes

    Directory of Open Access Journals (Sweden)

    Sunil Kumar

    2016-05-01

    Full Text Available Aim: The objective of this study was designed to estimate the metabolic heat production and methane emission in Sahiwal and Karan Fries (Holstein-Friesian X Tharparkar heifers under two different feeding regimes, i.e., feeding regime-1 as per the National Research Council (NRC (2001 and feeding regime-2 having 15% higher energy (supplementation of molasses than NRC (2001. Materials and Methods: Six (n = 6 healthy heifers of Sahiwal and Karan Fries with 18-24 months of age were selected from Indian Council of Agricultural Research-National Dairy Research Institute, Karnal. An initial 15 days was maintained under feeding regime-1 and feeding regime-2 as adaptation period; actual experiment was conducted from 16th day onward for next 15 days. At the end of feeding regimes (on day 15th and 16th, expired air and volume were collected in Douglas bag for two consecutive days (morning [6:00 am] and evening [4:00 pm]. The fraction of methane and expired air volume were measured by methane analyzer and wet test meter, respectively. The oxygen consumption and carbon dioxide production were measured by iWorx LabScribe2. Results: The heat production (kcal/day was significantly (p0.05. The energy loss as methane (% from total heat production was significantly (p<0.05 higher in feeding regime-1. The body weight (kg, metabolic body weight (W0.75, and basal metabolic rate (kcal/kg0.75 were significantly (p<0.05 higher in feeding regime-2 in both breeds. Conclusions: This study indicates that higher energy diet by supplementing molasses may reduce energy loss as methane and enhance the growth of Sahiwal and Karan Fries heifers.

  5. Dietary melatonin alters uterine artery hemodynamics in pregnant Holstein heifers.

    Science.gov (United States)

    Brockus, K E; Hart, C G; Gilfeather, C L; Fleming, B O; Lemley, C O

    2016-04-01

    The objective was to examine uterine artery hemodynamics and maternal serum profiles in pregnant heifers supplemented with dietary melatonin (MEL) or no supplementation (CON). In addition, melatonin receptor-mediated responses in steroid metabolism were examined using a bovine endometrial epithelial culture system. Twenty singleton pregnant Holstein heifers were supplemented with 20 mg of melatonin (n = 10) or no melatonin supplementation (control; n = 10) from days 190 to 262 of gestation. Maternal measurements were recorded on days 180 (baseline), 210, 240, and 262 of gestation. Total uterine blood flow was increased by 25% in the MEL-treated heifers compared with the CON. Concentrations of progesterone were decreased in MEL vs CON heifers. Total serum antioxidant capacity was increased by 43% in MEL-treated heifers when compared with CON. Activity of cytochrome P450 1A, 2C, and superoxide dismutase was increased in bovine endometrial epithelial cells treated with melatonin, whereas the melatonin receptor antagonist, luzindole, negated the increase in cytochrome P450 2C activity. Moreover, estradiol or progesterone treatment altered bovine uterine melatonin receptor expression, which could potentiate the melatonin-mediated responses during late gestation. The observed increase in total uterine blood flow during melatonin supplementation could be related to its antioxidant properties. Compromised pregnancies are typically accompanied by increased oxidative stress; therefore, melatonin could serve as a therapeutic supplementation strategy. This could lead to further fetal programming implications in conjunction with offspring growth and development postnatally.

  6. Effect of flunixin meglumine and carprofen on pregnancy rates in dairy cattle.

    Science.gov (United States)

    von Krueger, X; Heuwieser, W

    2010-11-01

    Embryonic losses contribute considerably to low pregnancy rates. Between d 8 and 17 after breeding, the conceptus secretes interferon-τ as a mechanism for maternal recognition of pregnancy and maintenance of the corpus luteum. Nonsteroidal antiinflammatory drugs inhibit the synthesis of prostaglandin F(2α) by suppressing the enzyme cyclooxygenase. Flunixin meglumine (FM) has been demonstrated to delay luteolysis and to support embryonic survival. The objective of this study was to evaluate the effect of FM and carprofen on conception rates in dairy heifers and cows, respectively. In experiment 1, the effect of FM on pregnancy rates and progesterone concentrations in dairy heifers was tested. A total of 391 heifers were randomly assigned to 1 of 2 groups. Heifers in the treatment group (n=197) received 2.2 mg of FM i.m./kg of body weight twice on d 14/15 and 15/16 after insemination, whereas heifers in the control group (n=194) remained untreated. Blood samples from 388 heifers were taken on d 14/15 and 21/22 after artificial insemination and analyzed for progesterone. Pregnancy rates were 58.2 and 54.8% for the control and treatment groups, respectively. Mean progesterone concentrations were not affected by treatment and number of artificial insemination service (first or second artificial insemination service), but were affected by time and time × pregnancy status. In experiment 2, the objective was to verify the effects of carprofen, a longer acting nonsteroidal antiinflammatory drug and to evaluate its effect on conception rate to first service in dairy cows. A total of 380 cows were randomly assigned to 1 of 2 treatment groups. Cows in the treatment group (n=194) received 1.4 mg of carprofen s.c./kg of body weight on d 15 after insemination, whereas cows in the control group (n=186) remained untreated. Pregnancy was diagnosed between d 40 and 47 after insemination. Conception rates to first service were 35.5 and 33.0% in the control and treatment groups

  7. Cubicle Refusal in Norwegian Dairy Herds

    Directory of Open Access Journals (Sweden)

    Myren HJ

    2001-03-01

    Full Text Available In order to survey the behaviour of choosing the alley area instead of a cubicle as a lying place (cubicle refusal, a questionnaire was sent to the 273 dairy farms in Norway known to keep cows in cubicle housing systems. Sixty-six percent of the farmers contacted were included in the study. The median herd size was 18 cows (range 7–118. More than 85% of the herds had sheds providing one or more cubicles per cow. The mean herd occurrence of cubicle refusal was 6%, but showed great variation (range 0–55%. Regression analysis showed a significant association between rearing heifers in slatted floor pens and an increased cubicle refusal occurrence (p = 0.02, R2 = 0.05, while herd size, use of litter, or cubicle-to-animal ratio were not found to be associated with cubicle refusal. The practice of rearing heifers in slatted floor pens accounted for about one half of the observed cubicle refusal (etiologic fraction = 0.51.

  8. In vitro fertilization (IVF) using semi-defined culture conditions from low or high antral follicle count pubertal beef heifers

    Science.gov (United States)

    To compare the in vitro fertilization (IVF) and production (IVP) of embryos from low and high antral follicle count (AFC) heifers, AFC were determined on 106 heifers using transrectal ultrasonography. Ten heifers with the lowest AFC (avg. 13.2) and 10 heifers with the highest AFC (avg. 27.4) with ev...

  9. The Mindful Attention Awareness Scale (MAAS) in an Argentine Population

    Science.gov (United States)

    Montes, Silvana Andrea; Ledesma, Rubén Daniel; García, Natalia Mariana; Poó, Fernando Martín

    2014-01-01

    The purpose of this study was to provide evidence of validity for the Mindful Attention Awareness Scale scores in an Argentine sample (Spanish-language version). Results indicated satisfactory psychometric properties (a one-factor structure, good item discrimination, high reliability, and significant correlations with additional measures). This…

  10. The Mindful Attention Awareness Scale (MAAS) in an Argentine Population

    Science.gov (United States)

    Montes, Silvana Andrea; Ledesma, Rubén Daniel; García, Natalia Mariana; Poó, Fernando Martín

    2014-01-01

    The purpose of this study was to provide evidence of validity for the Mindful Attention Awareness Scale scores in an Argentine sample (Spanish-language version). Results indicated satisfactory psychometric properties (a one-factor structure, good item discrimination, high reliability, and significant correlations with additional measures). This…

  11. Survey of management practices related to bovine respiratory disease in preweaned calves on California dairies.

    Science.gov (United States)

    Love, W J; Lehenbauer, T W; Karle, B M; Hulbert, Lindsey E; Anderson, Randall J; Van Eenennaam, A L; Farver, T B; Aly, S S

    2016-02-01

    In the spring of 2013, a survey of California (CA) dairies was performed to characterize management practices related to bovine respiratory disease in preweaned calves, compare these practices across geographic regions of the state, and determine the principal components that explain the variability in management between herds. The questionnaire consisted of 53 questions divided into 6 sections to assess management practices affecting dairy calves from precalving to weaning. The questionnaire was mailed to 1,523 grade A licensed dairies in CA and 224 responses (14.7%) were collected. Survey response rates were similar over the 3 defined regions of CA: northern CA, northern San Joaquin Valley, and the greater southern CA region. The mean size of respondent herds was 1,423 milking cows. Most dairies reported raising preweaned calves on-site (59.7%). In 93.3% of dairies, preweaned calves were raised in some form of individual housing. Nonsaleable milk was the most frequent liquid diet fed to preweaned heifers (75.2%). Several important differences were identified between calf-raising practices in CA and practices reported in recent nationwide studies, including herd sizes, housing practices, and sources of milk fed to heifers. The differences between the CA and nationwide studies may be explained by differences in herd size. Regional differences within CA were also identified. Compared with the 2 other regions, northern CA dairies were found to have smaller herds, less Holstein cattle, calves remained with dams for longer periods of time after calving, were more likely to be certified organic dairies, and raised their own calves more often. Principal component analysis was performed and identified 11 components composed of 28 variables (questions) that explained 66.5% of the variability in the data. The identified components and questions will contribute to developing a risk assessment tool for bovine respiratory disease in preweaned dairy calves.

  12. The Argentine ant persists through unfavorable winters via a mutualism facilitated by a native tree.

    Science.gov (United States)

    Brightwell, Robert J; Silverman, Jules

    2011-10-01

    Mutualisms and facilitations can fundamentally change the relationship between an organism's realized and fundamental niche. Invasive species may prove particularly suitable models for investigating this relationship as many are dependent on finding new partners for successful establishment. We conducted field-based experiments testing whether a native tree facilitates the successful survival of the invasive Argentine ant, Linepithema humile (Mayr), through unfavorable winter conditions in the southeastern United States. We found Argentine ant nests aggregated around the native loblolly pine, Pinus taeda L., during the winter months. The bark of this tree absorbed enough radiant solar energy to reach temperatures suitable for Argentine ant foraging even when ambient temperatures should have curtailed all foraging. Conversely, foraging ceased when the trunk was shaded. The sun-warmed bark of this tree gave the Argentine ant access to a stable honeydew resource. Argentine ants were not found on or near deciduous trees even though bark temperatures were warm enough to permit Argentine ant foraging on cold winter days. Augmenting deciduous trees with sucrose water through the winter months lead to Argentine ant nests remaining at their base and Argentine ants foraging on the tree. The Argentine ant requires both foraging opportunity and a reliable winter food source to survive through unfavorable winter conditions in the southeastern United States. The loblolly pine provided both of these requirements extending the realized niche of Argentine ants beyond its fundamental niche.

  13. Glycerin levels for crossbred heifers supplemented in pasture: intake behavior

    OpenAIRE

    Farias,Mariana de Souza; Silva,Robério Rodrigues; Zawadzki,Fernando; Eiras, Carlos Emanuel; Lima,Beatriz Silva; Prado,Ivanor Nunes do

    2012-01-01

    The effect of glycerin inclusion on the intake behavior of heifers was analyzed. During the 102-day experimental period, thirty-six 13-month old heifers, average initial weight 226±12 kg, were distributed in a completely randomized design with four treatments and nine replications: G0.0 = control, G2.8 = 2.8%, G6.1 = 6.1%, and G9.1 = 9.1% glycerin in DM intake. Intake behavior was undertaken by monitoring animal activities for 24 hours every five minutes. The inclusion of glycerin in the diet...

  14. The concurrent and carry over effects of long term changes in energy intake before insemination on pregnancy per artificial insemination in heifers.

    Science.gov (United States)

    Parr, M H; Crowe, M A; Lonergan, P; Evans, A C O; Fair, T; Diskin, M G

    2015-06-01

    Follicle development in a period of negative energy balance (NEB), as experienced by the postpartum dairy cow, could be affected by undesirable metabolic changes, and may contain a developmentally incompetent oocyte with an impaired potential to establish a pregnancy. A differential feeding model in heifers was developed to evaluate the concurrent and carryover effects of reduced energy intake before insemination on pregnancy per artificial insemination (P/AI). Heifers were randomly assigned to either (i) control feed intake group (CF), n=68, 1.3 times estimated maintenance energy (M) requirements for 50 days and 2.0 M for 83 days or (ii) restricted feed intake (RF), n=88, 0.65 M for 50 days and 2.0 M for 83 days. Pregnancy per AI was determined by transrectal ultrasonography at day 30 following AI. Despite significant loss of live weight (LW; 5.8±2.1 vs 70.5±2.8 kg, respectively) and body condition score (BCS; 0.05±0.03 vs 0.45±0.03) and a significant elevation in systemic concentrations of non-esterified fatty acids in RF heifers, there was no concurrent effect on P/AI (69 vs 72%) following AI at day 50. However, there was a carryover effect on P/AI as there was an 18 percentage point difference (64 vs 82%) between CF and RF heifers following AI on day 93. The results of the study indicate that a reduction in energy intake for a 50-day period pre-insemination had no concurrent effect but had a positive carryover effect on P/AI.

  15. Heifer ovariectomy using the Willis spay instrument: Technique, morbidity and mortality.

    Science.gov (United States)

    Habermehl, N L

    1993-11-01

    Two field trials were conducted to determine the morbidity and mortality rates in heifers ovariectomized with a Willis spay instrument.Trial A used 384 Hereford and Hereford cross, auction source, heifers, weighing an average of 230 kg. In trial B, 138 auction and ranch source heifers of mixed breeding and weighing an average of 285 kg were used. All heifers were ovariectomized per vaginam, with the ovaries left in the abdomen. Prophylactic antibiotics were administered and heifers were observed at pasture for the next 150 days.The morbidity and mortality rates for heifers in trial A were 0.5% and 0.26%, respectively. In trial B, there was no morbidity or mortality.These trials indicate that the technique described is a low risk, expedient method of ovariectomizing heifers.

  16. The effects of bovine necrotic vulvo-vaginitis on reproductive and production performance of Israeli 1st calf heifers.

    Science.gov (United States)

    Goshen, T; Ben-Gera, J; Koren, O; Bdolah-Abram, T; Elad, D

    2012-04-01

    Bovine necrotic vulvovaginitis (BNVV) is a syndrome unique to Israel characterized by necrotic lesion in the caudal vagina mainly in first calf heifers after calving, associated with Porphyromonas levii. The objectives of this study were to analyze the impact of BNVV on reproductive performance, milk production and survival in the heard of first calf dairy heifers in affected farms, and to verify if the effects of BNVV are severity-dependent. For assessment of the severity level a scale of 4 degrees was formed, and cows were scored 4 to 6 d after calving. Data were obtained from two dairy farms during 2006-07, consisting of 603 lactations. The incidence and the severity of BNVV declined between 2006 and 2007, and severe BNVV tended to be more prevalent in the summer. The odds to conceive in the first artificial insemination of BNVV cow tended to be lower than healthy cows (OR = 0.676, P = 0.052). Cows with BNVV had longer empty period (145.8 d vs. 135.1 d of healthy cows, P = 0.031), but only severe BNVV had a negative effect on the odds of the cow to be empty at 150 d in milk (DIM) (OR = 2.05, P = 0.052). Severe BNVV also affected the mean survival time to conception (155.9 d vs. 142.3 d, P = 0.042). All BNVV severity degrees had a negative effect on milk production. The effect on milk production was not limited only to the beginning of the lactation, cows with BNVV produced 338.1 kg milk less than healthy cows (P = 0.016) in 305 d corrected lactation. The effect on milk production was not severity depended. No effect on survival time in the herd was demonstrated.

  17. Hsp72 is present in plasma from Holstein-Friesian dairy cattle, and the concentration level is repeatable across days and age classes

    OpenAIRE

    Nygaard Kristensen, Torsten; Løvendahl, Peter; Berg, Peer; Loeschcke, Volker

    2004-01-01

    Although heat shock proteins (Hsps) are primarily considered as being intracellular, this study identified the presence of Hsp72 in plasma from female Holstein-Friesian dairy cattle. Plasma samples were collected from the same animals at different ages and on different days after calving and accordingly divided into 5 age classes. The age classes were calves less than 235 days of age, young heifers between 235 and 305 days of age, older heifers between 305 and 560 days of age, cows early in l...

  18. An Assessment of Ammonia Emissions from Dairy Facilities in Pennsylvania

    Directory of Open Access Journals (Sweden)

    James D. Ferguson

    2001-01-01

    Full Text Available A survey of 715 Holstein dairy farms in Pennsylvania was used to construct demographics for the average Holstein dairy farm. The average Holstein dairy farm was composed of 69 lactating cows; 11 nonlactating, pregnant cows; 44 heifers; and 18 calves. Milk production averaged 27.3 kg (60.0 lb. Crop area averaged 73.6 ha. Milk production, crop area and type, average county yields, and herd animal groups were used to construct a typical feeding program for these farms. Typical rations were constructed for six feeding groups (three milk production groups, one nonlactating group, two heifer groups to meet milk production, pregnancy, and growth requirements. Rations were constructed based on three forage qualities (excellent, average, and poor typically observed on Pennsylvania dairy farms. Data for animal description (milk production, body weight, growth, and pregnancy status and ration components and amounts consumed for each animal group were input into the excretion model of the Dairy Nutrient Planner computer program (DNP. Excretion of fecal N and dry matter (DM, urinary N, and total P and K were produced for each animal group and used to assess potential volatile losses of N. Work at the Marshak Dairy, New Bolton Center, indicates the majority of urinary N is rapidly lost as ammonia from dairy facilities. Based on this observation, the losses of N as ammonia were estimated to be 4.63, 4.62, and 4.28�tonne/year for the farm with excellent, average, and poor quality forages, respectively. Volatile losses of N may be reduced most by controlling levels of urea in urine. Urinary N may be reduced through dietary manipulation of protein and carbohydrate sources. Conversion of urea to ammonia may be reduced by altering the pH of barn floors and gutters. Entrapment of ammonia may be accomplished by acidification of manure slurry. Atmospheric ammonia contributes to acid rain, eutrophication of estuaries and lakes, and particulate air pollution

  19. Creep-feeding to stimulate metabolic imprinting in nursing beef heifers: impacts on heifer growth, reproductive and physiological variables.

    Science.gov (United States)

    Reis, M M; Cooke, R F; Cappellozza, B I; Marques, R S; Guarnieri Filho, T A; Rodrigues, M C; Bradley, J S; Mueller, C J; Keisler, D H; Johnson, S E; Bohnert, D W

    2015-09-01

    This experiment compared growth, physiological, and reproductive responses of beef heifers with (MI) or without (CON) access to a creep-feeder, as a manner to stimulate metabolic imprinting while nursing their dams. On day 0, 60 Angus × Hereford heifers were ranked by BW and age (140 ± 3 kg and 68±3 days), and assigned to pairs so all ranking criteria were similar between heifers within each pair. On day 1, pairs were randomly assigned to MI (n=15) or CON (n=15). From day 1 to 51, MI pairs and their dams were allocated to 15 drylot pens where heifers had ad libitum access to a corn-based supplement through a creep-feeder. The CON pairs and their dams were maintained in an adjacent single drylot pen. From day 52 to 111, treatments were managed as a single group on a semiarid range pasture. On day 111, heifers were weaned and allocated to two pastures (one pasture/treatment), receiving hay and a corn-based concentrate until day 326. Heifer BW was recorded before and at the end of the creep-feeding period (day 1 to 51), and on days 112 and 326. On days 0, 51, 111, 187, 261, and 325, jugular blood was collected and real-time ultrasonography for longissimus muscle depth and backfat thickness assessment was performed. Blood was also collected every 10 days from days 113 to 323 for puberty evaluation via plasma progesterone. Liver and subcutaneous fat biopsies were performed on days 51, 111, 261 and 325. Average daily gain was greater (Pimprinting effect, but did not hasten their puberty attainment.

  20. Estimation of the economical effects of Eimeria infections in Estonian dairy herds using a stochastic model.

    Science.gov (United States)

    Lassen, Brian; Ostergaard, Søren

    2012-10-01

    In this study, a stochastic predictive model stimulating a constant infection pressure of Eimeria was used to estimate production outcome, economic, and effects of treatment decisions in a dairy herd of 100 cows. The intestinal parasite cause problems mainly in calves, and is known to have long term effects on the growth rate, and in severe cases can result in mortalities. Due to the inconspicuous nature of the parasite, the clinical signs and sub-clinical manifestations it may produce can be overlooked. Acquired data from literature and Estonian dairy farms were implemented in the SimHerd IV model to simulate three scenarios of symptomatic treatment: no calves treated (NT), default estimate of the current treatment strategy (DT), and all calves treated (AT). Effects of metaphylactic treatment were studied as a lowering of the infection pressure. Delay in the age for beginning of insemination of heifers was the effect with the largest economic impact on the gross margin, followed by calf mortality and reduction in growth rate. Large expenses were associated with the introduction of replacement heifers and feeding of heifers as a result of the delay in reaching a specific body weight at calving. Compared to the control scenarios, with no effects and treatments of Eimeria, dairy farmers were estimated to incur annual losses ranging 8-9% in the balanced income. Providing metaphylactic drugs resulted in an increased gross margin of 6-7%. Purchase of new heifers compensated for some production losses that would otherwise have enhanced expenses related to Eimeria. The simulation illustrates how effects of Eimeria infections can have long lasting impact on interacting management factors. It was concluded that all three simulated symptomatic treatment regimes provided only small economic benefits if they were applied alone and not in combination with lowering of infection pressure.

  1. Effect of forage level and replacing canola meal with dry distillers grains with solubles in precision-fed heifer diets: Digestibility and rumen fermentation.

    Science.gov (United States)

    Suarez-Mena, F X; Lascano, G J; Rico, D E; Heinrichs, A J

    2015-11-01

    Objectives of this study were to determine the effects of feeding differing forage-to-concentrate ratios (F:C) and inclusion rates of corn dry distillers grain with solubles (DDGS) on digestion and rumen fermentation in precision-fed dairy heifer rations. A split-plot design with F:C as whole plot and DDGS inclusion level as sub-plot was administered in a 4-period (19 d) 4 × 4 Latin square. Eight rumen-cannulated Holstein heifers (12.5 ± 0.5 mo of age and 344 ± 15 kg of body weight) housed in individual stalls were allocated to 2 F:C [50:50, low forage, or 75:25 high forage; dry matter (DM) basis] and to a sequence of DDGS inclusion (0, 7, 14, and 21%; DM basis). Forage was a mix of 50% corn silage and 50% grass hay (DM basis). Diets were fed to allow for 800 g/d of body weight gain and fed 1×/d. Rumen contents were sampled at -2, 0, 2, 4, 6, 8, 10, 12, and 20 h after feeding for rumen fermentation measures. Low-forage rations had greater DM and organic matter apparent digestibility. We detected a quadratic effect for DM, organic matter, acid detergent fiber, and neutral detergent fiber apparent digestibility, with the 14% DDGS inclusion level having the highest values. Nitrogen retention decreased with increasing levels of DDGS. Molar proportions of acetate tended to be greater for HF and decreased as DDGS increased; propionate increased as DDGS increased, resulting in the opposite effect on acetate to propionate ratio. Rumen protozoa count decreased as DDGS increased. Moderate levels (14% of DM) of DDGS appear to enhance nutrient utilization and fermentation in precision-fed dairy heifers fed different F:C diets.

  2. Fertilization and early embryonic development in heifers and lactating cows in summer and lactating and dry cows in winter.

    Science.gov (United States)

    Sartori, R; Sartor-Bergfelt, R; Mertens, S A; Guenther, J N; Parrish, J J; Wiltbank, M C

    2002-11-01

    Two experiments in two seasons evaluated fertilization rate and embryonic development in dairy cattle. Experiment 1 (summer) compared lactating Holstein cows (n = 27; 97.3 +/- 4.1 d postpartum [dppl; 40.0 +/- 1.5 kg milk/d) to nulliparous heifers (n = 28; 11 to 17 mo old). Experiment 2 (winter) compared lactating cows (n = 27; 46.4 +/- 1.6 dpp; 45.9 +/- 1.4 kg milk/d) to dry cows (n = 26). Inseminations based on estrus included combined semen from four high-fertility bulls. Embryos and oocytes recovered 5 d after ovulation were evaluated for fertilization, embryo quality (1 = excellent to 5 = degenerate), nuclei/embryo, and accessory sperm. In experiment 1, 21 embryos and 17 unfertilized oocytes (UFO) were recovered from lactating cows versus 32 embryos and no UFO from heifers (55% vs. 100% fertilization). Embryos from lactating cows had inferior quality scores (3.8 +/- 0.4 vs. 2.2 +/- 0.3), fewer nuclei/embryo (19.3 +/- 3.7 vs. 36.8 +/- 3.0) but more accessory sperm (37.3 +/- 5.8 vs. 22.4 +/- 5.5/embryo) than embryos from heifers. Sperm were attached to 80% of UFO (17.8 +/- 12.1 sperm/UFO). In experiment 2, lactating cows yielded 36 embryos and 5 UFO versus 34 embryos and 4 UFO from dry cows (87.8 vs. 89.5% fertilization). Embryo quality from lactating cows was inferior to dry cows (3.1 +/- 0.3 vs. 2.2 +/- 0.3), but embryos had similar numbers of nuclei (27.2 +/- 2.7 vs. 30.6 +/- 2.1) and accessory sperm (42.0 +/- 9.4 vs. 36.5 +/- 6.3). From 53% of the flushings from lactating cows and 28% from dry cows, only nonviable embryos were collected. Thus, embryos of lactating dairy cows were detectably inferior to embryos from nonlactating females as early as 5 d after ovulation, with a surprisingly high percentage of nonviable embryos. In addition, fertilization rate was reduced only in summer, apparently due to an effect of heat stress on the oocyte.

  3. Multiple supplements for beef heifers on pasture in dry season

    Directory of Open Access Journals (Sweden)

    Renata Pereira da Silva-Marques

    2015-02-01

    Full Text Available The objective was to evaluate levels of multiple supplement for beef heifers in restricted grazing on average daily gain (ADG, economic analysis and intakes of total dry matter (TDMI, forage dry matter (FDMI, crude protein (CPI and total digestible nutrients (TDNI. For evaluation of performance and economic analysis, twenty Nellore heifers (328.45 kg were used. The following supplements were evaluated as fed to the animals: control (mineral supplement and supplementation levels of 2, 4 and 6 kg/animal/day, composing the following percentages of average body weight (ABW: 0.55, 1.11 and 1.66%, respectively. To evaluate the nutrient intake, additional five Nellore heifers with 344 kg, were used, which were submitted to same supplements previously mentioned, in addition to the level of 2.22% of ABW (8 kg/animal/day. Average daily gain showed quadratic behavior; TDMI, CPI and TDNI had increasing linear behavior; and FDMI showed decreasing linear behavior in function of the supplementation levels. The strategy of supplying 0.55, 1.11 and 1.66% of the ABW to heifers on restricted grazing provides additional weight gains of 608, 762 and 943 g/day, respectively, which are effective in promoting similar productive and economic performance to those obtained in grazing systems in the rainy period.

  4. Effect of a single growth hormone (rbST) treatment at breeding on conception rates and pregnancy retention in dairy and beef cattle.

    Science.gov (United States)

    Starbuck, Melanie J; Inskeep, E Keith; Dailey, Robert A

    2006-07-01

    Initiation of long-term treatment with rbST (Posilac, Monsanto, St. Louis, MO) coincident with first insemination increased pregnancy rates in dairy cattle, but neither the efficacy of using only the initial injection, nor its effects on retention of pregnancy are known. Lactating dairy cows, dairy heifers, and lactating beef cows were assigned at random to treatment (rbST) or control. Dairy cows, dairy heifers, and beef cows received 500 mg rbST (n = 48, 35, 137 inseminations, respectively) at artificial insemination or were left untreated (n = 62, 33, 130 inseminations, respectively). Pregnancy was diagnosed by ultrasonography at 28-36 days. Treatment with rbST at insemination improved conception rates in dairy cows (60.4% versus 40.3%; P or =5 mm, and crown-rump lengths of embryos were not affected by treatment. The second objective was to examine the effects of rbST at insemination on birth weight and post-natal calf growth in beef cows. However, birth and weaning weights of beef calves were not affected by treatment. In conclusion, a single treatment with rbST at insemination increased conception rates in dairy cows, specifically in those >100 DIM.

  5. Intensity of Oestrus Signalling Is the Most Relevant Indicator for Animal Well-Being in High-Producing Dairy Cows

    OpenAIRE

    2011-01-01

    Full signalling of oestrous behaviour is vital for proper timing of AI and good reproductive performance, currently jeopardized by shorter observations of oestrus behaviour. Alternative indicators including progesterone (P4) recordings on-farm are tested. Oestrous intensity of 37 heifers (H) and 30 1st-parity dairy cows (C1) either Swedish Red (32) or Swedish Holstein (35) with high genetic potential for milk production, was studied in relation to AI. P4-levels in blood or milk were monitored...

  6. Performance of dairy females fed dried yeast from sugar cane

    Directory of Open Access Journals (Sweden)

    Marcia de Oliveira Franco

    2016-05-01

    Full Text Available This study was performed in order to evaluate the effect of dried yeast from sugar cane when replacing soybean meal in dairy heifers’ diets. Twenty-four heifers, with an initial body weight (BW of 178 kg, were distributed in a completely randomized design. The treatments were four levels of inclusion of dried yeast from sugar cane replacing to soybean meal (0, 33, 67 and 100% on a dry matter (DM basis. While there was no difference in DM, neutral detergent fiber (NDF, metabolizable energy or roughage intakes, the intakes of non-fiber carbohydrates and concentrate were increased. The crude protein intake decreased according to the dried yeast from sugar cane when replacing soybean meal. The digestibility coefficients of DM and NDF showed no difference. Replacement of soybean meal with dried yeast from sugar cane had no effect on performance, because average daily gain and body measurements studied were similar for all animals and inclusion levels. Soybean meal can be completely replaced with dried yeast from sugar cane in diets for growing dairy heifers without restrictions; this will not affect the intake, digestibility, physical development of animals or metabolization of protein compounds.

  7. Neospora caninum - Associated Abortions in Slovak Dairy Farm.

    Directory of Open Access Journals (Sweden)

    Silvia Špilovská

    2015-03-01

    Full Text Available Neospora caninum is considered one of the major causes of repeated abortions in livestock. This study aimed to determine the seropositivity to N. caninum using indirect ELISA and the influence of the infection on the occurrence of abortions in selected dairy herd in Slovakia.Blood samples were obtained from 490 cattle over a period of two years and were tested for N. caninum antibodies using indirect ELISA.The presence of specific antibodies in the herd was detected in 118 (24.1% cows. According to selected groups; 117 (41.0% cows with a history of abortion, 65 (43.3% heifers and 223 (2.2% cows without abortions were tested positive to Neospora. Vertical transmission of N. caninum dominated in examined herd and the relative risk (RR of dam-daughter seropositivity in progenies of seropositive mothers was 2.1 times higher than in progenies of seronegative dams. Molecular analyses of aborted foetuses of seropositive mothers showed the presence of Neospora DNA. However, 23 (28.1% of heifers born to seronegative cows were seropositive, indicating also the postnatal transmission of the infection from the environment.Study revealed significant correlation between the presence of specific antibodies and the occurrence of abortions, the risk of abortion in seropositive animals was 3.8 times higher than in seronegative ones. Incorrect farm management contributed to spread and circulation of neosporosis in entire dairy herd what could significantly impair the reproduction and economic parameters of breeding.

  8. Effects of acclimation to handling on performance, reproductive, and physiological responses of Brahman-crossbred heifers.

    Science.gov (United States)

    Cooke, R F; Arthington, J D; Austin, B R; Yelich, J V

    2009-10-01

    The objective of this study was to evaluate the effects of acclimation to handling on growth, plasma concentrations of progesterone (P4) and cortisol, temperament, and reproductive performance of Brahman-crossbred heifers. Over 2 consecutive years, 37 Braford and 43 Brahman x Angus heifers were initially evaluated, within 30 d after weaning, for BW and puberty status via transrectal ultrasonography and plasma P4 concentrations (d 0 and 10), and for temperament by measurements of chute score, pen score, and exit velocity (d 10 only). On d 11, heifers were stratified by breed, puberty status, temperament score, BW, and age and randomly assigned to receive or not (control) the acclimation treatment. Acclimated heifers were exposed to a handling process 3 times weekly (Mondays, Wednesdays, and Fridays) for 4 wk (d 11 to 39 of the experiment). The acclimation treatment was applied individually to heifers by processing them through a handling facility, whereas control heifers remained undisturbed on pasture. Heifer puberty status, evaluated via plasma P4 concentrations and transrectal ultrasonography, and BW were assessed again on d 40 and 50, d 80 and 90, and d 120 and 130. Blood samples collected before (d 10) and at the end of the acclimation period (d 40) were also analyzed for plasma concentrations of cortisol. Heifer temperament was assessed again on d 40 of the study. No interactions containing the effects of treatment, breed, and year were detected. Acclimated heifers had reduced (P Brahman-crossbred heifers.

  9. Enteric methane emissions and efficiency of use of energy in Holstein heifers and steers at age of six months.

    Science.gov (United States)

    Jiao, H P; Yan, T; McDowell, D A; Carson, A F; Ferris, C P; Easson, D L; Wills, D

    2013-01-01

    Twenty 5-mo-old Holstein cattle (10 steers and 10 heifers) were selected from a dairy herd for a 28 d study of enteric methane emissions and energy utilization. The cattle were offered a completely mixed diet with grass silage and concentrates (0.45 and 0.55, DM basis, respectively). They were housed as a single group in cubicle accommodation for the first 20 d, transferred to metabolism units for 3 d, and subsequently housed in indirect open-circuit respiration calorimeter chambers for next 5 d with measurements of feed intake, feces and urine outputs, and gaseous exchange. There were no significant differences (P>0.05) between the 2 groups in terms of animal performance (feed intake, BW, or BW gain), energy metabolism (energy intake, energy outputs, or energy use efficiency), or methane emission rates (total methane emissions expressed on feed intake or energy intake basis). Therefore, the data from the 2 groups were pooled to develop a range of relationships between inputs and outputs. The regression of energy balance or heat production against ME intake (r2=0.85; Pcattle. The methane energy output was found to be 0.068 of GE intake when the intercept was omitted from the linear equation (r2=0.73; Pcattle used for development of methane emission inventories for dairy and beef production systems. These data can add useful information, as there is little information available on measurements of maintenance energy requirement or methane emissions in young stock (6 mo old) of the current high-yielding dairy cattle. The use of these data can potentially improve the accuracy of prediction of energy requirement and methane emissions for dairy and beef production systems in these dietary conditions.

  10. Fast and flexible: argentine ants recruit from nearby trails.

    Science.gov (United States)

    Flanagan, Tatiana P; Pinter-Wollman, Noa M; Moses, Melanie E; Gordon, Deborah M

    2013-01-01

    Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.

  11. Fast and Flexible: Argentine Ants Recruit from Nearby Trails

    Science.gov (United States)

    Flanagan, Tatiana P.; Pinter-Wollman, Noa M.; Moses, Melanie E.; Gordon, Deborah M.

    2013-01-01

    Argentine ants (Linepithema humile) live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources. PMID:23967129

  12. Fast and flexible: argentine ants recruit from nearby trails.

    Directory of Open Access Journals (Sweden)

    Tatiana P Flanagan

    Full Text Available Argentine ants (Linepithema humile live in groups of nests connected by trails to each other and to stable food sources. In a field study, we investigated whether some ants recruit directly from established, persistent trails to food sources, thus accelerating food collection. Our results indicate that Argentine ants recruit nestmates to food directly from persistent trails, and that the exponential increase in the arrival rate of ants at baits is faster than would be possible if recruited ants traveled from distant nests. Once ants find a new food source, they walk back and forth between the bait and sometimes share food by trophallaxis with nestmates on the trail. Recruiting ants from nearby persistent trails creates a dynamic circuit, like those found in other distributed systems, which facilitates a quick response to changes in available resources.

  13. Effect of sugarcane silage on productive parameters of replacement Holstein-Friesian heifers

    Directory of Open Access Journals (Sweden)

    José Reyes G.

    2014-03-01

    Full Text Available Objective. Measure the productive parameters of Holstein-Friesian females from weaning to 470 days old, comparing feeding through sugarcane silage (SCS and corn silage (CS in a concentrated fodder ratio of 70:30. Materials and methods. Twenty-eight post-weaning calves were used, with an average age of 80±16 days old and an initial weight of 79.5±12.9 kg. The T-Student test was used for the comparison of means, where calves were divided into two groups of 14, one for each treatment. The body weight BW (kg, wither height WH (cm, body condition BC (1 to 5 scale, daily weight gain DWG (kg and feed conversion FC (kg was measured every 30 days. Results. Differences were found between treatments, where heifers fed with SCS showed better BC (3.12, FC (7.4 as compared to the CS treatment. No significant differences were found in terms of DWG (0.666 and 0.743 kg/d. Conclusions. Feeding based on sugarcane silage allows for an improved body condition and feed conversion of animals having with this an acceptable and cost-effective production performance in the raising of dairy replacements.

  14. Argentine Population Genetic Structure: Large Variance in Amerindian Contribution

    Science.gov (United States)

    Seldin, Michael F.; Tian, Chao; Shigeta, Russell; Scherbarth, Hugo R.; Silva, Gabriel; Belmont, John W.; Kittles, Rick; Gamron, Susana; Allevi, Alberto; Palatnik, Simon A.; Alvarellos, Alejandro; Paira, Sergio; Caprarulo, Cesar; Guillerón, Carolina; Catoggio, Luis J.; Prigione, Cristina; Berbotto, Guillermo A.; García, Mercedes A.; Perandones, Carlos E.; Pons-Estel, Bernardo A.; Alarcon-Riquelme, Marta E.

    2011-01-01

    Argentine population genetic structure was examined using a set of 78 ancestry informative markers (AIMs) to assess the contributions of European, Amerindian, and African ancestry in 94 individuals members of this population. Using the Bayesian clustering algorithm STRUCTURE, the mean European contribution was 78%, the Amerindian contribution was 19.4%, and the African contribution was 2.5%. Similar results were found using weighted least mean square method: European, 80.2%; Amerindian, 18.1%; and African, 1.7%. Consistent with previous studies the current results showed very few individuals (four of 94) with greater than 10% African admixture. Notably, when individual admixture was examined, the Amerindian and European admixture showed a very large variance and individual Amerindian contribution ranged from 1.5 to 84.5% in the 94 individual Argentine subjects. These results indicate that admixture must be considered when clinical epidemiology or case control genetic analyses are studied in this population. Moreover, the current study provides a set of informative SNPs that can be used to ascertain or control for this potentially hidden stratification. In addition, the large variance in admixture proportions in individual Argentine subjects shown by this study suggests that this population is appropriate for future admixture mapping studies. PMID:17177183

  15. Greenhouse gases inventory and carbon balance of two dairy systems obtained from two methane-estimation methods.

    Science.gov (United States)

    Cunha, C S; Lopes, N L; Veloso, C M; Jacovine, L A G; Tomich, T R; Pereira, L G R; Marcondes, M I

    2016-11-15

    The adoption of carbon inventories for dairy farms in tropical countries based on models developed from animals and diets of temperate climates is questionable. Thus, the objectives of this study were to estimate enteric methane (CH4) emissions through the SF6 tracer gas technique and through equations proposed by the Intergovernmental Panel on Climate Change (IPCC) Tier 2 and to calculate the inventory of greenhouse gas (GHG) emissions from two dairy systems. In addition, the carbon balance of these properties was estimated using enteric CH4 emissions obtained using both methodologies. In trial 1, the CH4 emissions were estimated from seven Holstein dairy cattle categories based on the SF6 tracer gas technique and on IPCC equations. The categories used in the study were prepubertal heifers (n=6); pubertal heifers (n=4); pregnant heifers (n=5); high-producing (n=6); medium-producing (n=5); low-producing (n=4) and dry cows (n=5). Enteric methane emission was higher for the category comprising prepubertal heifers when estimated by the equations proposed by the IPCC Tier 2. However, higher CH4 emissions were estimated by the SF6 technique in the categories including medium- and high-producing cows and dry cows. Pubertal heifers, pregnant heifers, and low-producing cows had equal CH4 emissions as estimated by both methods. In trial 2, two dairy farms were monitored for one year to identify all activities that contributed in any way to GHG emissions. The total emission from Farm 1 was 3.21t CO2e/animal/yr, of which 1.63t corresponded to enteric CH4. Farm 2 emitted 3.18t CO2e/animal/yr, with 1.70t of enteric CH4. IPCC estimations can underestimate CH4 emissions from some categories while overestimate others. However, considering the whole property, these discrepancies are offset and we would submit that the equations suggested by the IPCC properly estimate the total CH4 emission and carbon balance of the properties. Thus, the IPCC equations should be utilized with

  16. Residual feed intake of lactating Holstein-Friesian cows predicted from high-density genotypes and phenotyping of growing heifers.

    Science.gov (United States)

    Davis, S R; Macdonald, K A; Waghorn, G C; Spelman, R J

    2014-03-01

    A genomic prediction for residual feed intake (RFI) developed in growing dairy heifers (RFIgro) was used to predict and test breeding values for RFI in lactating cows (RFIlac) from an independent, industry population. A selection of 3,359 cows, in their third or fourth lactation during the study, of above average genetic merit for milk production, and identified as at least 15/16ths Holstein-Friesian breed, were selected for genotyping from commercial dairy herds. Genotyping was carried out using the bovine SNP50 BeadChip (Illumina Inc., San Diego, CA) on DNA extracted from ear-punch tissue. After quality control criteria were applied, genotypes were imputed to the 624,930 single nucleotide polymorphisms used in the growth study. Using these data, genomically estimated breeding values (GEBV) for RFIgro were calculated in the selected cow population based on a genomic prediction for RFIgro estimated in an independent group of growing heifers. Cows were ranked by GEBV and the top and bottom 310 identified for possible purchase. Purchased cows (n=214) were relocated to research facilities and intake and body weight (BW) measurements were undertaken in 99 "high" and 98 "low" RFIgro animals in 4 consecutive groups [beginning at d 61 ± 1.0 standard error (SE), 91 ± 0.5 SE, 145 ± 1.3 SE, and 191 ± 1.5 SE d in milk, respectively] to measure RFI during lactation (RFIlac). Each group of ~50 cows (~25 high and ~25 low RFIgro) was in a feed intake facility for 35 d, fed pasture-alfalfa cubes ad libitum, milked twice daily, and weighed every 2 to 3 d. Milk composition was determined 3 times weekly. Body weight change and BW at trial mid-point were estimated by regression of pre- and posttrial BW measurements. Residual feed intake in lactating cows was estimated from a linear model including BW, BW change, and milk component yield (as MJ/d); RFIlac differed consistently between the high and low selection classes, with the overall means for RFIlac being +0.32 and -0.31 kg of

  17. Effects of bovine somatotropin administration on growth, physiological, and reproductive responses of replacement beef heifers.

    Science.gov (United States)

    Cooke, R F; Bohnert, D W; Francisco, C L; Marques, R S; Mueller, C J; Keisler, D H

    2013-06-01

    This experiment compared growth, body composition, plasma IGF-I and leptin, and reproductive development of beef heifers receiving or not recombinant bovine ST (BST) beginning after weaning until the first breeding season. Fifty Angus × Hereford heifers (initial BW = 219 ± 2 kg; initial age = 208 ± 2 d), weaned at approximately 6 mo of age, were assigned to the experiment (d 0 to 210). On d 0, heifers were ranked by initial BW and age and assigned to 1) treatment with BST or 2) saline control. Heifers assigned to the BST treatment received subcutaneous (s.c.) injections containing 250 mg of sometribove zinc whereas control heifers received a 5-mL s.c. injection of 0.9% saline every 14 d. Treatments were initiated on d 14 and last administered on d 196. Heifers were maintained on separate pastures harvested for hay the previous summer according to treatment and received grass and alfalfa hay at a rate to provide a daily amount of 7.0 and 1.0 kg of DM per heifer, respectively. Heifer shrunk BW was collected on d 1 and 211 for heifer ADG calculation. Blood samples were collected weekly from d 0 to 210 for determination of plasma progesterone to estimate puberty attainment as well as plasma concentrations of IGF-I and leptin in selected samples. On d 0, 63, 133, and 189, heifers were evaluated for intramuscular marbling, LM depth, and backfat thickness via real-time ultrasonography. No treatment effects were detected (P = 0.27) for heifer ADG (0.49 vs. 0.51 kg/d for control and BST heifers, respectively; SEM = 0.02). Mean backfat thickness was lesser (P plasma IGF-I concentrations compared with control cohorts 7 d after treatment administration (treatment × day interaction; P plasma leptin concentrations were lesser (P = 0.05) in BST heifers compared with control cohorts (1.82 vs. 2.03 ng/mL, respectively; SEM = 0.07). Onset of puberty was hastened in BST heifers compared with control cohorts (treatment × day interaction; P = 0.04). In summary, a greater

  18. Trail Pheromone of the Argentine Ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae)

    Science.gov (United States)

    Choe, Dong-Hwan; Villafuerte, David B.; Tsutsui, Neil D.

    2012-01-01

    The Argentine ant (Linepithema humile) is recognized as one of the world's most damaging invasive species. One reason for the ecological dominance of introduced Argentine ant populations is their ability to dominate food and habitat resources through the rapid mobilization and recruitment of thousands of workers. More than 30 years ago, studies showed that (Z)-9-hexadecenal strongly attracted Argentine ant workers in a multi-choice olfactometer, suggesting that (Z)-9-hexadecenal might be the trail pheromone, or a component of a trail pheromone mixture. Since then, numerous studies have considered (Z)-9-hexadecenal as the key component of the Argentine ant trails. Here, we report the first chemical analyses of the trails laid by living Argentine ants and find that (Z)-9-hexadecenal is not present in a detectible quantity. Instead, two iridoids, dolichodial and iridomyrmecin, appear to be the primary chemical constituents of the trails. Laboratory choice tests confirmed that Argentine ants were attracted to artificial trails comprised of these two chemicals significantly more often than control trails. Although (Z)-9-hexadecenal was not detected in natural trails, supplementation of artificial dolichodial+iridomyrmecin trails with an extremely low concentraion of (Z)-9-hexadecenal did increase the efficacy of the trail-following behavior. In stark contrast with previous dogma, our study suggests that dolichodial and iridomyrmecin are major components of the Argentine ant trail pheromone. (Z)-9-hexadecenal may act in an additive manner with these iridoids, but it does not occur in detectable quantities in Argentine ant recruitment trails. PMID:23028739

  19. Deterrency and Toxicity of Essential Oils to Argentine and Red Imported Fire Ants (Hymenoptera: Formicidae)

    Science.gov (United States)

    Laboratory assays were conducted to evaluate deterrency and contact toxicity of six essential oils to the Argentine ant, Linepithema humile (Mayr), and the red imported fire ant, Solenopsis invicta Buren. In choice tests, both Argentine ants and fire ants crossed barriers treated with multiple rates...

