Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo
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 or the consu......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...... or the consultant, and they were derived from expected cause-effect relations between technical performance and financial performance at the herd level. The study included the indicators shape of lactation curve, reproduction efficiency, heifer management, variation between cows in lactation curve persistency......, 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...
Kristensen, E; Ostergaard, S; Krogh, M A; Enevoldsen, C
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 or the consultant, and they were derived from expected cause-effect relations between technical performance and financial performance at the herd level. The study included the indicators shape of lactation curve, reproduction efficiency, heifer management, variation between cows in lactation curve persistency, 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 cow was analyzed as the measure of financial performance. The potential effects of the selected indicators on the gross margin were estimated by means of an ANOVA. The final model allowed estimation of the financial value of specific changes within the key performance indicators. This study indicated that improving the shape of the herd-level lactation curve by 1 quartile was associated with an increase in gross margin of euro 227 per cow year. This represents 53% of the additional available gross margin associated with all the management changes included in the study. The improved herd-level lactation curve 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" that used data extracted from ordinary management software to predict herd-specific financial performance related to major management changes. The metamodel was derived from
Schultz, K K; Bennett, T B; Nordlund, K V; Döpfer, D; Cook, N B
Transition cow management has been tracked via the Transition Cow Index (TCI; AgSource Cooperative Services, Verona, WI) since 2006. Transition Cow Index was developed to measure the difference between actual and predicted milk yield at first test day to evaluate the relative success of the transition period program. This project aimed to assess TCI in relation to all commonly used Dairy Herd Improvement (DHI) metrics available through AgSource Cooperative Services. Regression analysis was used to isolate variables that were relevant to TCI, and then principal components analysis and network analysis were used to determine the relative strength and relatedness among variables. Finally, cluster analysis was used to segregate herds based on similarity of relevant variables. The DHI data were obtained from 2,131 Wisconsin dairy herds with test-day mean ≥30 cows, which were tested ≥10 times throughout the 2014 calendar year. The original list of 940 DHI variables was reduced through expert-driven selection and regression analysis to 23 variables. The K-means cluster analysis produced 5 distinct clusters. Descriptive statistics were calculated for the 23 variables per cluster grouping. Using principal components analysis, cluster analysis, and network analysis, 4 parameters were isolated as most relevant to TCI; these were energy-corrected milk, 3 measures of intramammary infection (dry cow cure rate, linear somatic cell count score in primiparous cows, and new infection rate), peak ratio, and days in milk at peak milk production. These variables together with cow and newborn calf survival measures form a group of metrics that can be used to assist in the evaluation of overall transition period performance. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Magne, M A; Thénard, V; Mihout, S
Finding ways of increasing animal production with low external inputs and without compromising reproductive performances is a key issue of livestock systems sustainability. One way is to take advantage of the diversity and interactions among components within livestock systems. Among studies that investigate the influence of differences in animals' individual abilities in a herd, few focus on combinations of cow breeds with contrasting features in dairy cattle herds. This study aimed to analyse the performances and management of such multi-breed dairy cattle herds. These herds were composed of two types of dairy breeds: 'specialist' (Holstein) and 'generalist' (e.g. Montbeliarde, Simmental, etc.). Based on recorded milk data in southern French region, we performed (i) to compare the performances of dairy herds according to breed-type composition: multi-breed, single specialist breed or single generalist breed and (ii) to test the difference of milk performances of specialist and generalist breed cows (n = 10 682) per multi-breed dairy herd within a sample of 22 farms. The sampled farmers were also interviewed to characterise herd management through multivariate analysis. Multi-breed dairy herds had a better trade-off among milk yield, milk fat and protein contents, herd reproduction and concentrate-conversion efficiency than single-breed herds. Conversely, they did not offer advantages in terms of milk prices and udder health. Compared to specialist dairy herds, they produce less milk with the same concentrate-conversion efficiency but have better reproductive performances. Compared to generalist dairy herds, they produce more milk with better concentrate-conversion efficiency but have worse reproductive performances. Within herds, specialist and generalist breed cows significantly differed in milk performances, showing their complementarity. The former produced more milk for a longer lactation length while the latter produced milk with higher protein and fat
Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo
The manager of a dairy herd and the affiliated consultants constantly need to judge whether financial performance of the production system is satisfactory and whether financial performance relates to real (systematic) effects of changes in management. This is no easy task because the dairy herd...... is a very complex system. Thus, it is difficult to obtain empirical data that allows a valid estimation of the random (within-herd) variation in financial performance corrected for management changes. Thus, simulation seems to be the only option. This study suggests that much caution must be recommended...... when claming effect of changes in herd management because the link between management changes (cause) and effect (measured as improvement of gross margin per cow year) is extensively blurred by a large within-herd variation in available real life accounting data and differences between herds in time...
Background Overall reproductive performance of dairy herds is monitored by various indicators. Most of them do not consider all eligible animals and do not consider different management strategies at farm level. This problem can be alleviated by measuring the proportion of pregnant cows by specific intervals after their calving date or after a fixed time period, such as the voluntary waiting period. The aim of this study was to evaluate two reproductive performance indicators that consider the voluntary waiting period at the herd. The two indicators were: percentage of pregnant cows in the herd after the voluntary waiting period plus 30 days (PV30) and percentage of inseminated cows in the herd after the voluntary waiting period plus 30 days (IV30). We wanted to assess how PV30 and IV30 perform in a simulation of herds with different reproductive management and physiology and to compare them to indicators of reproductive performance that do not consider the herd voluntary waiting period. Methods To evaluate the reproductive indicators we used the SimHerd-program, a stochastic simulation model, and 18 scenarios were simulated. The scenarios were designed by altering the reproductive management efficiency and the status of reproductive physiology of the herd. Logistic regression models, together with receiver operating characteristics (ROC), were used to examine how well the reproductive performance indicators could discriminate between herds of different levels of reproductive management efficiency or reproductive physiology. Results The logistic regression models with the ROC analysis showed that IV30 was the indicator that best discriminated between different levels of management efficiency followed by PV30, calving interval, 200-days not-in calf-rate (NotIC200), in calf rate at100-days (IC100) and a fertility index. For reproductive physiology the ROC analysis showed that the fertility index was the indicator that best discriminated between different levels
Cláudio E. F. Cruz
Full Text Available Over the last decades, the emphasis on the health of dairy cows has changed from an individual to a herd level. In this scenario, the role played by the recording system and its interpretation by veterinarians has gained primordial importance. The records of productive and reproductive performance and of sanitary status from a southern Brazilian dairy cattle herd have been presented and discussed. The period of study was 2000-2009. Mean values per lactation period were 349D 8436M 290F 275P 201SCS (D: days in lactation, M: kg of milk yield, F: kg of fat, P: kg of protein and SCS: somatic cell score in 1000 cells/ml of milk. Major indexes of reproductive efficiency included age at first calving (31 months, services per conception (2.1, intercalving interval (428 days, calving to conception interval (146 days, mean annual rates of parturitions (76.2%, fetal losses (9.8-19.0%, and stillbirths (3.6%, apart of voluntary waiting period (94 days. Main information on sanitary status of the herd was associated with the mean prevalence of common disorders of dairy cattle such as anaplasmosis (29.8%, mastitis (27.8%, digital diseases (26.3%, ovarian cysts (21.3%, placental retention (19.7%, postpartum uterine infections (10.6%, and calf diarrhea (23.7% and pneumonia (16.8%, among others. In addition, culling reasons (low reproductive performance [56.3%] and udder/mastitis problems [33.6%], causes of cattle deaths (anaplasmosis [16.4%] and leukosis [11.4], and the impact of cattle diseases such as tuberculosis, leukosis, and neosporosis on the herd have also been presented and succinctly discussed. Numbers between brackets represent rates accumulated in the 10-year period.