  20. Trail pheromone of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae).

    Science.gov (United States)

    Choe, Dong-Hwan; Villafuerte, David B; Tsutsui, Neil D

    2012-01-01

    The Argentine ant (Linepithema humile) is recognized as one of the world's most damaging invasive species. One reason for the ecological dominance of introduced Argentine ant populations is their ability to dominate food and habitat resources through the rapid mobilization and recruitment of thousands of workers. More than 30 years ago, studies showed that (Z)-9-hexadecenal strongly attracted Argentine ant workers in a multi-choice olfactometer, suggesting that (Z)-9-hexadecenal might be the trail pheromone, or a component of a trail pheromone mixture. Since then, numerous studies have considered (Z)-9-hexadecenal as the key component of the Argentine ant trails. Here, we report the first chemical analyses of the trails laid by living Argentine ants and find that (Z)-9-hexadecenal is not present in a detectible quantity. Instead, two iridoids, dolichodial and iridomyrmecin, appear to be the primary chemical constituents of the trails. Laboratory choice tests confirmed that Argentine ants were attracted to artificial trails comprised of these two chemicals significantly more often than control trails. Although (Z)-9-hexadecenal was not detected in natural trails, supplementation of artificial dolichodial+iridomyrmecin trails with an extremely low concentraion of (Z)-9-hexadecenal did increase the efficacy of the trail-following behavior. In stark contrast with previous dogma, our study suggests that dolichodial and iridomyrmecin are major components of the Argentine ant trail pheromone. (Z)-9-hexadecenal may act in an additive manner with these iridoids, but it does not occur in detectable quantities in Argentine ant recruitment trails.

  1. Argentine Beef Demand and Household Choices of Retail Channels

    Directory of Open Access Journals (Sweden)

    Gustavo Rossini

    2014-07-01

    Full Text Available Household choices of outlet retail channels in beef purchases depend on several characteristics related to the quality of the product, convenience and ease of purchase, and economic factors such as price, income and payment methods. The aim of this paper is to study the influence of demographic and socio-economic attributes in the choice made by argentine consumers using a Multinominal Logit Model. The results show that the total number of purchases, the type of household, payment methods, and gender and schooling years of household head are the most relevant variables in the sample.

  2. From individual to collective dynamics in Argentine ants (Linepithema humile).

    Science.gov (United States)

    Vela-Pérez, M; Fontelos, M A; Garnier, S

    2015-04-01

    In this paper we propose a model for the formation of paths in Argentine ants when foraging in an empty arena. Based on experimental observations, we provide a distribution for the random change in direction that they approximately undergo while foraging as a mixture of a Gaussian and a Pareto distribution. By following the principles described in previous work, we consider persistence and reinforcement to create a model for the motion of ants in the plane. Numerical simulations based on this model lead to the formation of branched ant-trails analogous to those observed experimentally. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Life cycle efficiency of beef production: VIII. Relationship between residual feed intake of heifers and subsequent cow efficiency ratios.

    Science.gov (United States)

    Davis, M E; Lancaster, P A; Rutledge, J J; Cundiff, L V

    2016-11-01

    Data were collected from 1953 through 1980 from identical and fraternal twin beef and dairy females born in 1953, 1954, 1959, 1964, and 1969, and from crossbred females born as singles in 1974, and their progeny. Numbers of dams that weaned at least 1 calf and were included in the first analysis were 37, 45, and 56 in the 1964, 1969, and 1974 data sets, respectively. Respective numbers of dams that weaned 3 calves and were included in a second analysis were 6, 8, 8, 22, 33, and 33 in the 1953, 1954, 1959, 1964, 1969, and 1974 experiments. Individual feed consumption was measured at 28-d intervals from the time females were placed on the experiment until 3 calves were weaned or the dams had reached 5 yr of age. Residual feed intake (RFI) and residual gain (RG) of the heifers that subsequently became the dams in this study were determined based on ADG and DMI from 240 d of age to first calving. Various measures of cow efficiency were calculated on either a life cycle or actual lifetime basis using ratios of progeny and dam weight outputs to progeny and dam feed inputs. Residual feed intake was phenotypically independent of ADG and metabolic midweight (MMW), whereas the correlation between RFI and DMI was positive and highly significant ( = 0.67; Residual gain was highly correlated with ADG ( = 0.75; Residual feed intake was not significantly correlated with age at puberty, age at calving, or milk production. Results of this study do not indicate any serious antagonisms of postweaning heifer RFI with subsequent cow and progeny performance traits or with life cycle or actual lifetime cow efficiency. In addition, selection for increased RG would result in earlier ages at calving, but would also tend to result in taller and heavier cows.

  4. Relationship between physical characteristics and ionic content of cervical mucus pregnancy status to inseminate heifers detected in estrus

    Directory of Open Access Journals (Sweden)

    Savia CL

    2016-12-01

    Full Text Available The detection of zeal tends to be one of them factors multiple that affect the rate of pregnancy in dairy farms; because females are inseminated outside the most appropriate time to reach fertilization. The objective of the present study was to analyze macroscopic characteristics(quantity, appearance and consistency, crystallization phenomenon, pH, level of calcium, magnesium, potassium, sodium and chlorine in the cervical mucus of heifers in order to relatethese properties with the periovulatory period. Be used 20 Holstein heifers. Mucus was obtained prior to insemination and it was picked up by suction from the cervix. pH was determined using reactive tape (6-7,9 and the degree of crystallization (0-4 was evaluated according to typical and atypical fern leaf formations. It was determined pH test (6-7,9 tape and evaluate the degree of crystallization (0 - 4 according to the typical and atypical formations of fern leaves. Ionic content was determined using commercial kits (Wiener SAIC laboratories. Pregnancy was detected in 60 days post insemination. Each variable was described by its mean and deviation standard and by ANOVA established significant differences between means. It showed that the pregnancy was related to a mucus contains a concentration significantly less than K and Mg, compared with empty heifers (K, P:7,76 V: 12,97; Mg, P:2, 80 V:3,93; p<0,05 t=2,16. pH was significantly higher in the pregnant females, and the crystallization grade significantly lower (pH P:7, 60 V: 6, 23; crystallization P: 1,31 V2, 21; p<0,01 t=3,01. The results allow concluding that the optimum to inseminate was associated with cervical mucus observed macroscopically liquid, transparent and generous; with a pH above 7.0 and that it was forming atypical leaves of fern with an average of 1.31. Probably, the liquid consistency or liquid facilitates the transport of sperm and an osmotic active, responsible for the retention force is not related to content perhaps

  5. Problems Digesting Dairy Products?

    Science.gov (United States)

    ... Consumers Home For Consumers Consumer Updates Problems Digesting Dairy Products? Share Tweet Linkedin Pin it More sharing ... the natural sugar found in milk and other dairy products. People who cannot digest lactose have a ...

  6. Cost estimation of heifer mastitis in early lactation by stochastic modelling

    NARCIS (Netherlands)

    Huijps, K.; Vliegher, de S.; Lam, C.; Hogeveen, H.

    2009-01-01

    Heifer mastitis, reflected by an elevated somatic cell count (SCC) in early lactation (SCCel), results in a decreased milk production, a higher risk for subclinical and clinical mastitis during lactation, and an elevated culling hazard. The aims of this study were to calculate the costs of heifer ma

  7. 7 CFR 59.103 - Mandatory weekly reporting for steers and heifers.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Mandatory weekly reporting for steers and heifers. 59... (CONTINUED) LIVESTOCK MANDATORY REPORTING Cattle Reporting § 59.103 Mandatory weekly reporting for steers and heifers. (a) In general. The corporate officers or officially designated representatives of each steer...

  8. Endocrine profiles during attainment of puberty may predict reproductive longevity in heifers

    Science.gov (United States)

    We hypothesized that attainment of puberty through initiation and continuation of cyclic activity may be a predictor of reproductive longevity in heifers. Blood plasma was collected from 379 spring born heifers over four years from weaning to prior to breeding (October-June) in 2012-2015. Four pube...

  9. Uterine environment and pregnancy rate of heifers with elevated plasma urea nitrogen

    Science.gov (United States)

    Diets high in protein are associated with lower reproductive performance and changes in the uterine environment. The objective of this study was to determine the effect of elevated systemic concentrations of urea nitrogen on the uterine environment and pregnancy success in beef heifers. Heifers (n...

  10. Hair coat characteristics in Friesian heifers in the Netherlands and Kenya

    NARCIS (Netherlands)

    Udo, H.M.J.

    1978-01-01

    The export of about 2600 Friesian heifers to Kenya between 1971-1973 provided an opportunity of studying the adaptation problems experienced by these heifers. Within the framework of the NUFFIC (Netherlands Universities Foundation for International Cooperation) a research project entitled 'Adaptatio

  11. Camelina meal and crude glycerin as feed supplements for developing replacement beef heifers.

    Science.gov (United States)

    Moriel, P; Nayigihugu, V; Cappellozza, B I; Gonçalves, E P; Krall, J M; Foulke, T; Cammack, K M; Hess, B W

    2011-12-01

    Angus × Gelbvieh rotationally crossbred yearling heifers (n = 99, yr 1; n = 105, yr 2) were used in a 2-yr randomized complete block design experiment with repeated measures to determine the effect of feeding camelina biodiesel coproducts (meal and crude glycerin) on serum concentrations of triiodothyronine, thyroxine, insulin, β-hydroxybutyrate, and glucose, as well as on growth and reproductive performance. Heifers were assigned to 1 of 15 pens, and pens were assigned initially to receive 7.03 k·•heifer(-1)·d(-1) of bromegrass hay plus 0.95 kg·heifer(-1)·d(-1) of 1 of 3 supplements for 60 d before breeding: 1) control (50% ground corn and 50% soybean meal, as-fed basis); 2) mechanically extracted camelina meal; or 3) crude glycerin (50% soybean meal, 33% ground corn, 15% crude glycerin, 2% corn gluten meal; as-fed basis). Preprandial blood samples were collected via the jugular vein on d 0, 30, and 60 of the feeding period. A 2-injection PGF(2α) protocol (d 60 and 70 of the study) was used to synchronize estrus. Heifers were artificially inseminated 12 h after estrus was first detected. Heifers not detected in estrus within 66 h received a GnRH injection and were artificially inseminated. Dietary treatment × sampling period interactions were not detected (P = 0.17 to 0.87). Dietary treatment did not affect BW (P = 0.44 to 0.59) or serum concentrations of thyroxine (P = 0.96), β-hydroxybutyrate (P = 0.46), glucose (P = 0.59), or insulin (P = 0.44). Serum concentrations of triiodothyronine were greater (P = 0.05) in heifers fed camelina meal. Additionally, dietary treatment did not affect the percentage of heifers detected in estrus before timed AI (P = 0.83), first-service pregnancy rates of those heifers detected in estrus (P = 0.97), or overall first-service pregnancy rates (P = 0.58). Heifers fed camelina meal, however, had greater (P = 0.05) first-service pregnancy rates to timed AI than did heifers fed the control and crude glycerin supplements

  12. Effect of monensin on the estrogen-induced LH surge in prepuberal heifers.

    Science.gov (United States)

    Randel, R D; Rutter, L M; Rhodes, R D

    1982-04-01

    The effect of dietary monensin on the luteinizing hormone (LH) surge following estradiol-17 beta (E2) injection was investigated in prepuberal Simmental X Brahman-Hereford heifers. Ten heifers, weighing approximately 260 kg and approximately 10 mo of age, were equally divided by age and weight into two groups: control (C) heifers each received 1.8 kg/d of a concentrate diet plus Coastal bermudagrass hay ad libitum; monensin (M) heifers each received the same diet plus 200 mg monensin/d. All heifers were maintained in dry lots on their respective diets for 14 d before the E2 challenge. On d 15, all heifers were injected in with 5 mg of E2 in corn oil. Blood samples were collected via tail vessel puncture immediately before E2 injection and at 2-h intervals until 48 h after the E2 injection. The samples were processed for serum and stored at -20 degrees C until LH concentrations were measured by radioimmunoassay. Mean concentrations of LH in serum differed (P less than .005) between C and M heifers and with time after E2 injection. A treatment X sampling period interaction (P less than .10) indicated that maximum serum concentrations of LH (LH surge) were detected earlier (P less than .001) for M (17.2 +/- 1.8 h) than C (27.0 +/- 6.0 h) heifers after the E2 injection. When the data were arrayed relative to the time of the LH surge, treatment (P less than .05) and sampling period (P less than .001) effects were significant, but a treatment X sampling period interaction was not detected. Peak LH concentration was 23.1 +/- 3.0 ng/ml for M heifers and 21.6+/- 4.2 ng/ml for controls (P greater than .10). Duration of the LH surge was 8.0 +/- .9 h in M heifers and 4.8 +/- 1.6 h in C heifers (P less than .001). Area under the LH surge was greater (P less than .001) in M heifers than in control heifers. We conclude that dietary monensin altered the estrogen-induced LH surge in prepuberal heifers.

  13. Detección de Neospora caninum en fetos bovinos abortados espontáneamente en el nordeste argentino Neospora caninum detection in spontaneously aborted bovine fetuses from Argentine northeast

    Directory of Open Access Journals (Sweden)

    W.J. Lertora

    2010-12-01

    Full Text Available El objetivo del presente trabajo fue detectar Neospora caninum en neonatos y fetos bovinos de abortos espontáneos del nordeste argentino. Sobre un total de 26 fetos bovinos abortados espontáneamente (23 de cría y 3 de tambo se detectaron lesiones histopatológicas compatibles con neosporosis en 4 de ellos. La presencia de Neospora caninum fue confirmada mediante inmunohistoquímica en el encéfalo de 3/4 fetos (2 de cría y 1 de tambo con lesiones microscópicas compatibles con neosporosis. Las lesiones histopatológicas más relevantes fueron la asociación de encefalitis, miocarditis y hepatitis no purulenta multifocales. De 10 neonatos bovinos procesados (8 de cría y 2 de tambo, no se detectaron animales con lesiones compatibles con neosporosis. Este trabajo confirma la presencia de Neospora caninum en fetos abortados espontáneamente en bovinos de rodeos de cría y de tambo del nordeste argentino.The aim of this work was to detect the presence of Neospora caninum in bovine neonates and bovine spontaneous abortions from Argentine northeast. Histopathological lesions compatible with neosporosis were found in 4 of 26 bovine spontaneous abortions (23 beef herds and 3 dairy herds. The Neospora caninum presence was confirmed with immunohistochemical analysis in encephalic tissue in 3 of 4 fetuses (2 beef herds and 1 dairy herd that displayed microscopical lesions of neosporosis. Multifocal non-purulent encephalitis, myocarditis and hepatitis were the most relevant lesions. There were no lesions of neosporosis in 10 bovine neonates (8 beef herds and 2 dairy herds. This work confirms the presence of Neospora caninum in spontaneous bovine abortions of beef herds and dairy herds of the Argentine northeast.

  14. Genetic parameters for feed intake and feed efficiency in growing dairy heifers.

    NARCIS (Netherlands)

    Korver, S.; Eekelen, van E.A.M.; Vos, H.; Nieuwhof, G.J.; Arendonk, van J.A.M.

    1991-01-01

    Feed intake and feed efficiency are of importance in cattle breeding programmes. A divergent selection experiment on feed intake was carried out during three generations. Young performance-tested bulls were selected on high or low dry matter roughage intake. The effective phenotypic selection

  15. The First Molecular Characterization of Picocyanobacteria from the Argentine Sea

    Directory of Open Access Journals (Sweden)

    Macarena Perez-Cenci

    2014-01-01

    Full Text Available Picocyanobacteria are abundant throughout the world’s oceans. Particularly, it has been reported that Synechococcus strains have a wide latitudinal distribution, from polar to tropical waters. However, their molecular characterization in the Southwest Atlantic Ocean is still missing. We analyzed Synechococcus genetic diversity in a sector of the Argentine Sea, one of the richest biological areas of the world oceans. 16S rRNA amplicons obtained after PCR amplification of environmental DNA extracted from water samples of this area were used for DGGE and sequenced. Only Synechococcus sequences could be retrieved. On the other hand, we isolated two Synechococcus strains from the environment. Our analyses revealed that the clade I group was widespread from latitude 38°S to 48°S and that can coexist with clade IV strains in shelf waters. The cooccurrence of these two clades may be related to an adaptation to high-nutrient/low-temperature waters. Our data are the first report on Synechococcus ecotypes that would be important contributors to phytoplankton biomass in the Argentine Sea, one of the richest biological areas of the world oceans.

  16. Trail Pheromone Disruption of Argentine Ant Trail Formation and Foraging

    Science.gov (United States)

    Suckling, D.M.; Peck, R.W.; Stringer, L.D.; Snook, K.; Banko, P.C.

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2-3 m s-1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments. ?? Springer Science+Business Media, LLC 2010.

  17. Trail pheromone disruption of Argentine ant trail formation and foraging.

    Science.gov (United States)

    Suckling, David Maxwell; Peck, Robert W; Stringer, Lloyd D; Snook, Kirsten; Banko, Paul C

    2010-01-01

    Trail pheromone disruption of invasive ants is a novel tactic that builds on the development of pheromone-based pest management in other insects. Argentine ant trail pheromone, (Z)-9-hexadecenal, was formulated as a micro-encapsulated sprayable particle and applied against Argentine ant populations in 400 m2 field plots in Hawai'i Volcanoes National Park. A widely dispersed point source strategy for trail pheromone disruption was used. Traffic rates of ants in bioassays of treated filter paper, protected from rainfall and sunlight, indicated the presence of behaviorally significant quantities of pheromone being released from the formulation for up to 59 days. The proportion of plots, under trade wind conditions (2–3 m s−1), with visible trails was reduced for up to 14 days following treatment, and the number of foraging ants at randomly placed tuna-bait cards was similarly reduced. The success of these trail pheromone disruption trials in a natural ecosystem highlights the potential of this method for control of invasive ant species in this and other environments.

  18. Protein that makes sense in the Argentine ant

    Science.gov (United States)

    Ishida, Yuko; Chiang, Vicky; Leal, Walter

    2002-10-01

    With a protein-based approach, we have identified and cloned the cDNA encoding a chemosensory protein (LhumCSP) in the Argentine ant, Linepithema humile. The open reading frame of the cloned cDNA encoded a signal peptide (20 residues), and a mature protein (pI 4.62) of 106 amino acid residues. The calculated molecular mass (12,453 Da) was in agreement with the molecular mass measured by on-line chromatography-electrospray ionization mass spectrometry (12,448 Da), given the formation of two disulfide bridges. LhumCSP shared sequence similarity with various CSPs, particularly those identified and/or cloned from moth species. Also, LhumCSP showed the hallmark of the chemosensory proteins, i.e., four well conserved cysteine residues. The antennal protein was not detected in non-olfactory tissues (leg and thorax) contrary to a putative pheromone-binding protein isolated from the thorax of the red imported fire ant, Solenopsis invicta. In addition, these findings suggest that, as in Orthopterans and Phasmids, the protein that makes sense in the Argentine ant is not an odorant-binding protein, but rather a chemosensory protein.

  19. Nutrition, metabolic profiles and puberty in Brahman (Bos indicus) beef heifers.

    Science.gov (United States)

    Samadi, F; Blache, D; Martin, G B; D'Occhio, M J

    2014-05-01

    The aim of the present study was to gain an improved understanding of the relationships between body weight (BW), body condition (BCS), and metabolic homeostasis, and the attainment of puberty in Brahman heifers in a subtropical environment. Brahman heifers (200±3kg BW; 2.00±0.0 BCS) were assigned to a moderate nutrition (MN, n=11) or improved nutrition (IN, n=11) treatment from 11 to 23 months-of-age. The heifers were monitored at regular intervals for circulating concentrations of GH, IGF-1, insulin, glucose and leptin, and ovarian follicular activity was recorded until the first ovulation. From approximately 16 months of age, heifers on IN had a greater (PBrahman heifers on IN had a metabolic homeostasis that was supportive of reproductive maturation and puberty. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Effect of the administration of flunixin meglumine on pregnancy rates in Holstein heifers.

    Science.gov (United States)

    Guzeloglu, A; Erdem, H; Saribay, M K; Thatcher, W W; Tekeli, T

    2007-03-24

    Fifty-two 15-month-old Holstein heifers were synchronised with single or double injections of prostaglandin F(2alpha), followed by an injection of gonadotrophin-releasing hormone (gnrh) 48 hours later, and inseminated 12 to 14 hours after the injection of gnrh (day 0). Half of them were then injected twice intramuscularly with 1.1 mg/kg flunixin meglumine 12 hours apart, on the evening of day 15 and the morning of day 16, and the other 26 were not treated. Pregnancy was diagnosed by ultrasound 29 and 65 days after they were inseminated. On day 29, 20 of the treated heifers were pregnant compared with 13 of the control heifers (P<0.05); on day 65, 18 of the treated heifers were still pregnant compared with 12 of the control heifers (P<0.10).

  1. Ability of heifers to discriminate between familiar herdmates and members of an unfamiliar group

    DEFF Research Database (Denmark)

    Koba, Yuki; Munksgaard, Lene; Tanida, Hajime

    2009-01-01

    Using a preference test and operant conditioning in a Y-maze, this experiment examined the ability of heifers to discriminate between their own familiar herdmates and member(s) of an unfamiliar group. Sixteen Danish Friesian heifers, eight older animals (360.6 ± 24.2 days of age) and eight younger...... individual in the Y-maze. The test was repeated 12 times, with a different unfamiliar subject for each test. In experiment 2, eight heifers were individually tested in a conditioning experiment to examine whether they could learn to discriminate between a group of their three herdmates and a group of three......, heifers did not show a preference toward familiar or unfamiliar individuals; but after conditioning, some heifers could learn to discriminate between familiar and unfamiliar groups....

  2. New mutualism for old: indirect disruption and direct facilitation of seed dispersal following Argentine ant invasion.

    Science.gov (United States)

    Rowles, Alexei D; O'Dowd, Dennis J

    2009-01-01

    The indirect effects of biological invasions on native communities are poorly understood. Disruption of native ant communities following invasion by the Argentine ant (Linepithema humile) is widely reported to lead indirectly to the near complete collapse of seed dispersal services. In coastal scrub in southeastern Australia, we examined seed dispersal and handling of two native and two invasive alien plant species at Argentine ant-invaded or -uninvaded sites. The Argentine ant virtually eliminates the native keystone disperser Rhytidoponera victoriae, but seed dispersal did not collapse following invasion. Indeed, Argentine ants directly accounted for 92% of all ant-seed interactions and sustained overall seed dispersal rates. Nevertheless, dispersal quantity and quality among seed species differed between Argentine ant-invaded and -uninvaded sites. Argentine ants removed significantly fewer native Acacia retinodes seeds, but significantly more small seeds of invasive Polygala myrtifolia than did native ants at uninvaded sites. They also handled significantly more large seeds of A. sophorae, but rarely moved them >5 cm, instead recruiting en masse, consuming elaiosomes piecemeal and burying seeds in situ. In contrast, Argentine ants transported and interred P. myrtifolia seeds in their shallow nests. Experiments with artificial diaspores that varied in diaspore and elaiosome masses, but kept seed morphology and elaiosome quality constant, showed that removal by L. humile depended on the interaction of seed size and percentage elaiosome reward. Small diaspores were frequently taken, independent of high or low elaiosome reward, but large artificial diaspores with high reward instead elicited mass recruitment by Argentine ants and were rarely moved. Thus, Argentine ants appear to favour some diaspore types and reject others based largely on diaspore size and percentage reward. Such variability in response indirectly reduces native seed dispersal and can directly

  3. Comparison of two methods of breeding Holstein heifers, grazing and stabling In the villa maria farm, in firavitoba – Boyacá

    Directory of Open Access Journals (Sweden)

    Jorge Eliécer Plazas Real

    2012-06-01

    Full Text Available The breeding of replacement heifers constitutes one of the biggest challenges of competitive modern farming, especially in the dairy industry, where profitability is given a priority attention. This study compared two rearing systems for Holstein heifers on the “villa María” farm in Firavitoba (Boyacá - Colombia. This town is located in the highland tropic. For the study, 20 years old calves were randomly chosen. They were divided into two equal groups with the same food conditions and under the same study standards. This was done for a period of six months. Two methods of breeding were tested: grazing and stabling. In order to do a respective testing, the calves were weighed with an electric scale and a cattle tape measure for an interval of fifteen days. The data obtained were compared and analyzed to know which breeding method was the most effective. The results showed that the use of the stabling system produced a gain weight increase in the tested subjects, as well as maintenance of management and health conditions that were not observed in other types of rearing systems. Therefore, this system represents a better response in terms of animal wellbeing

  4. Effects of Rumen Protozoa of Brahman Heifers and Nitrate on Fermentation and In vitro Methane Production.

    Science.gov (United States)

    Nguyen, S H; Li, L; Hegarty, R S

    2016-06-01

    Two experiments were conducted assessing the effects of presence or absence of rumen protozoa and dietary nitrate addition on rumen fermentation characteristics and in vitro methane production in Brahman heifers. The first experiment assessed changes in rumen fermentation pattern and in vitro methane production post-refaunation and the second experiment investigated whether addition of nitrate to the incubation would give rise to methane mitigation additional to that contributed by defaunation. Ten Brahman heifers were progressively adapted to a diet containing 4.5% coconut oil distillate for 18 d and then all heifers were defaunated using sodium 1-(2-sulfonatooxyethoxy) dodecane (Empicol). After 15 d, the heifers were given a second dose of Empicol. Fifteen days after the second dosing, all heifers were allocated to defaunated or refaunated groups by stratified randomisation, and the experiment commenced (d 0). On d 0, an oral dose of rumen fluid collected from unrelated faunated cattle was used to inoculate 5 heifers and form a refaunated group so that the effects of re-establishment of protozoa on fermentation characteristics could be investigated. Samples of rumen fluid collected from each animal using oesophageal intubation before feeding on d 0, 7, 14, and 21 were incubated for in vitro methane production. On d 35, 2% nitrate (as NaNO3) was included in in vitro incubations to test for additivity of nitrate and absence of protozoa effects on fermentation and methane production. It was concluded that increasing protozoal numbers were associated with increased methane production in refaunated heifers 7, 14, and 21 d after refaunation. Methane production rate was significantly higher from refaunated heifers than from defaunated heifers 35 d after refaunation. Concentration and proportions of major volatile fatty acids, however, were not affected by protozoal treatments. There is scope for further reducing methane output through combining defaunation and dietary

  5. Effects of Rumen Protozoa of Brahman Heifers and Nitrate on Fermentation and Methane Production

    Directory of Open Access Journals (Sweden)

    S. H. Nguyen

    2016-06-01

    Full Text Available Two experiments were conducted assessing the effects of presence or absence of rumen protozoa and dietary nitrate addition on rumen fermentation characteristics and in vitro methane production in Brahman heifers. The first experiment assessed changes in rumen fermentation pattern and in vitro methane production post-refaunation and the second experiment investigated whether addition of nitrate to the incubation would give rise to methane mitigation additional to that contributed by defaunation. Ten Brahman heifers were progressively adapted to a diet containing 4.5% coconut oil distillate for 18 d and then all heifers were defaunated using sodium 1-(2-sulfonatooxyethoxy dodecane (Empicol. After 15 d, the heifers were given a second dose of Empicol. Fifteen days after the second dosing, all heifers were allocated to defaunated or refaunated groups by stratified randomisation, and the experiment commenced (d 0. On d 0, an oral dose of rumen fluid collected from unrelated faunated cattle was used to inoculate 5 heifers and form a refaunated group so that the effects of re-establishment of protozoa on fermentation characteristics could be investigated. Samples of rumen fluid collected from each animal using oesophageal intubation before feeding on d 0, 7, 14, and 21 were incubated for in vitro methane production. On d 35, 2% nitrate (as NaNO3 was included in in vitro incubations to test for additivity of nitrate and absence of protozoa effects on fermentation and methane production. It was concluded that increasing protozoal numbers were associated with increased methane production in refaunated heifers 7, 14, and 21 d after refaunation. Methane production rate was significantly higher from refaunated heifers than from defaunated heifers 35 d after refaunation. Concentration and proportions of major volatile fatty acids, however, were not affected by protozoal treatments. There is scope for further reducing methane output through combining

  6. Integrated tick and tick-borne disease control trials in crossbred dairy cattle in Malawi

    DEFF Research Database (Denmark)

    Tjørnehøj, Kirsten; Whiteland, A. P.; Mfitilodze, M. W.

    1996-01-01

    Crossbred dairy heifers on a farm in an East Coast fever (ECF) endemic area in Malawi were immunised against Theileria parva, Anaplasma spp., Babesia bigemina, Babesia bovis and Cowdria ruminantium. They were treated at infrequent intervals with chlorfenvinphos to limit infestation with adult ticks......, but there were no incidents of tick-borne disease in the immunised group. In a second trial, which tested a strategic dipping regimen, 107 animals were dipped 9 times over a 6 month period. Despite heavy challenge by B. bovis and moderate challenge by B. bigemina and Anaplasma spp, demonstrated serologically...

  7. Organic dairy farmers put more emphasis on production traits than conventional farmers

    DEFF Research Database (Denmark)

    Slagboom, Margot; Kargo, Morten; Edwards, David

    2016-01-01

    The overall aim of this research was to characterize the preferences of Danish dairy farmers for improvements in breeding goal traits. The specific aims were (1) to investigate the presence of heterogeneity in farmers’ preferences by means of cluster analysis, and (2) to associate these clusters......, and farmers that gave the highest ranking to cow and heifer fertility had the lowest conception rate in their herds. This finding suggests that farmers prefer to improve traits that are more problematic in their herd. The proportion of organic and conventional farmers also differed between clusters; we found...

  8. Clinical utility of calf front hoof circumference and maternal intrapelvic area in predicting dystocia in 103 late gestation Holstein-Friesian heifers and cows.

    Science.gov (United States)

    Hiew, Mark W H; Megahed, Ameer A; Townsend, Jonathan R; Singleton, Wayne L; Constable, Peter D

    2016-02-01

    The objective of this study was to determine the clinical utility of measuring calf front hoof circumference, maternal intrapelvic area, and selected morphometric values in predicting dystocia in dairy cattle. An observational study using a convenience sample of 103 late-gestation Holstein-Friesian heifers and cows was performed. Intrapelvic height and width of the dam were measured using a pelvimeter, and the intrapelvic area was calculated. Calf front hoof circumference and birth weight were also measured. Data were analyzed using Spearman's correlation coefficient (rs), Mann-Whitney U test, and binary or ordered logistic regression; P dystocia (calving difficulty score = 4 or 5), with sensitivity = 0.50 and specificity = 0.93 at the optimal cutpoint for the ratio (>0.068 cm/cm(2)). Determining the ratio of calf front hoof circumference to maternal intrapelvic area has clinical utility in predicting the calving difficulty score in Holstein-Friesian cattle.

  9. Immunological parameters and residual feed intake of Nellore heifers

    Directory of Open Access Journals (Sweden)

    Cleisy Ferreira Nascimento

    2012-12-01

    Full Text Available The residual feed intake (RFI is a parameter used in the identification of animals with respect to more efficient feed utilization. However, physiological basis are still unknown, however, the interrelationships between nutrition an immunity of the animal can contribute to the investigation of biological phenomena relevant to the RFI, since the defense system to oxidative effects caused by free radicals, is formed by acid polyunsaturated fatty acids, water soluble substances and enzymes, which derive mainly from the use of nutrients in the diet. The objective of this study was to evaluate the immunological parameters of Nellore heifers classified according to RFI. It were evaluated 176 heifers (born between 2008 and 2010, Traditional Nellore herd from Instituto de Zootecnia - Sertãozinho/SP, forming three groups of evaluation, submitted to test post weaning feed efficiency and classified into high (> mean + 0.5 SD, n= 55, medium (± 0.5 SD, n= 65 and low RFI (< mean – 0.5 SD, n= 56. The diet was formulated based on Brachiaria decumbens hay, corn, cottonseed meal and mineral mixture (45:55, forage: concentrate. The weight of the animals were performed in fasting blood samples collected by venipuncture vein, using tubes of 10 ml type vacuntainer with EDTA anticoagulant. In the clinical laboratory, we measured the values of leukocytes (LEU; Targeted (SEG and lymphocytes (LIN. The experimental design was a randomized block design using PROC GLM of SAS, considering the fixed effects of year and the age covariate in the statistical model and the averages compared by Tukey test at 5% probability. There was no significant difference (P>0,005 between variables leukocyte (LEU, SEG and LIN and class of RFI (table 1, indicating that there is no distinction between animals more efficient (low RFI and less efficient (high RFI, for inflammatory and immune responses to oxidative effects. Therefore the variables measured leukocytes not explain the differences

  10. Pregnancy rates in heifers and cows with cryopreserved sexed sperm: effects of sperm numbers per inseminate, sorting pressure and sperm storage before sorting.

    Science.gov (United States)

    Schenk, J L; Cran, D G; Everett, R W; Seidel, G E

    2009-03-15

    Field trials were conducted to increase fertility with AI of flow-sorted, sexed bovine sperm. In the first trial, a novel competitive fertilization approach was used to compare pressures (30psi vs 50psi) for sorting sperm. Both X- and Y-sperm were sorted to approximately 95% purity at 30 and at 50psi; X-50+Y-30 (and the converse) were mixed in equal numbers for AI of heifers. Fetal sex divulged which treatment produced the pregnancy; 82% of pregnancies resulted from the 30psi treatment (Ppregnancy rates in heifers relative to 50psi (42.3% vs 34.1%, n=367/group, Pdecreased pregnancy rates from 42.3% (n=367) to 36.8% (n=368; P0.1). Lactating dairy cows pre-screened for normal reproductive tracts when OvSynch injections (GnRH, prostaglandin, GnRH) were initiated, had similar (P>0.1) pregnancy rates to timed AI, with 10x10(6) sexed sperm (43.9%, n=57), 2x10(6) sexed sperm (40.5%, n=57) and 10x10(6) unsexed control sperm (55.6%, n=58). A final field trial with unselected, lactating dairy cows resulted in similar pregnancy rates for 2x10(6) sexed sperm in 0.25mL straws (25.0%, n=708) and 0.5mL straws (24.4%, n=776), but lower (P84 days in milk had the highest pregnancy rates for both sexed and unsexed sperm. These studies improved sperm sexing procedures, and provided insight into appropriate commercial use of sexed sperm.

  11. Calf form bovine leukosis with lameness in a Holstein heifer.

    Science.gov (United States)

    Tawfeeq, Mohammad Monir; Miura, Saori; Nakanishi, Yuuki; Sugimoto, Kazuya; Kobayashi, Yoshiyasu; Furuoka, Hidefumi; Inokuma, Hisashi

    2012-09-01

    A 12-month-old Holstein heifer with anorexia, lameness, and enlargement of peripheral lymph nodes was suspected of having bovine leukosis. Although lymphocytosis was not observed, cytology of fine needle aspirate from a superficial cervical node, and increased serum lactate dehydrogenase and thymidine kinase activities, strongly suggested lymphosarcoma. Increased numbers of mononuclear cells as well as mitotic cells were observed in synovial fluid collected from swollen joints. Pathological examination confirmed B-cell calf form bovine leukosis and joint swelling related to neoplastic cell infiltration. Both interleukin-2 receptor and thymidine kinase 1 genes were highly expressed in cells from superficial cervical lymph node aspirate.

  12. Stochastic dynamic simulation modeling including multitrait genetics to estimate genetic, technical, and financial consequences of dairy farm reproduction and selection strategies.

    Science.gov (United States)

    Kaniyamattam, K; Elzo, M A; Cole, J B; De Vries, A

    2016-10-01

    The objective of this study was to develop a daily stochastic dynamic dairy simulation model that included multitrait genetics and to evaluate the effects of reduced genetic models and various reproduction and selection strategies on the genetic, technical, and financial performance of a dairy herd. The 12 correlated genetic traits included in the 2014 lifetime net merit (NM$) index were modeled for each animal. For each animal, a true breeding value (TBV) for each trait was calculated as the average of the sire's and dam's TBV, plus a fraction of the inbreeding and Mendelian sampling variability. Similarly, an environmental component for each trait was calculated and was partitioned into a permanent and a daily (temporary) effect. The combined TBV and environmental effects were converted into the phenotypic performance of each animal. Hence, genetics and phenotypic performances were associated. Estimated breeding values (EBV) were also simulated. Genetic trends for each trait for the service sire were based on expected trends in US Holsteins. Surplus heifers were culled based on various ranking criteria to maintain a herd size of 1,000 milking cows. In the first 8 scenarios, culling of surplus heifers was either random or based on the EBV of NM$. Four different genetic models, depending on the presence or absence of genetic trends or genetic and environmental correlations, or both, were evaluated to measure the effect of excluding multitrait genetics on animal performance. In the last 5 scenarios, the full genetic model was used and culling of surplus heifers was either random or based on the EBV of NM$ or the EBV of milk. Sexed semen use and reliability of the EBV were also varied. Each scenario was simulated for 15yr into the future. Results showed that genetic models without all 12 genetic trends and genetic and environmental correlations provided biased estimates of the genetic, technical, and financial performance of the dairy herd. Average TBV of NM$ of all

  13. Efficiency and rumen responses in younger and older Holstein heifers limit-fed diets of differing energy density.

    Science.gov (United States)

    Zanton, G I; Heinrichs, A J

    2016-04-01

    The objective of this study was to evaluate the effects of limit feeding diets of different predicted energy density on the efficiency of utilization of feed and nitrogen and rumen responses in younger and older Holstein heifers. Eight rumen-cannulated Holstein heifers (4 heifers beginning at 257 ± 7 d, hereafter "young," and 4 heifers beginning at 610 ± 16 d, hereafter "old") were limit-fed high [HED; 2.64 Mcal/kg of dry matter (DM), 15.31% crude protein (CP)] or low (LED; 2.42 Mcal/kg of DM, 14.15% CP) energy density diets according to a 4-period, split-plot Latin square design with 28-d periods. Diets were limit-fed to provide isonitrogenous and isoenergetic intake on a rumen empty body weight (BW) basis at a level predicted to support approximately 800 g/d of average daily gain. During the last 7d of each period, rumen contents were subsampled over a 24-h period, rumen contents were completely evacuated, and total collection of feces and urine was made over 4d. Intakes of DM and water were greater for heifers fed LED, although, by design, calculated intake of metabolizable energy did not differ between age groups or diets when expressed relative to rumen empty BW. Rumen pH was lower, ammonia (NH3-N) concentration tended to be higher, and volatile fatty acids (VFA) concentration was not different for HED compared with LED and was unaffected by age group. Rumen content mass was greater for heifers fed LED and for old heifers, so when expressing rumen fermentation responses corrected for this difference in pool size, NH3-N pool size was not different between diets and total moles of VFA in the rumen were greater for heifers fed LED, whereas these pool sizes were greater for old heifers. Total-tract digestibility of potentially digestible neutral detergent fiber (NDF) was greater in heifers fed LED and for young heifers, whereas the fractional rate of ruminal passage and digestion of NDF were both greater in heifers fed LED. Digestibility of N was greater for

  14. Hábito de pastejo de novilhas em pastagens bito do gênero Brachiaria = Grazing habits of heifers on pastures of Brachiaria genus

    Directory of Open Access Journals (Sweden)

    Anderson de Moura Zanine

    2007-10-01

    Full Text Available Objetivou-se avaliar o comportamento de novilhas pastejando Brachiarias, em sistema de lotação contínua. O delineamento experimental foi o inteiramente casualizado, com duas espécies de gramíneas representando os tratamentos, cada um com cincorepetições. Foram utilizadas novilhas leiteiras, com peso vivo médio de 315 kg. O período experimental foi de 30 dias, sendo 20 para adaptação dos animais e 10 para avaliações, que consistiram de três, com duração de 24 horas cada, em intervalos de cinco dias. As novilhaspastejaram menos tempo no pasto de Brachiaria brizantha, com tempo de 10,56 horas, enquanto que o pastejo na Brachiaria decumbens foi de 11,51 horas. A quantidade de bocados por minuto foi menor para a Brachiaria decumbens, 31,27 horas, enquanto para a Brachiariabrizantha, as novilhas pastejaram com uma taxa de bocados de 37,72 bocados por minuto. As novilhas apresentam comportamento diferenciado nas gramíneas estudadas, elevando o tempo de pastejo na Brachiaria decumbens como forma de compensar um comportamento de pastejo mais seletivo.This work aimed to evaluate the grazing behavior of heifers on Brachiarias, in continuous stocking with variable stocking rates. The experimental design was completely randomized, with two pastures representing the treatments, each with five replications. Dairy heifers were used, with an average weight of 315 kg. The experiment lasted for 30 days, being 20 for adaptation of the animals and 10 for the three evaluations, each with a duration of 24 hours, in five-dayintervals. Heifers grazed less time on the pasture of Brachiaria brizantha (10.56 hours, while the grazing on Brachiaria decumbens lasted 11.51 hours. Nevertheless, there was no difference for total bites. Heifers presented different grazing on the evaluated pastures, increasing grazing time on Brachiaria decumbens to adjust for a more selective behavior.

  15. Factors affecting retention of early pregnancy in dairy cattle.

    Science.gov (United States)

    Starbuck, Melanie J; Dailey, Robert A; Inskeep, E Keith

    2004-08-01

    Potential factors affecting retention of pregnancy during weeks 5-9 of gestation were studied in dairy cows and heifers (N = 211) on two farms. Cows were examined by ultrasonography for presence of a viable embryo, and sizes of the corpus luteum (CL) and of follicles > or = 5mm were recorded. Blood samples were taken at each examination and assayed for progesterone and estradiol. Overall pregnancy loss was 11.4%. Cows with two CL did not have greater concentrations of progesterone than cows with one CL and they retained fewer pregnancies (P Embryos that were lost apparently died before CL regression. Retention of pregnancy declined in cows with high body condition and as age of the cow increased. Pregnancy retention was lower in cows bred to one of four frequently-used service sires (P body condition and service sire.

  16. Technical indicators of financial performance in the dairy herd

    DEFF Research Database (Denmark)

    Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo

    2008-01-01

    Monte Carlo simulation was used to predict the long-term financial performance related to the technical performance of dairy herds. The indicators addressed were derived from data collected routinely in the herd. They indicated technical performance that can be affected by the farmer......, mortality in cows and calves, dynamics of body condition, and somatic cell counts. Each indicator was defined by 2 or 3 levels, and 2- and 3-factor interactions were included in the simulation experiment, which included 72 scenarios. Each scenario was replicated 200 times, and the resulting gross margin per...... increased the gross margin 2.6 times more than improved reproduction efficiency, which again increased the gross margin 2.6 to 5.9 times more than improved management related to heifers, body condition score, mortality, and somatic cell counts. These results were implemented in a simple "metamodel...

  17. Activity of Bifenthrin, Chlorfenapyr, Fipronil, and Thiamethoxam against Argentine Ants (Hymenoptera: Formicidae)

    Science.gov (United States)

    Bifenthrin, chlorfenapyr, fipronil, and thiamethoxam were evaluated for activity against the Argentine ant, Linepithema humile (Mayr). Mobility impairment and lethal times were determined following topical treatments. Ants were immobilized most quickly by bifenthrin, followed by chlorfenapyr and th...

  18. Fecundity and longevity of Argentine ant (Hymenoptera: Formicidae) queens in response to irradiation

    Science.gov (United States)

    Irradiation is a postharvest quarantine treatment option to control ants and other hitchhiker pests on fresh horticultural products traded between countries. As little is known about irradiation effects on ants, radiotolerance of the Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae...

  19. Queen execution increases relatedness among workers of the invasive Argentine ant, Linepithema humile

    National Research Council Canada - National Science Library

    Inoue, Maki N; Ito, Fuminori; Goka, Koichi

    2015-01-01

    .... The Argentine ant, Linepithema humile , native to South America, forms a “supercolony” that is composed of a large number of nests and is considered to contribute to the ant's invasion success...

  20. Modelling effectiveness of herd level vaccination against Q fever in dairy cattle

    Directory of Open Access Journals (Sweden)

    Courcoul Aurélie

    2011-05-01

    Full Text Available Abstract Q fever is a worldwide zoonosis caused by the bacterium Coxiella burnetii. The control of this infection in cattle is crucial: infected ruminants can indeed encounter reproductive disorders and represent the most important source of human infection. In the field, vaccination is currently advised in infected herds but the comparative effectiveness of different vaccination protocols has never been explored: the duration of the vaccination programme and the category of animals to be vaccinated have to be determined. Our objective was to compare, by simulation, the effectiveness over 10 years of three different vaccination strategies in a recently infected dairy cattle herd. A stochastic individual-based epidemic model coupled with a model of herd demography was developed to simulate three temporal outputs (shedder prevalence, environmental bacterial load and number of abortions and to calculate the extinction rate of the infection. For all strategies, the temporal outputs were predicted to strongly decrease with time at least in the first years of vaccination. However, vaccinating only three years was predicted inadequate to stabilize these dynamic outputs at a low level. Vaccination of both cows and heifers was predicted as being slightly more effective than vaccinating heifers only. Although the simulated extinction rate of the infection was high for both scenarios, the outputs decreased slower when only heifers were vaccinated. Our findings shed new light on vaccination effectiveness related to Q fever. Moreover, the model can be further modified for simulating and assessing various Q fever control strategies such as environmental and hygienic measures.

  1. Effect of Calf Gender on Milk Yield and Fatty Acid Content in Holstein Dairy Cows

    Science.gov (United States)

    Ehrlich, James L.; Grove-White, Dai H.

    2017-01-01

    The scale of sexed semen use to avoid the birth of unwanted bull calves in the UK dairy industry depends on several economic factors. It has been suggested in other studies that calf gender may affect milk yield in Holsteins- something that would affect the economics of sexed semen use. The present study used a large milk recording data set to evaluate the effect of calf gender (both calf born and calf in utero) on both milk yield and saturated fat content. Linear regression was used to model data for first lactation and second lactation separately. Results showed that giving birth to a heifer calf conferred a 1% milk yield advantage in first lactation heifers, whilst giving birth to a bull calf conferred a 0.5% advantage in second lactation. Heifer calves were also associated with a 0.66kg reduction in saturated fatty acid content of milk in first lactation, but there was no significant difference between the genders in second lactation. No relationship was found between calf gender and milk mono- or polyunsaturated fatty acid content. The observed effects of calf gender on both yield and saturated fatty acid content was considered minor when compared to nutritional and genetic influences. PMID:28068399

  2. Embryo yield in dairy cattle after superovulation with Folltropin or Pluset.

    Science.gov (United States)

    Mikkola, M; Taponen, J

    2017-01-15

    Two commercial FSH products were compared in a retrospective study on 3990 commercial superovulations and embryo recoveries in dairy heifers and cows. In addition, the 56-day nonreturn rate of 19,400 embryos produced with these two preparations was analyzed. Embryo collections were performed during a 16-year period from donors of Holstein and Ayrshire breeds. Folltropin (Vetoquinol S.A., Lure cedex, France) group (Group F) consisted of 2592 superovulations, of which 80% were performed on heifers and 20% on cows, and Pluset (Laboratorios Calier, S.A., Barcelona, Spain) group (Group P) of 1398 treatments, of which 66% and 34% were on heifers and cows, respectively. Total number of recovered structures, number of transferable embryos, and the proportion of unfertilized ova (UFO) and degenerated embryos were analyzed. Distribution of embryos into quality grades (1-3) and developmental stages (4-9) according to the IETS classification guidelines and means for each collection were evaluated. The proportion of low-responders having fewer than five corpora lutea and yielding fewer than five embryos or ova was investigated for each treatment. Group P yielded 1.1 recovered structures more than Group F (P superovulated with Folltropin or Pluset. It was concluded that equal numbers of transferable embryos and pregnancies can be achieved with Folltropin and Pluset. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Assessment of the Applicability of Total Quality Leadership into the Argentine Army.