In dairy herds, the interval between calving and pregnancy depend on many factors including preparation of the cow for calving, dietary management before and after calving. Factors such as hypocalcemia and body condition are determinant in the presentation of postpartum pathologies and ovarian activity resumption. Additionally, management of the dairy cattle should include fixed time artificial insemination protocols to increase the number of animals bred close to the voluntary waiting ...
Raaperi, Kerli; Bougeard, Stephanie; Aleksejev, Annely; Orro, Toomas; Viltrop, Arvo
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. 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. 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. 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.
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.
Mahaputra, L.; Hariadi, M.; Hardjopranjoto, S.
Studies involving 260 Friesian cows from three different locations were conducted to monitor the reproductive performance in small dairy herds in Indonesia by using milk progesterone RIA. In the first study 90 post-partum cows at three locations (Surabaya, Grati and Puspo) were used to investigate post-partum ovarian function. The highest incidence of cows not showing oestrus up to 80 days post-partum, with progesterone profiles less than 0.75 ng/mL, was found in Puspo (63.3%), compared with 10% in Surabaya and 20% in Grati. The incidence of cows with silent heat and oestrus without ovulation was 13.3 and 3.3% in Surabaya, 16.7 and 6.7% in Grati, and 23.3 and 0% in Puspo. There was no significant difference (P>0.05) between the lengths of oestrous cycles at the three different locations. In the second study, using 120 cows for investigating confirmation of oestrus at AI, 69.7% of cows inseminated during the follicular phase had become pregnant, compared with 16.1% of cows inseminated during the luteal phase. The incidence of long luteal phases which included embryonic death was 13.4%. The accuracy of pregnancy diagnosis based on progesterone concentrations at day 22 was 77% and was lower than that at day 29 (88%). In the third study, cows in Subgroups 3A and 3B had cystic ovaries and were treated with prostaglandin F 2α by either intramuscular (3A) or intrauterine (3B) routes. Pregnancy rates were 50 and 40%, respectively. Cows in Subgroups 3C, 3D and 3E had inactive ovaries and were treated with intravaginal application of MPA sponges (3C), PRID (3D) or PRID followed by LH injection (3E). The pregnancy rates were 30, 40 and 60%, respectively. (author). 10 refs, 6 tabs
A total of 1599 dairy records comprised of 710 calving interval and number of services per conception, and 179 age at first calving records were used to evaluate the performance of dairy cow kept at the University of Nairobi farm, Kanyariri, from 1989 to 2001. The data were analysed using fixed models with breed, year, ...
This thesis describes the execution, effects and economic benefits of veterinary herd health management (VHHM) programs on Dutch dairy farms. In chapter two, participants and non-participants in VHHM were asked for their opinions on VHHM. Important reasons for farmers to participate in VHHM were to
Agger, Jens F.; Christoffersen, Anna-Bodil; Rattenborg, Erik
During recent years in Denmark higher rates of antibodies to Coxiella burnetii have been detected in animals and humans than previously reported. A study based on bulk tank milk samples from 100 randomly selected dairy herds was performed to estimate the prevalence and geographical distribution...
Kalantari, A S; Cabrera, V E
The objective of this study was to determine the effect of reproductive performance on dairy cattle herd value. Herd value was defined as the herd's average retention payoff (RPO). Individual cow RPO is the expected profit from keeping the cow compared with immediate replacement. First, a daily dynamic programming model was developed to calculate the RPO of all cow states in a herd. Second, a daily Markov chain model was applied to estimate the herd demographics. Finally, the herd value was calculated by aggregating the RPO of all cows in the herd. Cow states were described by 5 milk yield classes (76, 88, 100, 112, and 124% with respect to the average), 9 lactations, 750 d in milk, and 282 d in pregnancy. Five different reproductive programs were studied (RP1 to RP5). Reproductive program 1 used 100% timed artificial insemination (TAI; 42% conception rate for first TAI and 30% for second and later services) and the other programs combined TAI with estrus detection. The proportion of cows receiving artificial insemination after estrus detection ranged from 30 to 80%, and conception rate ranged from 25 to 35%. These 5 reproductive programs were categorized according to their 21-d pregnancy rate (21-d PR), which is an indication of the rate that eligible cows become pregnant every 21 d. The 21-d PR was 17% for RP1, 14% for RP2, 16% for RP3, 18% for RP4, and 20% for RP5. Results showed a positive relationship between 21-d PR and herd value. The most extreme herd value difference between 2 reproductive programs was $77/cow per yr for average milk yield (RP5 - RP2), $13/cow per yr for lowest milk yield (RP5 - RP1), and $160/cow per yr for highest milk yield (RP5 - RP2). Reproductive programs were ranked based on their calculated herd value. With the exception of the best reproductive program (RP5), all other programs showed some level of ranking change according to milk yield. The most dramatic ranking change was observed in RP1, which moved from being the worst ranked
Haine, Denis; Delgado, Hector; Cue, Roger; Sewalem, Asheber; Wade, Kevin; Lacroix, René; Lefebvre, Daniel; Arsenault, Julie; Bouchard, Émile; Dubuc, Jocelyn
Several health disorders, such as milk fever, displaced abomasum, and mastitis, as well as impaired reproductive performance, are known risk factors for the removal of affected cows from a dairy herd. While cow-level risk factors are well documented in the literature, herd-level associations have been less frequently investigated. The objective of this study was to investigate the effect of cow- and herd-level determinants on variations in culling risk in Québec dairy herds: whether herd influences a cow's culling risk. For this, we assessed the influence of herd membership on cow culling risk according to displaced abomasum, milk fever, and retained placenta. A retrospective longitudinal study was conducted on data from dairy herds in the Province of Québec, Canada, by extracting health information events from the dairy herd health management software used by most Québec dairy producers and their veterinarians. Data were extracted for all lactations starting between January 1st and December 31st, 2010. Using multilevel logistic regression, we analysed a total of 10,529 cows from 201 herds that met the inclusion criteria. Milk fever and displaced abomasum were demonstrated to increase the cow culling risk. A minor general herd effect was found for the culling risk (i.e. an intra-class correlation of 1.0% and median odds ratio [MOR] of 1.20). The proportion of first lactation cows was responsible for this significant, but weak herd effect on individual cow culling risk, after taking into account the cow-level factors. On the other hand, the herd's average milk production was a protective factor. The planning and management of forthcoming replacement animals has to be taken into consideration when assessing cow culling risks and herd culling rates. Copyright © 2017 Elsevier B.V. All rights reserved.
Perrin, David J.; Schiefer, H. Bruno; Blakley, Barry R.