    Science.gov (United States)

    1995-03-01

    LEADERSHIP INTO THE ARGENTINE ARMY by Gustavo A. Landa Major, Argentine Army Engineer, Escuela Superior Tecnica , 1990 Submitted in partial fulfillment...needed to check the population reality. Different mental model [Ref 16:p. 174] may be present in the minds of the Generals. Operational definitions (see... mental model at every level. * Current promotion system does not encourage self-education. * Some possible degree of lack of confidence from senior

  4. Trail pheromone of the Argentine ant, Linepithema humile (Mayr (Hymenoptera: Formicidae.

    Directory of Open Access Journals (Sweden)

    Dong-Hwan Choe

    Full Text Available The Argentine ant (Linepithema humile is recognized as one of the world's most damaging invasive species. One reason for the ecological dominance of introduced Argentine ant populations is their ability to dominate food and habitat resources through the rapid mobilization and recruitment of thousands of workers. More than 30 years ago, studies showed that (Z-9-hexadecenal strongly attracted Argentine ant workers in a multi-choice olfactometer, suggesting that (Z-9-hexadecenal might be the trail pheromone, or a component of a trail pheromone mixture. Since then, numerous studies have considered (Z-9-hexadecenal as the key component of the Argentine ant trails. Here, we report the first chemical analyses of the trails laid by living Argentine ants and find that (Z-9-hexadecenal is not present in a detectible quantity. Instead, two iridoids, dolichodial and iridomyrmecin, appear to be the primary chemical constituents of the trails. Laboratory choice tests confirmed that Argentine ants were attracted to artificial trails comprised of these two chemicals significantly more often than control trails. Although (Z-9-hexadecenal was not detected in natural trails, supplementation of artificial dolichodial+iridomyrmecin trails with an extremely low concentraion of (Z-9-hexadecenal did increase the efficacy of the trail-following behavior. In stark contrast with previous dogma, our study suggests that dolichodial and iridomyrmecin are major components of the Argentine ant trail pheromone. (Z-9-hexadecenal may act in an additive manner with these iridoids, but it does not occur in detectable quantities in Argentine ant recruitment trails.

  5. Native supercolonies of unrelated individuals in the invasive Argentine ant

    DEFF Research Database (Denmark)

    Pedersen, Jes Søe; Krieger, Michael J. B.; Vogel, Valérie

    2006-01-01

    Kinship among group members has long been recognized as a main factor promoting the evolution of sociality and reproductive altruism, yet some ants have an extraordinary social organization, called unicoloniality, whereby individuals mix freely among physically separated nests. This type of social...... organization is not only a key attribute responsible for the ecological dominance of these ants, but also an evolutionary paradox because relatedness between nestmates is effectively zero. Recently, it has been proposed that, in the Argentine ant, unicoloniality is a derived trait that evolved after its...... introduction into new habitats. Here we test this basic assumption by conducting a detailed genetic analysis of four native and six introduced populations with five to 15 microsatellite loci and one mitochondrial gene. In contrast to the assumption that native populations consist of family-based colonies...

  6. Antibiotic sensitivity of an Argentine strain collection of Moraxella bovis.

    Science.gov (United States)

    Zielinski, G; Piscitelli, H; Perez-Monti, H; Stobbs, L A

    2000-01-01

    The antimicrobial susceptibility of 88 isolates of Moraxella bovis of Argentine origin was evaluated for 12 antimicrobials by broth microdilution procedures. The isolates had a minimum inhibitory concentration (MIC90) of or = 32 microg/mL to lincomycin. Modal MIC values for these antimicrobials were as follows: enrofloxacin, 0.03 microg/mL; ceftiofur, 0.06 pg/mL; ampicillin, 0.25 microg/mL; florfenicol, gentamicin, erythromycin, and oxytetracycline, 0.5 microg/mL; tilmicosin, 1.0 microg/mL; tylosin and spectinomycin, 4.0 microg/mL; lincomycin and erythromycin, 16 microg/mL; and trimethoprim/ sulfamethoxazole, < or = 0.25/4.75 microg/mL. These data show that all antimicrobials except lincomycin have MICs suggestive of sensitivity in vitro, though confirmation of clinical efficacy can only be properly assessed based on pharmacologic and/or clinical data to support the MIC values.

  7. Trauma and Contemporary Forms of Subjectivity: Contributions of Argentine Psychoanalysis().

    Science.gov (United States)

    Volnovich, Juan Carlos

    2017-04-01

    This paper offers arguments to justify the relevance of psychoanalysis-psychoanalyses-in present-day Argentina and reflects on the stance taken by psychoanalysts with different theoretical perspectives in the face of the havoc wreaked by state terror (1976-1983). To this end, the author focuses on the pioneers' traits, the significance of the Argentine Psychoanalytic Association in the 1950s and 1960s, and the impact of the departure of the Plataforma Group in 1971. The establishment of the latter opened the way for the development of a psychoanalysis tied to popular movements, sensitive to social conflict, and close to human rights organizations. The author explores both on psychoanalysts' intervention to address the social trauma resulting from the theft of babies during the dictatorship, and on their relationship with Grandmothers of Plaza de Mayo.

  8. Short communication: Reference limits for blood analytes in Holstein late-pregnant heifers and dry cows: Effects of parity, days relative to calving, and season.

    Science.gov (United States)

    Brscic, M; Cozzi, G; Lora, I; Stefani, A L; Contiero, B; Ravarotto, L; Gottardo, F

    2015-11-01

    Reference limits for metabolic profiles in Holstein late-pregnant heifers and dry cows were determined considering the effects of parity, days relative to calving, and season. Blood samples were collected from 104 pregnant heifers and 186 dry cows (68 primiparous and 118 pluriparous) from 60 to 10 d before the expected calving date in 31 dairy farms in northeastern Italy. Sampling was performed during summer (182 samples) and the following winter (108 samples). All the animals were judged as clinically healthy at a veterinary visit before sampling. Outliers were removed from data of each blood analyte, and variables that were not normally distributed were log transformed. A mixed model was used to test the fixed effects of parity (late-pregnant heifers, primiparous or pluriparous dry cows), class of days relative to calving (60-41 d, 40-21 d, 20-10 d), season (summer or winter), and the interactions between parity and class of days relative to calving and between parity and season, with farm as random effect. Single general reference limits and 95% confidence intervals were generated for analytes that did not vary according to fixed effects. Whenever a fixed effect included in the model significantly affected a given analyte, specific reference limits and 95% confidence intervals were generated for each of its levels. Albumin, urea, triglycerides, alanine aminotransferase, aspartate aminotransferase, creatinine kinase, conjugated bilirubin, calcium, phosphorus, magnesium, potassium, chloride, zinc, copper, and iron concentrations were not influenced by any of the fixed effects. Total protein, globulins, creatinine, glucose, alkaline phosphatase, gamma glutamyltransferase, lactate dehydrogenase, and sodium plasma concentrations were affected by parity. The class of days relative to calving had a significant effect on the concentrations of total protein, globulins, fatty acids, cholesterol, total bilirubin, and sodium. Season affected plasma concentrations of

  9. Le tournesol en Argentine : situation et défis

    Directory of Open Access Journals (Sweden)

    Devoto Rubén

    2000-05-01

    Full Text Available Quatrième culture nationale, le tournesol approche les 6 millions de tonnes de graines récoltées par an et fait de l’Argentine le premier producteur mondial. L’augmentation de sa production est accompagnée par un essor remarquable des activités de trituration, concentrées dans les sites portuaires d’exportation. Du coup, l’Argentine se hisse également au rang de premier exportateur mondial des produits dérivés : huile et tourteaux. À l’avenir, le tournesol devrait continuer à se développer. Son aptitude à supporter des sols et des climats frais et secs lui permet de s’étendre au-delà de la Pampa humide, jusqu’au sud-ouest de la province de Buenos Aires, sa zone de prédilection qu’il investit de plus en plus, au fur et à mesure de la poussée du soja dans les autres zones pampéennes. L’utilisation de graines hybrides, précoces et de meilleur rendement, pourrait être complétée par l’emploi de graines transgéniques. Mais son expansion potentielle n’interviendra qu’à la condition de relever certains défis : le développement de nouvelles variétés, l’obtention d’une meilleure qualité pour les produits dérivés et l’amélioration des moyens logistiques de commercialisation et d’exportation.

  10. Networks in Argentine agriculture: a multiple-case study approach

    Directory of Open Access Journals (Sweden)

    Sebastián Senesi

    2013-06-01

    Full Text Available Argentina is among the four largest producers of soybeans, sunflower, corn, and wheat, among other agricultural products. Institutional and policy changes during the 1990s fostered the development of Argentine agriculture and the introduction of innovative process and product technologies (no-till, agrochemicals, GMO, GPS and new investments in modern, large-scale sunflower and soybean processing plants. In addition to technological changes, a "quiet revolution" occurred in the way agricultural production was carried out and organized: from self-production or ownership agriculture to a contract-based agriculture. The objective of this paper is to explore and describe the emergence of networks in the Argentine crop production sector. The paper presents and describes four cases that currently represent about 50% of total grain and oilseed production in Argentina: "informal hybrid form", "agricultural trust fund", "investor-oriented corporate structure", and "network of networks". In all cases, hybrid forms involve a group of actors linked by common objectives, mainly to gain scale, share resources, and improve the profitability of the business. Informal contracts seem to be the most common way of organizing the agriculture process, but using short-term contracts and sequential interfirm collaboration. Networks of networks involve long-term relationships and social development, and reciprocal interfirm collaboration. Agricultural trust fund and investor-oriented corporate structures have combined interfirm collaboration and medium-term relationships. These organizational forms are highly flexible and show a great capacity to adapt to challenges; they are competitive because they enjoy aligned incentives, flexibility, and adaptability.

  11. Colony-structure variation and interspecific competitive ability in the invasive Argentine ant.

    Science.gov (United States)

    Holway, David A; Suarez, Andrew V

    2004-01-01

    The success of some invasive species may depend on phenotypic changes that occur following introduction. In Argentine ants (Linepithema humile) introduced populations typically lack intraspecific aggression, but native populations display such behavior commonly. We employ three approaches to examine how this behavioral shift might influence interspecific competitive ability. In a laboratory experiment, we reared colonies of Forelius mccooki with pairs of Argentine ant colonies that either did or did not exhibit intraspecific aggression. F. mccooki reared with intraspecifically non-aggressive pairs of Argentine ants produced fewer eggs, foraged less actively, and supported fewer living workers than those reared with intraspecifically aggressive pairs. At natural contact zones between competing colonies of L. humile and F. mccooki, the introduction of experimental Argentine ant colonies that fought with conspecific field colonies caused L. humile to abandon baits in the presence of F. mccooki, whereas the introduction of colonies that did not fight with field colonies of Argentine ants resulted in L. humile retaining possession of baits. Additional evidence for the potential importance of colony- structure variation comes from the Argentine ant's native range. At a site along the Rio de la Plata in Argentina, we found an inverse relationship between ant richness and density of L. humile (apparently a function of local differences in colony structure) in two different years of sampling.

  12. A genetic Study of Mortality in Danish Jersey Heifer Calves

    DEFF Research Database (Denmark)

    Norberg, Elise; Pryce, Jennie; Pedersen, Jørn

    2013-01-01

    . The mortality traits included in the analysis were defined as mortality in 8 different periods from 24h after birth to age 180d (d 1–14, d 15–30, d 31–60, d 61–90, d 91–120, d 121–150, and d 151–180) and mortality over the entire period. A linear model was used for estimation of genetic parameters, breeding......The aim of this study was to estimate genetic parameters for mortality of Jersey heifer calves during the first 6mo after birth, calculate the genetic trend of the trait, and estimate breeding values of widely used Jersey sires. More than 260,000 heifer calves were included in the study...... values of sires, and genetic trend. Fixed effects included in the model were herd-year class, month of birth, parity of mother, and whether the calf was sold to another farm in the first 6mo. Both direct and maternal genetic effects were included in the model; however, the maternal genetic effect...

  13. Detection of bias in animal model pedigree indices of heifers

    Directory of Open Access Journals (Sweden)

    M. LIDAUER

    2008-12-01

    Full Text Available The objective of the study was to test whether the pedigree indices (PI of heifers are biased, and if so, whether the magnitude of the bias varies in different groups of heifers. Therefore, two animal model evaluations with two different data sets were computed. Data with all the records from the national evaluation in December 1994 was used to obtain estimated breeding values (EBV for 305-days' milk yield and protein yield. In the second evaluation, the PIs were estimated for cows calving the first time in 1993 by excluding all their production records from the data. Three different statistics, a simple t-test, the linear regression of EBV on PI, and the polynomial regression of the difference in the predictions (EBV-PI on PI, were computed for three groups of first parity Ayrshire cows: daughters of proven sires, daughters of young sires, and daughters of bull dam candidates. A practically relevant bias was found only in the PIs for the daughters of young sires. On average their PIs were biased upwards by 0.20 standard deviations (78.8 kg for the milk yield and by 0.21 standard deviations (2.2 kg for the protein yield. The polynomial regression analysis showed that the magnitude of the bias in the PIs changed somewhat with the size of the PIs.;

  14. Production performance of beef cows raised on three different nutritionally controlled heifer development programs.

    Science.gov (United States)

    Freetly, H C; Ferrell, C L; Jenkins, T G

    2001-04-01

    The objective of this study was to determine primiparous heifer performance following three different heifer development strategies that were the result of timed nutrient limitation. Two hundred eighty-two spring-born MARC III heifers were weaned at 203+/-1 d of age and 205+/-1 kg BW. The experiment was conducted on two calf crops with 120 heifers born in 1996 and 162 heifers born in 1997. Treatments consisted of different quantities of the same diet being offered for a 205-d period. Heifers in the HIGH treatment were offered 263 kcal ME/(BWkg)0.75 daily. Heifers in the MEDIUM treatment were offered 238 kcal ME/(BWkg)0.75 daily. Heifers in the LOW-HIGH treatment were offered 157 kcal ME/(BWkg)0.75 daily the first 83 d and 277 kcal ME/(BWkg)0.75 daily for the remainder of the 205 d. Treatments differed in total ME intake (P calved expressed as a fraction of the cows exposed did not differ among treatments (89.7%; P = 0.83). The age of heifer at parturition (P = 0.74) and the time from first bull exposure to calving (P = 0.38) did not differ among treatments. Birth weight of calves (P = 0.80) and the calves' weaning weight (P = 0.60) did not differ among the treatments. Calf survival rate on the LOW-HIGH treatment (73%) was lower than that on the moderate treatment (89%; P = 0.007) but did not differ from that on the HIGH treatment (81%; P = 0.26). The second-calf pregnancy rate (92.8%) for cows with a nursing calf at the start of breeding did not differ between treatments (P = 0.83). These findings suggest that as long as heifers are growing and meet a minimal BW before mating, patterns of growth may be altered in the post-weaning period without a decrease in the ability of the heifer to conceive or a decrease in calf growth potential. However, limit-feeding heifers may decrease first-calf survival. These alterations in postweaning gain through monitoring the amount of feed offered can be used to optimize feed resources.

  15. A review of current timed-AI (TAI) programs for beef and dairy cattle.

    Science.gov (United States)

    Colazo, Marcos G; Mapletoft, Reuben J

    2014-08-01

    This is a review of the physiology and endocrinology of the estrous cycle and how ovarian physiology can be manipulated and controlled for timed artificial insemination (TAI) in beef and dairy cattle. Estrus detection is required for artificial insemination (AI), but it is done poorly in dairy cattle and it is difficult in beef cattle. Protocols that synchronize follicle growth, corpus luteum regression and ovulation, allowing for TAI, result in improved reproductive performance, because all animals are inseminated whether they show estrus or not. As result, TAI programs have become an integral part of reproductive management in many dairy herds and offer beef producers the opportunity to incorporate AI into their herds. Gonadotropin-releasing hormone-based protocols are commonly used in North America for estrus synchronization as part of a TAI program. Protocols that increase pregnancy rates in lactating dairy cows and suckling beef cows have been developed. Protocols that improve pregnancy rates in heifers, acyclic beef cows, and resynchronized lactating dairy cows are also discussed.

  16. Probiotic fermented dairy products

    Directory of Open Access Journals (Sweden)

    Adnan Tamime

    2003-04-01

    Full Text Available Fermented dairy products are the most popular vehicle used in theindustry for the implantation of the probiotic microflora in humans. Therefore this paper provides an overview of new knowledge on probiotic fermented dairy products. It involves historical developments, commercial probiotic microorganisms and products, and their therapeutic properties, possibilities of quality improvement of different types of newly developed fermented dairy products together with fermented goat’s milk products.

  17. Social behavior and kin discrimination in a mixed group of cloned and non cloned heifers (Bos taurus).

    Science.gov (United States)

    Coulon, M; Baudoin, C; Abdi, H; Heyman, Y; Deputte, B L

    2010-12-01

    For more than ten years, reproductive biotechnologies using somatic cell nuclear transfer have made possible the production of cloned animals in various domestic and laboratory species. The influence of the cloning process on offspring characteristics has been studied in various developmental aspects, however, it has not yet been documented in detail for behavioral traits. Behavioral studies of cloned animals have failed to show clear inter-individual differences associated with the cloning process. Preliminary results showed that clones favor each other's company. Preferential social interactions were observed among cloned heifers from the same donor in a mixed herd that also included cloned heifers and control heifers produced by artificial insemination (AI). These results suggest behavioral differences between cloned and non-cloned animals and similarities between clones from the same donor. The aim of the present study was to replicate and to extend these previous results and to study behavioral and cognitive mechanisms of this preferential grouping. We studied a group composed of five cloned heifers derived from the same donor cow, two cloned heifers derived from another donor cow, and AI heifers. Cloned heifers from the same donor were more spatially associated and interacted more between themselves than with heifers derived from another donor or with the AI individuals. This pattern indicates a possible kin discrimination in clones. To study this process, we performed an experiment (using an instrumental conditioning procedure with food reward) of visual discrimination between images of heads of familiar heifers, either related to the subjects or not. The results showed that all subjects (AI and cloned heifers) discriminated between images of familiar cloned heifers produced from the same donor and images of familiar unrelated heifers. Cattle discriminated well between images and used morphological similarities characteristic of cloned related heifers. Our

  18. Impact of supplemental protein source offered to primiparous heifers during gestation on I. Average daily gain, feed intake, calf birth body weight, and rebreeding in pregnant beef heifers.

    Science.gov (United States)

    Summers, A F; Meyer, T L; Funston, R N

    2015-04-01

    A 3-yr study was conducted to determine the effect of supplemental protein source on ADG, feed intake, calf birth BW, and subsequent pregnancy rate in pregnant beef heifers. Crossbred, Angus-based, AI-pregnant heifers (yr 1, n = 38; yr 2, n = 40; and yr 3, n = 36) were stratified by BW (450 ± 10 kg) and placed in a Calan Broadbent individual feeding system at approximately d 142 of gestation. Following a 25-d adaptation period, an 84-d feeding trial was conducted. Heifers were offered ad libitum grass hay (8 to 11% CP, DM basis) and no supplement (CON), 0.83 kg/d distillers-based supplement (HI), or 0.83 kg/d dried corn gluten-based supplement (LO). Supplements were formulated to be isocaloric, isonitrogenous (28% CP, DM basis), and equal in lipid content but differed in RUP, with HI (59% RUP) having greater levels of RUP than LO (34% RUP). Dry matter intake was also calculated based on feed NE values to account for different energy levels of the supplement compared with the control diet. Control heifers tended (P = 0.09) to consume less total DM than either supplement treatment. However, forage-only DMI was greater (P feeding period. Calf birth BW was similar (P = 0.99) among treatments. At prebreeding, CON heifers weighed less (P calf birth BW and subsequent pregnancy rates were similar.

  19. Some characteristics of primary and secondary oestrous signs in high-producing dairy cows.

    Science.gov (United States)

    Yoshida, C; Nakao, T

    2005-04-01

    Shortened and weakened oestrous signs in dairy cows may cause a failure of oestrus detection and artificial insemination timing error leading to poor reproductive performance. The aims of this study were to investigate the duration of standing oestrus in high-producing dairy cows under a free stall system, to determine the duration of expression of secondary oestrous signs before and after standing oestrus (Expt 1) and to compare the duration and intensity of oestrus between cows and heifers (Expt 2). Cattle were checked for primary and secondary oestrous signs at an interval of 4 h. Heat detection aids were also used. In Expt 1, of 56 cows which were detected in oestrus, 36 cows (64.3%) showed standing oestrus and other 20 cows (36.6%) showed secondary oestrous signs only. Duration of the standing oestrus was 6.6 +/- 6.3 h on average (+/-SD), ranging between 2 and 32 h. The cows in standing oestrus showed secondary oestrous signs during a period from 9.6 +/- 8.1 h before onset of standing to 18.4 +/- 18.8 h after the end of standing oestrus. In the cows that did not show standing oestrus, expression of secondary oestrous signs were observed for 25.7 +/- 20.5 h, which was 7.5 h shorter than the average duration of oestrus in cows showing standing oestrus. In Expt 2, nine (82%) of the 11 lactating cows in oestrus showed standing, while all the 10 heifers exhibited standing oestrus. Average duration of standing oestrus was 6.4 +/- 4.3 h in cows and 6.2 +/- 3.9 h in heifers, respectively. It may be concluded that the duration of standing oestrus is substantially shortened in lactating dairy cows, and more than one-third of cows did not show standing oestrus. In cows showing standing oestrus, duration of expression of secondary oestrous signs before and after standing is not shortened. Duration of standing oestrus in heifers was as short as that in cows.

  20. Effect of forage:concentrate ratio on digestion and reproduction in primiparous beef heifers.

    Science.gov (United States)

    Reed, B K; Hunt, C W; Sasser, R G; Momont, P A; Rode, L M; Kastelic, J P

    1997-07-01

    We evaluated the effects of high- (HF) and moderate- (MF) forage diets on digestive and reproductive characteristics in beef heifers. Thirty primiparous beef heifers were allotted by weight and backfat thickness to receive either 80:20 (HF) or 50: 50 (MF) forage:concentrate ratio diets from parturition to at least 90 d postpartum. Alfalfa hay and wheat straw were the forage sources and barley was the concentrate source. Equal daily amounts of ME were provided to all heifers by restricting intake of the MF diet. Digestibility of DM was greater (P wave dynamics and the intervals from parturition to first and second ovulation, first estrus, first service, and conception were not different between treatments. Shifts in energy supply from forage to concentrate had minimal effect on digestion and reproduction in first-calf beef heifers in this study.

  1. Whole rice bran for beef heifers raised on alexander grass pasture

    Directory of Open Access Journals (Sweden)

    P. R. Salvador

    2016-09-01

    Full Text Available The objective of this study was to evaluate the development of beef heifers exclusively fed alexander grass (Urochloa plantaginea (Link Hitch or alexander grass and whole rice meal as supplement offered from Monday to Friday. The experimental design was completely randomized, with repeated measures over time, and consisted of two treatments and three replications of area. Heifers receiving whole rice meal exhibited higher average daily gain after day 42 of pasture use and a 21% higher body weight at the end of the grazing period. The stocking rate, weight gain per area, hip height, weight-height ratio, and body condition score were similar for heifers exclusively fed alexander grass and alexander grass plus rice bran. Beef heifers raised exclusively on alexander grass from 15 to 18 months of age reached adequate body development, reproductive tract score (4.22 points and pelvic area (206.3 cm² to be bred at 18-20 months of age.

  2. Grazed grass herbage intake and performance of beef heifers with predetermined phenotypic residual feed intake classification

    National Research Council Canada - National Science Library

    Lawrence, P; Kenny, D A; Earley, B; McGee, M

    2012-01-01

    ... behaviour were measured for all heifers. Phenotypic residual feed intake (RFI) was calculated for each animal as the difference between actual DMI and expected DMI during the indoor winter period...

  3. Transmission and quantification of verocytotoxin-producing Escherichia coli O157 in dairy cattle and calves.

    Science.gov (United States)

    Schouten, J M; Graat, E A M; Frankena, K; VAN Zijderveld, F; DE Jong, M C M

    2009-01-01

    Data from a field study of 14 months duration in a naturally colonized dairy herd and data from an experiment with calves were used to quantify transmission of verocytotoxin-producing Escherichia coli (VTEC O157) in cattle. For the latter, two groups of 10 calves were randomly assigned and put out in one of two pastures. From each group, five animals were experimentally inoculated with 109 c.f.u. O157 VTEC and, considered infectious, put back in their group. Each of the susceptible contact calves became positive within 6 days of being reunited. The estimate of the basic reproduction ratio (R0) in the experiment was 7.3 (95% CI 3.92-11.5), indicating that each infectious calf will infect seven other calves on average during an assumed infectious period of 28 days in a fully susceptible population. The R0 among dairy cows appeared to be about 10 times lower (0.70, 95% CI 0.48-1.04). After the transmission experiment, six contact-infected animals that were shedding continuously during the experiment were housed in a tie stall during winter. After 40 days, all six tested negative for O157 VTEC. In June, after a period of 34 weeks in which the heifers remained negative, they were put out in a clean and isolated pasture to observe whether they started shedding again. On each pasture that was infected with O157 VTEC during the transmission experiment the previous summer, newly purchased susceptible calves were placed. None of the heifers or calves started shedding during 14 weeks, indicating that both the heifers and the previously contaminated pasture did not function as reservoir of O157 VTEC.

  4. Bovine viral diarrhea virus (BVDV) infection in dairy cattle herds in northeast Thailand.

    Science.gov (United States)

    Nilnont, Theerakul; Aiumlamai, Suneerat; Kanistanont, Kwankate; Inchaisri, Chaidate; Kampa, Jaruwan

    2016-08-01

    Bovine viral diarrhea virus causes a wide range of clinical manifestation with subsequent economic losses in dairy production worldwide. Our study of a population of dairy cattle in Thailand based on 933 bulk tank milk samples from nine public milk collection centers aimed to monitor infective status and to evaluate the effect of the infection in cows as well as to examine the reproductive performance of heifers to provide effective recommendations for disease control in Thailand. The results showed a moderate antibody-positive prevalence in the herd (62.5 %), with the proportion of class-3 herd, actively infected stage, being 17.3 %. Fourteen persistently infected (PI) animals were identified among 1196 young animals from the class-3 herds. Most of the identified PI animals, 11/14, were born in one sub-area where bovine viral diarrhea virus (BVDV) investigation has not been performed to date. With respect to reproductive performance, class-3 herds also showed higher median values of reproductive indices than those of class-0 herds. Cows and heifers in class-3 herds had higher odds ratio of calving interval (CI) and age at first service (AFS) above the median, respectively, compared to class-0 herds (OR = 1.29; P = 0.02 and OR = 1.63; P = 0.02). Our study showed that PI animals were still in the area that was previously studied. Furthermore, a newly studied area had a high prevalence of BVDV infection and the infection affected the reproductive performance of cows and heifers. Although 37.5 % of the population was free of BVDV, the lack of official disease prevention and less awareness of herd biosecurity may have resulted in continuing viral spread and silent economic losses have potentially occurred due to BVDV. We found that BVDV is still circulating in the region and, hence, a national control program is required.

  5. Economic analysis of reproductive management strategies on US commercial dairy farms.

    Science.gov (United States)

    Olynk, N J; Wolf, C A

    2008-10-01

    Reproductive management has received increased attention in recent years as new technologies and programs have been developed to aid dairy managers in efficiently breeding cows and heifers. Efficient breeding of cows and heifers has become increasingly difficult as fertility has decreased because of a correlated negative response with milk yield. Dairy farm survey results were used to parameterize the economic analyses of reproductive management programs. Reproductive management program costs and the levels of reproductive performance achieved with such programs varied significantly among farms and were especially sensitive to on-farm labor costs. For example, visual heat detection requires more hours of labor per cow than use of an estrus synchronization program. Therefore, visual heat detection programs were relatively more sensitive to labor costs than synchronization programs. In addition, past reproductive performance was found to affect the determination of which reproductive program was optimal. Farms that had attained high levels of labor efficiency for visual heat detection in the past had less incentive to adopt a synchronization program than farms with less efficient visual heat detection.

  6. Risk Factors Influencing Conception Rate in Holstein Heifers before Artificial Insemination or Embryo Transfer

    OpenAIRE

    2016-01-01

    The objective of this study was to show the risk factors affecting the conception rate in Holstein heifers after synchronization of estrus. A total of 275 Holstein heifers housed in a free barn were used for the experiment. The herd was visited regularly at four week intervals for synchronization of estrus using Heatsynch and CIDR-Heatsynch protocols. A group of four to 14 animals, depending on the availability, were referred to the experiment at each visit. Estrus induction rates in the two ...

  7. Effect of progesterone supplementation in the first week post conception on embryo survival in beef heifers

    OpenAIRE

    2009-01-01

    Progesterone is essential for establishment and maintenance of pregnancy in mammals. The objective of this study was to examine the effect of elevating progesterone during the different physiological stages of early embryo development on embryo survival. Estrus was synchronized in cross-bred beef heifers (n = 197, ∼2-years old) and they were inseminated 12–18 h after estrus onset (=Day 0). Inseminated heifers were randomly assigned to 1 of 3 treatments: (1) Control, n = 69; (2) progesterone s...

  8. Efficacy of actaplanin fed on a twice-weekly basis to grazing stocker heifers.

    Science.gov (United States)

    Chase, C C; Randel, R D; Carroll, L H

    1987-02-01

    Brahman (16), Brangus (32) and Simmental X Brahman (16) open heifers were assigned to four treatment levels and two body weight categories. The weight categories were light (250 kg) and heavy (306 kg). Treatment groups were 0, 600, 900 and 1,200 mg actaplanin.head-1.feeding-1 with feeding only on Monday and Friday. Heifers were group-fed .91 kg/head of supplement (95% soybean meal: 5% molasses) containing actaplanin. Heifers grazed eight Coastal bermudagrass pastures throughout the experiment (July 29 to November 15, 1982). After 75 d on experiment, an additional 1.36 kg of a commercial 14% crude protein supplement was fed on the days that actaplanin was not fed. All heifers were weighted and rotated among pastures at 14-d intervals (last weight period was 11 d) as an attempt to equalize forage availability among groups. Over the entire experiment (109 d), light-weight heifers that were fed actaplanin responded (P less than .01) with greater average daily gain (ADG; .37, .35, .21 kg/d; 600, 900, 1,200) compared with controls (0 mg; .18 kg/d). A trend in response (P less than .10) to actaplanin feeding occurred for heavy-weight heifers (.23, .38, .34 kg/d; 600, 900, 1,200 mg vs controls (.22 kg/d). For light-weight heifers, ADG decreased lineraly (P less than .01) as actaplanin increased from 600 to 1,200 mg, while ADG for heavy-weight heifers increased linearly (P less than .10).(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Pathogen-specific incidence rate of clinical mastitis in Flemish dairy herds, severity, and association with herd hygiene.

    Science.gov (United States)

    Verbeke, Joren; Piepers, Sofie; Supré, Karlien; De Vliegher, Sarne

    2014-11-01

    A one-year survey on clinical mastitis was conducted on 50 randomly selected commercial Flemish dairy herds to estimate the pathogen-specific incidence rate of clinical mastitis (IRCM). The severity of the cases and the potential associations with herd hygiene were studied. Participating producers sampled 845 cases and 692 dairy cows. The mean and median IRCM was estimated at 7.4 and 5.3 quarter cases per 10,000 cow-days at risk, respectively. A large between-herd variation was observed (range of 0-21.3). In general, the IRCM was lower in heifers compared with multiparous cows (2.9 vs. 11.0 quarter cases per 10,000 cow-days at risk). However, the overall IRCM in the first week after calving was higher in heifers compared with cows (43.4 vs. 31.6 quarter cases per 10,000 cow-days at risk). Streptococcus uberis (18.2% of the cases) and Escherichia coli (15.5%) were the most frequently isolated pathogens and no growth was observed in 19.9% of the cases. The majority of the cases (63.1%) were mild (only clots in milk). Moderate (hard quarter without general signs) and severe symptoms (systemic illness) were observed in 29.9 and 7.0% of the cases, respectively. Isolation of E. coli (vs. any other culture result) was more likely in moderate and severe cases compared with mild cases. Overall IRCM and E. coli IRCM were higher in dirty compared with clean herds based on udder hygiene scores (9.0 and 1.7 vs. 6.0 and 0.6 quarter cases per 10,000 cow-days at risk, respectively). This study broadens the knowledge on clinical mastitis in Flemish dairy herds and underlines the high risk of CM in early-lactation heifers, the role of the so-called environmental pathogens, and herd hygiene.

  10. Association of herd BRSV and BHV-1 seroprevalence with respiratory disease and reproductive performance in adult dairy cattle

    Directory of Open Access Journals (Sweden)

    Raaperi Kerli

    2012-01-01

    Full Text Available Abstract Background The aim of this study was to detect the associations between bovine herpesvirus 1 (BHV-1 status of a herd and respiratory disease (BRD occurrence and reproductive performance in pregnant heifers and cows. The association between management-related factors and higher BRD occurrence was also estimated. Methods Serum samples, collected from cows and youngstock from 103 dairy cattle herds, were analyzed for antibodies against BHV-1, bovine respiratory syncytial virus (BRSV, bovine viral diarrhoea virus (BVDV, and Mycoplasma bovis. A questionnaire was used to collect data concerning herd management factors and reproductive performance, as well as the occurrence of clinical signs of respiratory disease in the last two years, as evaluated by the veterinarian or farm manager. Multiple correspondence analysis (MCA and logistic regression analysis were performed to identify and quantify the risk factors. Results A low to moderate prevalence (1-49% of BRSV antibodies among youngstock was associated with a high occurrence of respiratory disease (OR = 6.2, p = 0.010 in cows and in-calf heifers. Employees of the farm may participate in the spread of such disease. Larger herd size, loose-housing of cows, housing youngstock separately from cows until pregnancy, and purchasing new animals were factors possibly related to a high occurrence of respiratory disease symptoms in pregnant heifers and cows. The highest risk of abortions (> 1.3% and increased insemination index (number of inseminations per pregnancy (> 1.9 occurred in herds with a moderate prevalence of BHV-1 antibodies (1-49% in cows. Conclusions BHV-1 was not associated with acute respiratory disease in adult dairy cattle, however was significantly related to reproductive performance. BRSV possesses the main role in respiratory disease complex in adult dairy cattle.

  11. Effect of feed intake restriction on reproductive performance and pregnancy rate in Egyptian buffalo heifers.

    Science.gov (United States)

    Hussein, Hassan Ali; Abdel-Raheem, Sherief Mohamed

    2013-04-01

    The objective of the present experiment is to study the effect of feed intake restriction on the reproductive performance and pregnancy rate in Egyptian buffalo heifers. Thirty anestrus buffalo heifers were randomly divided into two equal groups. The low feed intake (LFI, n=15, 50 % restriction) group was fed a diet that consists of 3 kg concentrate, 1 kg wheat straw, and 3 kg fresh alfalfa, while the high feed intake (HFI, n=15) group was fed double the amount given to the LFI group for 4 months. All animals were weighed, transrectally examined, and visually checked for the signs of estrus, and blood samples were collected. Heifers in heat were mated with one fertile bull. The number of heifers showing estrus activity was 93.3 % in HFI vs. 20 % in LFI (Prate, and overall mean of progesterone and estrogen concentrations were significantly higher (Pglucose, total cholesterol, and calcium were significantly higher (Pfeed intake to 50 % from NRC recommendations impair reproductive performance in terms of increasing the age at first service and reducing the pregnancy rate in buffalo heifers. In conclusion, feed intake could be effective in improvement of reproductive performance in buffalo heifers and further studies should be done on large scale of buffaloes in this point.

  12. Effect of meloxicam on pregnancy rate of recipient heifers following transfer of in vitro produced embryos.

    Science.gov (United States)

    Aguiar, T S; Araújo, C V; Tirloni, R R; Martins, L R

    2013-12-01

    The main objective of this study was to determine if administration of meloxicam, a cyclooxygenase (COX) two inhibitor, to heifers in which embryo transfer (ET) is more difficult and requires a greater manipulation of the tract, would be beneficial. Nulliparous recipient heifers were divided in two groups: CON (n = 102), in which animals received 10 ml of saline IM (the same volume of meloxicam) and MEL (n = 105) animals that were treated with meloxicam. According to the degree in passing the catheter, recipients from both groups were classified as Grade I, easy (meloxicam (10 ml).There was no difference in the pregnancy rates on Day 35 considering animals which presented Grade I cervix independently whether the treatment was performed or not (p = 0.22). There was a statistical difference in the pregnancy rates (p meloxicam had a positive influence on general pregnancy rate of treated heifers in comparison to non-treated heifers. It was also observed that pregnancy rate was not influenced by meloxicam administration in Grade I heifers. Treatment increased the pregnancy rate of Grade II heifers.

  13. Herpetiform genital lesions in a heifer with mucosal disease.

    Science.gov (United States)

    Fabis, J J; Szkudlarek, L; Risatti, G R; Sura, R; Garmendia, A E; Van Kruiningen, H J

    2008-03-01

    A 14-month-old heifer with a 17-day history of unresponsive bloody diarrhea was necropsied. There were focal, pink-red erosions of the nares and hard palate; ulcers and fissures of the tongue; and multiple ulcerative lesions of the alimentary canal. Interdigital skin of both rear limbs was ulcerated and bleeding; and the margins of the vulva contained punctiform red ulcers. The gross lesions were consistent with mucosal disease. Histopathology and laboratory testing ruled out rinderpest, foot-and-mouth disease, and vesicular stomatitis, and identified bovine virus diarrhea virus to be the cause of this disease. Lesions of the vulva similar to those seen in some stages of infectious pustular vulvovaginitis were negative for bovine herpesvirus-1 and tested positive for bovine viral diarrhea virus antigen by immunohistochemistry.

  14. Factors Affecting SSR in Holstein Dairy Cows

    Directory of Open Access Journals (Sweden)

    Alireza Heravi Mosavi

    2016-08-01

    Full Text Available Introduction Secondary sex ratio (SSR is the proportion of males to females at birth. It has been shown in many different mammalian species, many factors are associated with SSR. Changes in secondary sex ratio in dairy cows is considered economically important and the ability to change it could affect the revenues and profitability of a dairy farm. Thus, sperm or embryo sexing techniques in recent years has attracted more attention. Most breed of dairy cattle are more likely to have female calf is born to use them as replacement heifers and in order to maintain their productive herd number. On the contrary, when the goal is the production of meat, bull calves due to higher growth rates and production efficiency, are more convenient and more economically efficient. The aim of present study was to investigate some key factors affecting SSR in Iranian Holstein cows. According to Fisher, the sex ratio in the population under the control of natural selection is not always the same. There is overwhelming evidence to support the theory that shows Fisher Primary and secondary sex ratio sex ratio can deviate from this balance and natural selection caused a change in this ratio can be in certain circumstances. For example, the secondary sex ratio of 52:48 has been reported in dairy cows. Studies on mammalian species suggest that several factors, including latitude of the location, the dominant regional climate model, time and frequency of mating to ovulation, diet, age of parents, physical score, breed and produced eggs from ovarian left or right can have a significant effect on the secondary sex ratio. Weather conditions may modify the internal environment and the effect on physiological mechanisms or through the impact on the frequency and type of foods available to parents, the secondary sex ratio is impressive. The impact on the quantity and quality of parent's access to food sources in many species of mammals, the sex ratio has been fixed. Previous

  15. Associations of acute stress and overnight heart rate with feed efficiency in beef heifers.

    Science.gov (United States)

    Munro, J C; Schenkel, F S; Physick-Sheard, P W; Fontoura, A B P; Miller, S P; Tennessen, T; Montanholi, Y R

    2017-03-01

    Proxies have the potential to accelerate feed efficiency (residual feed intake (RFI); kg dry matter/day) improvement, assisting with the reduction of beef cattle feed costs and environmental impact. Heart rate (HR) (beats per minute (BPM)) is associated with feed efficiency and influenced by autonomic activity and peripheral metabolism, suggesting HR could be used as a proxy for feed efficiency. Objectives were to assess associations between overnight HR, lying patterns and RFI, and between acute stress HR and RFI. Heifer calves (n=107; 408±28 days of age, 341±42.2 kg) and yearling heifers (n=36; 604±92 days of age, 539±52.2 kg) were exposed to a performance test to determine productive performance. Overnight HR (electrode based) and lying patterns (accelerometer based) were monitored on a subgroup of heifer calves (n=40; 20 lowest RFI; 20 highest RFI). In the 10-min acute stress assessment, all heifers were individually exposed to the opening and closing of an umbrella and HR before (HRBEF), in response to (HRMAX), after (HRAFT) and change (HRCHG; HRAFT-HRBEF) as a result of exposure were determined. Using polynomial regression, rate of HR decrease pre-exposure (β 1) and rates of HR increase (β 2) and decrease (β 3, β 4) post-exposure were determined. Heifer calves in the overnight assessment were classified into equal RFI groups (low RFI; high RFI) and HR means were treated as repeated measures and compared using multiple regression. In the acute stress assessment, heifers were classified within cattle category into equal RFI groups (low RFI; high RFI) and means and polynomial regression parameters were compared using multiple regression. Low-RFI heifer calves had a lower overnight HR (69.2 v. 72.6 BPM), similar HR change from lying to standing intervals (8.9 v. 9.2 BPM) and similar time lying (61.1% v. 64.5%) compared with high-RFI heifer calves. Low-RFI heifer calves had a higher absolute HRMAX (162.9 v. 145.7 BPM) and β 2 (-0.34 v. -0.20) than high

  16. Native predators living in invaded areas: responses of terrestrial amphibian species to an Argentine ant invasion.

    Science.gov (United States)

    Alvarez-Blanco, Paloma; Caut, Stephane; Cerdá, Xim; Angulo, Elena

    2017-08-22

    Predator-prey interactions play a key role in the success and impacts of invasive species. However, the effects of invasive preys on native predators have been poorly studied. Here, we first reviewed hypotheses describing potential relationships between native predators and invasive preys. Second, we examined how an invasive prey, the Argentine ant (Linepithema humile), affected a native terrestrial amphibian community. In the field, we looked at the structure of the amphibian community in invaded versus uninvaded areas and characterized amphibian trophic ecology. The amphibian community sampled seemed to show a species-dependent response in abundance to invasion: adults of the natterjack toad (Bufo calamita), the species demonstrating the highest degree of ant specialization, were less abundant in invaded areas. Although available ant biomass was significantly greater in invaded than in uninvaded areas (only Argentine ants occurred in the former), amphibians consumed relatively fewer ants in invaded areas. In the lab, we quantified amphibian consumption of Argentine ants versus native ants and assessed whether consumption patterns could have been influenced by prior exposure to the invader. The lab experiments corroborated the field results: amphibians preferred native ants over Argentine ants, and prior exposure did not influence consumption. Differences in preference explained why amphibians consumed fewer Argentine ants in spite of their greater relative availability; they might also explain why the most ant-specialized amphibians seemed to avoid invaded areas. Our results suggest the importance to account for predator feeding capacities and dietary ranges to understand the effects of invasive species at higher trophic levels.

  17. Feeding strategy and cannibalism of the Argentine hake Merluccius hubbsi.

    Science.gov (United States)

    Ocampo Reinaldo, M; González, R; Romero, M A

    2011-12-01

    The diet composition and feeding strategy of the Argentine hake Merluccius hubbsi in the San Matías Gulf were analysed in order to use this information for the sustainable management of the fishery. Merluccius hubbsi behaved as an opportunistic predator. Small M. hubbsi consumed planktonic crustaceans, whereas medium and large fish ate numerous prey taxa with low frequency of occurrence and variable specific abundance. Intra- and intercohort cannibalism were detected in all size groups and were particularly significant in large M. hubbsi. Medium-sized M. hubbsi consumed small conspecifics and large-sized M. hubbsi consumed both small and medium M. hubbsi. These results indicate that the removal of large M. hubbsi by fishing may increase the risk of overfishing by two combined effects: a direct effect of recruitment-overfishing and an indirect effect of growth-overfishing through an enhanced cannibalism of medium M. hubbsi on small M. hubbsi. Intra- and intercohort cannibalism and other trophic relationships in the M. hubbsi should therefore be considered explicitly in stock assessment models.

  18. Fragile-X mental retardation: molecular diagnosis in Argentine patients.

    Science.gov (United States)

    Florencia, Giliberto; Irene, Szijan; Veronica, Ferreiro

    2006-11-30

    Fragile-X-syndrome (FXS) is the most common type of inherited cognitive impairment. The underlying molecular alteration consists of a CGG-repeat amplification within the FMR-1 gene. The phenotype is only apparent once a threshold in the number of repeats has been exceeded (full mutation). The aim of this study was to characterize the FMR-1 CGG-repeat status in Argentine patients exhibiting mental retardation. A total of 330 blood samples from patients were analyzed by PCR and Southern blot analysis. Initially, DNA from 78 affected individuals were studied by PCR. Since this method is unable to detect high molecular weight alleles, however, we undertook a second approach using the Southern blotting technique to analyze the CGG repeat number and methylation status. Southern blot analysis showed an altered pattern in 14 out of 240 (6%) unrelated patients, with half of them presenting a mosaic pattern. Eight out of 17 families (47%) showed a (suggest deleting highlight). The characteristic FXS pattern was identified in 8/17 families (47%), and in 4 of these families 25% of the individuals presented with a mosaic model. The expansion from pre-mutation to full mutation was shown to occur both at the pre and post zygotic levels. The detection of FXS mutations has allowed us to offer more informed genetic counseling, prenatal diagnosis and reliable patient follow-up.

  19. [Distribution of Lutzomyia longipalpis in the Argentine Mesopotamia, 2010].

    Science.gov (United States)

    Salomon, Oscar D; Fernandez, Maria S; Santini, María S; Saavedra, Silvina; Montiel, Natalia; Ramos, Marina A; Rosa, Juan R; Szelag, Enrique A; Martinez, Mariela F

    2011-01-01

    The first case of visceral leishmaniasis (VL) in Argentina was reported in 2006 in Posadas, Misiones. During the summer 2008-2009 Lutzomyia longipalpis, the VL vector, and canine VL cases were already spread along the province of Corrientes. In order to know the distribution of VL risk, systematic captures of the vector were performed between February and March 2010, in 18 areas of the provinces of Entre Ríos and Corrientes, and the city of Puerto Iguazú, Misiones, with a total of 313 traps/night. We confirmed the presence of Lu. longipalpis, for the first time in Chajarí (Entre Ríos), Alvear, La Cruz, Curuzú Cuatiá and Bella Vista (Corrientes), and Puerto Iguazú (Misiones). In Santo Tome and Monte Caseros (Corrientes), where the vector had been previously reported, traps with more samples were obtained with 830 and 126 Lu. Longipalpis trap/site/night respectively. These results show that the vector of urban VL continues spreading in the Argentine territory. Simultaneously, the spread of the parasite and the resulting human VL cases are associated with the dispersion of reservoirs, infected dogs, with or without clinical symptoms or signs, due to human transit.