The addition of excessive copper to a commercially prepared dairy ration caused chronic copper toxicity in a dairy herd. A formulation error by a feed company resulted in copper levels of 800 to 1,000 mg/kg in the “as fed concentrate,” amounting to about 400-500 mg copper/kg of the whole ration. Five animals died with typical signs of acute copper toxicity, including intravascular hemolysis and methemoglobinemia. A further 39 cows died on the farm from a combination of debilitation and second...
Full Text Available Milk production performance of dairy buffaloes from 9 herds was evaluated. There were a total of 1,858 305D milk production records containing 13,219 milk test records from 1997 to 2006 available for evaluation. Records were analyzed with general linear model to determine the effect of season, parity and age at calving on standard 305D milk yield. Parity, season of calving and age at calving affected milk yield significantly. Average 305D milk production increased significantly from 864 kg in 1997 to 1244 kg in 2006. Genetic evaluation of milk production traits was also done using the same data set. The model for analysis is a multi-trait full animal model. Only the first three lactations are included in the analysis. The first lactation is divided into three stages namely, 100D, 200D, 300D each being considered as three separate traits. The resulting values from the three traits are combined into one to get the first lactation estimated breeding values (EBV. The genetic correlations between traits were all positive ranging from 0.78 to 0.94 between 100D and 303D of the lactation and between the 2nd and third lactation respectively. Estimates of heritabilities used in the analysis were 0.36, 0.39, 0.30, 0.32, and 0.33, for 100D, 200D, 300D, 2nd lactation and 3rd lactation respectively. The average EBVs of cows were plotted against birth year. The trend was positive with 4 kg and 8.4 kg increase per birth year for the 1st and both the 2nd and 3rd lactation respectively. This positive trend is consistent and may be responsible for the increase in milk production performance of cows. Apparently, selection of replacement animals based on milk production performance of dams and use of imported semen from proven bulls was effective before EBV information on sires and dams are available in the Philippines. The use of EBVs in selection would increase the rate of genetic improvement in dairy buffalo population in the Philippines.
Cross-bred dairy cows (n=202) were used to study the milk progesterone profiles 0, 5, 7, 12, 20, 28, 35 and 45 days after artificial insemination. It was found that 57% (115/202) of the cows had a normal oestrous cycle and conceived, but in 13% (15/115) of cows that conceived the embryos died between 28 and 35 days of gestation. A total of 43% (87/202) of the cows did not become pregnant and these could be classified into four groups: 15% (31/202) had normal oestrous cycles; 7% (15/202) were inseminated during the luteal phase, i.e. when progesterone concentrations were elevated; 14% (29/202) had irregular cycles; and 6% (12/202) were acyclic. In another study milk samples were collected every 3 days from 90 cross-bred dairy cows, commencing 15 days after parturition and continuing until each animal had been inseminated. The milk progesterone profiles of each cow were collated with the records of oestrus and insemination. The average post-partum anoestrous periods of primiparous and multiparous cows were 35.0 ± 16.4 and 34.9 ± 14.5 days, respectively. In 68% of the primiparous cows and 65% of the multiparous cows oestrus occurred between days 20 and 40 of the post-partum period. Sequential serum samples from 42 repeat breeder cows and 8 infertile heifers were analysed for progesterone, and their ovaries were examined weekly by rectal palpation. They were treated with either human chorionic gonadotrophin (HCG), pregnant mare serum gonadotrophin (PMSG) or prostaglandin F 2α . As a result, 23 cows and 5 heifers re-established oestrous cycles and became pregnant after AI. Progesterone profiles and rectal palpation revealed various causes of infertility, including ovarian cysts, irregular oestrous cycles, inactive ovaries and abnormal oviducts. Fifty-six per cent of repeat breeder cows and infertile heifers responded to hormone treatment in terms of resumed ovarian function. (author). 14 refs, 6 figs, 3 tabs
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.
McConnel, C; Lombard, J; Wagner, B; Kopral, C; Garry, F
Summary studies of dairy cow removal indicate increasing levels of mortality over the past several decades. This poses a serious problem for the US dairy industry. The objective of this project was to evaluate associations between facilities, herd management practices, disease occurrence and death rates on US dairy operations through an analysis of the National Animal Health Monitoring System's Dairy 2007 survey. The survey included farms in 17 states that represented 79.5% of US dairy operations and 82.5% of the US dairy cow population. During the first phase of the study operations were randomly selected from a sampling list maintained by the National Agricultural Statistics Service. Only farms that participated in phase I and had 30 or more dairy cows were eligible to participate in phase II. In total, 459 farms had complete data for all selected variables and were included in this analysis. Univariable associations between dairy cow mortality and 162 a priori identified operation-level management practices or characteristics were evaluated. Sixty of the 162 management factors explored in the univariate analysis met initial screening criteria and were further evaluated in a multivariable model exploring more complex relationships. The final weighted, negative binomial regression model included six variables. Based on the incidence rate ratio, this model predicted 32.0% less mortality for operations that vaccinated heifers for at least one of the following: bovine viral diarrhea, infectious bovine rhinotracheitis, parainfluenza 3, bovine respiratory syncytial virus, Haemophilus somnus, leptospirosis, Salmonella, Escherichia coli or clostridia. The final multivariable model also predicted a 27.0% increase in mortality for operations from which a bulk tank milk sample tested ELISA positive for bovine leukosis virus. Additionally, an 18.0% higher mortality was predicted for operations that used necropsies to determine the cause of death for some proportion of dead
Frequency of herd noncompliance for somatic cell count (SCC) based on current US and European Union (EU) standards as well as for standards proposed by the National Milk Producers Federation (NMPF) was examined for US Dairy Herd Improvement (DHI) herds. For current US standards, regulatory action is...
Izzo, M M; Humphris, M; Pryor, L; Perry, A; Morton, J M
To describe reproductive performance of lactating dairy cows after fixed-time artificial insemination (FTAI) with ovulation synchronisation and re-synchrony in Australian dairy herds, and to compare reproductive outcomes with those of conventional mating programs. The study was conducted in two seasonally calving dairy herds in which lactating dairy cows (n = 675) were enrolled into three treatment groups: group 1, oestrus detection and AI for 34 days followed by a natural service period; group 2, FTAI on day 1 followed by re-synchrony of all cows prior to ultrasound pregnancy diagnosis at day 31 and FTAI of cows diagnosed not pregnant at day 34, then a natural service period; group 3, FTAI on day 1 followed by oestrus detection and AI for 34 days, then a natural service period. First-service conception rate (FSCR), 6-week in-calf (6WIC) rate and proportions pregnant at the end of mating were compared using logistic regression with farm fitted as a fixed effect. Times from mating start date to conception were described using survival analysis with Kaplan-Meier failure functions. FSCRs (45.3%, 49.1% and 45.6% for groups 1, 2 and 3, respectively) and proportions pregnant at the end of mating (77.6%, 76.0% and 76.8% for groups 1, 2 and 3, respectively) were similar for all groups. The 6WIC rate in group 2 was similar to that in group 3 (70.4% vs. 67.2%; P = 0.486), but tended to be higher than in group 1 (70.4% vs. 62.0%, P = 0.066). The median days to pregnancy for cows that conceived was 1 day in groups 2 and 3 and 10 days in group 1. Mating plans that use FTAI with ovulation synchronisation and re-synchrony during the AI period can achieve comparable reproductive performance to conventional mating programs in seasonally calving dairy herds. © 2018 Australian Veterinary Association.