  20. Insecticide transfer efficiency and lethal load in Argentine ants

    Energy Technology Data Exchange (ETDEWEB)

    Hooper-Bui, L.M. [Department of Environmental Science, Louisiana State University, Baton Rouge, LA 70803 (United States); Department of Entomology, University of California, Riverside, CA 92521 (United States); Kwok, E.S.C. [Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521 (United States); Buchholz, B.A., E-mail: buchholz2@llnl.gov [Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Department of Environmental Toxicology, University of California, Davis, CA 95616 (United States); Rust, M.K. [Department of Entomology, University of California, Riverside, CA 92521 (United States); Eastmond, D.A. [Department of Cell Biology and Neuroscience, University of California, Riverside, CA 92521 (United States); Vogel, J.S. [Center for Accelerator Mass Spectrometry, Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States)

    2015-10-15

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of {sup 14}C-sucrose, {sup 14}C-hydramethylnon, and {sup 14}C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  1. BNCT for skin melanoma in extremities: Updated Argentine clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Menendez, P.R. [Instituto de Oncologia Angel H. Roffo. Av. San Martin 5481, (1417) Cdad. de Buenos Aires (Argentina)], E-mail: pmenende@yahoo.com; Roth, B.M.C. [Instituto de Oncologia Angel H. Roffo. Av. San Martin 5481, (1417) Cdad. de Buenos Aires (Argentina); Pereira, M.D. [Instituto de Oncologia Angel H. Roffo. Av. San Martin 5481, (1417) Cdad. de Buenos Aires (Argentina); Comision Nacional de Energia Atomica, Av. del Libertador 8250, (1429) Cdad. de Buenos Aires (Argentina); Agencia Nacional de Promocion Cientifica y Tecnologica. PAV 22393, Cordoba 831, (1054) Cdad. de Buenos Aires (Argentina); Casal, M.R. [Instituto de Oncologia Angel H. Roffo. Av. San Martin 5481, (1417) Cdad. de Buenos Aires (Argentina); Gonzalez, S.J. [Comision Nacional de Energia Atomica, Av. del Libertador 8250, (1429) Cdad. de Buenos Aires (Argentina); CONICET, Avda. Rivadavia 1917, (1033) Cdad. de Buenos Aires (Argentina); Feld, D.B.; Santa Cruz, G.A.; Kessler, J.; Longhino, J.; Blaumann, H.; Jimenez Rebagliati, R.; Calzetta Larrieu, O.A.; Fernandez, C.; Nievas, S.I.; Liberman, S.J. [Comision Nacional de Energia Atomica, Av. del Libertador 8250, (1429) Cdad. de Buenos Aires (Argentina)

    2009-07-15

    As part of phase I/II melanoma BNCT clinical trial conducted in Argentina in a cooperative effort of the Argentine Atomic Energy Commission (CNEA) and the Oncology Institute Angel H. Roffo (IOAHR), 7 patients (6 female-1 male) received eight treatment sessions covering ten anatomical areas located in extremities. Mean age of the patients was 64 years (51-74). The treatments were performed between October 2003 and June 2007. All patients presented multiple subcutaneous skin metastases of melanoma and received an infusion containing {approx}14 gr/m{sup 2} of {sup 10}borophenyl-alanine (BPA) followed by the exposition of the area to a mixed thermal-epithermal neutron beam at the RA-6 reactor. The maximum prescribed dose to normal skin ranged from 16.5 to 24 Gy-Eq and normal tissue administered dose varied from 15.8 to 27.5 Gy-Eq. Considering evaluable nodules, 69.3% of overall response and 30.7% of no changes were seen. The toxicity was acceptable, with 3 out of 10 evaluable areas showing ulceration (30% toxicity grade 3)

  2. Active tectonics in the Argentine Precordillera and Western Sierras Pampeanas

    Directory of Open Access Journals (Sweden)

    L.L. Siame

    2006-12-01

    Full Text Available The Andean foreland of western Argentina (28°S-33°S corresponds to retroarc deformations associated with the ongoing flat subduction of the Nazca plate beneath the South American lithosphere. This region is characterized by high levels of seismic activity and crustal active faulting. To improve earthquake source identification and characterization in the San Juan region, data from seismology, structural geology and quantitative geomorphology were integrated and combined to provide a seismotectonic model. In this seismotectonic model, the Andean back-arc of western Argentina can be regarded as an obliquely converging foreland where Plio-Quaternary deformations are partitioned between strike-slip and thrust motions that are localized on the E-verging, thin-skinned Argentine Precordillera, and the W-verging thick-skinned Sierras Pampeanas, respectively. In this seismotectonic model, the Sierra Pie de Palo appears to be a key structure playing a major role in the partitioning of the Plio-Quaternary deformations.

  3. Insecticide transfer efficiency and lethal load in Argentine ants

    Science.gov (United States)

    Hooper-Bui, L. M.; Kwok, E. S. C.; Buchholz, B. A.; Rust, M. K.; Eastmond, D. A.; Vogel, J. S.

    2015-10-01

    Trophallaxis between individual worker ants and the toxicant load in dead and live Argentine ants (Linepithema humile) in colonies exposed to fipronil and hydramethylnon experimental baits were examined using accelerator mass spectrometry (AMS). About 50% of the content of the crop containing trace levels of 14C-sucrose, 14C-hydramethylnon, and 14C-fipronil was shared between single donor and recipient ants. Dead workers and queens contained significantly more hydramethylnon (122.7 and 22.4 amol/μg ant, respectively) than did live workers and queens (96.3 and 10.4 amol/μg ant, respectively). Dead workers had significantly more fipronil (420.3 amol/μg ant) than did live workers (208.5 amol/μg ant), but dead and live queens had equal fipronil levels (59.5 and 54.3 amol/μg ant, respectively). The distribution of fipronil differed within the bodies of dead and live queens; the highest amounts of fipronil were recovered in the thorax of dead queens whereas live queens had the highest levels in the head. Resurgence of polygynous ant colonies treated with hydramethylnon baits may be explained by queen survival resulting from sublethal doses due to a slowing of trophallaxis throughout the colony. Bait strategies and dose levels for controlling insect pests need to be based on the specific toxicant properties and trophic strategies for targeting the entire colony.

  4. Spread of tetracycline resistance genes at a conventional dairy farm

    Directory of Open Access Journals (Sweden)

    Martina eKyselkova

    2015-05-01

    Full Text Available The use of antibiotics in animal husbandry contributes to the worldwide problem of increasing antibiotic resistance in animal and human pathogens. Intensive animal production is considered an important source of antibiotic resistance genes released to the environment, while the contribution of smaller farms remains to be evaluated. Here we monitor the spread of tetracycline resistance (TC-r genes at a middle-size conventional dairy farm, where chlortetracycline (CTC, as intrauterine suppository is prophylactically used after each calving. Our study has shown that animals at the farm acquired the TC-r genes in their early age (1-2 weeks, likely due to colonization with TC-resistant bacteria from their mothers and/or the farm environment. The relative abundance of the TC-r genes tet(W, tet(Q and tet(M in fresh excrements of calves was about 1-2 orders of magnitude higher compared to heifers and dairy cows, possibly due to the presence of antibiotic residues in milk fed to calves. The occurrence and abundance of TC-r genes in fresh excrements of heifers and adult cows remained unaffected by intrauterine CTC applications, with tet(O, tet(Q and tet(W representing a ‘core TC-resistome’ of the farm, and tet(A, tet(M, tet(Y and tet(X occurring occasionally. The genes tet(A, tet(M, tet(Y and tet(X were shown to be respectively harbored by Shigella, Lactobacillus and Clostridium, Acinetobacter, and Wautersiella. Soil in the farm proximity, as well as field soil to which manure from the farm was applied, was contaminated with TC-r genes occurring in the farm, and some of the TC-r genes persisted in the field over 3 months following the manure application. Concluding, our study shows that antibiotic resistance genes may be a stable part of the intestinal metagenome of cattle even if antibiotics are not used for growth stimulation, and that smaller dairy farms may also contribute to environmental pollution with antibiotic resistance genes.

  5. Physiology and Endocrinology Symposium. Factors controlling puberty in beef heifers

    Science.gov (United States)

    The Physiology and Endocrinology Symposium on “Factors controlling puberty in beef heifers” was held at the joint annual meeting of the American Dairy Science Association and the American Society of Animal Science in New Orleans, Louisiana, USA, July 10 to 14, 2011. The objective of the symposium w...

  6. Perspectives on Argentine Migration to Spain: Oral, Journal and Film Sources

    Directory of Open Access Journals (Sweden)

    Susana Schmidt

    2010-03-01

    Full Text Available This contribution takes up our doctoral research –Argentine migrationto Spain- to share some theoretical-methodological considerations.We refer to the conceptualization of "transnational social spaces," an approach that allows us to consider migration in its double dimension origin/destination and is particularly useful to thing the relationship between migration and creation of social and cultural ties in the Hispano-Argentine or Argentine-Spanish space. Similarly, the transnational spaces approach allows to put in dialog diverse social groups involved in the phenomenon: the migrants themselves, whose life stories are analysed by using oral sources; the society of origin and the host society, analysing collective image through journal sources; the filmmakers, whose migration stories we discussmigration through various fiction films; and, of course, historians and other social scientists who study these migrations.

  7. Artificial infestation of Boophilus microplus in beef cattle heifers of four genetic groups

    Directory of Open Access Journals (Sweden)

    Ana Mary da Silva

    2007-01-01

    Full Text Available Resistance of beef cattle heifers to the cattle tick Boophilus microplus was evaluated by artificial infestation of 66 beef cattle heifers of the following genetic groups: 16 Nelore (NE, 18 Canchim x Nelore (CN, 16 Angus x Nelore (AN and 16 Simmental x Nelore (SN. The animals, with a mean age of 16.5 months, were maintained with no chemical tick control in a Brachiaria decumbens pasture. Four artificial infestations with 20,000 B. microplus larvae were carried out 14 days apart and from day 18 to day 22 of each infestation the number of engorged female ticks (> 4.5 mm was counted on the left side of each heifer. Data were analyzed as the percentage of return (PR = percentage of ticks counted relative to the number infested, transformed to (PR¼, and as log10 (Cij + 1, in which Cij is the number of ticks in each infestation, using the least squares method with a model that included the effects of genetic group (GG, animal within GG (error a, infestation number (I, GG x I and the residual (error b. Results indicated a significant GG x I interaction, because AN and SN heifers had a higher percentage of return than CN and NE heifers, while CN heifers showed a higher percentage of return than the NE heifers only in infestations 3 and 4. Transformed percentages of return were NE = 0.35 ± 0.06, AN = 0.89 ± 0.06, CN = 0.54 ± 0.05 and SN = 0.85 ± 0.06.

  8. Impact of puberty status and melengestrol acetate supplementation before the breeding period on reproductive efficiency of Bos indicus beef heifers.

    Science.gov (United States)

    Martins, J H; Santos, C S; Silva, M A V; Aguiar, H M V S B; França, I G; Pereira, H G; Ribeiro, D L; Chaves, R M; Souza, J A T; Monteiro, B M; Sá Filho, M F; Torres-Júnior, J R S

    2015-06-01

    Two experiments were designed to evaluate the impact of puberty status and the administration of melengestrol acetate (MGA) before onset of the breeding period on ovulatory responses (Exp. 1) and conception rate after AI performed on estrus detection during 10 d and the pregnancy rate through 80 d of breeding period (Exp. 2) of pasture-grazed beef heifers. In Exp. 1, heifers (15 pubertal and 15 prepubertal) received 0.5 mg per heifer/d -1 of MGA over 14 d. No differences in the ovulatory responses were found 10 d after the MGA administration (pubertal = 46.7% vs. prepubertal P = 53.3%; P = 0.72). In Exp. 2, 368 heifers were randomly assigned to groups according to pubertal status and the MGA treatment. All heifers were inseminated on estrus detection for up 10 d after MGA administration and following exposure to bulls between 20 and 80 d. The MGA-treated heifers exhibited a greater AI service rate than control heifers (72.1 vs. 41.6%;P breeding period (95.3 vs. 87.5%;P breeding period. At onset of the breeding period, pubertal heifers presented a greater pregnancy rate following AI (pubertal P = 42.2% vs. prepubertal P = 24.9%; P = 0.01). Therefore, pubertal heifers seem to have greater overall reproductive efficiency than prepubertal heifers, particularly at the beginning of the breeding period. Interestingly, administration of MGA before the onset of the breeding period increased AI service rate but did not alter the rate of pregnancy throughout the breeding period of pasture-grazed beef heifers.

  9. Combined effect of hemipteran control and liquid bait on Argentine ant populations.

    Science.gov (United States)

    Brightwell, R J; Bambara, S B; Silverman, J

    2010-10-01

    The invasive Argentine ant, Linepithema humile (Mayr), has become a worldwide problem capable of inflicting significant ecological and economic injury on urban, agricultural, and natural environments. The mobility of this pest ant has long been noted, rapidly moving nests to new food resources and then away as resources are depleted. This ant, like many pest ant species, has a special affinity for honeydew excreted by phloem-feeding Hemiptera. We investigated the effect of various hemipteran control strategies on terrapin scale densities and measured their indirect effect on local Argentine ant densities and foraging effort. We then determined whether this indirect treatment strategy improved the performance of an ant bait. We predicted that Argentine ants would move nests away from trees treated for Hemiptera and then move nests back when a liquid bait was offered, followed by a decline in ant numbers due to intake of the toxicant. A horticultural oil spray and soil application of the systemic insecticide, imidacloprid, had no effect on terrapin scale numbers. However, trunk-injected dicrotophos caused a reduction in scale and a decline in local Argentine ant nest density and canopy foraging effort. We also recorded a reduction in local Argentine ant ground foraging when large amounts of liquid bait were applied, and we found no evidence that combining dicrotophos with liquid ant bait performed better than each treatment alone. We suggest that a strategy of combined hemipteran control plus application of liquid ant bait can reduce local Argentine ant densities, when both components of this system are highly efficacious.

  10. Biotic and abiotic controls of argentine ant invasion success at local and landscape scales

    Science.gov (United States)

    Menke, S.B.; Fisher, R.N.; Jetz, W.; Holway, D.A.

    2007-01-01

    Although the ecological success of introduced species hinges on biotic interactions and physical conditions, few experimental studies - especially on animals - have simultaneously investigated the relative importance of both types of factors. The lack of such research may stem from the common assumption that native and introduced species exhibit similar environmental tolerances. Here we combine experimental and spatial modeling approaches (1) to determine the relative importance of biotic and abiotic controls of Argentine ant (Linepithema humile) invasion success, (2) to examine how the importance of these factors changes with spatial scale in southern California (USA), and (3) to assess how Argentine ants differ from native ants in their environmental tolerances. A factorial field experiment that combined native ant removal with irrigation revealed that Argentine ants failed to invade any dry plots (even those lacking native ants) but readily invaded all moist plots. Native ants slowed the spread of Argentine ants into irrigated plots but did not prevent invasion. In areas without Argentine ants, native ant species showed variable responses to irrigation. At the landscape scale, Argentine ant occurrence was positively correlated with minimum winter temperature (but not precipitation), whereas native ant diversity increased with precipitation and was negatively correlated with minimum winter temperature. These results are of interest for several reasons. First, they demonstrate that fine-scale differences in the physical environment can eclipse biotic resistance from native competitors in determining community susceptibility to invasion. Second, our results illustrate surprising complexities with respect to how the abiotic factors limiting invasion can change with spatial scale, and third, how native and invasive species can differ in their responses to the physical environment. Idiosyncratic and scale-dependent processes complicate attempts to forecast where

  11. Crossbreeding heifers performance in different reproductive stage / Desempenho de novilhas mestiças em diferentes estádios reprodutivos Crossbreeding heifers performance in different reproductive stage

    Directory of Open Access Journals (Sweden)

    Fernando Zawadzki

    2010-07-01

    Full Text Available Twenty-one crossbreeding heifers (½ Nelore vs ½ Aberdeen Angus with about 307.90 kg of live weight and eighteen months of age were used in a complete randomized design with three treatments and seven repetitions. The treatments were: control heifers, ovariectomized animals and with fifty gunshot spheres in uterine corn. The heifers were fed with 50% of corn silage and 50% concentrated. The feed intake was about 2,5% weight live in dry matter. The heifers gunshot treatments showed was bigger weight gain than the heifers ovariectomized treatments and this more weight gains what control heifers treatments. There was not difference in carcass yield and fat covering amongst treatments. The hematocrito increased in three heifers groups in the first collection (before for the second collection (after treatments. However, the increase was superior (P Foram utilizadas vinte e uma novilhas mestiças ½ Nelore vs ½ Aberdeen Angus, com idade aproximada de dezoito meses e peso médio de 307,90 kg. Os animais foram distribuídos em delineamento inteiramente casualizado, com três tratamentos e sete repetições. Os tratamentos foram compostos por: novilhas vazias, novilhas ovariectomizadas e novilhas com implante de cinqüenta esferas de chumbo esterilizadas no interior do corno uterino. As novilhas foram alimentadas com ração composta de 50% silagem de milho (MS e 50% concentrado (MS, fornecida na base de 2,5% (MS do peso vivo dos animais. As novilhas com implante de chumbo apresentaram ganho médio diário superior (P < 0,05 aos das novilhas ovariectomizadas e das vazias. Ainda, as novilhas ovariectomizadas apresentam ganho superior (P < 0,05 aos das novilhas vazias. Todavia, não houve diferença no que se refere ao rendimento de carcaça e cobertura de gordura. O valor do hematócrito aumentou nos três grupos de animais da primeira coleta (antes para a segunda coleta (depois dos tratamentos. Todavia, este aumento foi maior (P < 0,05 nas novilhas

  12. Dairy production medicine

    National Research Council Canada - National Science Library

    Risco, Carlos A; Melendez Retamal, Pedro

    2011-01-01

    ... Insemination José Eduardo P . Santos Applications of Ultrasonography in Dairy Cattle Reproductive Management Jill D. Colloton 3 7 19 27 33 73 81 99 10 11 12 13 14 15 16 17 18 Diseases that Affect the Reprod...

  13. Genomic dairy cattle breeding

    DEFF Research Database (Denmark)

    Mark, Thomas; Sandøe, Peter

    2010-01-01

    The aim of this paper is to discuss the potential consequences of modern dairy cattle breeding for the welfare of dairy cows. The paper focuses on so-called genomic selection, which deploys thousands of genetic markers to estimate breeding values. The discussion should help to structure...... the thoughts of breeders and other stakeholders on how to best make use of genomic breeding in the future. Intensive breeding has played a major role in securing dramatic increases in milk yield since the Second World War. Until recently, the main focus in dairy cattle breeding was on production traits......, unfavourable genetic trends for metabolic, reproductive, claw and leg diseases indicate that these attempts have been insufficient. Today, novel genome-wide sequencing techniques are revolutionising dairy cattle breeding; these enable genetic changes to occur at least twice as rapidly as previously. While...

  14. Genomic dairy cattle breeding

    DEFF Research Database (Denmark)

    Mark, Thomas; Sandøe, Peter

    2010-01-01

    The aim of this paper is to discuss the potential consequences of modern dairy cattle breeding for the welfare of dairy cows. The paper focuses on so-called genomic selection, which deploys thousands of genetic markers to estimate breeding values. The discussion should help to structure...... the thoughts of breeders and other stakeholders on how to best make use of genomic breeding in the future. Intensive breeding has played a major role in securing dramatic increases in milk yield since the Second World War. Until recently, the main focus in dairy cattle breeding was on production traits......, unfavourable genetic trends for metabolic, reproductive, claw and leg diseases indicate that these attempts have been insufficient. Today, novel genome-wide sequencing techniques are revolutionising dairy cattle breeding; these enable genetic changes to occur at least twice as rapidly as previously. While...

  15. Embryo production in heifers with low or high dry matter intake submitted to superovulation.

    Science.gov (United States)

    Mollo, Marcos R; Monteiro, Pedro L J; Surjus, Ricardo S; Martins, Aline C; Ramos, Alexandre F; Mourão, Gerson B; Carrijo, Luiz H D; Lopes, Gláucio; Rumpf, Rodolfo; Wiltbank, Milo C; Sartori, Roberto

    2017-04-01

    This study investigated the influence of feed intake on superovulatory response and embryo production of Nelore heifers. Pubertal heifers were kept in a feedlot and were submitted to the same diets, but with different levels of feed consumption: High (1.7 M; n = 20) or Low (0.7 M; n = 19) feed intake. Heifers in the 1.7 M treatment consumed 170% (2.6% of body weight [BW] in dry matter) and the 0.7 M heifers ate 70% (1.1% of BW in dry matter) of a maintenance diet. After 7 wk on these diets, heifers were treated with eight decreasing doses of follicle-stimulating hormone (FSH) given every 12 h, totaling 133 mg Folltropin (Folltropin-V; Bioniche Animal Health, Canada) per heifer. Seven d after AI, heifers had their uteri flushed and embryos were recovered and graded according to the International Embryo Technology Society standards. Data were analyzed using the GLIMMIX procedure of SAS and results are presented as least-squares means ± SEM (P < 0.05). At the onset of the FSH treatment (Day 0 of the protocol), 1.7 M heifers had greater body condition score (BCS), BW and serum insulin concentrations than 0.7 M heifers (4.1 ± 0.1 vs. 3.0 ± 0.1; 462.5 ± 10.1 vs. 382.7 ± 10.4 kg; and 14.3 ± 1.7 vs. 3.5 ± 0.8 μIU/mL, respectively). The 0.7 M heifers had more follicles ≥6 mm at the time of the last FSH (Day 7; 47.9 ± 6.4 vs. 23.5 ± 4.3 follicles), related to a better follicle superstimulatory response to FSH. Similarly, 0.7 M heifers had more corpora lutea at the time of embryo collection (33.6 ± 1.4 vs. 15.7 ± 0.9) than the 1.7 M heifers, which resulted in greater number of recovered embryos and ova (9.9 ± 0.7 vs. 6.7 ± 0.6) and viable embryos (5.3 ± 0.5 vs. 3.8 ± 0.4), despite having similar proportions of viable embryos (∼62%). A negative correlation between circulating insulin and follicle superstimulatory response to FSH was observed (r = -0.68). Therefore, we conclude that high feed intake, for a

  16. DNA Barcoding Identifies Argentine Fishes from Marine and Brackish Waters

    Science.gov (United States)

    Mabragaña, Ezequiel; Díaz de Astarloa, Juan Martín; Hanner, Robert; Zhang, Junbin; González Castro, Mariano

    2011-01-01

    Background DNA barcoding has been advanced as a promising tool to aid species identification and discovery through the use of short, standardized gene targets. Despite extensive taxonomic studies, for a variety of reasons the identification of fishes can be problematic, even for experts. DNA barcoding is proving to be a useful tool in this context. However, its broad application is impeded by the need to construct a comprehensive reference sequence library for all fish species. Here, we make a regional contribution to this grand challenge by calibrating the species discrimination efficiency of barcoding among 125 Argentine fish species, representing nearly one third of the known fauna, and examine the utility of these data to address several key taxonomic uncertainties pertaining to species in this region. Methodology/Principal Findings Specimens were collected and morphologically identified during crusies conducted between 2005 and 2008. The standard BARCODE fragment of COI was amplified and bi-directionally sequenced from 577 specimens (mean of 5 specimens/species), and all specimens and sequence data were archived and interrogated using analytical tools available on the Barcode of Life Data System (BOLD; www.barcodinglife.org). Nearly all species exhibited discrete clusters of closely related haplogroups which permitted the discrimination of 95% of the species (i.e. 119/125) examined while cases of shared haplotypes were detected among just three species-pairs. Notably, barcoding aided the identification of a new species of skate, Dipturus argentinensis, permitted the recognition of Genypterus brasiliensis as a valid species and questions the generic assignment of Paralichthys isosceles. Conclusions/Significance This study constitutes a significant contribution to the global barcode reference sequence library for fishes and demonstrates the utility of barcoding for regional species identification. As an independent assessment of alpha taxonomy, barcodes provide

  17. Argentine experience in the field of illegal immigration.

    Science.gov (United States)

    Villar, J M

    1984-01-01

    This article provides a brief history of Argentine policy toward migratory flows from neighboring countries and Europe, and concludes with statistics on the number of foreigners in Argentina in the 1970-80 period. Measures passed during the 1940s and 1950s were aimed at providing amnesty for foreigners who were residing in Argentina without immigrant status. However, the lack of an adequate administrative structure to regulate foreigners at the borders was a drawback for migration authorities and limited the possiblility of applying admission criteria effectively. By 1970, there were 583,000 foreigners from neighboring countries living in Argentina, which represented a 25% increase from 1960. 42% of these migrants were in the metropolitan region of the country, indicative of a shift away from employment in agriculture. Decree No. 87, passed in 1974, represented an extension of a migration policy aimed at granting ample facilities for permanent residence to aliens from contiguous countries and was designed to prevent abuse of clandestine workers by employers. As a result of this measure, 150,000 foreigners were able to settle legally in the country. A 1981 law, yet to be implemented, establishes a new legal framework aimed at fostering immigration and regulating the admission of foreigners. To attain the objective of settling workers in areas of the country considered of prime importance to economic development, the law provides for infrastructural investments and promotional measures in areas such as tax exemption and the granting of credit. The 1980 National Population Census indicated there were 677,000 foreigners from neighboring countries in Argentina. In that year, foreigners comprised 2.4% of the country's population and 3.1% of the inhabitants of the metropolitan region. These figures are indicative of a decline in the growth of immigration, most likely due to the decline in the purchasing power of workers' salaries in the late 1970s.

  18. DNA barcoding identifies Argentine fishes from marine and brackish waters.

    Directory of Open Access Journals (Sweden)

    Ezequiel Mabragaña

    Full Text Available BACKGROUND: DNA barcoding has been advanced as a promising tool to aid species identification and discovery through the use of short, standardized gene targets. Despite extensive taxonomic studies, for a variety of reasons the identification of fishes can be problematic, even for experts. DNA barcoding is proving to be a useful tool in this context. However, its broad application is impeded by the need to construct a comprehensive reference sequence library for all fish species. Here, we make a regional contribution to this grand challenge by calibrating the species discrimination efficiency of barcoding among 125 Argentine fish species, representing nearly one third of the known fauna, and examine the utility of these data to address several key taxonomic uncertainties pertaining to species in this region. METHODOLOGY/PRINCIPAL FINDINGS: Specimens were collected and morphologically identified during crusies conducted between 2005 and 2008. The standard BARCODE fragment of COI was amplified and bi-directionally sequenced from 577 specimens (mean of 5 specimens/species, and all specimens and sequence data were archived and interrogated using analytical tools available on the Barcode of Life Data System (BOLD; www.barcodinglife.org. Nearly all species exhibited discrete clusters of closely related haplogroups which permitted the discrimination of 95% of the species (i.e. 119/125 examined while cases of shared haplotypes were detected among just three species-pairs. Notably, barcoding aided the identification of a new species of skate, Dipturus argentinensis, permitted the recognition of Genypterus brasiliensis as a valid species and questions the generic assignment of Paralichthys isosceles. CONCLUSIONS/SIGNIFICANCE: This study constitutes a significant contribution to the global barcode reference sequence library for fishes and demonstrates the utility of barcoding for regional species identification. As an independent assessment of alpha

  19. Lameness and Claw Lesions of the Norwegian Red Dairy Cattle Housed in Free Stalls in Relation to Environment, Parity and Stage of Lactation

    Directory of Open Access Journals (Sweden)

    Østerås O

    2005-12-01

    Full Text Available Approximately 88% of Norwegian dairy cattle are housed in tie stalls. Free stall housing for all dairy cattle will be implemented within 20 years. This means that the majority of existing stalls will be rebuilt in the near future. Fifty-seven free stall herds of the Norwegian Red breed were randomly selected and 1547 cows and 403 heifers were trimmed by 13 claw trimmers during the late winter and spring of 2002. The claw trimmers had been taught diagnosing and recording of claw lesions. Environment, management- and feeding routines were also recorded. Fifty-three herds had concrete slatted alleys while 4 had solid concrete. Thirty-five herds had concrete as a stall base, while 17 had rubber mats, 2 had wood and 3 had deep litter straw beds. The prevalence of lameness was 1.6% in hind claws. Models for lameness and claw lesions were designed to estimate the influence of different risk factors and to account for the cluster effects within herd and claw trimmer. Detected risk factors for lameness were: parity three and above and narrow cubicles; for heel horn erosions: lactation stage around 5–7 months after calving and solid concrete alleys; for haemorrhages of the white line: lactation stage around 3–5 months after calving and solid concrete alleys; for haemorrhages of the sole: parity one, lactation stage around 5–7 months after calving and short cubicles, for white line fissures: slatted concrete alleys; for asymmetrical claws: parities two and above and for corkscrewed claws: solid concrete alleys. The prevalence of lameness in heifers was low, however 29% had one or more claw lesions. Heifers that were housed in pens or free stalls had more heel-horn erosions, haemorrhages of the sole and white-line fissures than heifers in tie stalls. As new free stalls are being built, it is important to optimise the conditions for claw health.

  20. Lameness and Claw Lesions of the Norwegian Red Dairy Cattle Housed in Free Stalls in Relation to Environment, Parity and Stage of Lactation

    Directory of Open Access Journals (Sweden)

    Sogstad ÅM

    2006-12-01

    Full Text Available Approximately 88% of Norwegian dairy cattle are housed in tie stalls. Free stall housing for all dairy cattle will be implemented within 20 years. This means that the majority of existing stalls will be rebuilt in the near future. Fifty-seven free stall herds of the Norwegian Red breed were randomly selected and 1547 cows and 403 heifers were trimmed by 13 claw trimmers during the late winter and spring of 2002. The claw trimmers had been taught diagnosing and recording of claw lesions. Environment, management- and feeding routines were also recorded. Fifty-three herds had concrete slatted alleys while 4 had solid concrete. Thirty-five herds had concrete as a stall base, while 17 had rubber mats, 2 had wood and 3 had deep litter straw beds. The prevalence of lameness was 1.6% in hind claws. Models for lameness and claw lesions were designed to estimate the influence of different risk factors and to account for the cluster effects within herd and claw trimmer. Detected risk factors for lameness were: parity three and above and narrow cubicles; for heel horn erosions: lactation stage around 5–7 months after calving and solid concrete alleys; for haemorrhages of the white line: lactation stage around 3–5 months after calving and solid concrete alleys; for haemorrhages of the sole: parity one, lactation stage around 5–7 months after calving and short cubicles, for white line fissures: slatted concrete alleys; for asymmetrical claws: parities two and above and for corkscrewed claws: solid concrete alleys. The prevalence of lameness in heifers was low, however 29% had one or more claw lesions. Heifers that were housed in pens or free stalls had more heel-horn erosions, haemorrhages of the sole and white-line fissures than heifers in tie stalls. As new free stalls are being built, it is important to optimise the conditions for claw health.

  1. Performance and carcass traits of finishing heifers fed crude glycerin.

    Science.gov (United States)

    Parsons, G L; Shelor, M K; Drouillard, J S

    2009-02-01

    Crossbred heifers (n = 373; 421.6 kg +/- 28.9) were fed finishing diets containing 0, 2, 4, 8, 12, or 16% crude glycerin (DM basis). Diets consisted of steam-flaked corn with 6% alfalfa hay and 1.2% urea and provided 300 mg of monensin, 90 mg of tylosin, and 0.5 mg of melengestrol acetate per animal daily. Cattle were stratified by BW and allocated randomly, within strata, to concrete-surfaced feedlot pens each containing 6 to 7 heifers, with 9 pens per dietary treatment. Cattle were transitioned from the control diet to diets containing increasing proportions of glycerin over a period of 10 d. Cattle had ad libitum access to feed, and diets were delivered once daily throughout the 85-d trial period. As the concentration of glycerin increased, DMI decreased linearly (P glycerin had ADG of 1.19, 1.34, 1.29, 1.25, 1.17, and 1.03 kg, respectively (linear, P = 0.013; quadratic, P = 0.010). Feeding glycerin had a quadratic effect on G:F, and G:F was optimal when glycerin was fed at 2% of the diet (quadratic, P = 0.046). Glycerin increased the final BW by 12.7, 8.1, and 5.3 kg when fed at 2, 4, and 8% of the diet, respectively, but reduced the final BW by 1.9 and 14.3 kg when included at 12 and 16% of the diet (linear, P = 0.009; quadratic, P = 0.006). Similarly, HCW increased by 8.1, 5.1, and 3.3 kg when glycerin was fed at 2, 4, and 8% of the diet, respectively, but were 1.2 and 9.1 kg less than controls when glycerin was fed at 12 and 16%, respectively (linear, P = 0.009; quadratic, P = 0.006). Longissimus muscle area decreased linearly as glycerin concentrations increased (P glycerin resulted in linear decreases in subcutaneous fat over the 12th rib and marbling scores (P = 0.045). Glycerin tended to decrease the percentage of cattle grading USDA Choice (P = 0.084) and increase the percentage of cattle grading USDA Select. Adding glycerin to cattle-finishing diets improved BW gain and feed efficiency, particularly when added at concentrations of 8% or less on a DM

  2. Technical note: A new surgical technique for ovariohysterectomy during early pregnancy in beef heifers.

    Science.gov (United States)

    McLean, K J; Dahlen, C R; Borowicz, P P; Reynolds, L P; Crosswhite, M R; Neville, B W; Walden, S D; Caton, J S

    2016-12-01

    We hypothesized that a standing flank ovariohysterectomy procedure could be developed in beef heifers that would provide high quality tissues for addressing critical questions during early pregnancy, while concomitantly keeping livestock stewardship a high priority. To test the hypothesis, we: 1) developed a standing flank ovariohysterectomy procedure for use in beef heifers, and 2) implemented this procedure in a cohort of heifers up to d 50 of pregnancy for tissue collections, documentation of post-surgical recovery, and assessment of feedlot finishing performance. Ovariectomy and cesarean section protocols are well established in research and veterinary medicine and were used as starting points for procedural development. Crossbred Angus heifers ( = 46; ∼ 15 mo of age; BW = 362.3 ± 34.7 kg) were used to develop this new surgical tissue collection technique. Heifers were subjected to the 5-d CO-Synch + CIDR estrous synchronization protocol so ovariohysterectomy occurred at d 16, 22, 28, 34, 40, and 50 of gestation. Key aspects of the standing flank ovariohysterectomy technique included 1) use of local anesthetic for a standing flank incision, 2) locate the uterine and ovarian arteries via blind palpation and ligate them through the broad ligament via an improved clinch knot, 3) cut the ovaries and uterus free from the broad ligament, 4) ligate the cervix and uterine branch of the vaginal artery, and 5) cut through the cervix and remove the reproductive tract. Surgical times, from skin incision to placement of the last suture, were influenced ( = 0.04) by stage of gestation. In pregnant heifers, time decreased from d 22 (120.0 ± 12.0 min) of gestation to d 40 (79.5 ± 12.0 min) of gestation; then increased at d 50 (90.5 ± 14.7 min) of gestation. Using this procedure, we obtained uterine, placental, and embryo/fetal tissues that had experienced limited hypoxia, little or no trauma, and thus were excellent quality for scientific study. All heifers recovered

  3. Studying Present Dairy Industry Management in the Khorasan Province of Iran

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    R Valizadeh

    2013-11-01

    Full Text Available The present condition and feeds utilization of dairy industry in Khorasan province was studied in 113 dairy farms based on the official data from Ministry of Agricultural-Jehad. Questioners evaluated the required parameters. The percentage proportion of lactating cows, dry cows, pregnant heifers, virgin heifers, 6-12 months old calves, under 6 months and 3 months old calves and breeding bulls were; 39, 10, 11, 6, 15, 9, 10 and 0.1 precent, respectively. Mean of milk yield was 25.5 kg/day with fat content of 3.5%. A large variation was detected in forage quality and concentrate constituents and composition. Generally, difference between feed costs in various seasons was about 30%. All group of cows were offered more nutrients than the recommended levels. The percentage of extra feed cost in comparison with the total dairy cost of feeding was 9.1, 14.3, 15.0 and 9.1 percent for the high, medium and low milk- producing and dry cows. Most of the used concentrates were prepared in the farms. Net energy of lactation (NEL and protein contents of the hand made and factory made concentrates were 1.73±0.03 Mcal per kg dry matter, 16.1±0.8% and 1.68±0.04 Mcal per kg dry matter and 15.3±1.04%, respectively. In most of the farms, silos were non-appropriately made. It was concluded that most of the utilized rations were imbalance in energy and protein ratios. Technical attention must be regarded to the ration formulation and forage quality in the province.

  4. Environmental occurrence and shallow ground water detection of the antibiotic monensin from dairy farms

    Science.gov (United States)

    Watanabe, N.; Harter, T.H.; Bergamaschi, B.A.

    2008-01-01

    Pharmaceuticals used in animal feeding operations have been detected in various environmental settings. There is a growing concern about the impact on terrestrial and aquatic organisms and the development of antibiotic-resistant strains of microorganisms. Pharmaceutical use in milking cows is relatively limited compared with other livestock operations, except for the ionophore monensin, which is given to lactating cows as a feed. By weight, monensin can be the most significant antibiotic used in a dairy farm. This study investigates the potential of monensin to move from dairy operations into the surrounding ground water. Using two dairy farms in California as study sites, we twice collected samples along the environmental pathway-from flush lanes, lagoon waters, and shallow ground water beneath the dairies and beneath its associated manured fields. Monensin concentrations were determined using solid-phase extraction and liquid chromatography-tandem mass spectrometry with positive electrospray ionization. Monensin was detected in all of the flush lane and lagoon water samples. Theoretical maximum concentration estimated from the actual dosing rate and the theoretical excretion rate assuming no attenuation was one order of magnitude greater than observed concentrations, suggesting significant attenuation in the manure collection and storage system. Monensin was also detected, at levels ranging from 0.04 to 0.39 microg L(-1), in some of the ground water samples underneath the production area of the dairy but not from the adjacent manured fields. Concentrations in ground water immediately downgradient of the lagoons were one to two orders of magnitude lower than the concentrations detected in lagoons, suggesting attenuation in the subsurface. The data suggest the possibility of monensin transport into shallow (2-5 m) alluvial ground water from dairy management units, including manure storage lagoons and freestalls occupied by heifers, lactating cows, and dry cows.

  5. Environmental occurrence and shallow ground water detection of the antibiotic monensin from dairy farms

    Science.gov (United States)

    Watanabe, N.; Harter, T.H.; Bergamaschi, B.A.

    2008-01-01

    Pharmaceuticals used in animal feeding operations have been detected in various environmental settings. There is a growing concern about the impact on terrestrial and aquatic organisms and the development of antibiotic-resistant strains of microorganisms. Pharmaceutical use in milking cows is relatively limited compared with other livestock operations, except for the ionophore monensin, which is given to lactating cows as a feed. By weight, monensin can be the most significant antibiotic used in a dairy farm. This study investigates the potential of monensin to move from dairy operations into the surrounding ground water. Using two dairy farms in California as study sites, we twice collected samples along the environmental pathway - from flush lanes, lagoon waters, and shallow ground water beneath the dairies and beneath its associated manured fields. Monensin concentrations were determined using solid-phase extraction and liquid chromatography-tandem mass spectrometry with positive electrospray ionization. Monensin was detected in all of the flush lane and lagoon water samples. Theoretical maximum concentration estimated from the actual dosing rate and the theoretical excretion rate assuming no attenuation was one order of magnitude greater than observed concentrations, suggesting significant attenuation in the manure collection and storage system. Monensin was also detected, at levels ranging from 0.04 to 0.39 ??g L-1, in some of the ground water samples underneath the production area of the dairy but not from the adjacent manured fields. Concentrations in ground water immediately downgradient of the lagoons were one to two orders of magnitude lower than the concentrations detected in lagoons, suggesting attenuation in the subsurface. The data suggest the possibility of monensin transport into shallow (2-5 m) alluvial ground water from dairy management units, including manure storage lagoons and freestalls occupied by heifers, lactating cows, and dry cows

  6. Plasma Nesfatin-1 and Leptin in pubertal and non-pubertal Murrah buffalo heifers (Bubalus bubalis

    Directory of Open Access Journals (Sweden)

    Gorakh Nath Prajapati

    2015-12-01

    Full Text Available Buffaloes mostly suffer from delayed puberty, anestrus, sub–estrus, summer infertility, prolonged inter-calving interval and postpartum uterine disorders. Nesfatin-1 and Leptin are directly or indirectly related with body weight (BW, feed parameters and regulation of puberty. The objective of this study was to investigate the influence of Nesfatin-1 and Leptin in pubertal and non-pubertal Murrah buffalo heifers. The Murrah buffalo heifers (n=13 were randomly selected and divided into two groups; pubertal group (PG and non-pubertal group (NG. Heifers with plasma progesterone (P4 level of ≥1 ng/mL were classified as PG. Blood samples were collected at fortnight intervals for analysis of plasma Nesfatin-1, Leptin, P4, glucose and non-esterified fatty acids. Body weight, dry matter intake and feed conversion efficiency were recorded at fortnight intervals. The mean (±SEM plasma Nesfatin-1, Leptin, P4, BW and feed conversion efficiency (% were significantly (P<0.01 higher in PG as compared to NG. Dry matter intake by the heifers was also significantly (P<0.001 higher in PG than NG. Plasma metabolites (glucose and NEFA did not differ significantly between the groups. The findings of this study suggest that Nesfatin-1 and Leptin have indispensable role in the onset of puberty in buffalo heifers by affecting BW and feed parameters.

  7. Effect of diet with different energy content in growing Murrah buffalo heifers

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    G. Campanile

    2010-02-01

    Full Text Available The relationship between variations of weight and BCS was evaluated using growing buffalo heifers, fed diets with different energy level. 12 Murrah bred heifers (age: 790 days, LW: 400 kg, raised in Saint Paul (Brazil were equally divided in group H and L fed diets with 5.8 UFL/day and 3.6 UFL/day, respectively. At the end of treatment, groups showed significant differences in weight and values of BCS. In this trial each point of BCS, in Murrah heifers, seems to be equivalent to an increase and/or a loss of about 50 kg of live weight. During this trial the mean value of daily weight gain (DWG was significantly higher in group H (310 g. vs 0 g.; P<0.01. The heifers of group H required 5.4 UFL to increase the live weight, while group L showed a constant live weight in spite of the assumption of energy level of diet not sufficient to satisfy the requirements of weight maintenance. As it is known, buffalo heifers improves the efficiency of the diet utilization in case of deficiency and wastes energy when receiving diet with high energy content.

  8. Effect of intensive or extensive systems on buffalo heifers performances: onset of puberty and ovarian size

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    A. Borghese

    2010-02-01

    Full Text Available The aim of this work was to determine the effect of intensive feeding (IF group or pasture system (PS group on the onset of puberty and on the ovarian size in buffaloes. The trial was carried out on 26 prepubertal 8-months old buffalo heifers weighing a mean of 134 kg (n =13 per group. The heifers were weighed monthly and, starting from the 13th month of age, blood samples were collected every 10 days to determine the concentration of plasma progesterone by RIA. Heifers were considered to have achieved puberty and cyclic ovarian activity when plasma progesterone levels exceeded 1 ng/ml for two samples with a lower intermediate value. After two cycles, the heifers were naturally mated. Transrectal ultrasonography was performed every twenty days to follow changes in size of ovaries and in follicles number. Significantly higher (P<0.001 gains were obtained by IF system (870 g/d than PS one (620 g/d but the mean age at puberty was the same in both groups ( 599d vs 610d, respectively. Within 21 months 8 (IF group and 10 heifers (PS group showed cyclic ovarian activity. Ovarian size increased with age in both groups; however, the length of the right ovary and the number of follicles tended to be higher in IF vs PS group.

  9. Modulation of the metabolic response to an endotoxin challenge in Brahman heifers through OmniGen-AF supplementation

    Science.gov (United States)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the metabolic response of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183±5 kilograms) from the Texas AgriLife Research Center in Overton, TX, were separated into 2...

  10. OmniGen-AF supplementation modulated the physiological and acute phase responses of Brahman heifers to an endotoxin challenge

    Science.gov (United States)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the physiological and acute phase responses (APR) of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183±5 kilograms) from the Texas AgriLife Research Center in Overton...

  11. Ultrasound body composition traits response to an endotoxin challenge in Brahman heifers supplemented with Omnigen-AF

    Science.gov (United States)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the body composition traits response of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183 ± 5 kg) from the Texas AgriLife Research Center in Overton, TX, were separat...

  12. Zinc source and concentration altered physiological responses of beef heifers during a combined viral-bacterial respiratory challenge

    Science.gov (United States)

    Three treatments were evaluated in feedlot heifers to determine the effects of zinc supplementation on the immune response to a combined viral-bacterial respiratory disease challenge. Thirty-two beef heifers (255+/-15 kg) were subjected to a 30d period of Zn depletion, then randomly assigned to one ...

  13. Effect of high and low antral follicle count in pubertal beef heifers on in vitro fertilization (IVF)

    Science.gov (United States)

    Pubertal heifers can be classified between those with high (= 25) and low (= 15) antral follicle counts (AFC). The objective of this study was to determine oocyte development and maturation (e.g., fertility) in an in vitro fertilization (IVF) system for high and low AFC heifers. From a pool of 120...

  14. In vitro fertilization (IVF) from low or high antral follicle count pubertal beef heifers using semi-defined culture conditions

    Science.gov (United States)

    Antral follicle counts (AFC) vary among pubertal beef heifers. Our objective was to compare the in vitro maturation and fertilization of oocytes collected from low and high AFC heifers. Previously we reported results using serum-based IVF media and in this study report results using semi-defined m...

  15. Hair coat characteristics in Friesian heifers in the Netherlands and Kenya : experimental data and a review of literature

    NARCIS (Netherlands)

    Udo, H.M.J.

    1978-01-01

    The export of about 2600 Friesian heifers to Kenya between 1971-1973 provided an opportunity of studying the adaptation problems experienced by these heifers. Within the framework of the NUFFIC (Netherlands Universities Foundation for International Cooperation) a research project entitled

  16. The effect of yeast cell wall supplementation on the physiological and acute phase responses of crossbred heifers to endotoxin challenge

    Science.gov (United States)

    A study was conducted to determine the effect of feeding yeast cell wall (YCW) products on the physiological and acute phase responses of crossbred newly-received heifers to endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.9+/-2.4 kg) were obtained from commercial sale barns and tra...

  17. The effect of yeast cell wall supplementation on the metabolic responses of crossbred heifers to endotoxin challenge

    Science.gov (United States)

    This study examined the effect of feeding yeast cell wall (YCW) products on the metabolic responses of newly-received heifers to endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.9±2.4 kg) were obtained from commercial sale barns and transported to the Texas Tech University Beef Cent...

  18. Yeast cell wall supplementation alters the physiological and acute phase responses of crossbred heifers to an endotoxin challenge

    Science.gov (United States)

    A study was conducted to determine the effect of feeding yeast cell wall (YCW) products on the physiological and acute phase responses of crossbred newly-received heifers to an endotoxin challenge. Heifers (n = 24; 219 ± 2.4 kg) were separated into treatment groups receiving a Control diet (n = 8), ...

  19. Dried citrus pulp modulates the physiological and acute phase responses of crossbred heifers to an endotoxin challenge

    Science.gov (United States)

    This study examined the effect of feeding dried citrus pulp (CP) pellets on the physiological and acute phase responses (APR) of newly-received crossbred heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.3±2.4 kg) were obtained from commercial sale barns and transported...

  20. Relationship of feed efficiency of replacement beef heifers to subsequent feed efficiency as 3-year old suckled beef cows

    Science.gov (United States)

    We determined the correlaton between Residual Feed Intake (RFI) measured as post-weaned growing heifers (phase 1) and RFI measured as lactating beef cows (phase 2) in the same cohort. Individual performance and daily DMI were evaluated in 74 yearling heifers, and were subsequently reevaluated upon t...

  1. Genetic variability and population structure in loci related to milk production traits in native Argentine Creole and commercial Argentine Holstein cattle

    Directory of Open Access Journals (Sweden)

    Golijow C.D.

    1999-01-01

    Full Text Available Many cattle breeds have been subjected to high selection pressure for production traits. Consequently, population genetic structure and allelic distribution could differ in breeds under high selection pressure compared to unselected breeds. Analysis of k-casein, aS1-casein and prolactin gene frequencies was made for Argentine Creole (AC and Argentine Holstein (AH cattle herds. The calculated FST values measured the degree of genetic differentiation of subpopulations, depending on the variances of gene frequencies.The AC breed had considerably more variation among herds at the aS1-casein and k-casein loci. Conservation strategies should consider the entire AC population in order to maintain the genetic variability found in this native breed.

  2. Kinetics of anti-Neospora antibodies during the period of two consecutive pregnancies in chronically infected dairy cows.

    Science.gov (United States)

    Špilovská, Silvia; Moskwa, Bożena; Reiterová, Katarina

    2013-12-01

    The course of anti-Neospora antibody kinetics during two consecutive pregnancies has been evaluated in five chronically infected dairy cows. The blood samples of cows were collected monthly. Anti-Neospora antibodies in blood sera were detected by indirect ELISA (ID-VET, France). During whole period of the study cows remained seropositive; with S/P% values (iELISA) ranging from 94 to 214%. The antibody kinetics determined by iELISA showed a significant increase (PNeospora from mothers to offspring in the herd, dam-daughter serology was performed. Anti-Neospora antibodies was found in 4 from 6 heifers (>6 months old). Study presents original data reporting on the very similar persistent pattern of anti-Neospora antibody levels during the third trimester of pregnancies in all five dairies. Based on the high seropositivity of female offspring, the reactivation of a latent infection of cows rather than a re-infection can be supposed.

  3. Vitamin D status of dairy cattle: Outcomes of current practices in the dairy industry.

    Science.gov (United States)

    Nelson, Corwin D; Lippolis, John D; Reinhardt, Timothy A; Sacco, Randy E; Powell, Jessi L; Drewnoski, Mary E; O'Neil, Matthew; Beitz, Donald C; Weiss, William P

    2016-12-01

    The need for vitamin D supplementation of dairy cattle has been known for the better part of the last century and is well appreciated by dairy producers and nutritionists. Whether current recommendations and practices for supplemental vitamin D are meeting the needs of dairy cattle, however, is not well known. The vitamin D status of animals is reliably indicated by the concentration of the 25-hydroxyvitamin D [25(OH)D] metabolite in serum or plasma, with a concentration of 30ng/mL proposed as a lower threshold for sufficiency. The objective of this study was to determine the typical serum 25(OH)D concentrations of dairy cattle across various dairy operations. The serum 25(OH)D concentration of 702 samples collected from cows across various stages of lactation, housing systems, and locations in the United States was 68±22ng/mL (mean ± standard deviation), with the majority of samples between 40 and 100ng/mL. Most of the 12 herds surveyed supplemented cows with 30,000 to 50,000 IU of vitamin D3/d, and average serum 25(OH)D of cows at 100 to 300 DIM in each of those herds was near or above 70ng/mL regardless of season or housing. In contrast, average serum 25(OH)D of a herd supplementing with 20,000 IU/d was 42±15ng/mL, with 22% below 30ng/mL. Cows in early lactation (0 to 30d in milk) also had lower serum 25(OH)D than did mid- to late-lactation cows (57±17 vs. 71±20ng/mL, respectively). Serum 25(OH)D of yearling heifers receiving 11,000 to 12,000 IU of vitamin D3/d was near that of cows at 76±15ng/mL. Serum 25(OH)D concentrations of calves, on the other hand, was 15±11ng/mL at birth and remained near or below 15ng/mL through 1mo of age if they were fed pasteurized waste milk with little to no summer sun exposure. In contrast, serum 25(OH)D of calves fed milk replacer containing 6,600 and 11,000 IU of vitamin D2/kg of dry matter were 59±8 and 98±33ng/mL, respectively, at 1mo of age. Experimental data from calves similarly indicated that serum 25(OH

  4. Dopamine action in prepubertal Nelore heifers growth hormone secretion

    Directory of Open Access Journals (Sweden)

    Emiliana Oliveira Santana Batista

    2014-06-01

    Full Text Available The aim of this study was to evaluate the response of dopamine in the growth hormone secretion (GH during Nellore heifer’s sexual maturation. The animals were randomly assigned into two experimental groups: Sulpiride group (dopamine D2 antagonist, 0.59 mg/kg, S.C. and control group (saline solution S.C. at 8, 12 and 16 months of age. Blood samples were collected every 15 min for 10h after drug injection. Growth hormone was quantified by RIA, sensitivity (0.25 ng/mL and intra and inter-assay variation coefficients were 15% and 17%, respectively. GH concentration was higher in sulpiride group than control group at 8 mo (10.1 ± 0.38 ng/mL vs 4.3 ± 0.34 ng/mL; P 0.05 in total GH secretion area, total peak area and maximum peak amplitude. These results suggested an inhibitory dopamine effect on GH secretion in pre-pubertal Nellore heifers that decreases according to age.

  5. [The effect of Fenbion, an anthelmintic, on blood in heifers].

    Science.gov (United States)

    Pjescak, M; Kovác, S; Cernek, J

    1991-02-01

    The complex effects of the anthelminthic Fenbion (prepared on the basis of fenbendazole, Bioveta Nitra) were investigated; its effects on the blood picture were studied in heifers with the liveweight of 400 kg, until the sixth day after its single application at doses of 15 and 30 mg per kg liveweight. The haemoglobin (Hb) content decreased in keeping with the physiological standard. The haematocrit (Hk) value decreased below the reference standard from 0.31 and 0.32 l per l on days five and six to 0.28-0.29 l per l. The total leucocyte counts increased from 8.60-9.64 G per l to 10.54-11.0 G per 1. This means that on the first days after administration Fenbion has negative effects on erythropoiesis, and as a stressor it evokes defense reactions of the organism. Differential blood counting: leucocyte counts increased to 0.71-0.73 arb. u. on days three to four. The increase in lymphocyte counts in the blood after Fenbion administration is likely to be related to the cellular immunobiological defense reaction of the organism. The counts of segmented leucocytes decreased, the counts of eosinophils increased irregularly, those of basophils and monocytes were highly variable, and the counts of monocytes increased irregularly in a large span, or they decreased.

  6. Behavioural and chemical evidence for multiple colonisation of the Argentine ant, Linepithema humile, in the Western Cape, South Africa.

    Science.gov (United States)

    Mothapo, Natasha P; Wossler, Theresa C

    2011-02-03

    The Argentine ant, Linepithema humile, is a widespread invasive ant species that has successfully established in nearly all continents across the globe. Argentine ants are characterised by a social structure known as unicoloniality, where territorial boundaries between nests are absent and intraspecific aggression is rare. This is particularly pronounced in introduced populations and results in the formation of large and spatially expansive supercolonies. Although it is amongst the most well studied of invasive ants, very little work has been done on this ant in South Africa. In this first study, we investigate the population structure of Argentine ants in South Africa. We use behavioural (aggression tests) and chemical (CHC) approaches to investigate the population structure of Argentine ants within the Western Cape, identify the number of supercolonies and infer number of introductions. Both the aggression assays and chemical data revealed that the Western Cape Argentine ant population can be divided into two behaviourally and chemically distinct supercolonies. Intraspecific aggression was evident between the two supercolonies of Argentine ants with ants able to discriminate among conspecific non-nestmates. This discrimination is linked to the divergence in cuticular hydrocarbon profiles of ants originating from the two supercolonies. The presence of these two distinct supercolonies is suggestive of at least two independent introductions of this ant within the Western Cape. Moreover, the pattern of colonisation observed in this study, with the two colonies interspersed, is in agreement with global patterns of Argentine ant invasions. Our findings are of interest because recent studies show that Argentine ants from South Africa are different from those identified in other introduced ranges and therefore provide an opportunity to further understand factors that determine the distributional and spread patterns of Argentine ant supercolonies.

  7. Behavioural and chemical evidence for multiple colonisation of the Argentine ant, Linepithema humile, in the Western Cape, South Africa

    Directory of Open Access Journals (Sweden)

    Wossler Theresa C

    2011-02-01

    Full Text Available Abstract Background The Argentine ant, Linepithema humile, is a widespread invasive ant species that has successfully established in nearly all continents across the globe. Argentine ants are characterised by a social structure known as unicoloniality, where territorial boundaries between nests are absent and intraspecific aggression is rare. This is particularly pronounced in introduced populations and results in the formation of large and spatially expansive supercolonies. Although it is amongst the most well studied of invasive ants, very little work has been done on this ant in South Africa. In this first study, we investigate the population structure of Argentine ants in South Africa. We use behavioural (aggression tests and chemical (CHC approaches to investigate the population structure of Argentine ants within the Western Cape, identify the number of supercolonies and infer number of introductions. Results Both the aggression assays and chemical data revealed that the Western Cape Argentine ant population can be divided into two behaviourally and chemically distinct supercolonies. Intraspecific aggression was evident between the two supercolonies of Argentine ants with ants able to discriminate among conspecific non-nestmates. This discrimination is linked to the divergence in cuticular hydrocarbon profiles of ants originating from the two supercolonies. Conclusions The presence of these two distinct supercolonies is suggestive of at least two independent introductions of this ant within the Western Cape. Moreover, the pattern of colonisation observed in this study, with the two colonies interspersed, is in agreement with global patterns of Argentine ant invasions. Our findings are of interest because recent studies show that Argentine ants from South Africa are different from those identified in other introduced ranges and therefore provide an opportunity to further understand factors that determine the distributional and spread

  8. Relationship between phenotype, carcass characteristics and the incidence of dark cutting in heifers.

    Science.gov (United States)

    Mahmood, S; Basarab, J A; Dixon, W T; Bruce, H L

    2016-11-01

    Previous research has suggested that cattle predisposed to dark cutting can be identified from live animal or carcass characteristics. This hypothesis was tested using production and phenotype data from an existing data set collected from heifers (n=467) on study at three farms. Carcasses in the data set graded Canada AAA (n=136), AA (n=296), A (n=14), and B4 (dark cutting, n=21). Farm was identified as significant (P=0.0268) by CATMOD analysis and slaughter weight and carcass weight accounted for the variation in dark cutting frequency across the farms. Analysis of variance indicated that dark cutting heifers had reduced weight at weaning (Pcutting was decreased in heifers slaughtered at live weight greater than 550kg and in carcasses weighing greater than 325kg.

  9. Schooling and Governance: Pedagogical Knowledge and Bureaucratic Expertise in the Genesis of the Argentine Educational System

    Science.gov (United States)

    Southwell, Myriam

    2013-01-01

    The consolidation of the Argentine Federal Government by the 1870s aimed to modernise local society, establish state institutions and reach political stabilisation. Building a modern schooling system articulated both utopia and bureaucracy by establishing the use of knowledge as an instrument of social intervention, vindicating and legitimising…

  10. English as an Instrumental Language: Language Displacement in the Anglo-Argentine Community.

    Science.gov (United States)

    Cortes-Conde, Florencia

    1994-01-01

    Surveyed 99 Anglo-Argentine students aged 10 through 18 at five Spanish-English bilingual schools in Buenos Aires about their language attitudes and usage. It found that, despite the prestige of the English language, Spanish had become the dominant language for most. Age and place of residency in Buenos Aires also had a significant effect on…

  11. Argentine Hydrellia Robineau-Desvoidy (Diptera, Ephydridae): new species and key to identification.

    Science.gov (United States)

    Rodrigues Júnior, Francisco De Assis; Mathis, Wayne Nielsen; Hauser, Martin

    2015-05-13

    Hydrellia egeriae sp. nov., a new species of Hydrellia from Campana (34 14' 04 S, 58 52' 32 W) and Hurlingham (3435'14 S, 5838'27 W), Buenos Aires province, Argentina is described. A key to the Argentine Hydrellia species is presented.

  12. High-resolution stable isotope stratigraphy of the upper Cambrian and Ordovician in the Argentine Precordillera

    DEFF Research Database (Denmark)

    Sial, A.N.; Peralta, S.; Gaucher, C.

    2013-01-01

    We report the occurrence of important carbon isotope excursions in early Paleozoic formations of the Eastern and Central Argentine Precordillera. The Steptoean positive isotope carbon excursion (SPICE) is known from North America, Kazakhstan, South China, Australia and South America, and the nega...

  13. Draft genome of the globally widespread and invasive Argentine ant (Linepithema humile).

    Science.gov (United States)

    Smith, Christopher D; Zimin, Aleksey; Holt, Carson; Abouheif, Ehab; Benton, Richard; Cash, Elizabeth; Croset, Vincent; Currie, Cameron R; Elhaik, Eran; Elsik, Christine G; Fave, Marie-Julie; Fernandes, Vilaiwan; Gadau, Jürgen; Gibson, Joshua D; Graur, Dan; Grubbs, Kirk J; Hagen, Darren E; Helmkampf, Martin; Holley, Jo-Anne; Hu, Hao; Viniegra, Ana Sofia Ibarraran; Johnson, Brian R; Johnson, Reed M; Khila, Abderrahman; Kim, Jay W; Laird, Joseph; Mathis, Kaitlyn A; Moeller, Joseph A; Muñoz-Torres, Monica C; Murphy, Marguerite C; Nakamura, Rin; Nigam, Surabhi; Overson, Rick P; Placek, Jennifer E; Rajakumar, Rajendhran; Reese, Justin T; Robertson, Hugh M; Smith, Chris R; Suarez, Andrew V; Suen, Garret; Suhr, Elissa L; Tao, Shu; Torres, Candice W; van Wilgenburg, Ellen; Viljakainen, Lumi; Walden, Kimberly K O; Wild, Alexander L; Yandell, Mark; Yorke, James A; Tsutsui, Neil D

    2011-04-05

    Ants are some of the most abundant and familiar animals on Earth, and they play vital roles in most terrestrial ecosystems. Although all ants are eusocial, and display a variety of complex and fascinating behaviors, few genomic resources exist for them. Here, we report the draft genome sequence of a particularly widespread and well-studied species, the invasive Argentine ant (Linepithema humile), which was accomplished using a combination of 454 (Roche) and Illumina sequencing and community-based funding rather than federal grant support. Manual annotation of >1,000 genes from a variety of different gene families and functional classes reveals unique features of the Argentine ant's biology, as well as similarities to Apis mellifera and Nasonia vitripennis. Distinctive features of the Argentine ant genome include remarkable expansions of gustatory (116 genes) and odorant receptors (367 genes), an abundance of cytochrome P450 genes (>110), lineage-specific expansions of yellow/major royal jelly proteins and desaturases, and complete CpG DNA methylation and RNAi toolkits. The Argentine ant genome contains fewer immune genes than Drosophila and Tribolium, which may reflect the prominent role played by behavioral and chemical suppression of pathogens. Analysis of the ratio of observed to expected CpG nucleotides for genes in the reproductive development and apoptosis pathways suggests higher levels of methylation than in the genome overall. The resources provided by this genome sequence will offer an abundance of tools for researchers seeking to illuminate the fascinating biology of this emerging model organism.

  14. Development of a Pheromone-Assisted Baiting Technique for Argentine Ants (Hymenoptera: Formicidae).

    Science.gov (United States)

    Welzel, Kevin F; Choe, Dong-Hwan

    2016-02-24

    Current control measures for Argentine ants, Linepithema humile (Mayr), in urban settings typically include perimeter applications of insecticides around structures, resulting in potential problems with insecticide runoff and environmental contamination. Insecticidal baits can be an effective alternative to perimeter spray applications and are largely considered target-specific with minimal nontarget impact and environmental contamination. We report a "pheromone-assisted baiting technique" as an economically viable approach to maximize the efficacy of conventional baits targeting Argentine ants. Laboratory experiments with a commercially available gel bait indicated that foraging activity and final mortality of Argentine ants were significantly improved by incorporating (Z)-9-hexadecenal in the bait. The field study demonstrated that the pheromone-treated gel bait achieved a 74% reduction in Argentine ant activity by the end of 4 wk when it was compared with its own pretreatment value. This was a significant improvement over the untreated gel bait that provided a 42% reduction over the same period of time. The pheromone-assisted baiting technique has the potential in providing effective ant control with reduced amount of insecticides applied in the environment. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Applied Ecology and Control of Imported Fire Ants and Argentine Ants

    Science.gov (United States)

    The red imported fire ant, Solenopsis invicta Buren, and Argentine ant, Linepithema humile (Mayr), are invasive species that are major pests in urban, natural, and agricultural habitats. The goal of this dissertation was to study aspects the chemical sensitivity, behavior, and ecology of each specie...

  16. Optimizing breeding decisions for Finnish dairy herds.

    Science.gov (United States)

    Rajala-Schultz, P J; Gröhn, Y T; Allore, H G

    2000-01-01

    The purpose of this study was to determine the effect of reproductive performance on profitability and optimal breeding decisions for Finnish dairy herds. We used a dynamic programming model to optimize dairy cow insemination and replacement decisions. This optimization model maximizes the expected net revenues from a given cow and her replacements over a decision horizon. Input values and prices reflecting the situation in 1998 in Finland were used in the study. Reproductive performance was reflected in the model by overall pregnancy rate, which was a function of heat detection and conception rate. Seasonality was included in conception rate. The base run had a pregnancy rate of 0.49 (both heat detection and conception rate of 0.7). Different scenarios were modeled by changing levels of conception rate, heat detection, and seasonality in fertility. Reproductive performance had a considerable impact on profitability of a herd; good heat detection and conception rates provided an opportunity for management control. When heat detection rate decreased from 0.7 to 0.5, and everything else was held constant, net revenues decreased approximately 2.6%. If the conception rate also decreased to 0.5 (resulting in a pregnancy rate of 0.25), net revenues were approximately 5% lower than with a pregnancy rate of 0.49. With lower fertility, replacement percentage was higher and the financial losses were mainly from higher replacement costs. Under Finnish conditions, it is not optimal to start breeding cows calving in spring and early summer immediately after the voluntary waiting period. Instead, it is preferable to allow the calving interval to lengthen for these cows so that their next calving is in the fall. However, cows calving in the fall should be bred immediately after the voluntary waiting period. Across all scenarios, optimal solutions predicted most calvings should occur in fall and the most profitable time to bring a replacement heifer into a herd was in the fall. It

  17. Powerful motors: Kinship, citizenship and the transformation of the Argentine oil industry

    Science.gov (United States)

    Shever, Elana

    The privatization of the Argentine oil industry has been described as an unprecedented transfer of property, capital and control from the state to the corporate sphere, but this study demonstrates that the privatization process is better understood as a transformation of the historical configurations of oil-fueled development, political communities and human subjectivities. This dissertation probes the development of the state-led oil industry, and the shift to a corporate-led one, through an ethnography of Argentines differently positioned in relation to the global oil industry. The ethnography explores the lives of middle class oil workers and their families in Northwest Patagonia, impoverished residents of the shanty neighborhoods near the refineries in metropolitan Buenos Aires, and affluent employees of the translocal corporations operating in the Argentine oil fields. After the Introduction delineates this study's four principal interventions into anthropological scholarship, each subsequent chapter engages a particular problem that cuts across the Argentine oil fields and the anthropological theoretical fields. Chapter Two scrutinizes the historical construction of the Argentine subterritory as a "natural" space of value. Chapters Three and Four investigate the articulation of capitalist production and filial reproduction. These chapters argue that sentiment is a crucial generative force that has shaped the oil industry, company towns and worker families from the founding of the state-owned oil company in beginning of the twentieth century to its conversion into a corporate-owned one at the century's close. Chapters Five and Six examine the emergence of consumer citizenship and corporate citizenship out of Argentine neoliberalismo and its transformation of the oil industry. They argue that consumer and corporate citizenship are both reformulations of the older traditions of liberalism and Peronism. All the chapters of this dissertation illustrate that the

  18. Forage fiber effects on particle size reduction, ruminal stratification, and selective retention in heifers fed highly digestible grass/clover silages.

    Science.gov (United States)

    Schulze, A K S; Weisbjerg, M R; Storm, A C; Nørgaard, P

    2014-06-01

    The objective of this study was to investigate the effect of NDF content in highly digestible grass/clover silage on particle size reduction, ruminal stratification, and selective retention in dairy heifers. The reduction in particle size from feed to feces was evaluated and related to feed intake, chewing activity, and apparent digestibility. Four grass/clover harvests (Mixtures of Lolium perenne, Trifolium pratense, and Trifolium repens) were performed from early May to late August at different maturities, at different regrowth stages, and with different clover proportions, resulting in silages with NDF contents of 312, 360, 371, and 446 g/kg DM, respectively, and decreasing NDF digestibility with greater NDF content. Four rumen-fistulated dairy heifers were fed silage at 90% of ad libitum level as the only feed source in a 4 × 4 Latin square design. Silage, ingested feed boluses, medial and ventral ruminal digesta, and feces samples were washed with neutral detergent in nylon bags of 10-μm pore size, freeze dried, and divided into small (1 mm) particles by dry-sieving. Chewing activity, rumen pool size, and apparent digestibility were measured. Intake of NDF increased linearly from 2.3 to 2.8 kg/d with greater NDF content of forages (P = 0.01), but silages were exposed to similar eating time (P = 0.55) and rumination time per kg NDF (P = 0.35). No linear effect of NDF content was found on proportion of LP in ingested feed boluses (P = 0.31), medial rumen digesta (P = 0.95), ventral rumen digesta (P = 0.84), and feces (P = 0.09). Greater proportions of DM (P silages (P > 0.13). The LP proportion was >30% of particles in the ventral and medial rumen, whereas in the feces, the LP proportion was silages, stressing that the retention mechanism of large undigested particles lies elsewhere than with particle entrapment in the rumen mat. In this study, forage particle breakdown, ruminal stratification, and retention of particles in the rumen were not affected by NDF

  19. The effect of pregnancy on visceral growth and energy use in beef heifers.

    Science.gov (United States)

    Scheaffer, A N; Caton, J S; Bauer, M L; Redmer, D A; Reynolds, L P

    2003-07-01

    Beef heifers (24 mo; 378 +/- 32 kg of BW; 22 pregnant, PR; 17 nonpregnant, NP) were grouped in common pens and fed corn silage- and hay-based diets formulated to provide an ADG of 0.45 kg in NP heifers. Both PR and NP heifers were slaughtered on d 40, 120, 200, and 270 of the study. Intestinal and hepatic tissues were analyzed for protein, DNA, RNA (mg/g of fresh tissue), and in vitro oxygen use. Jejunal samples were analyzed for cellular proliferation via immunohistochemical analysis. For ileum, DNA, which provides an estimate of cell number per unit of tissue, revealed an interaction (P = 0.06) between pregnancy and slaughter day; both PR and NP decreased with time, but NP increased on d 270 (P = 0.09). Cell number in the ileum was reduced at d 200 and 270 in the PR heifers (P 0.10) by pregnancy or day. Energy use (kcal/d) of duodenum and jejunum, calculated from in vitro oxygen consumption, increased linearly (P < 0.02) with time for both PR and NP. Pregnant and NP ileal energy use increased linearly (P < 0.01), but ileal energy use by PR was less throughout gestation (P = 0.07) than ileal energy use by NP. Cellular proliferation in the crypt region of the jejunum was decreased on d 120 and 200 (P < 0.02). These data indicate that the small intestine and liver of PR heifers may conserve energy expenditure compared with NP heifers. Energy conservation can partially be explained by differences in growth and cell proliferation and by energy use of the liver and small intestine.

  20. Luteolytic effectiveness of Preloban® or Croniben® products in holstein heifers

    Directory of Open Access Journals (Sweden)

    Alfredo José Ferreira Melo

    2014-03-01

    Full Text Available The objective was to evaluate the effect of intramuscular injection of two different commercial products of cloprostenol (Preloban® or Croniprest® on luteal regression of Holstein heifers. On a random day of the estrous cycle, 36 heifers were synchronized with an estradiol-progestin-PG-estradiol treatment. Twelve days after withdrawal of progestin, heifers were randomly divided into 3 groups of 12 animals. Groups 1 and 2 received the equivalent of 150 µg of d-cloprostenol of Croniben® or Preloban® products, while group 3 received 2 ml of saline. Estrus was detected with the aid of the dispositive Estrotec® on the following five days, and heifers that expressed estrus were inseminated. Blood samples were collected daily during the periods of 0, 24, 48 and 72 hours after the injection of d-cloprostenol for measurement of plasma progesterone by radioimmunoassay. Pregnancy diagnosis was performed by ultrasonography 40 days after insemination. The interval between the manifestation of estrus and the Croniben® or Preloban® injection was 68.4 ± 4.4 and 63.3 ± 4.6 hours, respectively (P>0.05. The distribution of estrus occurred in the period of 36 to 108 hours. With the exception of two heifers with incomplete luteolysis, all animals treated with d-cloprostenol showed complete luteolysis. The conception rate was 50.0% and 54.5% for Preloban® and Croniben® treatments, respectively (P > 0.05. We conclude that Preloban® and Croniben® products have similar effectiveness to induce luteolysis and and to synchronize the estrus of Holstein heifers. Thus, producer may choose any one of them without risk of compromising reproductive performance.

  1. Candidate Gene Expression in Bos indicus Ovarian Tissues: Prepubertal and Postpubertal Heifers in Diestrus

    Science.gov (United States)

    Weller, Mayara Morena Del Cambre Amaral; Fortes, Marina Rufino S.; Porto-Neto, Laercio R.; Kelly, Matthew; Venus, Bronwyn; Kidd, Lisa; do Rego, João Paulo Arcelino; Edwards, Sophia; Boe-Hansen, Gry B.; Piper, Emily; Lehnert, Sigrid A.; Guimarães, Simone Eliza Facioni; Moore, Stephen Stewart

    2016-01-01

    Growth factors such as bone morphogenetic proteins 6, 7, 15, and two isoforms of transforming growth factor-beta (BMP6, BMP7, BMP15, TGFB1, and TGFB2), and insulin-like growth factor system act as local regulators of ovarian follicular development. To elucidate if these factors as well as others candidate genes, such as estrogen receptor 1 (ESR1), growth differentiation factor 9 (GDF9), follicle-stimulating hormone receptor (FSHR), luteinizing hormone receptor (LHR), bone morphogenetic protein receptor, type 2 (BMPR2), type 1 insulin-like growth factor receptor (IGFR1), and key steroidogenic enzymes cytochrome P450 aromatase and 3-β-hydroxysteroid dehydrogenase (CYP19A1 and HSD3B1) could modulate or influence diestrus on the onset of puberty in Brahman heifers, their ovarian mRNA expression was measured before and after puberty (luteal phase). Six postpubertal (POST) heifers were euthanized on the luteal phase of their second cycle, confirmed by corpus luteum observation, and six prepubertal (PRE) heifers were euthanized in the same day. Quantitative real-time PCR analysis showed that the expression of FSHR, BMP7, CYP19A1, IGF1, and IGFR1 mRNA was greater in PRE heifers, when contrasted to POST heifers. The expression of LHR and HSD3B1 was lower in PRE heifers. Differential expression of ovarian genes could be associated with changes in follicular dynamics and different cell populations that have emerged as consequence of puberty and the luteal phase. The emerging hypothesis is that BMP7 and IGF1 are co-expressed and may modulate the expression of FSHR, LHR and IGFR1, and CYP19A1. BMP7 could influence the downregulation of LHR and upregulation of FSHR and CYP19A1, which mediates the follicular dynamics in heifer ovaries. Upregulation of IGF1 expression prepuberty, compared to postpuberty diestrus, correlates with increased levels FSHR and CYP19A1. Thus, BMP7 and IGF1 may play synergic roles and were predicted to interact, from the expression data (P = 0.07, r

  2. Dairy products and cancer.

    Science.gov (United States)

    Lampe, Johanna W

    2011-10-01

    Cancer is a group of more than 100 diseases in which cells display uncontrolled growth, invasion, and sometimes metastasis. Milk and dairy products contain micronutrients and several bioactive constituents that may influence cancer risk and progression. Much of the focus of human, population-based studies has been on the effects of intake of milk and total dairy products or of calcium intake. Based on a systematic review of the epidemiologic literature, the World Cancer Research Fund and American Institute for Cancer Research report concluded there was a probable association between milk intake and lower risk of colorectal cancer, a probable association between diets high in calcium and increased risk of prostate cancer, and limited evidence of an association between milk intake and lower risk of bladder cancer. For other cancers, the evidence was mixed or lacking. Since the 2007 report, several additional, large-cohort studies have been published, including two that show an inverse association between intake of cultured dairy products and bladder cancer. Little is known about the potential effect of various bioactives produced during rumen microbe metabolism on cancer risk. Furthermore, studies support a role of live microbes present in some dairy products in the modulation of the human gut microbial community and gut metabolism. Given the growing appreciation for the role of the gut microbial community in relation to immune function and health and disease, including cancer, the potential role of various dairy products in the modulation of the human gut microbiome warrants further evaluation. Key teaching points: As a dietary exposure, dairy products are a complex group of foods and composition varies by region, which makes evaluation of their association with disease risk difficult. For most cancers, associations between cancer risk and intake of milk and dairy products have been examined only in a small number of cohort studies, and data are inconsistent or

  3. Trophic ecology of invasive Argentine ants in their native and introduced ranges.

    Science.gov (United States)

    Tillberg, Chadwick V; Holway, David A; Lebrun, Edward G; Suarez, Andrew V

    2007-12-26

    Although the ecological effects of invasions often become obvious soon after introduced species become established, more gradual effects may take years to manifest and can thus require long-term data for quantification. We analyzed an 8-year record of stable isotope data on Argentine ants (Linepithema humile) from southern California to infer how the trophic position of this widespread invasive species changes over time as native ant species are displaced. We couple this longitudinal analysis with a biregional comparison of stable isotope data (delta(15)N) on ants from Argentina (native range) and California (introduced range) to quantify (i) how the trophic position of L. humile differs between native and introduced populations, and (ii) how relative trophic position as estimated by delta(15)N values of Argentine ants compare with those of other ants at the same site. Both long-term and biregional comparisons indicate that the Argentine ant's relative trophic position is reduced at sites with a longer history of occupation. Over the course of 8 years, the relative trophic position of L. humile remained high at the leading edge of an invasion front but declined, on average, behind the front as native ants disappeared. Relative to native populations, where L. humile is among the most carnivorous of ants, Argentine ants from California occupied lower trophic positions. These results support the hypothesis that Argentine ants shift their diet after establishment as a result of resource depletion and increasing reliance on plant-based resources, especially honeydew-producing Hemiptera. Our results demonstrate the value of long-term and biregional data in uncovering ecological effects of invasions.

  4. A comprehensive dairy valorization model

    NARCIS (Netherlands)

    Banaszewska, A.; Cruijssen, F.C.A.M.; Vorst, van der J.G.A.J.; Claassen, G.D.H.; Kampman, J.L.

    2013-01-01

    Dairy processors face numerous challenges resulting from both unsteady dairy markets and some specific characteristics of dairy supply chains. To maintain a competitive position on the market, companies must look beyond standard solutions currently used in practice. This paper presents a comprehensi

  5. Silage Quality and Dairy Production

    Science.gov (United States)

    High quality silages are often the keystone of rations for dairy cows. Rations for dairy animals may contain 10 to 90%; therefore silage quality, which encompasses all silage characteristics that impact animal performance, is often crucial in meeting the nutrient requirements for dairy production. N...

  6. Digestibility of diets with glycerin for Nellore heifers in feedlot

    Directory of Open Access Journals (Sweden)

    Marisa Xavier Manço

    2012-12-01

    Full Text Available The research for not pollutants and renewable sources of energy, made the biodiesel is reused. But, its production generates the “Glycerin” (10% of biodiesel volume. This production is increasing and accumulating year by year, like other industrious by-products. With no law about discarding, scientists started to feed animals in different species with it. Rich in glycerol, it gives energy for animals and doesn't have other nutrients. It improves the alimentary conversion and does not change ruminal ambient or carcass production. For ruminants is used glycerin originated just from vegetables. This experiment aimed to discover what glycerin’s level can be used on diet. Made at the Unesp University of Campus of Jaboticabal, were used 24 heifers of Nellore in feedlot, weight of ± 265 kg in individuals stalls for 112 days. Were used three crossbreed cattle (Angus x Nellore castrated and cannulated, with ± 400 kg of weight for incubation. The “blond glycerin” used has 83% of glycerol. The proportion of Forage: Concentrate was 30:70. Corn silage was the forage. The concentrate was composed of: soy hulls, sunflower meal, urea and corn or corn more glycerin. All treatments had same percentages of protein and energy and were identified as “without glycerin” (G0, “with 10% of glycerin” (G10 and “20% of glycerin inclusion” (G20 in the dry matter of diet. Samples of food, leavings and excrements were collected. The collections of excrements were made at the superior part of them, without contact with the floor, at the moment of defecation for three consecutive days. Leavings and food were collected just before feeding. Bromatologics analyses were made according AOAC (1995, VAN SOEST and WINE (1967, HENDRIX (1993 and the digestion was made in autoclave (0,5 Kgf/cm2, 111ºC for 50 minutes, proceeding adapted of PELL and SCHOFIELD (1992. ADFi was used as indicator. Incubation was made according to CASALI et al. (2008 for 240 hours and

  7. Methods for early prediction of lactation flow in Holstein heifers

    Directory of Open Access Journals (Sweden)

    Vesna Gantner

    2010-12-01

    Full Text Available The aim of this research was to define methods for early prediction (based on I. milk control record of lactation flow in Holstein heifers as well as to choose optimal one in terms of prediction fit and application simplicity. Total of 304,569 daily yield records automatically recorded on a 1,136 first lactation Holstein cows, from March 2003 till August 2008., were included in analysis. According to the test date, calving date, the age at first calving, lactation stage when I. milk control occurred and to the average milk yield in first 25th, T1 (and 25th-45th, T2 lactation days, measuring monthcalving month-age-production-time-period subgroups were formed. The parameters of analysed nonlinear and linear methods were estimated for each defined subgroup. As models evaluation measures,adjusted coefficient of determination, and average and standard deviation of error were used. Considering obtained results, in terms of total variance explanation (R2 adj, the nonlinear Wood’s method showed superiority above the linear ones (Wilmink’s, Ali-Schaeffer’s and Guo-Swalve’s method in both time-period subgroups (T1 - 97.5 % of explained variability; T2 - 98.1 % of explained variability. Regarding the evaluation measures based on prediction error amount (eavg±eSD, the lowest average error of daily milk yield prediction (less than 0.005 kg/day, as well as of lactation milk yield prediction (less than 50 kg/lactation (T1 time-period subgroup and less than 30 kg/lactation (T2 time-period subgroup; were determined when Wood’s nonlinear prediction method were applied. Obtained results indicate that estimated Wood’s regression parameters could be used in routine work for early prediction of Holstein heifer’s lactation flow.

  8. Effects of residual feed intake and dam body weight on replacement heifer intake, efficiency, performance, and metabolic response.

    Science.gov (United States)

    Walker, R S; Martin, R M; Buttrey, B

    2015-07-01

    Thirty-eight Angus-based, crossbred, nulliparous beef heifers (BW = 280 ± 26.3 kg) sired by 2 Angus sires were used to determine if dam BW affected heifer performance, DMI, residual feed intake (RFI), and endocrine markers. Heifers were housed in individual pens (2.2 by 9.1 m) equipped with 2.2 m of bunk space and fed a diet (90.4% DM, 13.7% CP, 67.2% NDF, and 56.2% TDN) consisting of 87.2% bermudagrass hay and 12.8% liquid protein supplement for a 14-d adaption period and a 70-d feeding period. Individual daily feed intake was used to calculate RFI for each heifer, and heifer was the experimental unit. Two-day beginning and end BW were recorded and hip height was used to calculate frame score (FS). Heifer dams were assigned to a light (LIT; 544 ± 21.3 kg) or heavy (HEV; 621 ± 34.8 kg) BW group on the basis of mean BW at the beginning of their lactation period the previous year to determine differences in heifer offspring DMI and RFI. Based on heifer RFI ranking, heifers were classified as positive (POS; 0.34) or negative (NEG; –0.31) RFI and low (LOW; –0.45), medium (MED; 0.00), or high (HI; 0.49) RFI for analysis of BW, FS, BW gain, and DMI. There were no dam BW group × sire interactions (P > 0.10) for all independent variables. Beginning and end BW was greater (P 0.10) for heifers out of HEV compared with LIT BW dams; however, a sire effect existed (P 0.10) whereas DMI was greater (P = 0.03) among heifers in the POS compared with the NEG RFI group and greater (P = 0.01) among heifers in the MED and HI compared with LOW RFI group, respectively. Plasma insulin levels were greater (P = 0.03) in the NEG compared with the POS RFI heifers, and thyroxine (T4) levels were greater (P = 0.02) in the POS compared with the NEG RFI heifers. A positive relationship existed (P ≤ 0.05) between dam BW and heifer DMI (r = 0.42), beginning and end BW (r = 0.45 and 54), and FS (r = 0.58) and between RFI and d 70 triiodothyronine (r = 0.34), d 70 T4 (r = 0.35), and d 0 and

  9. [Mycobacterium bovis in wildlife of the dairy regions of Santa Fe (Argentina)].

    Science.gov (United States)

    Abdala, Alejandro A; Garbaccio, Sergio; Zumárraga, Martín; Tarabla, Héctor D

    2015-01-01

    Control eradication campaigns of bovine tuberculosis based on the «test and slaughter» approach were successful in many countries and regions; however, in some areas the infection persists and one of the main reasons is Mycobacterium bovis infection in wild life species. Argentina has applied the same approach since 1999, achieving progress in dairy cattle herds. Nonetheless, the wildlife role has never been investigated. The objective of this study was to determine if wildlife from the Santa Fe dairy area is infected with M. bovis. Wildlife species having a positive tuberculin skin test were captured in five dairy farms. Ninety five wildlife mammals were captured; M. bovis was recovered from 7 possums (Didelphys albiventris), from one fox (Lycolapex gimnocercus) and from one rat (Rattus norvegicus). None of the animals exhibited macroscopic lesions. The most frequently isolated M. bovis spoligotypes were types 34 (4 isolates) and 12 (3 isolates). Spoligotype 34 is the most frequently isolated type in Argentine cattle. The role of D. albiventris as spillover host of M. bovis is discussed in this study. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  10. Comparative leaf anatomy in argentine Galactia species Anatomía comparada de hoja en especies argentinas de Galactia

    OpenAIRE

    G. M. Tourn; M. T. Cosa; G. G. Roitman; Silva,M.P.

    2009-01-01

    A comparative study of anatomical characters of the leaves of argentine species of Genera Galactia was carried out in order to evaluate their potential value in Taxonomy. In Argentine 14 species and some varieties from Sections Odonia and Collaearia can be found. Section Odonia: G. benthamiana Mich., G. dubia DC., G. fiebrigiana Burkart var. correntina Burkart, G. glaucophylla Harms, G. gracillima Benth., G. latisiliqua Desv., G. longifolia (Jacq.) Benth., G. marginalis Benth., G. striata (Ja...

  11. Comparative leaf anatomy in argentine Galactia species Anatomía comparada de hoja en especies argentinas de Galactia

    OpenAIRE

    Tourn, G.M.; M. T. Cosa; G. G. Roitman; Silva,M.P.

    2009-01-01

    A comparative study of anatomical characters of the leaves of argentine species of Genera Galactia was carried out in order to evaluate their potential value in Taxonomy. In Argentine 14 species and some varieties from Sections Odonia and Collaearia can be found. Section Odonia: G. benthamiana Mich., G. dubia DC., G. fiebrigiana Burkart var. correntina Burkart, G. glaucophylla Harms, G. gracillima Benth., G. latisiliqua Desv., G. longifolia (Jacq.) Benth., G. marginalis Benth., G. striata (Ja...

  12. Argentine ant invasion associated with loblolly pines in the southeastern United States: minimal impacts but seasonally sustained.

    Science.gov (United States)

    Rowles, Alexei D; Silverman, Jules

    2010-08-01

    Invasive ants are notorious for directly displacing native ant species. Although such impacts are associated with Argentine ant invasions (Linepithema humile) worldwide, impacts within natural habitat are less widely reported, particularly those affecting arboreal ant communities. Argentine ants were detected in North Carolina mixed pine-hardwood forest for the first time but were localized on and around loblolly pines (Pinus taeda), probably because of association with honeydew-producing Hemiptera. We explored the potential impacts of L. humile on arboreal and ground-foraging native ant species by comparing interspersed loblolly pines invaded and uninvaded by Argentine ants. Impacts on native ants were assessed monthly over 1 yr by counting ants in foraging trails on pine trunks and in surrounding plots using a concentric arrangement of pitfall traps at 1, 2, and 3 m from the base of each tree. Of floristics and habitat variables, higher soil moisture in invaded plots was the only difference between plot types, increasing confidence that any ant community differences were caused by Argentine ants. Overall patterns of impact were weak. Composition differed significantly between Argentine ant invaded and uninvaded trunks and pitfalls but was driven only by the presence of Argentine ants rather than any resulting compositional change in native ant species. Native ant abundance and richness were similarly unaffected by L. humile. However, the abundance of individual ant species was more variable. Although numbers of the arboreal Crematogaster ashmeadi (Myrmicinae) declined on and around invaded pines, epigeic Aphaenogaster rudis (Myrmicinae) remained the most abundant species in all plots. Argentine ant densities peaked in late summer and fall, therefore overlapping with most native ants. Unexpected was their continued presence during even the coldest months. We provide evidence that Argentine ants can invade and persist in native North Carolina forests, probably

  13. Streptococcus agalactiae in the environment of bovine dairy herds--rewriting the textbooks?

    Science.gov (United States)

    Jørgensen, H J; Nordstoga, A B; Sviland, S; Zadoks, R N; Sølverød, L; Kvitle, B; Mørk, T

    2016-02-29

    Many free-stall bovine dairy herds in Norway fail to eradicate Streptococcus agalactiae despite long-term control measures. In a longitudinal study of 4 free-stall herds with automatic milking systems (AMS), milk and extramammary sites were sampled 4 times with 1-2 month intervals. Composite milk, rectal- and vaginal swabs were collected from dairy cows; rectal swabs from heifers and young stock; rectal- and tonsillar swabs from calves; and environmental swabs from the AMS, the floors, cow beds, watering and feeding equipment. A cross sectional study of 37 herds was also conducted, with 1 visit for environmental sampling. Fifteen of the herds were known to be infected with S. agalactiae while the remaining 22 had not had evidence of S. agalactiae mastitis in the preceding 2 years. All samples were cultured for S. agalactiae, and selected isolates (n=54) from positive herds were genotyped by Multi Locus Sequence Typing (MLST). Results show that the bovine gastrointestinal tract and the dairy cow environment are reservoirs of S. agalactiae, and point to the existence of 2 transmission cycles; a contagious transmission cycle via the milking machine and an oro-fecal transmission cycle, with drinking water as the most likely vehicle for transmission. Ten sequence types were identified, and results suggest that strains differ in their ability to survive in the environment and transmit within dairy herds. Measures to eradicate S. agalactiae from bovine dairy herds should take into account the extra-mammary reservoirs and the potential for environmental transmission of this supposedly exclusively contagious pathogen.

  14. Dairy nutrition management: Assessing a comprehensive continuing education program for veterinary practitioners.

    Science.gov (United States)

    Schuenemann, G M; Eastridge, M L; Weiss, W P; Workman, J D; Bas, S; Rajala-Schultz, P

    2011-05-01

    The purpose of this study was to assess the effectiveness of a team-based educational program designed to enhance the flow of applied, research-based, nutrition information to dairy veterinarians. A comprehensive dairy cattle nutrition curriculum was developed and participants from 11 veterinary practices located in 5 states (IN, NY, PA, NM, and OH), serving an estimated 186,150 dairy cattle in 469 herds, attended the 2 advanced nutrition modules (∼2.5 d each and ∼40 h of learning) held in 2009. Nutrients, feeding transition cows, calves, and heifers, dry matter intake, feed storage, metabolic diseases, evaluating cows (scoring body condition, manure, and lameness), metabolic blood profiles, and feeding behavior were discussed. Educational materials were delivered through in-class lectures, followed by case-based learning and group discussions. A farm visit and out-of-class assignments were also implemented. Attendees were assessed using pre- and post-tests of knowledge to determine the level of knowledge gained in both nutrition modules. Participants evaluated the program and provided feedback at the conclusion of each module. Veterinarians (100%) reported that the overall program, presentations, and discussions were useful. Attendees found the presented information relevant for their work (agree=60% and strongly agree=40%) and of great immediate use to them (neutral=6.5%, agree=56%, and strongly agree=37.5%). The presented materials and the implemented educational delivery methods substantially increased the knowledge level of the attendees (16.9% points increase from pre-test to post-test scores). Importance of feed particle size, ration evaluation, interpreting feed analysis, balancing carbohydrate components, and metabolic profiling in fresh cows were listed as learned concepts that participants could apply in their practices. Results suggested that both nutrition modules were relevant and effective, offering new information with immediate field

  15. Diversity of Eimeria spp. in dairy cattle of Guwahati, Assam, India

    Directory of Open Access Journals (Sweden)

    M. Das

    2015-08-01

    Full Text Available Aim: To determine the prevalence and diversity of Eimeria spp. in dairy cattle present in and around Guwahati, Kamrup district, Assam, India. Materials and Methods: A total of 2339 fecal samples of calves (535, heifer (641 and adult (1163 cattle were screened for 1 year present in and around Guwahati, Assam for detection of Eimeria oocysts by flotation techniques. Sporulation of the oocyst was done in 2.5% potassium dichromate solution for identification of the Eimeria species. Results: Examination of fecal samples revealed an overall prevalence of 11.97% Eimeria infection in dairy cattle of Guwahati, Assam. Age-wise, 33.2%, 45.4%, and 21.4% infections were recorded in calves (3 years cattle, respectively. Season-wise, infection was recorded highest during post-monsoon (16.29%, followed by monsoon (15%, winter (9.44%, and pre-monsoon (7.49% season. Seven species of Eimeria were recorded viz. Eimeria bovis, Eimeria zuernii, Eimeria subspherica, Eimeria bukidnonensis, Eimeria auburnensis, Eimeria ellipsoidalis and Eimeria alabamensis. The oocyst count per gram of feces ranged from 50 to 1500 in infected cattle. Conclusion: This study indicates that there is the prevalence of seven species of Eimeria in dairy cattle of Guwahati, Assam and mostly prevalent during the post-monsoon season.

  16. Phenotypic and genotypic analysis of age at first calving in Iranian Holstein dairy cows

    Directory of Open Access Journals (Sweden)

    Atefeh Seyeddokht

    2015-12-01

    Full Text Available Introduction: Age at first calving (AFC has an important effect on profitability and reproductive management of dairy cattle. Every month increase in AFC beyond 24 months increases the cost of production. The time between birth and first calving represents a period in which replacement heifers are not generating income. Instead this rearing period requires considerable capital expenditures including feed, housing, and veterinary expenses. These expenses constitute 15% to 20% of the total expenses related to milk production. A basic approach to reduce this cost is to decrease the time between birth and her first freshening. Worldwide recommendations for one particular AFC might be an incorrect management goal for all of the cattle on all of the farms, since the recommendation might not represent the management goals and/or capabilities of a particular production system or farm. We realize that each dairy has its own set of unique management and environmental conditions, which makes a universal AFC and BW after first calving, a difficult goal to achieve. The AFC has a profound influence on the total cost of raising dairy replacements in which older calving heifers are more expensive to raise than younger ones. Materials and methods: A total of 19499 calving records belonged to 96 herd from 1996 to 2008 were used to estimate genetic components and genetic trend for age at first calving in Holstein dairy cows of Iran. Data were analyzed using a univariate model and Wombat software. Linear regression of estimated breeding values on calving year was used to estimate genetic trend. Results and Discussion: Estimated genetic trend was positive for some years and was negative for others and showed that reducing age at first calving has not been considered in the selection strategies; however, the phenotypic trend was decreased. The age at first calving for Yazd, Markazi, and southern Khorasan provinces were the highest and for Kermanshah, East Azarbayjan

  17. Timed artificial insemination should be performed early when used norgestomet ear implants are applied for synchronizing ovulation in beef heifers.