Thysen, Iver; Enevoldsen, Carsten
Two complementary approaches to produce visual information from reproduction records are described and exemplified. The Event Display shows all reproductive events, over a year, for all cows in a herd, by symbols placed in an array with columns representing calendar weeks and rows representing...... individual cows. The Reproduction Monitor consists of graphs of insemination and pregnancy rates evaluated weekly with a Bayesian technique. These visual monitoring tools are well suited to explore temporal variation in reproductive performance, they provide a quick overview of herd performance...
Thysen, Iver; Enevoldsen, Carsten
Two complementary approaches to produce visual information from reproduction records are described and exemplified. The Event Display shows all reproductive events, over a year, for all cows in a herd, by symbols placed in an array with columns representing calendar weeks and rows representing...... individual cows. The Reproduction Monitor consists of graphs of insemination and pregnancy rates evaluated weekly with a Bayesian technique. These visual monitoring tools are well suited to explore temporal variation in reproductive performance, they provide a quick overview of herd performance......, and they provide information about individual animals....
Vargas, B.; Herrero, M.; Arendonk, van J.A.M.
A dynamic performance model was integrated with a model that optimised culling and insemination policies in dairy herds using dynamic programming. The performance model estimated daily feed intake, milk yield and body weight change of dairy cows on the basis of availability and quality of feed and
In this thesis, the potential for improvements in surveillance of Mycobacterium avium subsp. paratuberculosis (Map) infection and paratuberculosis in dairy herds was investigated, leading to a reduction in surveillance costs whilst continuing to meet specific quality targets. In particular,
Kaniyamattam, Karun; Block, Jeremy; Hansen, Peter J; De Vries, Albert
The objective of this study was to find the optimal proportions of pregnancies from an in vitro-produced embryo transfer (IVP-ET) system and artificial insemination (AI) so that profitability is maximized over a range of prices for embryos and surplus dairy heifer calves. An existing stochastic, dynamic dairy model with genetic merits of 12 traits was adapted for scenarios where 0 to 100% of the eligible females in the herd were impregnated, in increments of 10%, using IVP-ET (ET0 to ET100, 11 scenarios). Oocytes were collected from the top donors selected for the trait lifetime net merit (NM$) and fertilized with sexed semen to produce IVP embryos. Due to their greater conception rates, first ranked were eligible heifer recipients based on lowest number of unsuccessful inseminations or embryo transfers, and then on age. Next, eligible cow recipients were ranked based on the greatest average estimated breeding values (EBV) of the traits cow conception rate and daughter pregnancy rate. Animals that were not recipients of IVP embryos received conventional semen through AI, except that the top 50% of heifers ranked for EBV of NM$ were inseminated with sexed semen for the first 2 AI. The economically optimal proportions of IVP-ET were determined using sensitivity analysis performed for 24 price sets involving 6 different selling prices of surplus dairy heifer calves at approximately 105 d of age and 4 different prices of IVP embryos. The model was run for 15 yr after the start of the IVP-ET program for each scenario. The mean ± standard error of true breeding values of NM$ of all cows in the herd in yr 15 was greater by $603 ± 2 per cow per year for ET100 when compared with ET0. The optimal proportion of IVP-ET ranged from ET100 (for surplus dairy heifer calves sold for ≥$300 along with an additional premium based on their EBV of NM$ and a ≤$100 embryo price) to as low as ET0 (surplus dairy heifer calves sold at $300 with a $200 embryo price). For the default
Moore, Dale A; Adaska, J M; Higginbotham, G E; Castillo, Alejandro R Dr.; Collar, Carol; Sischo, William M
Dairy producers seldom test or examine incoming cattle, although these important biosecurity practices are recommended. This pilot project examined risk management decisions that producers make when faced with test-positive animals in purchased groups of dairy cattle, in order to provide information on disease risks and conditions that could affect animal health and performance. New arrivals to seven herds at dairy farms in four California counties were examined and tested for a range of cond...
Hässig, M; Kemper-Gisler, D; Liesegang, A; Braun, U
The goal of this study was to compare production variables and veterinary costs between dairy herds enrolled in an integrated herd health program and herds with a conventional, non-computerized herd management. Four variables were used to assess the performance of the herds, including calving interval, milk production per lactation, as well as the product of calving interval x veterinary costs per year and the ratio of production to veterinary costs per year. A total of 22 dairy herds, serviced by the ambulatory clinic, University of Zurich, were investigated. There were 11 experimental herds that had been enrolled in an integrated herd health program, INTERHERD©, and 11 control herds. Data of the latter were derived from a computerized accounting system, OBLON DATA©. A total of 92'350 records from the years 1999 - 2005 were analyzed retrospectively. During the investigation period the calving interval did not significantly increase in experimental herds, whereas milk production steadily increased in both groups. The integrated herd health program did not result in additional costs when the dairy farms have no problems on a herd basis. From our study, differences in farms with and without herd health program are only marginal.
Haine, Denis; Delgado, Hector; Cue, Roger; Sewalem, Asheber; Wade, Kevin; Lacroix, René; Lefebvre, Daniel; Arsenault, Julie; Bouchard, Émile; Dubuc, Jocelyn
The relationship between cows' health, reproductive performance or disorders and their longevity is well demonstrated in the literature. However these associations at the cow level might not hold true at the herd level, and herd-level variables can modify cow-level outcomes independently of the cows' characteristics. The interaction between cow-level and herd-level variables is a relevant issue for understanding the culling of dairy cows. However it requires the appropriate group-level variables to assess any contextual effect. Based on 10 years of health and production data, the objectives of this paper are:(a) to quantify the culling rates of dairy herds in Québec; (b) to determine the profiles of the herds based on herd-level factors, such as demographics, reproduction, production and health indicators, and whether these profiles can be related to herd culling rates for use as potential contextual variables in multilevel modelling of culling risk. A retrospective longitudinal study was conducted on data from dairy herds in Québec, Canada, by extracting health information events from the dairy herd health management software used by most Québec producers and their veterinarians. Data were extracted for all lactations taking place between January 1st, 2001 and December 31st, 2010. A total of 432,733 lactations from 156,409 cows out of 763 herds were available for analysis. Thirty cow-level variables were aggregated for each herd and years of follow-up, and their relationship was investigated by Multiple Factor Analysis (MFA). The overall annual culling rate was 32%, with a 95% confidence interval (CI) of [31.6%,32.5%]. The dairy sale rate by 60 days in milk (DIM) was 3.2% [2.8%,3.6%]. The annual culling rate within 60 DIM was 8.2% [7.9%,8.4%]. The explained variance for each axis from the MFA was very low: 14.8% for the first axis and 13.1% for the second. From the MFA results, we conclude there is no relationship between the groups of herd-level indicators
Mejía, Miguel Eduardo; Lacau-Mengido, Isabel María
In Argentina, most dairy cows with endometritis are treated with prostaglandin (PGF(2alpha) or its analogs) and insemination is withheld until there are no signs of endometritis. The objective of the present study was to evaluate if this method of managing endometritis enhances reproductive performance. Three experiments were conducted over 4 years in a large farm in the west of Buenos Aires province. In Experiment 1, half of the cows diagnosed with endometritis (>1.5-fold difference in diameter of uterine horns, as determined by rectal palpation) received standard endometritis management (treatment with tiaprost, a PGF(2alpha) analog, rectal palpation every 20 days, and withholding of AI until endometritis apparently resolved) and the other half was untreated, with AI at the first estrus after the voluntary waiting period. Untreated cows were inseminated and conceived 20 days earlier than treated cows, and the pregnancy rate by Day 90 postpartum was higher in the untreated group. In Experiment 2, cows with endometritis were divided into four groups according to the severity of symptoms; within each group, cows were allocated to treatment or control, as in Experiment 1. Although first service conception rate decreased as endometritis severity increased, reproductive performance in treated versus control cows was similar to that of Experiment 1 (with no interaction due to degree of endometritis). Re-evaluation of the treated cow (to confirm uterine "normality") may have been responsible for the delay in conception in both experiments. The objective of Experiment 3 was to determine the effects of tiaprost treatment on clinically normal postpartum cows (no evidence of endometritis). Tiaprost treatment reduced the interval from calving to conception in multiparous cows, but it delayed conception and reduced the conception rate in primiparous cows. In conclusion, treatment with tiaprost impaired reproductive performance in primiparous cows (in the absence of
Nielsen, Søren Saxmose; Weber, M.F.; Kudahl, Anne Margrethe Braad
Stochastic simulation models are widely accepted as a means of assessing the impact of changes in daily management and the control of different diseases, such as paratuberculosis, in dairy herds. This paper summarises and discusses the assumptions of four stochastic simulation models and their use...... the models are somewhat different in their underlying principles and do put slightly different values on the different strategies, their overall findings are similar. Therefore, simulation models may be useful in planning paratuberculosis strategies in dairy herds, although as with all models caution...