    Science.gov (United States)

    Sá Filho, M F; Penteado, L; Siqueira, G R; Soares, J G; Mendanha, M F; Macedo, G G; Baruselli, P S

    2013-10-01

    The present study evaluated the effect of the type of norgestomet ear implant (new vs. used) on the ovarian follicular response (experiment 1) and pregnancy per artificial insemination (AI) (P/AI; experiment 2) of beef heifers subjected to an estradiol plus progestin timed artificial insemination (TAI) program. In experiment 1, 57 cyclic beef heifers were randomly assigned to one of two groups according to the type (new or previously used for 9 days) of norgestomet ear (NORG) implant. At the time of NORG implant insertion, the heifers were treated with 2 mg of intramuscular estradiol benzoate. Eight days later, the NORG implants were removed, and the heifers received an intramuscular administration of 150 μg of d-cloprostenol, 300 IU of equine chorionic gonadotropin, and 0.5 mg of estradiol cypionate. The heifers had their ovaries scanned every 12 hours from the time of NORG implant removal to 96 hours after verifying the occurrence and timing of ovulation. No difference (P = 0.89) was observed in the ovulation rates between the two treatments (new = 80.0%; 24/30 vs. used = 81.5%; 22/27). However, the heifers treated with a used NORG implant had (P = 0.04) higher proportion (36.4%; 8/22) of early ovulation (between 36 and 48 hours after NORG implant removal) compared with the heifers treated with a new NORG implant (8.3%; 2/24). In experiment 2, at the beginning of the synchronization protocol, 416 beef heifers were randomly assigned into two groups, as described in the experiment 1. Two days after the NORG implant removal, the heifers were reassigned to be inseminated at 48 or 54 hours after NORG implant removal. There was an interaction (P = 0.03) between the type of NORG implant and the timing of TAI on P/AI. The timing of insemination only had an effect (P = 0.02) on the P/AI when the heifers were treated with a used NORG implant [(TAI 54 hours = 41.9% (44/105) vs. TAI 48 hours = 58.6% (58/99)]. In conclusion, beef heifers synchronized with a used NORG implant

  18. Forage and breed effects on behavior and temperament of pregnant beef heifers

    Science.gov (United States)

    Integration of behavioral observations with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems. Brahman-influenced (BR; n=64) and Gelbvieh x Angus (GA; n=64) heifers consumed either toxic endophyte-infected tall fescue (E+)...

  19. Altered endometrial immune gene expression in beef heifers with retarded embryos.

    Science.gov (United States)

    Beltman, M E; Forde, N; Lonergan, P; Crowe, M A

    2013-01-01

    The aim of the present study was to compare endometrial gene expression profiles in a group of beef heifers yielding viable or retarded embryos on Day 7 after oestrus as a means of potentially explaining differences in embryo survival rates. Heifers were classified as either: (1) viable, when the embryo collected on Day 7 after oestrus was at the correct developmental stage (i.e. morula/early blastocyst); or (2) retarded, when the embryo was arrested at the 2-16-cell stage. The focus of the present study was on genes that were associated with either the pro- or anti-inflammatory immune response. Endometrial gene expression was determined using quantitative real-time polymerase chain reaction analysis. Expression of the β-defensin (DEFB1), interferon (IFN)-α (IFNA), IFN-γ (IFNG), interleukin (IL)-6 (IL6), IL-10 (IL10), forkhead box P3 (FOXP3) and natural cytotoxicity triggering receptor 1 (NCR1) genes was lower in endometria from viable than retarded heifers. Expression of the nuclear factor of kappa light polypeptide gene enhancer in B cells 1 (NKFB1), transforming growth factor (TGF)-β (TGFB), IFN-γ-inducible protein 16 (IFI16) and IL-21 (IL21) genes was higher in viable than retarded heifers. We propose that small disturbances in the expression of immune genes in the endometrium on Day 7 after oestrus can have detrimental effects on embryo survival.

  20. Qualitative characteristics of meat from confined crossbred heifers fed with lipid sources

    Directory of Open Access Journals (Sweden)

    Giovani Fiorentini

    2012-10-01

    Full Text Available Lipids have been used in ruminant feed to replace high amounts of grain for increasing the diet energy density, performance and meat quality. This study evaluated the qualitative characteristics of meat from feedlot heifers fed with sources of lipid supplements. Twenty-one crossbred heifers (1/4Nelore × 1/4Santa Gertrudis × 1/2Braunvieh were used. Each heifer received 60 % forage with a base of corn silage and 40 % concentrate, resulting in 5.8 % lipid content in the total diet. The following sources of lipids were used: soybeans, protected fat and soybean oil. There were no differences on physical characteristics of meat samples from heifers fed with the lipid sources. Soybeans increased the concentration of linoleic acid, content of polyunsaturated fatty acid and activity of the Δ9-desaturase C16 enzyme in the Longissimus muscle. The use of soybean oil in the diet increased the oleic acid, monounsaturated fatty acid, total cis- and trans-fatty acids (C18:0 and the activity of the Δ9-desaturase C16 enzyme in the subcutaneous fat. Diets with soybean grain had greater deposition of linoleic and linolenic acids than diets with fat protected and greater presence of these essential fatty acids are associated to a better composition and meat quality.

  1. Infestation by Rhipicephalus (Boophilus microplus in heifers from different genetics groups

    Directory of Open Access Journals (Sweden)

    Adilson Marini

    2010-01-01

    Full Text Available An assessment of the infestation of ticks Rhipicephalus (Boophilus microplus in 59 heifers of three genetic groups was run: Nellore, Guzerá and ½ Angus x ½ Nellore, belonging to the roster APTA Regional Andradina / SP. Every 28 days held the count of ticks, where the left side of the animal, with evaluation of only engorged females with more than 4.5 mm in the period from June 2007 to May 2008. The genetic group (P 0.05. The count of ticks was higher in the rainy season (4.32 ± 5.20 in comparison with the dry season (3.74 ± 5.54. Despite the higher counts of ticks during the experimental period, in heifers ½ Angus x ½ Nellore, this genetic group obtained the highest average daily weight gain (0.57 kg/day. Heifers and bulls Nellore and Guzerá were not statistically different in relation to daily weight gain, with averages of 0.37 and 0.40kg/day, respectively. ½ Angus heifers genetic group cattle have a higher infestation by ticks.

  2. In Utero Exposure to Lipopolysaccharide Alters the Postnatal Acute Phase Response in Beef Heifers

    Science.gov (United States)

    This study was designed to determine the potential effect of prenatal lipopolysaccharide (LPS) exposure on the postnatal acute phase response (APR) to an LPS challenge in heifers. Pregnant crossbred cows (n = 50) were separated into prenatal immune stimulation (PIS; n = 25; administered 0.1 microgr...

  3. Effect of increased systemic concentrations of urea nitrogen in crossbred heifers on in vitro fertilization (IVF)

    Science.gov (United States)

    Elevated levels of dietary N and hence systemic concentrations of urea-N have been shown to have a deleterious effect on reproductive processes. The objective of this study was to determine the effect of feeding pubertal crossbred heifers diets with moderate (M-N; 64.8% corn silage, 30.0% alfalfa h...

  4. The Reference Intervals of Hair Trace Element Content in Hereford Cows and Heifers (Bos taurus).

    Science.gov (United States)

    Miroshnikov, Sergey A; Zavyalov, Oleg A; Frolov, Alexey N; Bolodurina, Irina P; Kalashnikov, Valery V; Grabeklis, Andrei R; Tinkov, Alexey A; Skalny, Anatoly V

    2017-03-17

    The objective of the present study was to assess hair trace element content in Hereford heifers and cows (Bos taurus) living in South Ural region and calculate the site-specific reference intervals. Hair trace element content in 150 cows and heifers farmed in the Southern Urals of Russia was assessed using inductively coupled plasma mass-spectrometry. Dietary trace element content corresponded to the adequate values as estimated by recommendations of USSR State Agriculture Committee and U.S. National Research Council. Comparative analysis demonstrated that heifers are characterized by significantly higher hair Se (3-fold), Hg (4-fold), and Sn (46%) content, whereas cows had significantly higher levels of hair Co (56%), I (33%), Si (2-fold), V (27%), B (55%), Cd (19%), Pb (47%), and Sr (23%). At the same time, no significant group difference in hair Cr, Cu, Fe, Li, Mn, Zn, As, and Ni was detected between Hereford cows and heifers. The reference intervals and 90% confidence intervals for the lower and upper limits were calculated in agreement with the American Society for Veterinary Clinical Pathology Quality Assurance and Laboratory Standard Guidelines.

  5. Uterine environment and pregnancy rate of heifers with elevated plasma urea nitrogen.

    Science.gov (United States)

    Amundson, Olivia L; Larimore, Erin L; McNeel, Anthony K; Chase, Chad C; Cushman, Robert A; Freetly, Harvey C; Perry, George A

    2016-10-01

    Diets high in protein are associated with lower reproductive performance and changes in the uterine environment. The objective of this study was to determine the effect of elevated systemic concentrations of urea nitrogen on the uterine environment and pregnancy success in beef heifers. Heifers (n=150) were matched by breed, age, and body weight then randomly assigned to one of two dietary treatments: 1) Control (10% CP) or 2) High protein (14% CP) over three replicates (n=40/replicate). Estrus was synchronized with an injection of PGF2α. Uterine pH, plasma urea nitrogen (PUN), ammonia, and glucose concentrations were determined on d 7 of the estrous cycle. Pregnancy status was determined by ultrasonography 30 d following the breeding season. In vitro fertilization was performed on heifers precluded from uterine analysis (n=15/diet) to determine the effect of a High Protein diet on oocyte quality. Plasma urea concentrations were greater in the High Protein diet compared to Control (P0.40) on the number of oocytes collected, number of oocytes cleaved, amount of blastocysts, percentage of oocytes cleaved and percentage of blastocysts present. In summary, high nitrogen diets increased PUN concentrations in heifers; however, there were no deleterious effects on reproduction.

  6. Zilpaterol hydrochloride affects cellular muscle metabolism and lipid components of ten different muscles in feedlot heifers

    Science.gov (United States)

    This study determined if zilpaterol hydrochloride (ZH) altered muscle metabolism and lipid components of ten muscles. Crossbred heifers were either supplemented with ZH (n = 9) or not (Control; n = 10). Muscle tissue was collected (adductor femoris, biceps femoris, gluteus medius, infraspinatus, lat...

  7. Influence of pregnancy on body weight, ruminal characteristics, and visceral organ mass in beef heifers.

    Science.gov (United States)

    Scheaffer, A N; Caton, J S; Bauer, M L; Reynolds, L P

    2001-09-01

    Crossbred heifers (initially 24 mo, approximate age and 378 +/- 32.1 kg BW) were used to evaluate the influence of pregnancy and advancing gestation on DMI, BW, carcass weight, ruminal characteristics, and visceral organ mass. Heifers (naturally serviced (n = 22; nonpregnant controls, n = 17), were grouped in common pens. Heifers were provided corn silage and hay-based diets formulated to provide 0.45 kg of ADG. Treatments were pregnancy and nonpregnancy; pregnant and nonpregnant heifers were slaughtered on d 40, 120, 200, and 270. Live weight at slaughter and BW change throughout the trial were not influenced by pregnancy (P > 0.1). Carcass weight per unit of BW was decreased due to pregnancy (P 0.1) at any of the slaughter periods. Heart mass responded differently when nonpregnant and pregnant were analyzed over time and an interaction was detected as slaughter period advanced (P 0.1). Data indicate that ruminal fill is altered by pregnancy but visceral organ mass is not greatly changed by treatment.

  8. Age at puberty in beef heifers: Criollo cattle versus british crossbred cattle.

    Science.gov (United States)

    Age at puberty is an important factor in estimating the potential productivity of the bovine female. A study was conducted at the ARS-USDA Jornada Experimental Range in 2006 and 2007 to compare onset of puberty, BW, and serum insulin in Criollo and Angus-Hereford crossbred heifers. In 2006, 7 Crioll...

  9. Effect of antral follicle count in beef heifers on in vitro fertilization/production

    Science.gov (United States)

    Our objective has been to compare the in vitro fertilization (IVF) and production (IVP) of embryos from low and high antral follicle count (AFC) heifers. This is the 4th year of the study with years 1 to 3 reported individually. For this report, we add data for the 4th year and present a combined an...

  10. 7 CFR 1150.112 - Dairy products.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Dairy products. 1150.112 Section 1150.112 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PROMOTION PROGRAM Dairy Promotion and Research Order Definitions § 1150.112 Dairy products. Dairy products means products manufactured for...

  11. 7 CFR 1170.4 - Dairy products.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Dairy products. 1170.4 Section 1170.4 Agriculture... and Orders; Milk), DEPARTMENT OF AGRICULTURE DAIRY PRODUCT MANDATORY REPORTING § 1170.4 Dairy products. Dairy Products means: (a) Manufactured dairy products that are used by the Secretary to...

  12. Effect of Aegle marmelos and Murraya koenigii in treatment of delayed pubertal buffaloes heifers

    Directory of Open Access Journals (Sweden)

    Mohan M. Baitule

    2016-12-01

    Full Text Available Aim: This study aims to study the estrus induction, ovulation, and conception rate of delayed puberty in buffaloes heifers by feeding a herbal plants Aegle marmelos (bael/bili/bhel leaf and Murraya koenigii (Curry leaf. Materials and Methods: Totally, 24 buffalo heifers with delayed puberty were selected for the present study and divided randomly in four equal groups (n=6. Before experiment, all animals were dewormed with albendazole at 10 mg/kg body weight to prevent them from the stress of parasitism. In the present experiment, four group taken and Group I (n=6 treated with A. marmelos, Group II (n=6 treated with M. koenigii, Group III (n=6 treated with mixture of A. marmelos and M. koenigii and fed for 9 days. Group IV (n=6 considered as control and fed with concentrate only. The blood samples were collected from all the animals on day 0 (before treatment, 4, 9 (during treatment, on the day of estrus and day 8 after the onset of estrus. The 10 ml blood was collected from the jugular vein of all the experimental animals for estimation of serum calcium, inorganic phosphorus, and progesterone (P4. The estrus response, ovulation, conception rate along with serum calcium, inorganic phosphorus, and progesterone level were determined by the standard protocol. Results: From Group III 4 heifers, from Group II 3 heifers, and from Group I and IV (Control 2 heifers each, exhibited the estrus. The estrus response was recorded as 33.33%, 50.00%, 75.00%, and 33.33% in Group I, Group II, Group III, and Group IV, respectively. In treatment Group III, serum calcium found significantly more (p<0.05 on day 8 post-estrus as compared to other groups at a similar interval. Inorganic phosphorus and progesterone show no significant difference between groups. The ovulation and conception rates are comparatively better in Group III (75% buffalo heifers than other groups. Conclusion: Herbal supplementation of A. marmelos and M. koenigii in combination, as well as M

  13. Cell mediated immune responses in the placenta following challenge of vaccinated pregnant heifers with Neospora caninum.

    Science.gov (United States)

    Hecker, Y P; Cantón, G; Regidor-Cerrillo, J; Chianini, F; Morrell, E; Lischinsky, L; Ortega-Mora, L M; Innes, E A; Odeón, A; Campero, C M; Moore, D P

    2015-12-15

    The aim of the present study was to investigate and correlate the cell-mediated immune response and pathological changes at the maternal-fetal interface of Neospora-challenged pregnant cattle previously immunized with live and inactivated experimental vaccines. Pregnant heifers naïve to Neospora caninum were divided in 5 groups of 4 animals, each one immunized before mating: Group A heifers were intravenously (iv) immunized with 6.25 × 10(7) live tachyzoites of the NC-6 strain; group B heifers were immunized twice subcutaneously (sc) 3 weeks apart with native antigen extract of the NC-6 strain formulated with ISCOMs; group C heifers were sc immunized twice 3 weeks apart with three recombinant proteins (rNcSAG1, rNcHSP20, rNcGRA7) of the NC-1 strain formulated with ISCOMs; group D heifers were sc injected with sterile phosphate-buffered saline (PBS) and group E heifers received sc ISCOM-matrix (ISCOMs without antigen). All groups were iv-challenged with 4.7 × 10(7) NC-1 tachyzoites at 70 days of gestation. Heifers were culled at day 104 of gestation and placentomes were examined to evaluate lesions and local cellular immune responses using histopathology, immunohistochemistry and real time-PCR. Immunohistochemistry was performed using bovine leucocyte specific antibodies. Cytokine expression and levels (IFN-γ, IL-4, IL-10, IL-12 and TNF-α) were measured using real-time reverse transcription-PCR and ELISA, respectively. Minimal inflammation was observed in group A placentomes; while placentomes from group B, C, D and E had moderate to severe infiltration with CD3(+), CD4(+), γδ-T cells, CD8(+) cells and macrophages being more numerous in groups B and E placentomes, when compared with groups C and D (P<0.001). Cytokine levels were significantly increased in the caruncles of animals of groups B and C in comparison with the other animal groups (P < 0.001). The results from this study showed that the strongest cellular immune responses were observed in the

  14. Dairy chemistry and physics

    NARCIS (Netherlands)

    Walstra, P.; Jenness, R.

    1984-01-01

    Milk and products made from it affect the lives of a large proportion of the world’s population. Many dairy products are consumed at times and in places far removed from the point at which the milk was produced. This is made possible by the chemical and physical treatments and fractionations applied

  15. Dairy Sector Profit Squeeze

    Institute of Scientific and Technical Information of China (English)

    WANG PEI

    2006-01-01

    @@ Like any other industries in China,the potential in the dairy industry is huge but competition is tough,The big players such as Mengniu and Yili are happy to stay engaged in a price war that has raged for the last year,seemingly not affected by rising raw material prices.

  16. Dairy cow disability weights.

    Science.gov (United States)

    McConnel, Craig S; McNeil, Ashleigh A; Hadrich, Joleen C; Lombard, Jason E; Garry, Franklyn B; Heller, Jane

    2017-08-01

    Over the past 175 years, data related to human disease and death have progressed to a summary measure of population health, the Disability-Adjusted Life Year (DALY). As dairies have intensified there has been no equivalent measure of the impact of disease on the productive life and well-being of animals. The development of a disease-adjusted metric requires a consistent set of disability weights that reflect the relative severity of important diseases. The objective of this study was to use an international survey of dairy authorities to derive disability weights for primary disease categories recorded on dairies. National and international dairy health and management authorities were contacted through professional organizations, dairy industry publications and conferences, and industry contacts. Estimates of minimum, most likely, and maximum disability weights were derived for 12 common dairy cow diseases. Survey participants were asked to estimate the impact of each disease on overall health and milk production. Diseases were classified from 1 (minimal adverse effects) to 10 (death). The data was modelled using BetaPERT distributions to demonstrate the variation in these dynamic disease processes, and to identify the most likely aggregated disability weights for each disease classification. A single disability weight was assigned to each disease using the average of the combined medians for the minimum, most likely, and maximum severity scores. A total of 96 respondents provided estimates of disability weights. The final disability weight values resulted in the following order from least to most severe: retained placenta, diarrhea, ketosis, metritis, mastitis, milk fever, lame (hoof only), calving trauma, left displaced abomasum, pneumonia, musculoskeletal injury (leg, hip, back), and right displaced abomasum. The peaks of the probability density functions indicated that for certain disease states such as retained placenta there was a relatively narrow range of

  17. Culling decisions of dairy farmers during a 3-year Salmonella control study

    DEFF Research Database (Denmark)

    Nielsen, Liza Rosenbaum; Dohoo, I.

    2011-01-01

    with at least one recent moderately high ELISA result (flagged as “yellow”) on the lists. Risk management included, e.g. culling or separation of the cows at calving. We analysed culling decisions using two models. For heifers a hierarchical multivariable logistic model with herd as random effect evaluated...... animals into risk groups. These risk groups and all individual ELISA-results were communicated to the farmers as colour-coded lists four to six times per year. Farmers were advised to manage the risk of Salmonella transmission from cattle with repeatedly high ELISA results (flagged as “red”) or cows...... Dublin which is the most prevalent and most persistent serotype in the Danish cattle population. A field study in 10 dairy herds with persistent Salmonella infections was carried out over three years to gain experience with control procedures including risk assessment, targeted control actions and test...

  18. Extended lactations may improve cow health, productivity and reduce greenhouse gas emissions from organic dairy production

    DEFF Research Database (Denmark)

    Lehmann, Jesper Overgård; Mogensen, Lisbeth; Kristensen, Troels

    2014-01-01

    The concept of extended lactation is a break with the tradition of getting one calf per cow per year that should improve cow health, increase productivity and reduce greenhouse gas (GHG) emission per kg milk produced in high-yield organic dairy herds. These effects are achieved through fewer...... calvings per year and hence a production of fewer replacement heifers, which, in combination with fewer days dry per cow per year, will reduce the annual herd requirement for feed. Total herd feed use is a major determinant of GHG emission at farm gate. However, these effects also rely on the assumption...... of an unchanged milk production per feeding day (days lactating plus days dry) when changing from lactations of traditional length to extended lactations. Thus, milk yield per feeding day becomes a primary determinant of the success of using extended lactations at farm level. Cows undergoing an extended lactation...

  19. Genetic gain in dairy cattle populations is increased using sexed semen in commercial herds

    DEFF Research Database (Denmark)

    Sørensen, Morten Kargo; Andersen, Jakob Voergaard; Pedersen, Louise Dybdahl

    2011-01-01

    with 100 cows each. Each year 50 young bulls (YB), 10 active sires and 215 BD were selected on best linear unbiased prediction estimated breeding values by truncation selection across the simulated population, and the YB were tested within the population. Use of sexed semen alone gave a positive increase......Using stochastic simulation, the effect of using sexed semen to cow dams (CD) in a dairy cattle breeding scheme, with or without use of multiple ovulation and embryo transfer (MOET) to bull dams (BD), on annual genetic gain at the population level was examined. Three levels of sexed semen were...... combined with three levels of MOET: no sexed semen, sexed semen to the best CD and sexed semen to all heifers, combined with no MOET, MOET on all BD and MOET randomly on 20% of the BD. In total, nine scenarios were compared. The simulated population was monitored for 30 years and included 450 herds...

  20. EFFECT OF GnRH AND PHOSPHORUS IN DELAYED PUBERTAL SURTI BUFFALO HEIFERS

    Directory of Open Access Journals (Sweden)

    H.B. Dhamsaniya

    2016-06-01

    Full Text Available The study was conducted on eighteen delayed pubertal Surti buffalo heifers, divided into three equal groups (6 in each to evaluate the efficacy of GnRH alone and in combination of phosphorus. The buffalo heifers in Group-I and Group-II were treated with Buserelin acetate (5 ml, IM. Buffalo heifers in Group-II also received additional injection of Toldimphos sodium (10 ml, IM at 3 day interval for 4 times, while buffalo heifers in Group-III served as control. The percentage of induced estrus was highest (83.33% in each treated groups as compared to control group (50%. The mean estrus induction intervals were significantly (P<0.05 shorter in Group-I (20.20 ± 2.18 days and Group-II (18.80 ± 2.32 days as compared to control group (30.24 ± 0.81 days. The conception rate at induced estrus was highest in Group-II (50% followed by Group-I (33.33%. The plasma progesterone levels being significantly lowest on the day of estrus (less than 0.5 ng/ml as compared to pre-treatment days in all groups. The mean total protein and triglycerides levels were differed significantly between the groups on the day of estrus and being significantly higher in Group-II as compared to Group-I and III on that day. A significantly higher level of cholesterol in both treatment groups as compared to the control group during different intervals and also being higher on the day of estrus as compared to pre-treatment days. The mean plasma glucose levels were differed nonsignificantly between and within the treatment and control groups. It is concluded that estrus can be successfully induced in delayed pubertal heifers with the use of GnRH alone and in combination with phosphorus.

  1. Effects of creep feeding and monensin on reproductive performance and lactation of beef heifers.

    Science.gov (United States)

    Hixon, D L; Fahey, G C; Kesler, D J; Neumann, A L

    1982-09-01

    A 23 factorial arrangement of treatments was utilized to determine the effect of breed, creep feeding and monensin on subsequent reproductive performance and lactation of 32 primiparous heifers. One-half of each breed (Angus and Hereford) group had access to creep feed (2.67 Mcal metabolizable energy/kg) while nursing their dams. Approximately 40 d before breeding through 120 d of lactation, all heifers were fed a suboptimal energy diet and 50% of each breed and creep group received 200 mg monensin/head daily. Estrus was synchronized with a progestogen. Volatile fatty acids (VFA) were determined periodically throughout the monensin-feeding portion of the experiment. Twenty-four hour milk production, percentage butterfat and percentage solids-not-fat were determined at 60 and 120 d postpartum. Weaning weights (adjusted to 205 d and for age of dam) of the original heifers were heavier (P less than .05) for those that were creep fed compared with those not creep fed (219 vs 202 kg). Monensin-supplemented females gained significantly more weight from the initiation of treatment to immediately postcalving and gave birth to heavier calves (P less than .05) even though they received comparable amounts of dietary energy as those that did not receive monensin. The energy stressed, monensin-supplemented first-calf heifers exhibited a shorter postpartum interval (P less than .05) to first estrus than did those that did not receive monensin (55.7 vs 69.1 d, respectively). First-calf heifers that had been creep fed while nursing their dams had a lower (P less than .05) daily milk yield at 120 d post-partum than those that did not have access to creep feed. No detrimental effects were observed due to long-term monensin supplementation.

  2. Effects of forage-to-concentrate ratio and dietary fiber manipulation on gas emissions and olfactometry from manure of Holstein heifers.

    Science.gov (United States)

    Lascano, G J; Heinrichs, A J; Gary, R R; Topper, P A; Brandt, R C; Adviento-Borbe, A; Fabian, E E

    2015-03-01

    The objective of this experiment was to determine the effects of differing ratios of forage to concentrate (F:C) and fiber levels on odor and gas emissions from manure. Eight Holstein dairy heifers (362.45±4.53 d of age and 335.6±7.41 kg of body weight) were randomly assigned to a split-plot, 4×4 Latin square design (21-d periods) with F:C as the whole plot (20 or 80% forage) and fiber level as sub-plot (0, 20, 40, or 60% inclusion of corn stover). Gas concentration was determined using an infrared photoacoustic analyzer over a 24-h period using a steady-state flux chamber setup. Odorous air samples were collected from chamber headspace and evaluated by 6 human assessors using a forced-choice dynamic olfactometry technique. Emissions of CO2 were greater for the low than high concentrate diets, and no differences were observed for NH3 and CH4 emissions between F:C. Although F:C had no effect on NH3 emissions, as dietary fiber increased, a linear interaction with opposite effects was found for high and low concentrate diets. Nitrous oxide emissions were below minimum detectable levels. Neither F:C nor neutral detergent fiber level affected odor intensity. Odor emissions were successfully assessed, and manipulation of dietary fiber has the potential to influence CH4 and NH3 emissions.

  3. Pharmacokinetics of flunixin in mature heifers following multiple intravenous administration.

    Science.gov (United States)

    Jaroszewski, J; Jedziniak, P; Markiewicz, W; Grabowski, T; Chrostowska, M; Szprengier-Juszkiewicz, T

    2008-01-01

    The pharmacokinetics of flunixin meglumine was determined after its multiple (altogether 4 doses at 24-hours intervals) intravenous administration at a dose of 2.2 mg/kg body weight in six mature clinically healthy heifers. Plasma flunixin and its metabolite 5-hydroxyflunixin concentrations were analyzed with high-pressure liquid chromatography using an assay with a lower limit detection of 0.03 microg/ml for both substances. Plasma concentrations versus time curves were described by a two compartment open model. Mean plasma flunixin concentrations were similar on day 1 and 4, and than rapidly decreased (within 2 hours) from initial concentrations higher than 10 microg/ml to the concentrations lower than 1 microg/ml. The distribution phase of flunixin was short (t0.5 alpha = 0.29 +/- 0.16 and 0.18 +/- 0.04 on day 1 and 4, respectively) and the elimination phase was more prolonged (t0.5 beta = 3.30 +/- 0.60 and 3.26 +/- 0.22 on day 1 and 4, respectively). The mean residence time of flunixin was similar on day 1 (1.83 +/- 0.83) and 4 (1.88 +/- 0.46), and for 5-hydroxyflunixin this parameter was insignificantly (P > 0.05) higher on day 1 (5.49 +/- 2.22) as compared to that found on day 4 (3.99 +/- 2.17). The clearance of flunixin was similar on both examined days (0.23 +/- 0.12 on day 1 and 0.31 +/- 0.15 on day 4), and for 5-hydroxyflunixin was insignificantly (P > 0.05) lower on day 1 (2.37 +/- 1.21) as compared to that determined on day 4 (3.23 +/- 1.06). Our data indicate that multiple administration of flunixin did not alter significantly the parent drug and its metabolite concentrations in plasma, however may cause some small changes in pharmacokinetic parameters.

  4. Distribution of Fasciola hepatica in Swedish dairy cattle and associations with pasture management factors

    Directory of Open Access Journals (Sweden)

    Adam Novobilský

    2015-03-01

    Full Text Available The geographic distribution of Fasciola hepatica infection in relation to management routines was studied in Swedish dairy herds by testing for F. hepatica antibodies with the enzyme-linked immunosorbent assay (ELISA. In addition, all farmers were sent a questionnaire asking for information about type of production, management routines and historical record of F. hepatica at slaughter. A total of 176 farmers (41% responded to the questionnaire. A total of 426 bulk tank milk (BTM samples were randomly selected from the period September to October 2012 representing approximately 10% of all herds in Sweden. The overall seroprevalence was 25% (n = 107; 95% confidence interval = 21-29% with a concentration of herds located in south-western Sweden. Among the seropositive herds, 31 (29% had antibody levels indicating production loss. There were no significant differences in seropositivity between organic and conventional herds or due to pasture management routines. The length of grazing period, which increased the risk for heifers, was found to be the most influential factor. A discrepancy was noted between reported F. hepatica presence at meat inspection and herds that were seropositive based on BTM-ELISA results. Although the largest proportion of seropositive BTM samples (80% came from herds where liver fluke presence had been observed at meat inspection after slaughter, seropositive BTM samples were also diagnosed in five herds (17% with no remarks at slaughter. In conclusion, F. hepatica is a common parasite in Swedish dairy herds and the month of heifer turn-out and the grazing period length were the most influential factors observed.

  5. Feed and manure use in low-N-input and high-N-input dairy cattle production systems

    Science.gov (United States)

    Powell, J. Mark

    2014-11-01

    In most parts of Sub-Saharan Africa fertilizers and feeds are costly, not readily available and used sparingly in agricultural production. In many parts of Western Europe, North America, and Oceania fertilizers and feeds are relatively inexpensive, readily available and used abundantly to maximize profitable agricultural production. A case study, dairy systems approach was used to illustrate how differences in feed and manure management in a low-N-input dairy cattle system (Niger, West Africa) and a high-N-input dairy production system (Wisconsin, USA) impact agricultural production and environmental N loss. In Niger, an additional daily feed N intake of 114 g per dairy animal unit (AU, 1000 kg live weight) could increase annual milk production from 560 to 1320 kg AU-1, and the additional manure N could greatly increase millet production. In Wisconsin, reductions in daily feed N intake of 100 g AU-1 would not greatly impact milk production but decrease urinary N excretion by 25% and ammonia and nitrous oxide emissions from manure by 18% to 30%. In Niger, compared to the practice of housing livestock and applying dung only onto fields, corralling cattle or sheep on cropland (to capture urinary N) increased millet yields by 25% to 95%. The additional millet grain due to dung applications or corralling would satisfy the annual food grain requirements of 2-5 persons; the additional forage would provide 120-300 more days of feed for a typical head of cattle; and 850 to 1600 kg ha-1 more biomass would be available for soil conservation. In Wisconsin, compared to application of barn manure only, corralling heifers in fields increased forage production by only 8% to 11%. The application of barn manure or corralling increased forage production by 20% to 70%. This additional forage would provide 350-580 more days of feed for a typical dairy heifer. Study results demonstrate how different approaches to feed and manure management in low-N-input and high-N-input dairy cattle

  6. Abstract bodies, concrete risks: clinical devices and the health of ova donors in Argentine reproductive medicine

    OpenAIRE

    Lucía Ariza

    2016-01-01

    Using a methodological perspective grounded in science and technology studies, this article analyzes two sociotechnical devices used in Argentine reproductive medicine (biostatistical measures and donation registries) with the aim of controlling both the so-called “genetic risk” arising from the use of donated ova as well as the health risks to female donors. By examining how the deployment of monitoring criteria disregards the specificity of ova donation, the article suggests that it is not ...

  7. Draft Genome Sequences of Four Enterococcus faecium Strains Isolated from Argentine Cheese

    Science.gov (United States)

    Martino, Gabriela P.; Quintana, Ingrid M.; Espariz, Martín; Blancato, Victor S.; Gallina Nizo, Gabriel; Esteban, Luis

    2016-01-01

    We report the draft genome sequences of four Enterococcus faecium strains isolated from Argentine regional cheeses. These strains were selected based on their technological properties, i.e., their ability to produce aroma compounds (diacetyl, acetoin, and 2,3-butanediol) from citrate. The goal of our study is to provide further genetic evidence for the rational selection of enterococci strains based on their pheno- and genotype in order to be used in cheese production. PMID:26847907

  8. Survey of Argentine health researchers on the use of evidence in policymaking.

    Directory of Open Access Journals (Sweden)

    Adrijana Corluka

    Full Text Available In this study, Argentine health researchers were surveyed regarding their perceptions of facilitators and barriers to evidence-based policymaking in Argentina, as well as their publication activities, and research environment satisfaction.A self-administered online survey was sent to health researchers in Argentina. The survey questions were based on a preceding qualitative study of Argentine health researchers, as well as the scientific literature.Of the 647 researchers that were reached, 226 accessed the survey, for a response rate of 34.9%. Over 80% of researchers surveyed had never been involved in or contributed to decision-making, while over 90% of researchers indicated they would like to be involved in the decision-making process. Decision-maker self-interest was perceived to be the driving factor in the development of health and healthcare policies. Research conducted by a research leader was seen to be the most influential factor in influencing health policy, followed by policy relevance of the research. With respect to their occupational environment, researchers rated highest and most favourably the opportunities available to present, discuss and publish research results and their ability to further their education and training. Argentine researchers surveyed demonstrated a strong interest and willingness to contribute their work and expertise to inform Argentine health policy development.Despite Argentina's long scientific tradition, there are relatively few institutionalized linkages between health research results and health policymaking. Based on the results of this study, the disconnect between political decision-making and the health research system, coupled with fewer opportunities for formalized or informal researcher/decision-maker interaction, contribute to the challenges in evidence informing health policymaking in Argentina. Improving personal contact and the building of relationships between researchers and policymakers in

  9. The Falklands War: Understanding the Power of Context in Shaping Argentine Strategic Decisions

    Science.gov (United States)

    2007-09-01

    Malvinas—La Defensa de Puerto Argentino, Comandos en Accion and Testimonio de su Gobernador.65 Additional insight into the origins of the conflict can be... planning . For a defending force, in this case the Argentines, the goal 128 Stewart, 60. 129... planned naval movement against the British task force. The attack was to be a two-pronged assault with the Belgrano leading the southern element of

  10. Therapeutic Argentine tango dancing for people living with Parkinson’s disease: a feasibility study

    OpenAIRE

    Blandy, Laura M.; Meg E. Morris; Winifred A Beevers

    2015-01-01

    Background: Individuals living with Parkinson’s disease (PD) can experience a range of movement disorders. Therapeutic dance is enjoyable and thought to improve mobility, balance and well being in some people with PD. The primary objective of this study was to evaluate the feasibility and safety of a 4 week Argentine tango dance program for people with PD. Methods: Six community dwelling individuals with mild-moderate PD were recruited from Parkinson’s support groups, movement disorder clini...

  11. Inhibition of cyclooxygenase activity by standardized hydroalcoholic extracts of four Asteraceae species from the Argentine Puna

    OpenAIRE

    Alberto,M.R.; Zampini,I.C.; Isla, M. I.

    2009-01-01

    We determined the anti-inflammatory activity of standardized extracts of four medicinal plant species (Baccharis incarum, B. boliviensis, Chuquiraga atacamensis, Parastrephia lucida) that grow in the Argentine Puna (3800 m above sea level) and that are used to reduce oxidative stress and alleviate gout and arthritic pain. The extracts of plant aerial parts were standardized in terms of total phenolic compounds and flavone/flavanone content and free radical scavenging activity. All extracts sh...

  12. The executive and legislative branches and trade unions in the Argentine social security reform

    Directory of Open Access Journals (Sweden)

    Sidney Jard da Silva

    2007-01-01

    Full Text Available This article analyzes the interaction between organized labor and government during reform of the pension system in Argentina. The purpose is to investigate the political and institutional conditions favorable to the inclusion of trade unions in a negotiated pension reform process. The Argentine pattern of union-government interaction was shown to be shaped more by the peculiarities of the decision-making process than by the demands and power of union organizations.

  13. Transcriptome analyses identify five transcription factors differentially expressed in the hypothalamus of post- versus prepubertal Brahman heifers.

    Science.gov (United States)

    Fortes, M R S; Nguyen, L T; Weller, M M D C A; Cánovas, A; Islas-Trejo, A; Porto-Neto, L R; Reverter, A; Lehnert, S A; Boe-Hansen, G B; Thomas, M G; Medrano, J F; Moore, S S

    2016-09-01

    Puberty onset is a developmental process influenced by genetic determinants, environment, and nutrition. Mutations and regulatory gene networks constitute the molecular basis for the genetic determinants of puberty onset. The emerging knowledge of these genetic determinants presents opportunities for innovation in the breeding of early pubertal cattle. This paper presents new data on hypothalamic gene expression related to puberty in (Brahman) in age- and weight-matched heifers. Six postpubertal heifers were compared with 6 prepubertal heifers using whole-genome RNA sequencing methodology for quantification of global gene expression in the hypothalamus. Five transcription factors (TF) with potential regulatory roles in the hypothalamus were identified in this experiment: , , , , and . These TF genes were significantly differentially expressed in the hypothalamus of postpubertal versus prepubertal heifers and were also identified as significant according to the applied regulatory impact factor metric ( Brahman). Knowledge of key mutations involved in genetic traits is an advantage for genomic prediction because it can increase its accuracy.

  14. Pathogens in Dairy Farming: Source Characterization and Groundwater Impacts

    Science.gov (United States)

    Atwill, E. R.; Watanabe, N.; Li, X.; Hou, L.; Harter, T.; Bergamaschi, B.

    2007-12-01

    Intense animal husbandry is of growing concern as a potential contamination source of enteric pathogens as well as antibiotics. To assess the public health risk from pathogens and their hydrologic pathways, we hypothesize that the animal farm is not a homogeneous diffuse source, but that pathogen loading to the soil and, therefore, to groundwater varies significantly between the various management units of a farm. A dairy farm, for example, may include an area with calf hutches, corrals for heifers of various ages, freestalls and exercise yards for milking cows, separate freestalls for dry cows, a hospital barn, a yard for collection of solid manure, a liquid manure storage lagoon, and fields receiving various amounts of liquid and solid manure. Pathogen shedding and, hence, therapeutic and preventive pharmaceutical treatments vary between these management units. We are implementing a field reconnaissance program to determine the occurrence of three different pathogens ( E. coli, Salmonella, Campylobacter) and one indicator organism ( Enterococcus) at the ground-surface and in shallow groundwater of seven different management units on each of two farms, and in each of four seasons (spring/dry season, summer/irrigation season, fall/dry season, winter/rainy season). Initial results indicate that significant differences exist in the occurrence of these pathogens between management units and between organisms. These differences are weakly reflected in their occurrence in groundwater, despite the similarity of the shallow geologic environment across these sites. Our results indicate the importance of differentiating sources within a dairy farm and the importance of understanding subsurface transport processes for these pathogens.

  15. A new application of pelvis area data as culling tool to aid in the management of dystocia in heifers.

    Science.gov (United States)

    Holm, D E; Webb, E C; Thompson, P N

    2014-05-01

    Although fetomaternal disproportion is the major cause of dystocia in heifers, pelvis area (PA) is not recommended as a culling tool due to its relatively low importance and genetic correlation with calf birth weight (BWT), the most important factor associated with dystocia. The objective of this observational study of 484 limited bred yearling beef heifers was to compare the effects of different methods of adjustment of PA data for culling to select against dystocia. Multivariable analyses were used to determine predictors of PA, calf BWT, and dystocia. Hypothetical culling rates of 10 and 20% were then applied after ranking heifers by each of the following: unadjusted PA, PA adjusted to 365 d of age by subtracting 0.27 cm(2) per day of age difference between each heifer's age and 365 d (APA), PA:prebreeding BW ratio (PA:BW), PA adjusted to the median BW of the group using the regression coefficient of PA on BW within age group (BWPA), and PA similarly adjusted to the median lean BW (LBWPA). Dam parity, sire, prebreeding age, prebreeding BW, and prebreeding BCS were associated with PA whereas dam parity, sire, own BWT, PA, AI bull, and calf gender were associated with calf BWT (P dystocia (P dystocia. After hypothetical culling by PA, retained heifers were heavier and had a higher calving rate and calves tended to be heavier at birth compared to culled heifers, but dystocia rates were not different. Culling by APA resulted in similar effects, except that dystocia rate tended to be lower in retained heifers. Culling by PA:BW resulted in lower dystocia rate in retained than in culled heifers, but retained heifers had lower prebreeding BW than culls. Culling by BWPA and LBWPA resulted in lower proportions with dystocia and a tendency towards higher calving rates in the retained heifers, without affecting the prebreeding BW or calf BWT. It is concluded that pelvimetry is a useful culling tool to aid in the management of dystocia in yearling heifers and that adjustment

  16. Strengthening primary care as main point of entry to the Argentine health system

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Díaz

    2013-09-01

    Full Text Available Background. The Argentine health system is characterized by fragmentation of care, major spending levels and indicators that beg to improve. It is composed of three subsystems: public, private and social security. Despite the efforts of these subsystems, patients do not perceive primary health care as a valid point of entry to health care, preferring to haphazardly choose from a roster of providers. Purpose. To describe and reframe the challenges facing primary health care in order to become the main point of entry to the Argentine health system. Analysis. The magnitude of health inequities have been amply reported, wherein differences in vulnerability and exposure to disease lead to greater social stratification. This situation makes it necessary to organize a coordinated, effective and sustainable strategy to tackle existing health problems, new challenges and improve equity. Conclusion. Primary health care should become the main point of entry to the Argentine health system. This is a long term endeavor that requires joint and coordinated decisions aimed at strengthening a model of care based on prevention and early detection of disease, together with efficient spending and an improvement in the quality of life of the population.

  17. Hydrocarbon-released nestmate aggression in the Argentine ant, Linepithema humile, following encounters with insect prey.

    Science.gov (United States)

    Liang, D; Blomquist, G J; Silverman, J

    2001-07-01

    Argentine ants, Linepithema humile, were attacked by their nestmates following contact with a particular prey item, the brown-banded cockroach, Supella longipalpa. Contact with prey, as brief as 2 min, provoked nestmate aggression. Argentine ants contaminated with hydrocarbons extracted from S. longipalpa also released nestmate aggression behavior similar to that released by the whole prey item, confirming the involvement of hydrocarbons. In contrast to S. longipalpa, little or no nestmate aggression was induced by other ant prey from diverse taxa. A comparison of prey hydrocarbon profiles revealed that all hydrocarbons of S. longipalpa were very long chain components with 33 or more carbons, while other prey had either less, or none, of the very long chain hydrocarbons of 33 carbons or greater. We identified the hydrocarbons of S. longipalpa and some new groups of long chain hydrocarbons of L. humile. The majority of S. longipalpa hydrocarbons were 35 and 37 carbons in length with one to three methyl branches, and closely resembled two previously unidentified groups of compounds from L. humile of similar chain length. The hydrocarbons of S. longipalpa and L. humile were compared and their role in the Argentine ant nestmate recognition is discussed.

  18. Acclimation effects on critical and lethal thermal limits of workers of the Argentine ant, Linepithema humile.

    Science.gov (United States)

    Jumbam, Keafon R; Jackson, Susan; Terblanche, John S; McGeoch, Melodie A; Chown, Steven L

    2008-06-01

    For the Argentine ant Linepithema humile, bioclimatic models often predict narrower optimal temperature ranges than those suggested by behavioural and physiological studies. Although water balance characteristics of workers of this species have been thoroughly studied, gaps exist in current understanding of its thermal limits. We investigated critical thermal minima and maxima and upper and lower lethal limits following acclimation to four temperatures (15, 20, 25, 30 degrees C; 12L:12D photoperiod) in adult workers of the Argentine ant, L. humile, collected from Stellenbosch, South Africa. At an ecologically relevant rate of temperature change of 0.05 degrees Cmin(-1), CTMax varied between 38 and 40 degrees C, and CTMin varied between 0 and 0.8 degrees C. In both cases the response to acclimation was weak. A significant time by exposure temperature interaction was found for upper and lower lethal limits, with a more pronounced effect of acclimation at longer exposure durations. Upper lethal limits varied between 37 and 44 degrees C, whilst lower lethal limits varied between -4 and -10.5 degrees C, with an acclimation effect more pronounced for upper than lower lethal limits. A thermal envelope for workers of the Argentine ant is provided, demonstrating that upper thermal limits do likely contribute to distributional limits, but that lower lethal limits and limits to activity likely do not, or at least for workers who are not exposed simultaneously to the demands of load carriage and successful foraging behaviour.

  19. Effect of protein supplementation and forage allowance on the growth and reproduction of beef heifers grazing stockpiled tall fescue.

    Science.gov (United States)

    Lyons, S E; Shaeffer, A D; Drewnoski, M E; Poore, M H; Poole, D H

    2016-04-01

    Stockpiled tall fescue can provide adequate winter forage for beef cattle, although unsupplemented replacement heifers may display marginal performance before breeding. The objective of this study was to determine if protein supplementation and/or additional forage improves growth and reproductive performance of replacement heifers grazing stockpiled fescue. Cattle averaging 272 ± 1.59 kg were stratified by BW and then randomly assigned to 1 of 4 plots within a pasture replication. Treatment combinations were assigned in a 2 × 2 factorial arrangement and included 1) a conservative forage allocation ("normal," targeting 85% forage use) and mineral supplement (normal forage allocation with mineral supplement [FM]), 2) normal forage allocation with protein tub (FT), 3) more liberal forage allocation ("extra," targeting 70% forage use) and mineral supplement (extra forage allocation with mineral supplement [EM]), and 4) "extra forage allocation with protein tub (ET). Treatments were administered for 8 wk from early November to early January. Heifers were fed fescue hay for 1 wk before breeding in late January. Heifers were synchronized with the 7-d CO-Synch + controlled internal drug release device protocol and inseminated in late January. Heifers were checked for pregnancy by ultrasonography at 35 and 90 d after AI. Main and interaction effects between the 2 treatments were determined. Total supplement intake was greater for protein tub than mineral supplement (0.36 vs. 0.11 kg·heifer·d, respectively; Reproductive tract scores, pelvic area, and AI pregnancy rates were not different between treatments ( > 0.05). Overall, feeding a protein supplement or providing extra forage increased gain and interacted to increase BCS but did not have an effect on reproductive performance. Supplementing with protein and providing extra forage are strategies that can increase gain in heifers, which could aid heifers in reaching puberty before estrous synchronization.