Agerholm, J.S.; Willadsen, C. M.; Nielsen, Thomas Krogh
Diagnostic findings in 218 aborted bovine foetuses are reported. The materials were examined in a matched case-control study of 69 Danish dairy herds with a sudden increase in the number of abortions and a corresponding 69 control herds. Foetuses aborted during the subsequent 6-month period were...... examined to identify the cause of abortion if possible. A total of 186 specimens were submitted from case herds and 32 from control herds. A likely cause of abortion was diagnosed in 73 foetuses. The most common cause was bovine viral diarrhoea virus (BVDV: 13%) followed by Neospora caninum infection (10......%), mycosis (5%) and Bacillus licheniformis infection (4%). Foetal and/or placental lesions were found in a further 27 cases. Only BVDV infection and neosporosis were diagnosed in more than one foetus per herd and only protozoal associated abortions occurred significantly more frequently in the case, rather...
Brand, A.; Noordhuizen, J.P.T.M.; Schukken, Y.H.
This text aims to teach students, practitioners and farm advisors how to give management support to the dairy farmer in order to optimize the health, productivity and welfare of his herd. The book covers management practices and farm conditions which have both positive and negative influences on
Smith, Rebecca L.; Tauer, Loren W.; Schukken, Ynte H.; Lu, Zhao; Grohn, Yrjo T.
The objective of this study was to minimize the cost of controlling an isolated bovine tuberculosis (bTB) outbreak in a US dairy herd, using a stochastic simulation model of bTB with economic and biological layers. A model optimizer produced a control program that required 2-month testing intervals (TI) with 2 negative whole-herd tests to leave quarantine. This control program minimized both farm and government costs. In all cases, test-and-removal costs were lower than depopulation costs, although the variability in costs increased for farms with high holding costs or small herd sizes. Increasing herd size significantly increased costs for both the farm and the government, while increasing indemnity payments significantly decreased farm costs and increasing testing costs significantly increased government costs. Based on the results of this model, we recommend 2-month testing intervals for herds after an outbreak of bovine tuberculosis, with 2 negative whole herd tests being sufficient to lift quarantine. A prolonged test and cull program may cause a state to lose its bTB-free status during the testing period. When the cost of losing the bTB-free status is greater than $1.4 million then depopulation of farms could be preferred over a test and cull program. PMID:23953679
Ersbøll, Annette Kjær; Ersbøll, Bjarne Kjær; Houe, H.
According to the current literature BVDV-infected neighbours probably impose a high risk of infection of susceptible cattle herds. In the present study, the objective was to evaluate the risk of a dairy herd changing infection status (from not having persistently infected (PI) animals to having PI......). The neighbourhood was defined as the first order neighbouring cattle herds using a Delauney triangularization. In total, 13.3% of the dairy herds changed herd status to PI-herds during the study period that lasted from January 1, 1995, to June 30, 1996. The risk of becoming a PI-herd was negatively associated...... with the mean distance to the neighbouring herds (OR = 0.7 for an increase of 1 km). Presence of PI-herds in the neighbourhood increased the risk of becoming a PI-herd (OR = 1.37, 1.40, 1.70 for 1, 2, ≥3 PI-herds in the neighbourhood). Increasing herd size increased the risk of becoming a PI-herd (OR = 3...
Ćaǧlayan, Alper; Yüca, Songül
Herd management requires multidisciplinary practices including animal feeding, gynecology, artificial insemination, immunology, and similar topics. Animal feeding is the most delicate subject as the fodder expense is 70% of the farm cost and as nearly all of the metabolic diseases arising out as health problem are because of misfeeding. However, a business organization's being able to maintain making profit will be possible by taking a healthy calf from breeding herd every year. For this reason, precision registrations of birth and artificial insemination, following-up pregnant state of animals, and making the other animals pregnant as soon as possible should be primary aim. It should not be forgotten that diarrhea and pneumonia in calves are among the most frequently witnessed infection related health problems. Mastitis, metritis and foot diseases take an important place in mature cows. These diseases can be minimized by vaccinations that are done properly and in suitable time, in-service training of staffs, making shelters suitable for animals welfare, and improving the hygienic conditions.
Nilnont, Theerakul; Aiumlamai, Suneerat; Kanistanont, Kwankate; Inchaisri, Chaidate; Kampa, Jaruwan
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.
associated risk factors of bovine tuberculosis (BTB) among dairy cattle herds was ... Keywords: Bovine tuberculosis, Dairy cattle herd, Prevalence, Risk factor ..... Comparative Intradermal Tuberculin Test in Dairy Cattle in the North of Ecuador and Risk Factors Associated with Bovine. Tuberculosis. Am. J. Trop. Med. Hyg ...
Jones, P J; Sok, J; Tranter, R B; Blanco-Penedo, I; Fall, N; Fourichon, C; Hogeveen, H; Krieger, M C; Sundrum, A
Many believe the health status of organic dairy herds in Europe should be improved to meet consumers' and legislators' expectations to improve animal welfare. This paper reports on a study in four countries that examined dairy farmers' intentions towards improving the health status of their organic herds through the use of the Theory of Planned Behaviour. It was found that farmers across the countries were positive about taking additional preventative measures to improve the health status of their herds. They believed this would not only improve herd physical performance, such as milk yield and fertility, but also achieve greater cost effectiveness and improved job satisfaction for them. Most study farmers would implement a tailored package of improvement measures designed by the study team with higher uptake most likely being by younger farmers, those who make greater use of veterinarians and professional advisory services, and those supplying specialist milk-marketing chains. Furthermore, farmers will be most likely to take-up additional health promotion if compatible with their everyday activities and if they have strong business performance goals aimed at maximising the physical performance of the herd. Copyright © 2016 Elsevier B.V. All rights reserved.