  20. A fenbendazole oral drench in addition to an ivermectin pour-on reduces parasite burden and improves feedlot and carcass performance of finishing heifers compared with endectocides alone.

    Science.gov (United States)

    Reinhardt, C D; Hutcheson, J P; Nichols, W T

    2006-08-01

    Two studies utilizing 1,862 yearling heifers were conducted to determine the effects of a fenbendazole oral drench in addition to an ivermectin pour-on (SG+IVPO), compared with an ivermectin pour-on (IVPO) or a doramectin injectable (DMX) alone, on parasite burden, feedlot performance, and carcass merit of feedlot cattle. In the first study, heifers receiving the SG+IVPO had fewer (P = 0.02) cattle retreated for disease and 73% fewer (P = 0.06) worm eggs per fecal sample 98 d after treatment than heifers treated with IVPO. Heifers treated with SG+IVPO consumed more DM, had greater ADG, were heavier at slaughter, and had heavier carcasses than IVPO-treated heifers (P fenbendazole oral drench and an ivermectin pour-on reduced parasite burden and increased feed intake, ADG, and carcass weight in feedlot heifers compared with treatment with an endectocide alone.

  1. U.S. Dairy Forage Research Center

    Data.gov (United States)

    Federal Laboratory Consortium — Vision: Leading the world in integrated dairy forage systems research. Mission: Providing dairy industry solutions for food security, environmental sustainability,...

  2. U.S. DAIRY FORAGE RESEARCH CENTER

    Data.gov (United States)

    Federal Laboratory Consortium — Vision: Leading the world in integrated dairy forage systems research. Mission: Providing dairy industry solutions for food security, environmental sustainability,...

  3. Genome-wide association for the outcome of fixed-time artificial insemination of Brahman heifers in northern Australia.

    Science.gov (United States)

    Porto-Neto, L R; Edwards, S; Fortes, M R S; Lehnert, S A; Reverter, A; McGowan, M

    2015-11-01

    Fixed-time AI (FTAI) is a powerful tool for genetic improvement of extensively managed beef cattle. A genomewide association study (GWAS) was conducted to investigate genes and genetic markers associated with the outcome (pregnant or not pregnant) of FTAI in 614 commercial Brahman heifers genotyped for 18,895 SNP and imputed to 51,588 SNP. The likelihood of Brahman heifers becoming pregnant after hormonal treatment to synchronize ovulation followed by FTAI was influenced by the content of their genomes, as determined by a principal component analysis. The principal component analysis involved comparisons between the studied heifers and populations of known and ancestry. The heritability of FTAI outcome was = 0.18, which is higher than for most other reproductive outcome traits. The number of SNP associated with FTAI outcome was 101 ( Brahman heifer puberty and postpartum anestrus interval, 3 genomic regions emerge as important for overall Brahman heifer fertility, which mapped to chromosomes 1, 7, and 9. Further analyses, including improved genome annotation, are required to elucidate the link between these regions and heifer fertility. Additional studies are needed to confirm SNP and gene associations reported herein and further elucidate the genetics of FTAI outcome. Future GWAS should target other Braham populations and additional cattle breeds with FTAI records, including breeds with higher ancestry.

  4. Muddy conditions reduce hygiene and lying time in dairy cattle and increase time spent on concrete.

    Science.gov (United States)

    Chen, Jennifer M; Stull, Carolyn L; Ledgerwood, David N; Tucker, Cassandra B

    2017-03-01

    Dairy cattle spend less time lying and show signs of increased stress when housed in rainy and windy conditions, but no work has separated the effects of exposure to inclement weather from muddy conditions underfoot. Our objective was to evaluate the effects of muddy conditions alone on lying behavior, hygiene, and physiological responses. We housed pairs of pregnant, nonlactating dairy cattle (n = 12; 6 primigravid heifers, 6 multiparous cows) in enclosed pens with dirt floors and a concrete feed apron. Cattle were exposed to 3 levels of soil moisture: 90 (dry), 74 (muddy), or 67% (very muddy) dry matter for 5 d each in a replicated 3 × 3 Latin square design. Lying time was measured on all days with data loggers, and lying locations and postures were recorded on the final day of each treatment. Before and after each treatment, blood samples were collected, and the percentage of dirty surface area was measured on the udder, hind leg, and side of each animal. Cattle spent less time lying down in muddier conditions, especially in the first 24 h of exposure, when cows and heifers spent only 3.2 and 5.8 h, respectively, lying down in the muddiest treatment compared with 12.5 and 12.7 h on dry soil. When the soil was dry, cattle never chose to lie down on concrete, but in muddier conditions they spent a greater proportion of their lying time on concrete (mean ± SE: 56 ± 14 and 10 ± 8% in the very muddy and muddy treatments, respectively). The shift in lying location was more marked for heifers, and all 6 spent ≥87% of their lying time on concrete in the muddiest treatment. When cattle chose to lie down on wetter soil, they limited the surface area exposed to their surroundings by tucking their legs beneath their bodies (mean ± SE: 30 ± 11, 15 ± 4, and 5 ± 2% of lying observations in the very muddy, muddy, and dry treatments, respectively). Despite cattle spending less time on wetter soil, all 3 measured body parts became dirtier in muddier conditions (1.4-, 1

  5. Antral follicles population in heifers and cows of Nelore and Girolando breeds

    Directory of Open Access Journals (Sweden)

    Jair Sábio de Oliveira Junior

    2015-12-01

    Full Text Available The aim of this study was to evaluate ovarian antral follicle populations (OAFP of Nelore and Girolando breed heifers (12–18 months old and cows (24–60 months old. Animals were assigned to four groups: (1 Nelore cows (n = 18, (2 Girolando cows (n = 20, (3 Nelore heifers (n = 7, and (4 Girolando heifers (n = 7. Cows were treated to synchronize follicular wave emergence by implantation of an intravaginal device containing 1.9 g of progesterone, as well as intramuscular administration of 2 mg of estradiol benzoate and 25 mg of dinoprost. This synchronization treatment was administered at a random day of the estrous cycle of each cow, designated D0. Intravaginal devices were removed on D7, and on D11, OAFP counts were performed by transvaginal ovarian ultrasound. For each cow, all follicles ?3 mm in diameter were counted in both ovaries and counts were performed three times at 35-day intervals. Counts were also obtained from heifers, but these animals were not treated for synchronization of follicular wave emergence. Analysis of variance (ANOVA with Tukey’s test and Pearson’s correlation test were used to compare mean OAFPs between counts as well as mean OAFPs between breed and age groups. No differences were observed in mean OAFPs between Nelore and Girolando cows (30.9 vs. 26.7, respectively; P > 0.05 or heifers (16.2 vs. 18.1, respectively; P > 0.05. However, within each breed, there were differences in mean OAFPs between heifers and cows (for Nelore cattle: 16.2 and 30.9, respectively; for Girolando cattle: 18.1 and 26.7, respectively; both P < 0.05. In conclusion, OAFPs were similar between Nelore and Girolando breeds and were influenced by age. Furthermore, we observed a high correlation for individual animals between the mean numbers of follicles counted in both ovaries and total number of follicles counted in either the right or left ovary, indicating that the evaluation of a single ovary is sufficient to estimate the OAFP of an

  6. Variability in residual feed intake and nutrient utilization in Murrah buffalo heifers.

    Science.gov (United States)

    Negesse, Tegene; Datt, Chander; Kundu, S S

    2016-12-01

    A feeding trial with 18 Murrah buffalo heifers (238 ± 63 kg; 1.7 ± 0.4 years old) was conducted for 57 days, and feed intake and body weight were recorded followed by 7 days of urine and feces collection. Heifers were grouped into low (RFI-I) and high (RFI-II) feed efficiency groups by regressing DMI (g head(-1) day(-1)) on BWG (g head(-1) day(-1)) and mid-test MBW (kg). RFI-II heifers had slightly higher DMI (g head(-1) day(-1) and expressed per unit of BW, %BW, MBW, mid-test BW, and mid-test MBW) and all associated nutrient intakes, BWG, feed efficiency traits (FCR, CPCR), digestibility of nutrients, and retentions of crude protein and fat over RFI-I heifers. The corresponding intake values (kg head(-1) day(-1)) for RFI-I versus RFI-II were the following: DMI (6.73 ± 0.56 vs 6.51 ± 0.50), CPI (0.99 ± 0.008 vs 0.97 ± 0.07), DOMI (5.06 ± 0.47 vs 5.11 ± 0.42), and TDNI (4.95 ± 0.47 vs 5.00 ± 0.42). BWG (669 ± 52 vs 776 ± 47 g head(-1) day(-1)), feed efficiency traits (FCR: 10.32 ± 1.16 vs 8.77 ± 1.04 and CPCR: 1.52 ± 0.17 vs 1.30 ± 0.16), N balance (38 ± 9 vs 45 ± 8 g N head(-1) day(-1)), and protein and fat retentions (239 ± 57 vs 282 ± 51 g CP head(-1) day(-1) and 430 ± 6 vs 494 ± 59 g fat head(-1) day(-1)) of RFI-I were less than RFI-II heifers, respectively. Based on the predicted RFI values, RFI-II buffalo heifers could be selected for feed efficiency.

  7. Function of the corpus luteum in beef heifers is affected by acute submaintenance feeding but is not correlated with residual feed intake.

    Science.gov (United States)

    Lents, C A; Randel, R D; Stelzleni, A M; Caldwell, L C; Welsh, T H

    2011-12-01

    Seventy-four Angus and Angus × Hereford heifers were used in 2 successive years (yr 1, n = 43; yr 2, n = 31) to determine if luteal function of heifers during acute submaintenance feeding is related to variation in utilization of feed as determined by residual feed intake (RFI). Residual feed intake was determined for heifers beginning at 12.3 ± 0.1 mo of age in yr 1 and at 9.1 ± 0.1 mo of age in yr 2. Heifers were assigned to dry-lot pens (n = 6 to 9 heifers/pen) with electronic gates to measure individual feed intake of a total mixed ration for 70 and 72 d in yr 1 and 2, respectively. Residual feed intake was calculated as the difference between actual DMI and expected DMI from linear regression of DMI on mid-test BW(0.75) and ADG. At 14.4 ± 0.1 mo of age, all heifers were provided a restricted amount of feed to supply 40% of their maintenance energy requirements for 21 d. Estrous cycles of heifers were synchronized with PGF(2α) on d -10, 0, and 11 relative to start of restriction. Concentrations of progesterone in plasma on d 14 to 21 of restriction were used to determine if heifers ovulated. Overall ADG and ADFI were 0.83 ± 0.02 and 7.37 ± 0.67 kg/d, respectively, for yr 1; and 0.50 ± 0.02 and 5.66 ± 0.09 kg/d, respectively, for yr 2. There was no correlation between RFI and BW, ADG, ADFI, or ultrasound measure of backfat, nor was RFI related to concentrations of IGF-I in plasma. All heifers lost BW and had reduced backfat (P feeding. All heifers had reproductive cycles before dietary restriction started. During acute nutritional restriction, 4 heifers became anovulatory. Sixteen heifers had concentrations of progesterone in plasma during restricted feeding that were atypical of normal luteal function. There was no relationship between luteal function during nutrient restriction and RFI of heifers. Circulating IGF-1 was greater at weaning and after restricted feeding in heifers with a smaller RFI (>0.5 SD below the mean) than heifers with a greater RFI

  8. Caring Dairy: A Sustainable Dairy Farming Initiative in Europe

    NARCIS (Netherlands)

    Calker, van K.J.; Hooch Antink, R.H.J.; Beldman, A.C.G.; Mauser, A.

    2005-01-01

    Interest in the concept of sustainability in dairy farming has grown as a result of the continuous pressure on farm incomes, occurrence of animal diseases with a major impact on the image of dairy farming, concerns about animal welfare, and environmental problems caused by agriculture. There are,

  9. Caring Dairy: A Sustainable Dairy Farming Initiative in Europe

    NARCIS (Netherlands)

    Calker, van K.J.; Hooch Antink, R.H.J.; Beldman, A.C.G.; Mauser, A.

    2005-01-01

    Interest in the concept of sustainability in dairy farming has grown as a result of the continuous pressure on farm incomes, occurrence of animal diseases with a major impact on the image of dairy farming, concerns about animal welfare, and environmental problems caused by agriculture. There are, ho

  10. National Beef Quality Audit-2011: In-plant survey of targeted carcass characteristics related to quality, quantity, value, and marketing of fed steers and heifers.

    Science.gov (United States)

    Moore, M C; Gray, G D; Hale, D S; Kerth, C R; Griffin, D B; Savell, J W; Raines, C R; Belk, K E; Woerner, D R; Tatum, J D; Igo, J L; VanOverbeke, D L; Mafi, G G; Lawrence, T E; Delmore, R J; Christensen, L M; Shackelford, S D; King, D A; Wheeler, T L; Meadows, L R; O'Connor, M E

    2012-12-01

    The 2011 National Beef Quality Audit (NBQA-2011) assessed the current status of quality and consistency of fed steers and heifers. Beef carcasses (n = 9,802), representing approximately 10% of each production lot in 28 beef processing facilities, were selected randomly for the survey. Carcass evaluation for the cooler assessment of this study revealed the following traits and frequencies: sex classes of steer (63.5%), heifer (36.4%), cow (0.1%), and bullock (0.03%); dark cutters (3.2%); blood splash (0.3%); yellow fat (0.1%); calloused rib eye (0.05%); overall maturities of A (92.8%), B (6.0%), and C or greater (1.2%); estimated breed types of native (88.3%), dairy type (9.9%), and Bos indicus (1.8%); and country of origin of United States (97.7%), Mexico (1.8%), and Canada (0.5%). Certified or marketing program frequencies were age and source verified (10.7%), ≤A(40) (10.0%), Certified Angus Beef (9.3%), Top Choice (4.1%), natural (0.6%), and Non-Hormone-Treated Cattle (0.5%); no organic programs were observed. Mean USDA yield grade (YG) traits were USDA YG (2.9), HCW (374.0 kg), adjusted fat thickness (1.3 cm), LM area (88.8 cm2), and KPH (2.3%). Frequencies of USDA YG distributions were YG 1, 12.4%; YG 2, 41.0%; YG 3, 36.3%; YG 4, 8.6%; and YG 5, 1.6%. Mean USDA quality grade (QG) traits were USDA quality grade (Select(93)), marbling score (Small(40)), overall maturity (A(59)), lean maturity (A(54)), and skeletal maturity (A(62)). Frequencies of USDA QG distributions were Prime, 2.1%; Choice, 58.9%; Select, 32.6%; and Standard or less, 6.3%. Marbling score distribution was Slightly Abundant or greater, 2.3%; Moderate, 5.0%; Modest, 17.3%; Small, 39.7%; Slight, 34.6%; and Traces or less, 1.1%. Carcasses with QG of Select or greater and YG 3 or less represented 85.1% of the sample. This is the fifth benchmark study measuring targeted carcass characteristics, and information from this survey will continue to help drive progress in the beef industry. Results will

  11. Foraging activity and dietary spectrum of the Argentine ant (Hymenoptera: Formicidae) in invaded natural areas of the northeast Iberian Peninsula.

    Science.gov (United States)

    Abril, S; Oliveras, J; Gómez, C

    2007-10-01

    We analyzed the foraging activity and the dietary spectrum of the Argentine ant (Linepithema humile Mayr) and select native ants on cork oaks from Mediterranean open cork oak (Quercus suber) secondary forests. The study areas included invaded and noninvaded zones in close proximity. The Argentine ant's daily foraging activity was correlated to the abiotic factors studied, whereas the seasonal foraging activity was related not only to the variations in the average air temperature, but also to the trophic needs of the colony. Argentine ant workers focused their attention on protein foods during the queens' oviposition periods and during the larvae development phase, and on carbohydrate foods, such as honeydew, when males and workers were hatching. There were no significant differences over the entire year in the quantity of liquid food collected by the Argentine ant workers in comparison with the native ants studied. The solid diet of the Argentine ant on cork oaks is composed of insects, most of which are aphids. Our results have clear applications for control methods based on toxic baits in the invaded natural ecosystems of the Iberian Peninsula.

  12. The distribution and evolutionary history of Wolbachia infection in native and introduced populations of the invasive argentine ant (Linepithema humile).

    Science.gov (United States)

    Tsutsui, Neil D; Kauppinen, Seth N; Oyafuso, Alain F; Grosberg, Richard K

    2003-11-01

    Wolbachia pipientis is a maternally transmitted bacterium that often alters the life history of its insect host to maximize transmission to subsequent generations. Here we report on the frequency and distribution of Wolbachia infection in a widespread invasive species, the Argentine ant (Linepithema humile). We screened 1175 individual Argentine ants from 89 nests on five continents and several islands, including numerous locations in both the native (South American) and introduced ranges. We detected Wolbachia in four of 11 native populations, but only one of 21 introduced populations was infected. In the Argentine ant's native range, the distribution of Wolbachia supergroups A and B was nonoverlapping. By coupling infection frequency data with behaviourally defined colony boundaries, we show that infected and uninfected colonies are often adjacent to one another, supporting the proposition that little female-mediated gene flow occurs among Argentine ant colonies. We also conduct a phylogenetic analysis, and show that the Wolbachia infecting both native and introduced populations of Argentine ants belong to two lineages that appear to be specialized on infecting New World ants. One other lineage of Wolbachia has undergone frequent, recent episodes of horizontal transmission between distantly related, introduced insect hosts.

  13. Vaccination of adult animals with a reduced dose of Brucella abortus S19 vaccine to control brucellosis on dairy farms in endemic areas of India.

    Science.gov (United States)

    Chand, Puran; Chhabra, Rajesh; Nagra, Juhi

    2015-01-01

    Bovine brucellosis is an economically important disease which seriously affects dairy farming by causing colossal losses. It can be controlled by practicing vaccination of animals with Brucella abortus S19 vaccine (S19 vaccine). In the present study, adult bovines were vaccinated on seven dairy farms with a reduced dose of S19 vaccine to control brucellosis. Serological screening of adult animals (N = 1,082) by Rose Bengal test (RBT) and ELISA prior to vaccination revealed the presence and absence of brucellosis on five and two farms, respectively. The positive animals (N = 171) were segregated and those which tested negative (N = 911) were vaccinated by conjunctival route with a booster after 4 months. The conjunctival vaccination induced weak antibody response in animals, which vanished within a period of 9 to 12 weeks. Abortion in 12 animals at various stages of pregnancy and post-vaccination was recorded, but none was attributed to S19 vaccine. However, virulent B. abortus was incriminated in six heifers, and the cause of abortion could not be established in six animals. The six aborted heifers perhaps acquired infection through in utero transmission or from the environment which remained undetected until abortion. These findings suggested that vaccination of adult animals with a reduced dose of S19 vaccine by conjunctival route did not produce adverse effects like abortion in pregnant animals and persistent vaccinal antibody titers, which are the major disadvantages of subcutaneous vaccination of adult animals.

  14. A spreadsheet-based model demonstrating the nonuniform economic effects of varying reproductive performance in Ohio dairy herds.

    Science.gov (United States)

    Meadows, C; Rajala-Schultz, P J; Frazer, G S

    2005-03-01

    A spreadsheet-based model was developed to estimate the economic effect of varying reproductive performance in dairy herds. Scenarios were created to model an average cow with respect to production, herd lifetime, and reproductive events. Average milk yield per day of life as well as lifetime calf and replacement heifer production were examined. Additional inputs representing milk, feed, semen, calf, and salvage prices were used to calculate net cash flow for each day of herd life for the average cow in a scenario. Economic comparison of different scenarios was accomplished using an equivalent annual cash flow (annuity) methodology.Herd performance measures and prices representative of Ohio dairy herds were used to establish a baseline average cow that had a 160-d calving-to-conception interval [days open (DO)]. Alternative scenarios that differed from baseline in DO, annual culling rate, and feed and milk prices were created to characterize the effects of changes. Under scenario inputs representative of typical Ohio dairy herds, the model indicated that a lower annual culling rate (25%) was preferable to higher annual culling rates (34 or 45%). The model estimated maximum average milk yield per day of life to occur at 110 DO. At 34% annual culling rate, calves and replacement heifers produced per lifetime declined as DO increased; beyond 150 DO, the modeled cow produced less than 1 replacement heifer per lifetime. The model also estimated a loss of $1.37 per cow per year for a 1-d increase in DO beyond 160 d. At 20% higher feed and milk prices, the model estimated a loss of $1.52 per cow per year; at 20% lower feed and milk prices, the model estimated a loss of $1.23 per cow per year. Furthermore, the model suggested that the loss associated with a 1-d increase in DO changed as DO changed. Using baseline inputs, the model calculated losses for a 1-d increase of $0.44 per cow per year at 130 DO and $1.71 per cow per year at 190 DO. The nonuniform nature of the cost

  15. Effect of intensive or extensive systems on buffalo heifers performances: blood metabolite values

    Directory of Open Access Journals (Sweden)

    A. Borghese

    2010-02-01

    Full Text Available Blood nutritional indicators were measured on twenty-six prepubertal 8- mo-old buffalo heifers, weighing a mean of 134 kg to determine the effect of different feeding and management systems. Animals were randomly assigned to an intensive feeding (n=13; IF group or to a pasture system plus hay (n=13; PS group, according to weight and age. Measurements of live weight and blood collection began on day 0 (=date of onset of trial.The heifers were weighed monthly, up to puberty, to evaluate the growth rate and blood samples were withdrawn every three months to assay the concentrations of blood metabolites. Significantly higher (P0.05.

  16. A comprehensive dairy valorization model.

    Science.gov (United States)

    Banaszewska, A; Cruijssen, F; van der Vorst, J G A J; Claassen, G D H; Kampman, J L

    2013-02-01

    Dairy processors face numerous challenges resulting from both unsteady dairy markets and some specific characteristics of dairy supply chains. To maintain a competitive position on the market, companies must look beyond standard solutions currently used in practice. This paper presents a comprehensive dairy valorization model that serves as a decision support tool for mid-term allocation of raw milk to end products and production planning. The developed model was used to identify the optimal product portfolio composition. The model allocates raw milk to the most profitable dairy products while accounting for important constraints (i.e., recipes, composition variations, dairy production interdependencies, seasonality, demand, supply, capacities, and transportation flows). The inclusion of all relevant constraints and the ease of understanding dairy production dynamics make the model comprehensive. The developed model was tested at the international dairy processor FrieslandCampina (Amersfoort, the Netherlands). The structure of the model and its output were discussed in multiple sessions with and approved by relevant FrieslandCampina employees. The elements included in the model were considered necessary to optimally valorize raw milk. To illustrate the comprehensiveness and functionality of the model, we analyzed the effect of seasonality on milk valorization. A large difference in profit and a shift in the allocation of milk showed that seasonality has a considerable impact on the valorization of raw milk.

  17. Dairy cattle production in Europe

    NARCIS (Netherlands)

    Arendonk, van J.A.M.; Liinamo, A.E.

    2003-01-01

    The European Union (EU) is a major player on world markets for most dairy products and produces the largest single share of the global market. Dairying is one of the most profitable sectors of EU agriculture. Milk yields per cow have increased steadily in every member state between 1985 and 1997. Ov

  18. Pain evaluation in dairy cattle

    DEFF Research Database (Denmark)

    Gleerup, Karina Charlotte Bech; Andersen, Pia Haubro; Munksgaard, Lene

    2015-01-01

    Pain compromises the welfare of animals. A prerequisite for being able to alleviate pain is that we are able to recognize it. Potential behavioural signs of pain were investigated for dairy cattle with the aim of constructing a pain scale for use under production conditions. Forty-three cows were...... for the assessment of pain in dairy cattle under production conditions....

  19. Entrepreneurship of Dutch dairy farmers

    NARCIS (Netherlands)

    Bergevoet, R.H.M.

    2005-01-01

    Several developments in the Netherlands as well as in the other countries within the EU are forcing dairy farmers to reconsider their involvement in dairy production. Farmers are being called to account more for the entrepreneurial element of their farming behaviour. Up till now it was unclear how d

  20. Dairy cluster design for Myanmar

    NARCIS (Netherlands)

    Zijlstra, J.; Lee, van der J.

    2015-01-01

    At the request of the Dutch and Myanmar governments, a project team consisting of researchers from Wageningen University & Research centre and experts from dairy processor Royal FrieslandCampina, feed company Royal De Heus and AgriWorks consultancy have developed a design for a dairy cluster in Myan

  1. Ingestive behavior of Nellore heifers grazing receiving the supplement based on propolis or monensin

    Directory of Open Access Journals (Sweden)

    Luiz Juliano Valério Geron

    2014-09-01

    Full Text Available We evaluated the effect of additives the basis of propolis and monensin on ingestive behavior (grazing – GRA, rumination lying – RLY, rumination in foot – RFO, rumination – RUM; idleness lying – ILY, idleness in standing – IDS, idleness – IDL, walking – WAL, posture standing – POS, posture lying – PLY, intake of supplement and water – ISW of heifers in Tifton 85 grazing. The treatments were: no additive (NAD; propolis – PRO (33.24 mg animal-1 of total flavonoid in apigenin, and monensin – MON (100 mg animal-1. Were used five heifers treatment-1 for evaluation of ingestive behavior during 12 hours of total valuation, which was divided into three periods. Used a factorial design into 3 x 3 for evaluation of ingestive behavior as a function of the evaluation periods. Were utilized three paddocks of 2.9 acres of grass Tifton 85. The additives and mineral supplement (50 g animal-1 were provided with 200 g of corn meal to 17 hours. For all activities of the ingestive behaviors observed the effect of period on the time spent on of different activities. The activities of GRA and ISW were higher in the third period (15hours to 19hours compared to the first period (7hours at 11hours. For IDL and PLY, there was a higher time in minutes for heifers treatment with PRO in the period of 7hours at 11hours, compared to other treatments (NAD and MON. Thus, it is concluded that the use of the additive based on propolis enables sodium monensin replacement, to heifers maintained on pasture without changing eating behavior as well as providing greater idleness during the day the without affecting animal performance.

  2. Ultrasonographic evaluation of reproductive tract measures and fat thickness traits in pre-pubertal Nellore heifers

    Directory of Open Access Journals (Sweden)

    Fabio Morato Monteiro

    2012-02-01

    Full Text Available The aim of this study was to evaluate the relationship between reproductive tract and fat thickness measures obtained by ultrasound in prepubertal Nellore heifers. A total of 128 Nellore heifers born in 2006 and 2007 were submitted to ultrasound evaluations (13, 16, 19 and 22 months of age of reproductive tract measures and fat thickness traits. These animals were from a selection experiment (NeC: control line, and NeS: selection line for yearling weight started in 1981. Mean values of ovary area, height of the right uterine horn (HU, maximum follicular diameter (FOL, backfat thickness (BF, rump fat thickness (RF, and body condition score were analyzed. Repeated records were modeled using the PROC MIXED procedure (SAS, fitting a model that included the selection line, year of birth, measurement as fixed effects, and interactions. Body weight differed between the selected (281.48 kg and control (210.51 kg lines. Only the least square means of FOL were lower in the NeC line compared to the NeS line (P < 0.05, although the difference in mean HU between the two lines was of only borderline significance (P = 0.06. The rate of growth for the three reproductive traits was similar in the two lines. Simple and residual correlations between the reproductive and subcutaneous fat traits ranged from low to medium. The highest correlations were observed between HU and RF (Pearson correlation = 0.71 and residual correlation = 0.34. The current results are consistent with the literature, indicating that fat thickness traits are not good predictors of prepubertal reproductive traits in heifers. Further studies are necessary to clarify the relationship between reproduction and body fat in Nellore heifers.

  3. Estrus induction and fertility response in delayed pubertal Kankrej heifers treated with norgestomet ear implant

    Directory of Open Access Journals (Sweden)

    C. F. Chaudhari

    Full Text Available Aim: The study was undertaken to find out the estrus induction and fertility response in delayed pubertal Kankrej heifers treated with norgestomet ear implant. Materials and methods: Total eighteen anoestrus Kankrej heifers of delayed puberty weighed above 250 kg and attained between 30 to 36 months of age were selected and divided in to three groups of six animals each at random to conduct the experiment. Animals in group 1 were implanted Crestar ear implant for 9 days. In addition to this, group 2 received 500 IU of PMSG on the day of implant removal. In group 3, treatment protocol remained same as in group 2, but Inj. Receptal @ 2 ml was given additionally at the time of breeding. Results: All the animals exhibited estrus with average duration of 25.41+ 0.94, 21.95+ 0.20 and 22.68 + 1.46 hours between implant withdrawal and estrus induction in group 1, 2 and 3, respectively. The duration of estrus was significantly (P<0.05 longer (25.61+ 2.95 hours in group 2, followed by group 1 (18.88 + 1.45 hours and group 3 (13.48 + 1.92 hours. The pregnancy rate at induced estrus was 33.33 percent in group 2. In group 1 and group 3 none of the heifers found pregnant at induced estrus. The overall conception rate was maximum in group 2 (66.67 percent followed by group 3 (50 percent and group 1 (33.33 percent after the 3rd service. Conclusion: Although the conception rate at induced estrus was lower, norgestomet ear implant could be utilized to induced estrus in delayed pubertal cow heifers. [Vet. World 2012; 5(8.000: 453-458

  4. Successful management of mummified fetus in a heifer by prostaglandin therapy and episiotomy

    Directory of Open Access Journals (Sweden)

    Gopal Krishan

    2015-03-01

    Full Text Available Fetal mummification is one of the gestation- al accidents that occur due to intra-uterine death of fetus commonly at fourth, fifth and six months of gestation. This report describes the successful management of the mummified fetus in a five year old graded Holstein Friesian heifer cow using single dose of prostaglandin F2α analogue and by performing episiotomy. Antibiotic therapy was given to avoid any uterine infection.

  5. Genome-wide association for heifer reproduction and calf performance traits in beef cattle.

    Science.gov (United States)

    Akanno, Everestus C; Plastow, Graham; Fitzsimmons, Carolyn; Miller, Stephen P; Baron, Vern; Ominski, Kimberly; Basarab, John A

    2015-12-01

    The aim of this study was to identify SNP markers that associate with variation in beef heifer reproduction and performance of their calves. A genome-wide association study was performed by means of the generalized quasi-likelihood score (GQLS) method using heifer genotypes from the BovineSNP50 BeadChip and estimated breeding values for pre-breeding body weight (PBW), pregnancy rate (PR), calving difficulty (CD), age at first calving (AFC), calf birth weight (BWT), calf weaning weight (WWT), and calf pre-weaning average daily gain (ADG). Data consisted of 785 replacement heifers from three Canadian research herds, namely Brandon Research Centre, Brandon, Manitoba, University of Alberta Roy Berg Kinsella Ranch, Kinsella, Alberta, and Lacombe Research Centre, Lacombe, Alberta. After applying a false discovery rate correction at a 5% significance level, a total of 4, 3, 3, 9, 6, 2, and 1 SNPs were significantly associated with PBW, PR, CD, AFC, BWT, WWT, and ADG, respectively. These SNPs were located on chromosomes 1, 5-7, 9, 13-16, 19-21, 24, 25, and 27-29. Chromosomes 1, 5, and 24 had SNPs with pleiotropic effects. New significant SNPs that impact functional traits were detected, many of which have not been previously reported. The results of this study support quantitative genetic studies related to the inheritance of these traits, and provides new knowledge regarding beef cattle quantitative trait loci effects. The identification of these SNPs provides a starting point to identify genes affecting heifer reproduction traits and performance of their calves (BWT, WWT, and ADG). They also contribute to a better understanding of the biology underlying these traits and will be potentially useful in marker- and genome-assisted selection and management.

  6. The effect of rearing system on behavioural and immune responses of buffalo heifers

    Directory of Open Access Journals (Sweden)

    A. Bordi

    2010-02-01

    Full Text Available From November 2005 to October 2006 thirty-two buffalo heifers from the same commercial farm were used to evaluate the effect of rearing system on a range of behavioural and immune variables. Sixteen heifers were group-housed in indoor slatted floor pen (3.0 m2/animal with an outdoor paddock (3.0 m2/animal at ~5m above sea level (group IR. Sixteen others were kept at ~600m above sea level. They grazed a fenced Mediterranean maquis of ~40ha (group ER. At the end of the experimental period the animals were subjected to a novel object test. Each animal was exposed to a novel environment (a 6x6-m paddock, where in the middle a traffic cone was present. Avoidance distance at manger was evaluated by an assessor who walked slowly (1 step per second toward each animal with one hand slightly forward until signs of withdrawal. Phytohaemagglutinin (PHA, 1mg/animal was used to perform a skin test based on specific delayed type hypersensitivity. During the novel object test, IR animals touched more and devoted more time to the traffic cone than ER animals (P =0.003 and P=0.008, respectively. Avoidance distance at manger was lower in ER animals than IR (P=0.004. Skin thickness after PHA injection was higher in ER heifers than in IR (P=0.003. The results indicated that an extensive rearing system based on pasture seems to be a valid method to promote welfare and sustainability of buffalo heifer.

  7. Dairy Proteins and Energy Balance

    DEFF Research Database (Denmark)

    Bendtsen, Line Quist

    High protein diets affect energy balance beneficially through decreased hunger, enhanced satiety and increased energy expenditure. Dairy products are a major source of protein. Dairy proteins are comprised of two classes, casein (80%) and whey proteins (20%), which are both of high quality......, but casein is absorbed slowly and whey is absorbed rapidly. The present PhD study investigated the effects of total dairy proteins, whey, and casein, on energy balance and the mechanisms behind any differences in the effects of the specific proteins. The results do not support the hypothesis that dairy...... proteins, whey or casein are more beneficial than other protein sources in the regulation of energy balance, and suggest that dairy proteins, whey or casein seem to play only a minor role, if any, in the prevention and treatment of obesity....

  8. Dairy beverages and energy balance

    DEFF Research Database (Denmark)

    Astrup, Arne; Chaput, Jean-Philippe; Gilbert, Jo-Anne

    2010-01-01

    High dairy intakes have been associated with lower rates of obesity in observational studies, but mechanisms to explain the association are lacking. A high intake of dairy protein reduces spontaneous food intake and may be one important mechanism, but more specific effects of dairy calcium seem...... to exist. We have found that high versus low calcium intakes from dairy products had no effect on 24-h energy expenditure or substrate oxidation rates, but fecal fat excretion increased approximately 2.5-fold on the high-calcium diets. In a meta-analysis of intervention studies we found that increasing...... dairy calcium intake by 1200mg/day resulted in increased fecal fat excretion by 5.2 (1.6-8.8) g/day. Newer research shows that humans possess taste receptors for calcium in the gastrointestinal tract and that signaling may be linked to appetite regulation. A new line of evidence suggests...

  9. Dairy Proteins and Energy Balance

    DEFF Research Database (Denmark)

    Bendtsen, Line Quist

    High protein diets affect energy balance beneficially through decreased hunger, enhanced satiety and increased energy expenditure. Dairy products are a major source of protein. Dairy proteins are comprised of two classes, casein (80%) and whey proteins (20%), which are both of high quality......, but casein is absorbed slowly and whey is absorbed rapidly. The present PhD study investigated the effects of total dairy proteins, whey, and casein, on energy balance and the mechanisms behind any differences in the effects of the specific proteins. The results do not support the hypothesis that dairy...... proteins, whey or casein are more beneficial than other protein sources in the regulation of energy balance, and suggest that dairy proteins, whey or casein seem to play only a minor role, if any, in the prevention and treatment of obesity....

  10. Crude glycerin in diets for Nelore heifers on pasture in dry season

    Directory of Open Access Journals (Sweden)

    Gonçalo Mesquita da Silva

    2015-02-01

    Full Text Available This study aimed to evaluate the inclusion of crude glycerin (CG in the diet of Nellore heifers grazing Brachiaria brizantha during the dry season, on nutrients intake and digestibility, performance, reproductive efficiency and economic viability. Sixty Nelore heifers with initial average weight of 285.89 ± 18.74 kg and approximately 19 ± 2 months of age, were distributed in a completely randomized design with five diets containing 0.0; 4.0; 8.0; 12.0 and 16.0% of CG inclusion in the diet. The average dry matter (DM daily intake showed decreasing linear effect (P 0.05, with a mean value of 50.93%. The average daily gain (ADG of heifers showed decreasing linear effect (P0.05 by dietary inclusion of GB, with average values of 75% and 1.29 doses pregnant-¹, respectively. The economic viability indicators were not positive in the short and medium term. Supplements for over 0.7% of the PC in animals maintained in Brachiaria brizantha with low nutritional quality, it is not recommended to include GB, since its inclusion in any level reduced around 15% weight gain. However, depending on the cost of coproduct, it can be includes up to 16% in the diet, even considering this drop in performance.

  11. Impact of hard vs. soft wheat and monensin level on rumen acidosis in feedlot heifers.

    Science.gov (United States)

    Yang, W Z; Xu, L; Zhao, Y L; Chen, L Y; McAllister, T A

    2014-11-01

    Many feedlot finishing diets include wheat when the relative wheat prices are low. This study was conducted to examine the responses in ruminal pH and fermentation as well as site and extent of digestion from substituting soft or hard wheat for barley grain and to determine whether an elevated monensin concentration might decrease indicators of ruminal acidosis in feedlot heifers. Five ruminally cannulated beef heifers were used in a 5 × 5 Latin square with 2 × 2 + 1 factorial arrangement. Treatments included barley (10% barley silage, 86% barley, 4% supplement, with 28 mg monensin/kg DM) and diets where barley was substituted by either soft or hard wheat with either 28 or 44 mg monensin/kg diet DM. Intake of DM was not affected by grain source, whereas increasing monensin with wheat diets reduced (P type or monensin level. Total VFA concentrations were greater (P type. The molar proportion of propionate was greater (P Feeding soft vs. hard wheat delivered a greater (P feed use by heifers fed wheat-based finishing diets.

  12. Seasonal foraging patterns of forest-grazing Japanese Black heifers with increased plasma total antioxidant capacity.

    Science.gov (United States)

    Haga, Satoshi; Nakano, Miwa; Nakao, Seiji; Hirano, Kiyoshi; Yamamoto, Yoshito; Sasaki, Hiroyuki; Ishizaki, Hiroshi

    2016-02-01

    Forest-grazing enables the intake of high total antioxidant capacity (TAC) plants that might be beneficial for the TAC status of cattle. This study evaluated the relation between the seasonal foraging patterns of forest-grazing Japanese Black (JB) heifers or the TAC levels in shrubs and trees and the changes of plasma TAC. We examined 12 JB heifers, four each of which were allocated to forest-grazing (F), pasture-grazing, and pen-housed groups. The plasma TAC level in F heifers on July 26, August 13, 30 and September 17 were significantly higher than those on April 27 and June 4 (P < 0.05). In F group, the mean rates of foraging frequency (FF) of shrubs and trees during July 5-8 and September 13-16 were much higher than that during May 31-June 3 (P < 0.05). The rate of FF of grass significantly decreased later in the season (P < 0.05). The mean TAC levels in these shrubs and trees were higher than those in grasses, concentrates, and timothy hay. Results suggest that an important factor in the increase of plasma TAC in forest-grazing cattle might be the increased foraging of TAC-rich shrubs and trees during summer-fall.

  13. Carcass characteristics, meat quality, feeding behavior of Nelore heifers fed diets containing sunflower pie

    Directory of Open Access Journals (Sweden)

    Karine Regina Alves

    2016-05-01

    Full Text Available The aim was to evaluate the feeding behavior, carcass characteristics and meat quality of Nelore heifers fed sunflower pie replacing cottonseed meal. They were used 30 heifers with average initial weight of 274 kg ± 28 kg and average age of 24 months, confined for 76 days. The design was completely randomized with five treatments (0, 150, 300, 450 and 600 g kg-1 DM and six replicates per treatment. By completing 24 hours after slaughter, it evaluated muscle conformation and degree of finish made the longissimus dorsi at the 13th rib. A representative sample between the 10th and 12th ribs was collected for evaluation of the physical components of carcasses. As well as the other variables, the hot carcass weight, dressing percentage, carcass length and rib eye area were not influenced by different pie levels in feed. The mean percentage of muscle, bone and fat from the carcass were 53.45; 16.14 and 29.46%, respectively, similar among treatments. Therefore, the use of up to 600 g kg-1 of sunflower pie replacing cottonseed meal as the main protein source, did not affect the carcass characteristics and meat quality of Nelore heifers.

  14. 77 FR 8717 - Dairy Product Mandatory Reporting

    Science.gov (United States)

    2012-02-15

    ... Marketing Service 7 CFR Part 1170 RIN 0581-AD12 Dairy Product Mandatory Reporting AGENCY: Agricultural... manufacturers of dairy products to report sales information for a mandatory dairy product reporting program. The... for this final rule. Background: The Dairy Product Mandatory Reporting Program, 7 CFR part 1170,...

  15. The comparison of dairy performance and some reproductive parameters of holstein cows imported from Sweden and their Polish age mates

    Directory of Open Access Journals (Sweden)

    Ewa Czerniawska-Piątkowska

    2007-01-01

    Full Text Available The general aim of the present work was to compare dairy performance and some reproductive parameters of Holstein-Friesian (HF cows imported from Sweden as an in-calf heifers, and their age mates in Poland. The animals were kept freely on the deep litter on the farm owned by Agro-company “Witkowo” and feeding was based on TMR (total mixed ration system during whole year. All ration’s ingredients (bulky feed, concentrate, miscellaneous additives were mixed and fed as all-mash. The feed ration depended from the physiological condition of a cow and it was composed of corn and grass ensilage, mash concentrate, crushed corn meal, brewer’s grains and beet pulp.Cows imported from Sweden as in-calf heifers obtained higher milk, fat and protein yield in both lactations comparing to home cows. Significant statistical differences were observed for kg of milk, kg of protein, for FCM (P<0.01 and for kg of fat (P<0.05 in 2nd lactation. Fat and protein content in milk was in average higher for home cows (P<0.01. Big differences (P<0.01 were observed in SBT (proportion of protein to fat content and RTB (difference between concentration of fat and protein at imported cows in 2nd lactation. As far as reproduction parameters (gestation interval, calving interval, insemination index are concerned was cows from Sweden better too. Heifers from Sweden calved earlier. The usage of high genetic potential of imported cows is possible only with providing them optimum living conditions suitable to their needs.

  16. A field investigation of a modified intravaginal progesterone releasing device and oestradiol benzoate based ovulation synchronisation protocol designed for fixed-time artificial insemination of Brahman heifers.

    Science.gov (United States)

    Edwards, S A A; Boe-Hansen, G B; Satake, N; Chandra, K; McGowan, M R

    2015-09-01

    Pregnancy rates (PR) to fixed-time AI (FTAI) in Brahman heifers were compared after treatment with a traditional oestradiol-based protocol (OPO-8) or a modified protocol (OPO-6) where the duration of intravaginal progesterone releasing device (IPRD) was reduced from 8 to 6 days, and the interval from IPRD removal to oestradiol benzoate (ODB) was increased from 24 to 36 h. Rising 2 yo heifers on Farm A: (n = 238 and n = 215; two consecutive days AI); B (n = 271); and C (n = 393) were allocated to OPO-8 or OPO-6. An IPRD was inserted and 1mg ODB i.m. on Day 0 for OPO-8 heifers and Day 2 for OPO-6 heifers. On Day 8, the IPRD was removed and 500 μg cloprostenol i.m. At 24h, for OPO-8 heifers, and 36 h, for OPO-6 heifers, post IPRD removal all heifers received 1mg ODB i.m. FTAI was conducted at 54 and 72 h post IPRD removal for OPO-8 and OPO-6 heifers. At Farm A, OPO-6 heifers, AI on the second day, the PR was 52.4% to FTAI (P = 0.024) compared to 36.8% for OPO-8 heifers. However, no differences were found between OPO-8 and OPO-6 protocols at Farm A (first day of AI) (39.9 vs. 35.7%), or Farms B (26.2 vs. 35.4%) and C (43.2% vs. 40.3%). Presence of a corpus luteum at IPRD insertion affected PR to FTAI (43.9% vs. 28.8%; P < 0.001). This study has shown that the modified ovulation synchronisation protocol OPO-6 may be a viable alternative to the OPO-8 protocol for FTAI in B. indicus heifers. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Effect of Exposure to Various Durations of Light on Serum Insulin-Like Growth Factor-I in Prepubertal Holstein Heifers

    Directory of Open Access Journals (Sweden)

    L. J. Spicer

    2007-01-01

    Full Text Available Our objective was to determine if prolonged exposure to various durations of light (i.e., photoperiod would affect serum IGF-I concentrations in heifers. Thus, 16 Holstein heifers, 2 to 4 mo of age, were exposed during a 5-wk pretreatment period to 12 h of cool-white fluorescent light (L at an intensity of 1200 lux and 12 h of dark (D. At 5 wk, photoperiods were adjusted to 24 L: 0 D (24 L, 20 L: 4 d (20 L, 16 L: 8 D (16 L or 8 L: 16 D (8 L per 24 h (n=4 heifers per photoperiod treatment. Blood was sampled at 5 wk and monthly for 4 mo. During each sampling period, blood was collected at 16-h intervals for 48 h and serum IGF-I was determined by RIA. Photoperiod treatment, month of experiment and their interactions affected serum IGF-I concentrations. Averaged over months, concentrations of serum IGF-I was greatest in heifers on 16 L; heifers on 20 L had IGF-I concentrations similar to 8 L, 16 L and 24 L and heifers on 24 L had concentrations similar to that of heifers on 8 L. Heifers in all treatment groups exhibited an increase in serum IGF-I concentration during the 4 mo of treatment. Heifers on 16 L and 20 L exhibited the greatest difference in serum IGF-I concentrations compared with 8L heifers after 3 mo of treatment. In conclusion, 16 L increases concentrations of serum IGF-I above that seen for heifers treated with

  18. Test accuracy at different cut-offs when plasma concentrations of metabolic indicators are used to detect decreased fertility in dairy cows (Poster topic 01, Poster 27, p. 193)

    DEFF Research Database (Denmark)

    Lomander, H; Gustafsson, H; Svensson, C

    Negative energy balance is a known risk factor for decreased fertility in dairy cows. This study evaluates the accuracy of measuring plasma concentrations of two indicators of negative energy balance, non esterified fatty acids (NEFA) and β-hyrdroxy buturate (BHBA), when they are used to predict...... the test was used in heifers compared to older cows. With a prevalence of ANEST of 28% PV+ were 0.25 and PV- nearly 0.90. With a DFAI prevalence of 35%, PV+ were indicate that overall test performance is low when metabolic indicators measured 0-21 days in milk...