Bebe, B.O.; Udo, H.M.J.; Jalvingh, A.W.
Insemination of cows after calving is often more prolonged than recommended by the extension service in the smallholder dairy herds. The rationale behind the practice is unknown. The objective of this study was to evaluate through simulation, the potential benefits of implementing early insemination of cows after calving as recommended by the extension. The simulation was based on a reference herd reflecting an average performing smallholder dairy herd in the Kiambu peri-urban area. Data inputs displaying collapsed lactation curve were obtained from the National Dairy Development Project reports. The study used a dynamic stochastic model designed for on-farm decision support in dairying which can be modified to farm specific situation. Simulations was performed till steady state was derived reflecting the reproductive and productivity which corresponds with the estimated input and output variable of the reference herd. This form the basic situation in which insemination is on 165 days after calving. This resulted in 465 days calving interval (CI), and on annual basis 2355 kg milk per cow, 2.7 calvings, 25.8% culling rates giving gross margins of Ksh. 14,933 per cow. Compare to the basic situation, inseminating cows on day 105 after calving (60 days earlier) improved the annual gross margins per cow by Ksh 1060. The improved gross margins resulted from Shortened CI by 41 days, increased annual calvings in the herd by 0.1, increased milk production by 74 kg per cow annually and reduce culling rate by 4.8% annually. The resultant effect of these did offset the increased costs of feeding which was Ksh 473 and 11 per cow annually for the concentrates and Napier, respectively. The results showed that early insemination has potential economic benefits to smallholders. Implementing early insemination decisions need consider the investment feeding. The study showed that it is difficult to get a replacement heifer at the present level of reproductive performance in
Enevoldsen, Carsten; Hindhede, Jens; Kristensen, T.
Variables related to health, reproduction, replacement milk production in 111 Danish dairy herds were studied with factor analysis. The objectives were to identify management types and to assess the relevance of those types for herd milk production. Median herd size and total milk production were...... for peak milk production, disease a complex pattern related to herd size and age, cow size live cattle sales. The potential for peak milk production, replacement intensity variability of milk production were strong predictors of herd milk production. Interactions with herd size were important. The derived...... factor scoring coefficients allowed assessment of the management type of a given herd....
Arede, Margarida; Nielsen, Per Kantsø; Ahmed, Syed Sayeem Uddin
Mycoplasma bovis is an important pathogen causing severe disease outbreaks in cattle farms. Since 2011, there has been an apparent increase in M. bovis outbreaks among Danish dairy cattle herds. The dairy cattle industry performed cross-sectional antibody screening for M. bovis on four occasions......, using the indirect BIO K 302 M. bovis enzyme-linked immunosorbent assay (ELISA) (Bio-X, Belgium) in bulk tank milk from all dairy herds between June 2013 and July 2014. The objective of this study was to investigate the evolution of the spatial distribution of M. bovis in the Danish dairy herd...... population throughout the study period. Repeated bulk tank milk samples were used as a proxy for the herd-level diagnosis. Descriptive and spatial analyses were performed for the four screening rounds. Based on a previous diagnostic test evaluation study, the M. bovis status for each herd was determined...
Subclinical mastitis had highest relative occurrence (88.1%). Prevalence of quarter SCM was over 40% in Urban (n=5402) and Peri-urban. Dairy (n=2454), and 25.1 % in Dairy Herds Intra-urban of the Secondary Towns. (n=2334) and the same increased with the herd size. On cow basis, prevalence of SCM was 18.7 % and ...
Berends, I.M.G.A.; Swart, W.A.J.M.; Frankena, K.; Muskens, J.; Lam, T.J.G.M.; Schaik, van G.
The aim of the study was to investigate the effect of BVDV-free certification of dairy herds on fertility and udder health. Cases were defined as dairy herds that had at least one BVDV-antigen positive animal, subsequently gained the BVDV-free status by participating in the BVDV-control programme of
Lissemore, Kerry D.
This review of the literature covers the changes in the approach to veterinary health management that led to the introduction of computerized herd health programs and the various other applications of the computer in the practice of dairy herd medicine. The role that production recording systems, mainframe computers, minicomputers, and microcomputers have played in the evolution of herd health programs are also reviewed.
Sidibe, M.; Boly, H.; Lakouetené, T.; Leroy, P.; Bosma, R.H.
Peri-urban dairy cattle farms within 50 km of Bobo-Dioulasso were studied to assess herd type, disease incidence, management, feeding and breeding strategy. Out of 417 cattle farmers, 42% had dairy objectives and were studied. Among these peri-urban dairy farmers, 60% were settled, 36% semi-settled,
Burow, E.; Rousing, T.; Thomsen, P. T.
Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been...... studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality (R......) inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than...
Dubuc, J; Buczinski, S
The objective of this study was to quantify the prevalence of hypoglycemia in hyperketonemic dairy cows during the early postpartum period. A prospective observational study was conducted in 100 dairy herds selected by convenience. Within all participating herds, 40 cows (or the entire herd if smaller than 40 cows) were enrolled in the study (total of 3,776 enrolled cows). Herds were visited every 2 wk by an animal health technician. Cows were bled from their coccygeal vessels once between 1 and 14 d in milk, and cow-side testing was performed for ketonemia and glycemia using a device validated in cattle (Precision Xtra, Abbott, Mississauga, ON, Canada). Hyperketonemia was defined as β-hydroxybutyrate ≥1.4 mmol/L, and hypoglycemia was defined as glucose ≤2.2 mmol/L. Descriptive statistics were computed at the cow and herd levels. The cow-level prevalence of hyperketonemia, hypoglycemia, and simultaneous hypoglycemia and hyperketonemia was 20.0% (757/3,776), 13.8% (642/3,776), and 6.2% (235/3,776), respectively. Within the subset of hyperketonemic cows only, the prevalence of hypoglycemia was 31.0% (235/757). At the herd level, the median prevalence was 17.5% (minimum: 5.0%, first quartile: 10.0%, third quartile: 22.5%, maximum: 77.5%) for hyperketonemia, 15.0% (minimum: 5.0%, first quartile: 12.5%, third quartile: 20.0%, maximum: 47.5%) for hypoglycemia, and 7.5% (minimum: 2.5%, first quartile: 5.0%, third quartile: 12.5%, maximum: 17.5%) for simultaneous hypoglycemia and hyperketonemia. The herd-level median prevalence of hypoglycemia within the subset of hyperketonemic cows only was 30.6% (minimum: 2.5%, first quartile: 20.0%, third quartile: 39.1%, maximum: 63.0%). The results from this study show that the prevalence of simultaneous hyperketonemia and hypoglycemia is relatively low in the overall early postpartum cow population but also that approximately one third of hyperketonemic cows are hypoglycemic, which might represent an opportunity to improve
Emanuelson, Ulf; Sjöström, Karin; Fall, Nils
Good animal health is a notion that is germane to organic dairy production, and it is expected that such herds would pay significant attention on the health of their animals. However, it is not known if the applied animal disease management is actually more adequate in organic dairy cattle herds than in conventional dairy herds. A questionnaire study on biosecurity and animal disease management activities was therefore conducted among Swedish farmers with organic and conventional dairy cattle herds. A total of 192 useable questionnaires were returned; response rates of 30.3 and 20.2% for organic and conventional farmers, respectively. Herd characteristics of the two herd types were very similar, except that pipeline/tie-stall systems were less common in organic farms and that organic farmers had a higher education level than their conventional counterparts. Also, very few systematic differences in general or specific disease management activities were observed between the two types of farms. The main exceptions being how milk from cows during antibiotic treatment was used, views on policy actions in relation to antibiotic use, and attitudes towards calling for veterinary support. Using milk from cows during antibiotic treatment was more common in conventional herds, although it was mainly given to bull calves. Farmers of organic herds were more positive to policy actions to reduce the use and need for antibiotics, and they reported waiting longer before contacting a veterinarian for calves with diarrhoea and cows with subclinical mastitis. The stated biosecurity and animal disease management was relatively equal in Swedish organic and conventional dairy herds. Our results thus indicate that animal health is as important in conventionally managed dairy herds in Sweden as in organically managed herds.
Full Text Available Abstract The decline in dairy herd fertility internationally has highlighted the limited impact of traditional veterinary approaches to bovine fertility management. Three questionnaire surveys were conducted at buiatrics conferences attended by veterinary practitioners on veterinary dairy herd fertility services (HFS in countries with a seasonal (Ireland, 47 respondents and non-seasonal breeding model (The Netherlands, 44 respondents and Portugal, 31 respondents. Of the 122 respondents, 73 (60% provided a HFS and 49 (40% did not. The majority (76% of all practitioners who responded stated that bovine fertility had declined in their practice clients' herds with inadequate cow management, inadequate nutrition and increased milk yield as the most important putative causes. The type of clients who adopted a herd fertility service were deemed more educated than average (70% of respondents, and/or had fertility problems (58% and/or large herds (53%. The main components of this service were routine postpartum examinations (95% of respondents, fertility records analysis (75% and ultrasound pregnancy examinations (69%. The number of planned visits per annum varied between an average of four in Ireland, where breeding is seasonal, and 23 in Portugal, where breeding is year-round. The benefits to both the practitioner and their clients from running a HFS were cited as better fertility, financial rewards and job satisfaction. For practitioners who did not run a HFS the main reasons given were no client demand (55% and lack of fertility records (33%. Better economic evidence to convince clients of the cost-benefit of such a service was seen as a major constraint to adoption of this service by 67% of practitioners.
Raboisson, D; Cahuzac, E; Sans, P; Allaire, G
Dairy cow mortality causes financial loss and is increasing over time; it indicates suboptimal herd health or welfare. To describe the herd-level and contextual factors affecting cow mortality, the French National Bovine Dataset Identification was used to create dairy, beef, or fattening units within farms, for 2005 and 2006. Mortality rate (MO-RA, outcome variable) and most variables were calculated at the unit level, whereas contextual variables were defined at the municipality level [cattle density, inhabitant density, agricultural land always with grass on overall agricultural land (ALWG/OAL)]. The localization (11 dairy production areas, representative of the farming systems) was also included. The statistical analysis was performed with a probit regression model (MO-RA=0 or>0) and with a linear model corrected by the Heckman method for bias sample selection. For 2005 and 2006, 3.8 and 3.7 million dairy cow-years, 101,445 and 96,954 dairy units, and 141,677 and 143,424 deaths were recorded, respectively. Over one-third of the units had no dairy cow mortality in 2005 or 2006. Overall MO-RA was 3.7 and 3.8% for 2005 and 2006, respectively. Restricted MO-RA (farms without death excluded) was 5.8% for 2005 and 2006. The correlation of MO-RA among units between the 2 yr was 0.25. The same effects and close estimate values were reported for 2005 and 2006 with both models. Mortality rate was positively associated with the number of cow-years, having a beef unit in addition to a dairy unit, the proportion of purchased cows, the proportion of first-calving cows, the average calving interval, being a Milk Control Program member, inhabitant density, not being in dairy production area Grand-Ouest, and ALWG/OAL. Negative associations were reported for breed other than Holstein, being a Good Breeding Practices member, having a calving peak in autumn, culling rate, and municipal cattle density. This study reports an average mortality rate for the French dairy cows. It
Waage, S.; Bjorland, J.; Caugant, D. A.
One hundred and seven bovine isolates of penicillin and tetracycline resistant Staphylococcus aureus, recovered from 25 different dairy herds in various parts of Norway, were characterized using antimicrobial susceptibility testing, multilocus enzyme electrophoresis, ribotyping, plasmid analysis...... different counties, were assigned to 6 different strains. Seven out of these 8 isolates had the same plasmid restriction profile. In conclusion, penicillin and tetracycline resistant S. aureus occurring in dairy herds in Norway mainly seems to represent one particular strain that has achieved widespread...
Enevoldsen, Carsten; Sørensen, J.T.
-life problems for the dairy farmer and the practicing veterinarian. The veterinarian was able to supply detailed information concerning managerial routines applied on the farm. Epidemiologic analyses of the collected data produced input for herd-specific modelling of herd dynamic and economic effects...
Kuipers, A.; Koops, W.J.; Wemmenhove, H.
The aim of this study was to examine the variation in antibiotic use and the effects of external factors on trends in antibiotic use at the herd level by using the number of daily dosages as an indicator for antibiotic use. For this purpose, antibiotic use was analyzed in 94 dairy herds in the
Full Text Available Abstract Background Mastitis is one of the major threats to animal health, in organic farming as well as conventional. Preliminary studies of organic dairy herds have indicated better udder health in such herds, as compared to conventional herds. The aim of this paper was to further study mastitis and management related factors in certified organic dairy herds. Methods An observational study of 26 certified organic dairy herds in mid-eastern Sweden was conducted during one year. A large-animal practitioner visited the herds three times and clinically examined and sampled cows, and collected information about general health and management routines. Data on milk production and disorders treated by a veterinarian in the 26 herds, as well as in 1102 conventional herds, were retrieved from official records. Multivariable logistic regression was used to assess associations between herd type (organic vs. conventional and incidence of disorders. Results The organic herds that took part in the study ranged in size from 12 to 64 cows, in milk production from 3772 to 10334 kg per cow and year, and in bulk milk somatic cell counts from 83000 to 280000 cells/ml. The organic herds were found to have a lower incidence of clinical mastitis, teat injuries, and a lower proportion of cows with a high somatic cell count (as indicated by the UDS, Udder Disease Score compared to conventional herds. The spectrum of udder pathogenic bacteria was similar to that found in other Swedish studies. Treatment of mastitis was found to be similar to what is practised in conventional herds. Homeopathic remedies were not widely used in the treatment of clinical mastitis. The calves in most of these organic herds suckled their dams for only a few days, which were not considered to substantially affect the udder health. The main management factor that was different from conventional herds was the feeding strategy, where organic herds used a larger share of forage. Conclusion Udder
Stengärde, L; Hultgren, J; Tråvén, M; Holtenius, K; Emanuelson, U
Risk factors associated with high or low long-term incidence of displaced abomasum (DA) or clinical ketosis were studied in 60 Swedish dairy herds, using multivariable logistic regression modelling. Forty high-incidence herds were included as cases and 20 low-incidence herds as controls. Incidence rates were calculated based on veterinary records of clinical diagnoses. During the 3-year period preceding the herd classification, herds with a high incidence had a disease incidence of DA or clinical ketosis above the 3rd quartile in a national database for disease recordings. Control herds had no cows with DA or clinical ketosis. All herds were visited during the housing period and herdsmen were interviewed about management routines, housing, feeding, milk yield, and herd health. Target groups were heifers in late gestation, dry cows, and cows in early lactation. Univariable logistic regression was used to screen for factors associated with being a high-incidence herd. A multivariable logistic regression model was built using stepwise regression. A higher maximum daily milk yield in multiparous cows and a large herd size (p=0.054 and p=0.066, respectively) tended to be associated with being a high-incidence herd. Not cleaning the heifer feeding platform daily increased the odds of having a high-incidence herd twelvefold (pketosis in Swedish dairy herds. These results confirm the importance of housing, management and feeding in the prevention of metabolic disorders in dairy cows around parturition and in early lactation. Copyright © 2011 Elsevier B.V. All rights reserved.