  19. Effects of circulating progesterone and insulin on early embryo development in beef heifers.

    Science.gov (United States)

    Mann, G E; Green, M P; Sinclair, K D; Demmers, K J; Fray, M D; Gutierrez, C G; Garnsworthy, P C; Webb, R

    2003-11-20

    The aims of this study were to determine the effect on early embryo development of feeding a diet formulated to enhance circulating insulin concentrations and secondly to investigate the association between early embryo development and maternal progesterone concentrations in beef heifers. The study was carried out in 32 Simmental x Holstein Friesian heifers 22-25 months of age weighing 506+/-7kg and in condition score 3.1+/-0.1. Animals were fed two diets that were isoenergetic and isonitrogenous, but that would encourage either propionate (diet A) or acetate (diet B) production in the rumen. The rationale was that propionate would induce a greater insulin release in response to feeding. Animals were fed a 50:50 mix of the two diets for 14 days at 0.8x maintenance, with straw provided ad libitum. Animals were then fed one of the experimental diets for 3 weeks prior to synchronisation of oestrus and insemination and for a further 16 days following mating. All heifers were blood sampled daily from oestrus synchronisation and eight animals on each diet underwent daily transrectal real-time ultrasonography to determine the day of ovulation. All heifers were slaughtered at Day 16 after mating. While feeding of diet A (propionic) caused a significant (Pbody condition making further increases in insulin difficult to achieve. Diet did not affect size of ovulatory follicle (DIET A: 15.1+/-0.7mm; diet B: 14.6+/-0.7mm), day of ovulation (diet A: 3.5+/-0.2 days; diet B: 3.4+/-0.2 days), mean plasma progesterone concentration (diet A: 4.7+/-0.4ng/ml; diet B: 5.2+/-0.3ng/ml), corpus luteum weight (diet A: 6.0+/-0.2g; diet B: 6.0+/-0.2g) or pregnancy rate (diet A: 81.3%; diet B: 81.3%). However, the proportion of well-elongated (>10cm) embryos on Day 16 was higher in animals fed diet A than in those fed diet B (84.6% versus 38.5%; P10cm) embryos with levels in these animals significantly higher on Days 4 and 5 than in heifers with small (embryos at slaughter. This study

  20. Effect of progesterone supplementation in the first week post conception on embryo survival in beef heifers.

    Science.gov (United States)

    Beltman, M E; Lonergan, P; Diskin, M G; Roche, J F; Crowe, M A

    2009-04-15

    Progesterone is essential for establishment and maintenance of pregnancy in mammals. The objective of this study was to examine the effect of elevating progesterone during the different physiological stages of early embryo development on embryo survival. Estrus was synchronized in cross-bred beef heifers (n=197, approximately 2-years old) and they were inseminated 12-18h after estrus onset (=Day 0). Inseminated heifers were randomly assigned to 1 of 3 treatments: (1) Control, n=69; (2) progesterone supplementation using a Controlled Internal Drug Release Device (CIDR) from Day 3 to 6.5, n=64; or (3) progesterone supplementation using a CIDR from Day 4.5 to 8, n=64. Body condition (BCS) and locomotion scores (scale of 1-5) were recorded for all animals. Animals with a locomotion score >/=4 (very lame) were excluded. Embryo survival rate was determined at slaughter on Day 25. Conceptus length and weight were recorded and the corpus luteum (CL) of all pregnant animals was dissected and weighed. Supplementation with exogenous progesterone increased (P<0.05) peripheral progesterone concentrations, but did not affect embryo survival rate compared with controls. Mean CL weight, conceptus length and conceptus weight were not different between treatments. There was a positive relationship (P<0.04) between the increase in progesterone concentrations from Days 3 to 6.5 and embryo survival rate in treated heifers and a similar trend existed between the increase from Days 4.5 to 8 (P<0.06). There was also a positive relationship (P<0.05) between the progesterone concentration on Day 6.5 and the embryo survival rate in treated heifers. A direct correlation was seen between locomotion score and embryo survival rate, with higher (P<0.05) early embryo survival rates in heifers with a lower locomotion score. In conclusion, supplementation with progesterone at different stages of early embryo development increased peripheral progesterone concentration and resulted in a positive

  1. Enteric methane emission, diet digestibility, and nitrogen excretion from beef heifers fed sainfoin or alfalfa.

    Science.gov (United States)

    Chung, Y-H; Mc Geough, E J; Acharya, S; McAllister, T A; McGinn, S M; Harstad, O M; Beauchemin, K A

    2013-10-01

    Effects of plant-bound condensed tannin (CT)-containing sainfoin vs. CT-free alfalfa (or low-CT alfalfa-sainfoin mixture), plant stage of maturity, and their interaction on enteric methane (CH4) emissions, diet digestibility, and N excretion were studied, using 8 ruminally cannulated beef heifers in 2 sequential short-term experiments (Exp. 1 and 2). In Exp. 1, first growth legumes were harvested daily and offered fresh to heifers. Heifers were assigned to 100% sainfoin or 80% alfalfa:20% sainfoin (as-fed basis). Responses were measured at early (late vegetative to early bud; stage 2 to 3) and late (early flower; stage 5) stage of maturity. In Exp. 2, the same legumes were harvested from second growth (late bud; stage 4) and offered to heifers as hay; 100% sainfoin or 100% alfalfa. In both experiments, heifers were fed once daily at 1× maintenance. When fed as fresh forage (Exp. 1), sainfoin, compared with the alfalfa-sainfoin blend, had greater digestibility of OM (74.7 vs. 70.9%; P = 0.02), yet tended to have lower CP digestibility (73.2 vs. 77.1%; P = 0.059). There was no difference between fresh legumes for CH4 emissions [25.9 g/kg DMI ± 4.02 SE; 8.5% of gross energy intake (GEI) ± 1.26 SE; or 36.8 g/kg digested OM ± 1.75 SE]. The fresh legumes were more digestible at early, rather than at late, maturity and, consequently, enteric CH4 (27.4 vs. 24.4 g/kg DMI; P emissions (22.4 g/kg DMI ± 1.29 SD and 7.1% GEI ± 0.40 SD). However, on the basis of OM digested, CH4 emissions were lower for sainfoin than alfalfa hay (44.3 vs. 59.0 g/kg; P = 0.008). Percentage of total N excretion in urine was less for sainfoin compared with alfalfa, both for fresh legumes in Exp. 1 (74 vs. 78%; P = 0.017) or hay in Exp. 2 (64 vs. 72%; P emissions from beef cattle fed at maintenance as compared with feeding either 80% alfalfa:20% sainfoin (fresh forages) or 100% alfalfa (hay). Feeding fresh legumes harvested between the late vegetative to early bud stage, compared with

  2. Hantavirus reservoir Oligoryzomys longicaudatus spatial distribution sensitivity to climate change scenarios in Argentine Patagonia

    Directory of Open Access Journals (Sweden)

    González Paula LM

    2009-07-01

    Full Text Available Abstract Background Oligoryzomys longicaudatus (colilargo is the rodent responsible for hantavirus pulmonary syndrome (HPS in Argentine Patagonia. In past decades (1967–1998, trends of precipitation reduction and surface air temperature increase have been observed in western Patagonia. We explore how the potential distribution of the hantavirus reservoir would change under different climate change scenarios based on the observed trends. Methods Four scenarios of potential climate change were constructed using temperature and precipitation changes observed in Argentine Patagonia between 1967 and 1998: Scenario 1 assumed no change in precipitation but a temperature trend as observed; scenario 2 assumed no changes in temperature but a precipitation trend as observed; Scenario 3 included changes in both temperature and precipitation trends as observed; Scenario 4 assumed changes in both temperature and precipitation trends as observed but doubled. We used a validated spatial distribution model of O. longicaudatus as a function of temperature and precipitation. From the model probability of the rodent presence was calculated for each scenario. Results If changes in precipitation follow previous trends, the probability of the colilargo presence would fall in the HPS transmission zone of northern Patagonia. If temperature and precipitation trends remain at current levels for 60 years or double in the future 30 years, the probability of the rodent presence and the associated total area of potential distribution would diminish throughout Patagonia; the areas of potential distribution for colilargos would shift eastwards. These results suggest that future changes in Patagonia climate may lower transmission risk through a reduction in the potential distribution of the rodent reservoir. Conclusion According to our model the rates of temperature and precipitation changes observed between 1967 and 1998 may produce significant changes in the rodent

  3. Hydrological cycles and trends in the NW Argentine Andes since 1940

    Science.gov (United States)

    Castino, Fabiana; Bookhagen, Bodo; Strecker, Manfred

    2016-04-01

    Strong spatiotemporal variability characterizes the hydrometeorological pattern in the NW Argentine Andes, draining parts of the most populated and economically important areas of South America. During the summer monsoon season (DJF), the eastern flanks of the central Andes are characterized by deep convection, exposing them to extreme hydrometeorological events. These often result in floods and landslides with disastrous effects on the local populations. Here, we analyze river discharge to explore long-term hydrological variability in NW Argentine Andes and the linked climate controlling processes. We rely on 13 daily river discharge time series relevant to drainage basins spanning several size orders (102-104 km2) starting in 1914 and define different hydro-climate indices both for the mean and the extreme hydrological events. We apply quantile regression to investigate long-term trends and spectral analysis associated with cross-correlation with SST-based climate indices to identify links to large-scale climate variability modes. River discharge presents a pronounced and coherent variability signal in South America, particularly for wide drainage basins, such as the Amazon and Paraná/La Plata rivers, strongly associated to Pacific and Atlantic Oceans Sea Surface Temperature (SST) anomalies (i.e. ENSO, PDO, AMO). Our analysis evidences that in the NW Argentine Andes, mean discharge values are characterized by statistically significant, mostly positive, long-term trends since 1940, whereas the extreme events present a more non-unidirectional trend pattern. Also, coherent multi-annual to multi-decadal cycles characterizing the discharge pattern have been identified, suggesting that processes linked to SST anomaly-modes strongly control the hydrometeorology variability in the NW Argentina Andes.

  4. Plasticity in queen number and social structure in the invasive Argentine ant (Linepithema humile).

    Science.gov (United States)

    Ingram, Krista K

    2002-10-01

    In many polygynous social insect societies, ecological factors such as habitat saturation promote high queen numbers by increasing the cost of solitary breeding. If polygyny is associated with constrained environments, queen number in colonies of invasive social insects should increase as saturation of their new habitat increases. Here I describe the variation in queen number, nestmate relatedness, and nest size along a gradient of time since colonization in an invading population of Argentine ants (Linepithema humile) in Haleakala, Hawaii. Nest densities in this population increase with distance from the leading edge of the invasion, reaching a stable density plateau approximately 80 m from the edge (> 2 years after colonization). Although the number of queens per nest in Haleakala is generally lower than previously reported for Argentine ants, there is significant variation in queen number across this population. Both the observed and effective queen numbers increase across the density gradient, and nests in the center of the population contain queen numbers three to nine times higher than those on the edge of the invasion. The number of workers per nest is correlated with queen number, and nests in the center are six times larger than nests at the edge. Microsatellite analysis of relatedness among nestmates reveals that all nests in the Haleakala population are characterized by low relatedness and have evidence of multiple reproducing queens. Relatedness values are significantly lower in nests in the center of the population, indicating that the number of reproducing queens is greater in areas of high nest density. The variation in queen number and nestmate relatedness in this study is consistent with expectations based on changes in ecological constraints during the invasion of a new habitat, suggesting that the social structure of Argentine ant populations is strongly influenced by ecological factors. Flexibility in social structure may facilitate persistence

  5. ``You are what you eat'': Diet modifies cuticular hydrocarbons and nestmate recognition in the Argentine ant, Linepithema humile

    Science.gov (United States)

    Liang, D.; Silverman, J.

    2000-10-01

    Nestmate recognition plays a key role in the behavior and evolution of social insects. We demonstrated that hydrocarbons are the chemical cues used in Argentine ant, Linepithema humile, nestmate recognition, and that these hydrocarbons can be acquired from insect prey. Consequently, Argentine ant cuticular hydrocarbon patterns reveal the same hydrocarbons present in their diet. Diet alters both the recognition cues present on the cuticular surface and the response of nestmates to this new colony odor, resulting in aggression between former nestmates reared on different insect prey.

  6. "You are what you eat": diet modifies cuticular hydrocarbons and nestmate recognition in the Argentine ant, Linepithema humile.

    Science.gov (United States)

    Liang, D; Silverman, J

    2000-09-01

    Nestmate recognition plays a key role in the behavior and evolution of social insects. We demonstrated that hydrocarbons are the chemical cues used in Argentine ant, Linepithema humile, nestmate recognition, and that these hydrocarbons can be acquired from insect prey. Consequently, Argentine ant cuticular hydrocarbon patterns reveal the same hydrocarbons present in their diet. Diet alters both the recognition cues present on the cuticular surface and the response of nestmates to this new colony odor, resulting in aggression between former nestmates reared on different insect prey.

  7. Haematological profile of crossbred dairy cattle to monitor herd health status at medium elevation in Central Himalayas.

    Science.gov (United States)

    Kumar, B; Pachauri, S P

    2000-10-01

    Haematological profile-haemoglobin concentration (Hb), total erythrocytes count (TEC), packed cell volume (PCV), erythrocyte indices-mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were studied in crossbred dairy cattle (Holstein Friesian x Sahiwal) under various physiological states: non-pregnant heifers (NPH), pregnant heifers (PH), empty dry cows (EDC), pregnant lactating cows (PLC), medium yield early lactating cows (MYELC) and high yield early lactating cows (HYELC) during summer and winter seasons at 1700 metres altitude from mean sea level in the Central Himalayas. On comparison of annual means, the highest values of Hb and PCV were recorded in PH and of TEC in NPH, whereas the lowest values of these parameters were found in EDC. The Hb and TEC tended to decrease with increasing milk yield. Comparison of annual means of erythrocyte indices revealed the highest MCV and MCH in EDC, which simultaneously showed the lowest MCHC. Significant seasonal variations in haematological profile were recorded. The overall group mean (OGM) of Hb, MCV, MCH and MCHC was found to be significantly higher (P OGM (P < 0.01) during the winter season.

  8. A new species of Havelockia Pearson, 1903 from the Argentine Sea (Holothuroidea: Dendrochirotida: Sclerodactylidae).

    Science.gov (United States)

    Martinez, Mariano I; Thandar, Ahmed S; Penchaszadeh, Pablo E

    2013-02-04

    Havelockia pegi sp. nov., is here described from shallow waters of the Argentine Sea. This new species is distinctive in the purple colouration of its tentacles, scarcity of body wall ossicles and the presence of rosette-shaped ossicles in both the introvert and the tentacles. It is not closely related to any of its congenors. This is the first record of a true sclerodactylid from Argentina. Thandarum hernandezi Martinez & Brogger, 2012, described in the family Sclerodactylidae, is now classified in the family Sclerothyonidae.

  9. Graphic correlation of Argentine Precordillera and North American Lower/Middle Ordovician sections

    Institute of Scientific and Technical Information of China (English)

    Walter C.Sweet; Guillermo L.Albanesi

    2006-01-01

    @@ Present work demonstrates that a level equivalent to the proposed Whiterockian basal GSSP can be located graphically in a composite section anchored by the Niquivil section of the Argentine Precordillera. The FAD of Cooperignathus aranda in the Niquivil composite section, a candidate for GSSP of the Lower/Middle Ordovician boundary, projects to a level very close to the FAD of Tripodus laevis in the Whiterockian reference section. The conodont-based framework reported here includes the potential for recognition of the proposed Whiterock Canyon-based GSSP, the Cooperignathus aranda-based GSSP, and, possibly, the Baltoniodus triangularisbased GSSP, recently proposed.

  10. The argentine territory as an international venue for the administration of punishment

    OpenAIRE

    Argenti, Natalia

    2014-01-01

    El objetivo principal de este trabajo es poner de relieve los múltiples problemas que deberían afrontarse para que las cárceles argentinas administren las penas de acuerdo con el Estatuto de Roma (art. 103). La propuesta tiene eficacia cuantificable en términos del tratamiento humanitario de los reos y promueve, en general, el ejercicio de sus derechos más vitales y básicos. The primary goal of this work is to highlight the various problems that should be addressed so that Argentine prison...

  11. The widespread collapse of an invasive species: Argentine ants (Linepithema humile) in New Zealand

    OpenAIRE

    2011-01-01

    Synergies between invasive species and climate change are widely considered to be a major biodiversity threat. However, invasive species are also hypothesized to be susceptible to population collapse, as we demonstrate for a globally important invasive species in New Zealand. We observed Argentine ant populations to have collapsed in 40 per cent of surveyed sites. Populations had a mean survival time of 14.1 years (95% CI = 12.9–15.3 years). Resident ant communities had recovered or partly re...

  12. The first study of the micro-fauna of middle Cambrian olistoliths in the Argentine Precordillera

    OpenAIRE

    Fahlgren, Elise; Tranvik, Maria

    2015-01-01

    This study implies a survey of a somewhat unexplored Cambrian carbonate formation in the Argentine Precordillera (AP) located in western Argentina, close to the city of San José de Jáchal. The carbonate platform of the AP is a unique piece of the South American geology and is in this study partly surveyed and compared with the Stephen Formation of northern Canada, a middle Cambrian unit renowned for its contents of exceptionally well preserved soft bodied fossils named the Burgess Shale biota...

  13. Equity during an economic crisis: financing of the Argentine health system.

    Science.gov (United States)

    Cavagnero, Eleonora; Bilger, Marcel

    2010-07-01

    This article analyses the redistributive effect caused by health financing and the distribution of healthcare utilization in Argentina before and during the severe 2001/2002 economic crisis. Both dramatically changed during this period: the redistributive effect became much more positive and utilization shifted from pro-poor to pro-rich. This clearly demonstrates that when utilization is contingent on financing, changes can occur rapidly; and that an integrated approach is required when monitoring equity. From a policy perspective, the Argentine health system appears vulnerable to economic downturns mainly due to high reliance on out-of-pocket payments and the strong link between health insurance and employment.

  14. Complete mitochondrial genome of the argentine ant, Linepithema humile (Hymenoptera: Formicidae).

    Science.gov (United States)

    Zhao, Ezi; Bi, Guiqi; Yang, Junqing; Zhang, Zhen; Liu, Guoqiang; Du, Qingwei; Shang, Erlei

    2017-03-01

    In this study, the complete mitochondrial genome of the widespread invasive Argentine ant (Linepithema humile) was first determined. The mitochondrial genome is 16 098 bp in length, and encodes one D-loop region, two ribosomal RNA genes, 13 protein-coding genes, and 18 transfer RNA genes. Average GC content of this genome is 19.68%. nad6 and cob genes were overlapped by 4 bp. The phylogenetic tree involving 13 available closely related species further validated the new determined sequences and phylogeny of L. humile.

  15. Evaluation of steroidogenic capacity after follicle stimulating hormone stimulation in bovine granulosa cells of Revalor 200® implanted heifers

    Institute of Scientific and Technical Information of China (English)

    Andrea DStapp; Craig AGifford; Dennis MHallford; Jennifer AHernandez Gifford

    2014-01-01

    Background:Heifers not used as breeding stock are often implanted with steroids to increase growth efficiency thereby altering hormone profiles and potentially changing the environment in which ovarian follicles develop. Because bovine granulosa cell culture is a commonly used technique and often bovine ovaries are collected from abattoirs with no record of implant status, the objective of this study was to determine if the presence of an implant during bovine granulosa cell development impacts follicle stimulating hormone-regulated steroidogenic enzyme expression. Paired ovaries were collected from 16 feedlot heifers subjected to 1 of 3 treatments:non-implanted (n=5), Revalor 200 for 28 d (n=5), or Revalor 200 for 84 d (n=6). Small follicle (1 to 5 mm) granulosa cells were isolated from each pair and incubated with phosphate buffered saline (n=16) or 100 ng/mL follicle stimulating hormone (n=16) for 24 h. Results:Granulosa cells of implanted heifers treated with follicle stimulating hormone produced medium concentrations of progesterone similar (P=0.22) to non-implanted heifers, while medium estradiol concentrations were increased (P<0.10) at 28 and 84 d compared to non-implanted heifers indicating efficacy of treatment. Additionally, real-time PCR analysis in response to follicle stimulating hormone treatment demonstrated a decrease in steroidogenic acute regulatory protein (P=0.05) mRNA expression in heifers implanted for 84 d and an increase in P450 side chain cleavage mRNA in granulosa cells of heifers implanted for 28 (P<0.10) or 84 d (P<0.05) compared to non-implanted females. However, no difference in expression of 3-beta-hydroxysteroid dehydrogenase (P=0.57) and aromatase (P=0.23) were demonstrated in implanted or non-implanted heifers. Conclusions:These results indicate follicles which develop in the presence of high concentrations of androgenic and estrogenic steroids via an implant tend to demonstrate an altered capacity to respond to follicle

  16. The impact of dystocia on dairy calf health, welfare, performance and survival.

    Science.gov (United States)

    Barrier, A C; Haskell, M J; Birch, S; Bagnall, A; Bell, D J; Dickinson, J; Macrae, A I; Dwyer, C M

    2013-01-01

    Up to one-third of dairy calves are born after dystocia and this is a major cause of calf mortality. This study investigated the neonatal physiology, survival, health and subsequent growth of dairy calves following dystocia and is the first longitudinal study to analyse multiple effects and to look beyond the perinatal period. A total of 455 live born Holstein calves (N: No assistance, n=360; FN: Farmer assistance but normally presented calf, n=82; FM: Farmer assistance of malpresented calf, n=13) were followed from birth to first service (heifers) or until leaving the farm (bulls). Compared to N calves, FN and FM animals had higher salivary cortisol concentrations at day 1 (PDystocia had no biologically significant impact on rectal temperature throughout the first 4 days (P>0.05). During the first 60 days, FM calves had a higher proportion of days with non-routine health treatments (Pdystocia category (P>0.05). Calves which survive dystocia experience lower passive immunity transfer, higher mortality and higher indicators of physiological stress. Such calves have poorer welfare in the neonatal period and possibly beyond. Strategies need to be implemented to improve the subsequent health and welfare of such calves and to lower the incidence of dystocia.

  17. Effects of defaunation and dietary coconut oil distillate on fermentation, digesta kinetics and methane production of Brahman heifers.

    Science.gov (United States)

    Nguyen, S H; Hegarty, R S

    2016-07-06

    A 2 × 2 factorial experiment was conducted to assess the effects of presence or absence of rumen protozoa and of dietary coconut oil distillate (COD) supplementation on rumen fermentation characteristics, digesta kinetics and methane production in Brahman heifers. Twelve Brahman heifers were selected to defaunate, with 6 being subsequently refaunated. After defaunation and refaunation, heifers were randomly allocated to COD supplement or no supplement treatments while fed an oaten chaff-based diet. Methane production (MP; 94.17 v 104.72 g CH4 /d) and methane yield [MY; 19.45 v 21.64 g CH4 /kg dry matter intake (DMI)] were reduced in defaunated heifers compared with refaunated heifers when measured at 5 weeks after refaunation treatment (p  0.05). The results confirmed that defaunation and COD independently reduced enteric MP even though the reduced emissions were achieved without altering rumen fermentation VFA levels or gut digesta kinetics. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  18. EFFECT OF LEVEL OF CONCENTRATE SUPPLEMENTATION ON GROWTH RATE AND AGE AT MATURITY IN GROWING BUFFALO HEIFERS

    Directory of Open Access Journals (Sweden)

    M. RAFIQ, M. A. CHAUDHRY AND M. A. JABBAR

    2008-01-01

    Full Text Available This study was conducted to observe the effect of supplementation of concentrate mixture alongwith green fodder on growth rate and age of maturity in growing buffalo heifers. Twenty seven heifers of Nili-Ravi buffalo, with 18-21 months of age and on an average 280.0 Kg body weight, were randomly divided into three groups A, B and C, with 9 animals in each group. All the groups were given chaffed green fodder ad lib. on group feeding basis. In addition, heifers of groups A and B were given 2.0 and 4.0 kg of concentrate mixture per head per day, while the group C received no concentrate and was kept as control. Daily green fodder consumption was 32.5, 30.00 and 37.50 Kg, with a growth rate of 0.558, 0.659 and 0.354 Kg in groups A, B and C, respectively. The age at maturity averaged 774, 728 and 993 days, while body weights were 411, 431 and 388 Kg in respective groups. The results revealed that the maturity age was significantly reduced (P<0.01 by concentrate supplementation compared with fodder alone. Cost of rearing of buffalo heifers up to age of maturity was 5829.00, 6862.00 and 8747.00 rupees in respective groups. Rearing of buffalo heifers on green fodder ad lib. alongwith supplementation of 2 Kg of concentrate mixture was economical.

  19. Laminitis and dermatitis in heifers associated with excessive carbohydrate intake : skin lesions and biochemical findings : case report

    Directory of Open Access Journals (Sweden)

    I. Yeruham

    1999-07-01

    Full Text Available The effects of a sudden addition of a large quantity of readily fermentable carbohydrate to the feed ration of pregnant heifers are described. Clinical and pathological changes caused by the resulting disease were confined to the digits and skin. The 4 acutely affected heifers were reluctant to get up or move (group II. They tended to lie down or stand with feet bunched together and the back arched, often shifting weight from limb to limb. They walked stiffly with great tenderness and pain in the digits. Extreme pain was noticed when the digits were examined. In 4 of 8 heifers, separation of the sole at the heel, with leakage of exudate, and under-running of the sole were observed. Necrotic dermatitis of the legs, alopecia and hyperkeratosis of the tail were noticed in all 8 heifers. Skin lesions appeared simultaneously. Four of the heifers (group I recovered, and the other 4 (group II were sent to slaughter. No post mortem examination was performed. The biochemical findings revealed a significantly higher concentration of total serum globulins and sodium, and increased activity, in CK, LDH and AST. A significantly decreasing pattern was noted in blood urea concentration, cholesterol, triglycerides, albumin and calcium. No significant differences among the various groups were found in the activities of amylase, GGT, and concentration of creatinine, total bilirubin, inorganic phosphorus, magnesium and potassium.

  20. Function of the corpus luteum in beef heifers is affected by acute submaintenance feeding but is not correlated with residual feed intake

    Science.gov (United States)

    Seventy-four Angus and Angus x Hereford heifers were used in two successive years (yr 1, n = 43; yr 2, n = 31) to determine if ovarian function of heifers during acute submaintenance feeding is related to variation in utilization of feed as determined by residual feed intake (RFI). Residual feed in...

  1. Gene network analyses of first service conception in Brangus heifers: Use of genome and trait associations, hypothalamic-transcriptome information, and transcription factors

    Science.gov (United States)

    Measures of heifer fertility are economically relevant traits for beef production systems and knowledge of candidate genes could be incorporated into future genomic selection strategies. Ten traits related to growth and fertility were measured in 890 Brangus heifers (3/8 Brahman × 5/8 Angus, from 6...

  2. Relationships between milking frequency, lactation persistency and milk yield in Sweish Red heifers and cows milked in a voluntary attendance automatic milking system

    DEFF Research Database (Denmark)

    Pettersson, Gunnar; Svvenersten-Sjaunja, Kerstin; Knight, Christopher Harold

    2011-01-01

    and lactation persistency and total lactation yield were determined. Cows had higher peak and total milk yields than heifers, but heifers had higher persistency (defined as the rate of decline in milk yield between days 100 and 300 post calving). Milking frequency did not differ significantly between cows...

  3. Evaluation of the innate immune response of Angus heifers with genetic marker variation for intramuscular fat deposition following a lipopolysaccharide challenge

    Science.gov (United States)

    This study evaluated the effect of genetic selection for markers related to marbling deposition in Angus heifers on the immune response following a lipopolysaccharide (LPS) challenge. Fall-born heifers (n = 19; ~7 months of age, 274 +/- 24 kg) with genetic variation for marbling were utilized inclu...

  4. Dehydrated citrus pulp alters feedlot performance of crossbred heifers during the receiving period and modulates serum metabolite concentrations pre- and post-endotoxin challenge

    Science.gov (United States)

    English x Continental heifers (n=180) were sourced in two loads (188.7 ± 18.0 kilograms and 225.2 ± 22.2 kilograms body weight, respectively) from commercial auction barns to study the effects of feeding dehydrated citrus pulp (DCP) on feedlot performance of newly received heifers. A completely ran...

  5. Relationships among performance, residual feed intake, and temperament assessed in growing beef heifers and subsequently as 3-year-old, lactating beef cows

    Science.gov (United States)

    Seventy-four beef heifers were used to evaluate the relationships among performance, residual feed intake (RFI), and temperament measured as growing heifers (Phase 1) and subsequently as 3-year-old lactating beef cows (Phase 2) in the same cohort. In both phases, females were housed in a covered fac...

  6. A longitudinal study into the effect of grazing on claw disorders in female calves and young dairy cows.

    Science.gov (United States)

    Holzhauer, M; Brummelman, B; Frankena, K; Lam, T J G M

    2012-09-01

    To estimate the prevalence of claw disorders in youngstock and first parity heifers and to evaluate the effect of grazing on claw disorders, 10 Dutch dairy herds participated in a 2-year longitudinal study. Five herds were zero-grazed, while in the other five herds cows and youngstock had access to pasture during the summer. Twenty female calves 15%. The prevalence of DD increased considerably around first calving on both the grazing and the zero-grazing farms. The prevalence of IDHE increased with age while SH prevalence showed a more fluctuating pattern. Digital dermatitis was less frequently observed in pastured animals than in permanently housed animals (OR=0.12-0.64 depending on month of observation; P<0.05), with the strongest effect being seen during the period when the herds which grazed cattle actually had animals at pasture (May to August). Grazing was also associated with lower levels of IDHE and SH, again particularly during the grazing season.

  7. Expression of androgen-producing enzyme genes and testosterone concentration in Angus and Nellore heifers with high and low ovarian follicle count.

    Science.gov (United States)

    Loureiro, Bárbara; Ereno, Ronaldo L; Favoreto, Mauricio G; Barros, Ciro M

    2016-07-15

    Follicle population is important when animals are used in assisted reproductive programs. Bos indicus animals have more follicles per follicular wave than Bos taurus animals. On the other hand, B taurus animals present better fertility when compared with B indicus animals. Androgens are positively related with the number of antral follicles; moreover, they increase growth factor expression in granulose cells and oocytes. Experimentation was designed to compare testosterone concentration in plasma, and follicular fluid and androgen enzymes mRNA expression (CYP11A1, CYP17A1, 3BHSD, and 17BHSD) in follicles from Angus and Nellore heifers. Heifers were assigned into two groups according to the number of follicles: low and high follicle count groups. Increased testosterone concentration was measured in both plasma and follicular fluid of Angus heifers. However, there was no difference within groups. Expression of CYP11A1 gene was higher in follicles from Angus heifers; however, there was no difference within groups. Expression of CYP17A1, 3BHSD, and 17BHSD genes was higher in follicles from Nellore heifers, and expression of CYP17A1 and 3BHSD genes was also higher in HFC groups from both breeds. It was found that Nellore heifers have more antral follicles than Angus heifers. Testosterone concentration was higher in Angus heifers; this increase could be associated with the increased mRNA expression of CYP11A1. Increased expression of androgen-producing enzyme genes (CYP17A1, 3BHSD, and 17BHSD) was detected in Nellore heifers. It can be suggested that testosterone is acting through different mechanisms to increase follicle development in Nellore and improve fertility in Angus heifers. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Prosecuting International Crimes at National Level: Lessons from the Argentine ‘Truth-Finding Trials’

    Directory of Open Access Journals (Sweden)

    Elena Maculan

    2012-01-01

    Full Text Available Truth-finding trials (juicios por la verdad constitute a novel solution devised by the Argentine judicial system to cope with crimes committed by the past military dictatorship. This mechanism uses criminal courts as well as criminal procedure in order to investigate the truth about the dictatorship's crimes; however, the trials allow judges neither to establish criminal responsibility nor to punish the perpetrators of crimes. This limitation is due to the inability, imposed by the Full Stop and Due Obedience Laws, to prosecute the perpetrators of crimes.From the perspective of criminal law, truth-finding trials present two problematic features: firstly, their creation and regulation are set by judges, which has caused the development of many non-homogeneous local solutions and, secondly, their hybrid nature, which entails a possible subversion of conventional forms and goals in the context of the criminal trial.The paper also describes the current situation, since the Argentine impunity laws were declared unconstitutional and criminal proceedings reopened. The new framework provokes questions about the relationship between the reopened criminal trials and the truth-finding investigations, not only with regard to evidentiary issues but also with respect to the reason why the truth-finding investigations are still held.Finally, the shift from a non-punitive approach to the current full criminal accountability seems to suggest that truth-finding trials were merely a temporary solution, while the notion of the full prosecution and punishment of State crimes was never really set aside.

  9. Development of virtual bait stations to control Argentine ants (Hymenoptera: Formicidae) in environmentally sensitive habitats.

    Science.gov (United States)

    Choe, Dong-Hwan; Vetter, Richard S; Rust, Michael K

    2010-10-01

    A novel bait station referred to as a virtual bait station was developed and tested against field populations of the invasive Argentine ant, Linepithema humile (Mayr) (Hymenoptera: Formicidae), at White Beach, Camp Pendleton, in Oceanside, CA. White Beach is a nesting habitat for an endangered seabird, the California least tern (Sterna antillarum browni Mearns). The beach is heavily infested with Argentine ants, one of the threats for the California least tern chicks. Conventional pest control strategies are prohibited because of the existence of the protected bird species and the site's proximity to the ocean. The bait station consisted of a polyvinyl chloride pipe that was treated on the inside with fipronil insecticide at low concentrations to obtain delayed toxicity against ants. The pipe was provisioned with an inverted bottle of 25% sucrose solution, then capped, and buried in the sand. Foraging ants crossed the treated surface to consume the sucrose solution. The delayed toxicity of fipronil deposits allowed the ants to continue foraging on the sucrose solution and to interact with their nestmates, killing them within 3-5 d after exposure. Further modification of the bait station design minimized the accumulation of dead ants in the sucrose solution, significantly improving the longevity and efficacy of the bait station. The virtual bait station exploits the foraging behavior of the ants and provides a low impact approach to control ants in environmentally sensitive habitats. It excluded all insects except ants, required only milligram quantities of toxicant, and eliminated the problem of formulating toxicants into aqueous sugar baits.

  10. Conflits et coopérations en territoire montagnard Mapuche (Argentine

    Directory of Open Access Journals (Sweden)

    Renaud Miniconi

    2010-03-01

    Full Text Available La question des autochtones est devenue, durant les deux dernières décennies, une préoccupation majeure dans différents pays du monde, comme en Argentine où environ 600 000 individus se reconnaissent comme tels, soit 1,5 % de sa population totale. Toutefois, ces populations sont encore trop souvent marginalisées à l’échelle de certaines régions, comme c’est le cas pour les Mapuche du Parc National Nahuel Huapi, situé dans les provinces du Rio Negro et de Neuquén. Si les textes internationaux et parfois nationaux réhabilitent certains droits humains essentiels de ces populations, les réalités locales sont plus contrastées, du fait d’intérêts souvent divergents des acteurs régionaux. Dans le contexte particulier d’une Argentine marquée par des difficultés d’accès à la propriété foncière pour une large part de la population, les parcs nationaux se révèlent être des outils pertinents, pour les populations autochtones, de recouvrement de leurs terres ancestrales, grâce en particulier aux processus de co-gestion participative mise en place sur ces territoires.

  11. Determination of TBT in water and sediment samples along the Argentine Atlantic coast.

    Science.gov (United States)

    de Waisbaum, R G; Rodriguez, C; Nudelman, N Sbarbati

    2010-11-01

    Cases of imposex have been reported for some organisms living in areas of the Argentine Atlantic coast. Since this is one of the known effects of the anti-fouling agent tributyltin (TBT), quantitative determinations of organotins in samples of water and sediments collected from sites along the Argentine coast were carried out. Severe cases of imposex were first reported for two gastropod species living in the Mar del Plata area, and determinations of TBT in samples collected from this site gave extremely high values and showed a close correlation between the degree of imposex and TBT concentration. Recent investigations in the area have shown a significant decrease. Surveys were also conducted in sites that exhibit highly irregular coastal profiles to examine the relevance of physical environments. Alarming concentrations of TBT were determined in most of the sites where heavy boat traffic and/or marine activities occur, demonstrating the urgent need for regulations to avoid further input of TBT. Reports from other sites in South America reveal that this should be a subject of regional concern in order to avoid severe damage to the biodiversity of regional marine organisms.

  12. Optimisation in a natural system: Argentine ants solve the Towers of Hanoi.

    Science.gov (United States)

    Reid, Chris R; Sumpter, David J T; Beekman, Madeleine

    2011-01-01

    Natural systems are a source of inspiration for computer algorithms designed to solve optimisation problems. Yet most 'nature-inspired' algorithms take only superficial inspiration from biology, and little is known about how real biological systems solve difficult problems. Moreover, ant algorithms, neural networks and similar methods are usually applied to static problems, whereas most biological systems have evolved to perform under dynamically changing conditions. We used the Towers of Hanoi puzzle to test whether Argentine ants can solve a potentially difficult optimisation problem. We also tested whether the ants can adapt to dynamic changes in the problem. We mapped all possible solutions to the Towers of Hanoi on a single graph and converted this into a maze for the ants to solve. We show that the ants are capable of solving the Towers of Hanoi, and are able to adapt when sections of the maze are blocked off and new sections installed. The presence of exploration pheromone increased the efficiency of the resulting network and increased the ants' ability to adapt to changing conditions. Contrary to previous studies, our study shows that mass-recruiting ant species such as the Argentine ant can forage effectively in a dynamic environment. Our results also suggest that novel optimisation algorithms can benefit from stronger biological mimicry.

  13. Nutrition and interference competition have interactive effects on the behavior and performance of Argentine ants.

    Science.gov (United States)

    Kay, Adam D; Zumbusch, Taylor; Heinen, Justa L; Marsh, Tom C; Holway, David A

    2010-01-01

    Food availability often influences competitive outcomes through effects on consumer growth. Although it has received less attention, food availability may also affect competition through nutritional effects on behavior. One hypothesis linking nutrition and competition in ants posits that increased access to carbohydrates favors greater investment in worker traits that underlie behavioral dominance. We tested this hypothesis by varying dietary protein:carbohydrate (P:C) ratios and levels of interspecific interference for Argentine ants (Linepithema humile), a widespread invasive species. As predicted, colonies facing interference increased patrolling more when reared on low P:C diets; this result is the first demonstration of an interactive effect of nutrition and interference on ant colonies. Several results suggest that this dietary effect on patrolling was due primarily to changes in colony size rather than worker behavior. Colonies on lower P:C diets had lower worker mortality and larger final colony sizes. Diet had little effect on per capita patrolling, and worker behavior in performance assays depended more on previous exposure to interference than on diet. Our findings indicate that dietary P:C ratios can influence Argentine ant performance in a competitive environment and suggest a mechanism by which monopolization of carbohydrate-rich resources can help invasive ants displace native ant competitors.

  14. Prosecuting International Crimes at National Level: Lessons from the Argentine ‘Truth-Finding Trials’

    Directory of Open Access Journals (Sweden)

    Elena Maculan

    2012-01-01

    Full Text Available Truth-finding trials (juicios por la verdad constitute a novel solution devised by the Argentine judicial system to cope with crimes committed by the past military dictatorship. This mechanism uses criminal courts as well as criminal procedure in order to investigate the truth about the dictatorship's crimes; however, the trials allow judges neither to establish criminal responsibility nor to punish the perpetrators of crimes. This limitation is due to the inability, imposed by the Full Stop and Due Obedience Laws, to prosecute the perpetrators of crimes.From the perspective of criminal law, truth-finding trials present two problematic features: firstly, their creation and regulation are set by judges, which has caused the development of many non-homogeneous local solutions and, secondly, their hybrid nature, which entails a possible subversion of conventional forms and goals in the context of the criminal trial.The paper also describes the current situation, since the Argentine impunity laws were declared unconstitutional and criminal proceedings reopened. The new framework provokes questions about the relationship between the reopened criminal trials and the truth-finding investigations, not only with regard to evidentiary issues but also with respect to the reason why the truth-finding investigations are still held.Finally, the shift from a non-punitive approach to the current full criminal accountability seems to suggest that truth-finding trials were merely a temporary solution, while the notion of the full prosecution and punishment of State crimes was never really set aside.

  15. The cycles of Argentine wine exports / Los ciclos de las exportaciones de vino argentinas

    Directory of Open Access Journals (Sweden)

    Cerdá Juan Manuel

    2016-01-01

    Full Text Available This paper analyses the different episodes that the Argentina wine industry transited between the years 1980 to 2012, within a context of globalization of the wine-grape industry. In particular, we study the significance that some winemakers had in the process and the effect of the exchange rate and recipients of Argentine wine in the expansion of exports in recent years. The hypothesis of this article is that, from the 80 s, the winemakers observed in exports as a solution to face their most important crisis. This required a transformation of the industry to produce quality wines that could be sold on the international market. Thus, winemakers added to a century-old winemaking tradition new practices and strategies. On the other hand, over 30 years, various macroeconomic policies affect the overall industry growth, especially in exports. On balance, in this paper we propose to show that the growth of exports of Argentine wine was a sinuous and different path to the literature has been found for the “new world” exporters countries. The data was obtained from Instituto Nancional de Vitivinícultura (INV, Bolsa de Comercio de Mendoza and International Organisation of Vine and Wine (OIV as well as interviews collected on primary and secondary sources.

  16. Geographical potential of Argentine ants (Linepithema humile Mayr) in the face of global climate change.

    Science.gov (United States)

    Roura-Pascual, Núria; Suarez, Andrew V; Gómez, Crisanto; Pons, Pere; Touyama, Yoshifumi; Wild, Alexander L; Peterson, A Townsend

    2004-12-22

    Determining the spread and potential geographical distribution of invasive species is integral to making invasion biology a predictive science. We assembled a dataset of over 1000 occurrences of the Argentine ant (Linepithema humile), one of the world's worst invasive alien species. Native to central South America, Argentine ants are now found in many Mediterranean and subtropical climates around the world. We used this dataset to assess the species' potential geographical and ecological distribution, and to examine changes in its distributional potential associated with global climate change, using techniques for ecological niche modelling. Models developed were highly predictive of the species' overall range, including both the native distributional area and invaded areas worldwide. Despite its already widespread occurrence, L. humile has potential for further spread, with tropical coastal Africa and southeast Asia apparently vulnerable to invasion. Projecting ecological niche models onto four general circulation model scenarios of future (2050s) climates provided scenarios of the species' potential for distributional expansion with warming climates: generally, the species was predicted to retract its range in tropical regions, but to expand at higher latitude areas.

  17. Single-stranded RNA viruses infecting the invasive Argentine ant, Linepithema humile.

    Science.gov (United States)

    Gruber, Monica A M; Cooling, Meghan; Baty, James W; Buckley, Kevin; Friedlander, Anna; Quinn, Oliver; Russell, Jessica F E J; Sébastien, Alexandra; Lester, Philip J

    2017-06-12

    Social insects host a diversity of viruses. We examined New Zealand populations of the globally widely distributed invasive Argentine ant (Linepithema humile) for RNA viruses. We used metatranscriptomic analysis, which identified six potential novel viruses in the Dicistroviridae family. Of these, three contigs were confirmed by Sanger sequencing as Linepithema humile virus-1 (LHUV-1), a novel strain of Kashmir bee virus (KBV) and Black queen cell virus (BQCV), while the others were chimeric or misassembled sequences. We extended the known sequence of LHUV-1 to confirm its placement in the Dicistroviridae and categorised its relationship to closest relatives, which were all viruses infecting Hymenoptera. We examined further for known viruses by mapping our metatranscriptomic sequences to all viral genomes, and confirmed KBV, BQCV, LHUV-1 and Deformed wing virus (DWV) presence using qRT-PCR. Viral replication was confirmed for DWV, KBV and LHUV-1. Viral titers in ants were higher in the presence of honey bee hives. Argentine ants appear to host a range of' honey bee' pathogens in addition to a virus currently described only from this invasive ant. The role of these viruses in the population dynamics of the ant remain to be determined, but offer potential targets for biocontrol approaches.

  18. Laboratory and Field Evaluations of Polyacrylamide Hydrogel Baits Against Argentine Ants (Hymenoptera: Formicidae).

    Science.gov (United States)

    Rust, Michael K; Soeprono, Andrew; Wright, Sarajean; Greenberg, Les; Choe, Dong-Hwan; Boser, Christina L; Cory, Coleen; Hanna, Cause

    2015-06-01

    The development of effective baits to control the Argentine ant, Linepithema humile (Mayr), has been problematic because foragers prefer sweet liquids, while many toxicants are insoluble in water and liquid baits are generally difficult to deliver. The incorporation of thiamethoxam and sucrose solutions into a water-absorbing polyacrylamide hydrogel provides a unique and novel carrier and method of application for liquid baits. Formulations of thiamethoxam affected the size of the hydrogels, and sucrose solutions containing 0.0003% technical thiamethoxam provided hydrogels as large as those made with 25% sucrose solution or deionized water. Concentrations of thiamethoxam as low as 0.000075% in the hydrogels provided 50% kill of workers within 3 d in a laboratory setting. In small colony studies, baiting with 0.00015 and 0.000075% thiamethoxam hydrogels provided 100% mortality of workers and queens within 8 d. An enzyme-linked immunosorbent assay indicated that thiamethoxam was absorbed into the interior of the polyacrylamide matrix. The water loss rates of the hydrogels were dependent upon the relative humidity. Polyacrylamide hydrogels with >50% water loss were less attractive to ants. Field studies in highly infested areas indicated that concentrations of 0.0006 or 0.0018% thiamethoxam were more effective than 0.00015%. Hydrogels may provide a cost-effective alternative to providing aqueous baits to control Argentine ants. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Quantitative analysis of the effects of the exotic Argentine ant on seed-dispersal mutualisms.

    Science.gov (United States)

    Rodriguez-Cabal, Mariano A; Stuble, Katharine L; Nuñez, Martin A; Sanders, Nathan J

    2009-08-23

    Although it is increasingly clear that exotic invasive species affect seed-dispersal mutualisms, a synthetic examination of the effect of exotic invasive species on seed-dispersal mutualisms is lacking. Here, we review the impacts of the invasive Argentine ant (Linepithema humile) on seed dispersal. We found that sites with L. humile had 92 per cent fewer native ant seed dispersers than did sites where L. humile was absent. In addition, L. humile did not replace native seed dispersers, as rates of seed removal and seedling establishment were all lower in the presence of L. humile than in its absence. We conclude that potential shifts in plant diversity and concomitant changes in ecosystem function may be a consequence of Argentine ant invasions, as well as invasions by other ant species. Because very few studies have examined the effects of non-ant invasive species on seed-dispersal mutualisms, the prevalence of disruption of seed-dispersal mutualisms by invasive species is unclear.

  20. Efficacy of Argentine propolis formulation for topical treatment of canine otitis externa

    Directory of Open Access Journals (Sweden)

    L.A Lozina

    2010-12-01

    Full Text Available The therapeutic effects of Argentine propolis ear drop formulation on canine otitis externa were evaluated. Forty-eight dogs with symptoms of otitis externa were randomly assigned to double-blinded, controlled clinical trial to evaluate the efficacy of topical formulation with propolis versus a topical placebo in the treatment of otitis externa. The propolis preparation and placebo were administrated into both external ear canals, twice daily for 14 days. Throughout the study, clinical examination and microbiological analysis of dogs ear exudates were made. The most frequent microorganisms isolated in culture media were: Malassezia pachydermatis (54.2%, Staphylococcus aureus (43.8%, coagulase-negative Staphylococcus (25.0%, Pseudomonas aeruginosa (20.8%, Candida albicans (18.8%, Proteus mirabilis (16.7%, Streptococcus spp. (16.7%, Enteroccocus faecalis (12.5%, Escherichia coli (12.5%, Staphylococcus intermedius (6.3%, Klebsiella spp. (4.2%, andCandida glabrata (2.1%. Whereas the control group did not recover from the infectious ear disease, the propolis preparation exhibited antimicrobial activity against most of the microorganisms isolated from samples of the treated group. In addition, no propolis-adverse effects were observed. This allowed propolis-treated patients to show a significant improvement of the clinical parameters. Thus, this new Argentine propolis ear drop formulation may be used for topical treatment of otitis externa in dogs.