Enevoldsen, Carsten; Hindhede, Jens; Kristensen, T.
Variables related to health, reproduction, replacement milk production in 111 Danish dairy herds were studied with factor analysis. The objectives were to identify management types and to assess the relevance of those types for herd milk production. Median herd size and total milk production were...... 59 cows and 7100 kg of energy-corrected milk, respectively. Based on cow data, 22 herd variables were defined. A factor analysis identified 10 first-order factors and 5 second-order factors. The latter factors were valid indicators of replacement intensity, variability of milk production, potential...... for peak milk production, disease a complex pattern related to herd size and age, cow size live cattle sales. The potential for peak milk production, replacement intensity variability of milk production were strong predictors of herd milk production. Interactions with herd size were important. The derived...
Toni, F; Vincenti, L; Ricci, A; Schukken, Y H
The objective of this study was to describe the incidence and the impact of postpartum uterine diseases in postpartum cows on future uterine status and reproductive performance in large Italian dairy herds. This study provides an important quantitative estimate of uterine and postpartum diseases incidence that afflict high-producing Italian dairy cows. The total number of cows included in the study was 1498 on three farms; all cows were followed from the dry period until 300 days postpartum. All farms used high-quality data collection systems and standard operating procedures: weekly herd health visits, monthly Dairy Herd Improvement Association visits, and, due to cheese-making milk quality requirements, a supplementary milk sample collected at 7 ± 3 days postpartum evaluated for milk components. Clinical metritis in primiparous cows did not change the time to the first artificial insemination (AI) or days open; conversely, clinical metritis in multiparous cows had impact on the time to first AI (hazard ratio: 0.66, P conception rate at first insemination and a increase in days open (odds ratio: 0.64, P conception rate (odds ratio: 0.34, P conception rate both in the first-lactation and in older cows and had a strong negative effect on the proportion of pregnant cows at 300 days (P < 0.05). In conclusion, the impact of endometritis on fertility was true across lactation groups. A good management and precocious diagnosis of the pathologies is not resolutive to restore good fertility parameters, and understanding the immune response in first-lactation cows may be of value for developing alternative intervention protocols for older-lactation cows. Copyright © 2015 Elsevier Inc. All rights reserved.
Pinho, L; Thompson, G; Machado, M; Carvalheira, J
The objective of this study was to evaluate the effect of some management practices on the prevalence of Mycoplasma spp. in Northwestern Portuguese dairy farms from bulk tank milk (BTM) samples. Additionally, the within-herd prevalence of Mycoplasma spp. was also determined, but only in BTM positive herds. From May 2007 to November 2008, 492 BTM samples from 164 dairies randomly chosen in a population of 1234 dairy farms were analyzed. Five herds (3.0%) had positive mycoplasmal culture results, from which 4 out of 164 (2.4%) were Mycoplasma bovis, with simultaneous presence of Mycoplasma bovigenitalium or Mycoplasma canadense in two of those samples. In one out of 164 (0.6%) herds Mycoplasma capricolum subsp. capricolum was also found. In BTM positive Mycoplasma spp. herds, the apparent intra-herd prevalence was low and varied between 2.5% and 4.5%. Multiple locus variable-number of tandem-repeat analysis was conducted in order to compare the genetic relationship between the isolates. Mycoplasma spp. was found to be present in cows with subclinical mastitis with or without California Mastitis Test positive results, hence all cows should be tested when the agent is isolated from bulk tank rather than selecting suspected cows. A multivariable logistic regression using the Firth's penalized maximum likelihood estimation was performed showing that increasing number of lactating cows (OR=1.05; Pagent in mastitis control protocols in national dairies and in sanitary controls of transitioned animals between European countries. Copyright © 2012 Elsevier B.V. All rights reserved.
Berge, Anna C; Vertenten, Geert
The aim of this study was to determine the prevalence, major management systems, and fresh cow clinical conditions associated with ketosis in western European dairy herds. A total of 131 dairies were enrolled in Germany, France, Italy, the Netherlands, and the United Kingdom during 2011 to 2012. A milk-based test for ketones (Keto-Test; Sanwa Kagaku Kenkyusho Co. Ltd., Nagoya, Japan; distributed by Elanco Animal Health, Antwerp, Belgium) was used for screening cows between d 7 and 21 after calving and ketosis was defined as a Keto-Test ≥100µmol/L. Study cows were observed for clinical disease up to 35d postcalving. Multivariate analysis (generalized estimating equation logistic regression) was performed to determine country, farm, management, feed, and cow factors associated with ketosis and to determine associations between ketosis and fresh cow diseases. Thirty-nine percent of the cows were classified as having ketosis. The herd average of ketosis was 43% in Germany, 53% in France, 31% in Italy, 46% in the Netherlands, and 31% in the United Kingdom. Of the 131 farms, 112 (85%) had 25% or more of their fresh cows resulting as positive for ketosis. Clinical ketosis was not reported in most farms and the highest level of clinical ketosis reported was 23%. The risks of ketosis were significantly lower in Italy and the United Kingdom compared with France, the Netherlands, and Germany. Larger herd size was associated with a decreased risk of ketosis. The farms that fed partially mixed rations had 1.5 times higher odds of ketosis than those that fed total mixed rations. Cows that calved in April to June had the highest odds of ketosis, with about twice as high odds compared with cows that calved in July to September. The cows that calved in January to March tended to have 1.5 times higher risk of ketosis compared with cows that calved in July to September. The odds of ketosis in parity 2 and parity 3 to 7 was significantly higher (1.5 and 2.8 times higher
Diego B. Nóbrega
Full Text Available The objectives of this study were to isolate Klebsiella pneumoniae from different sources in three dairy cattle herds, to use the pulsed-field gel electrophoresis (PFGE to measure genotypic similarities between isolates within a dairy herd, to verify the production of extended-spectrum β-lactamases (ESBLs by the double-disk synergy test (DDST, and to use the PCR to detect the main ESBLs subgroups genes. Three dairy farms were selected based on previous mastitis outbreaks caused by K. pneumoniae. Milk samples were collected from lactating cows and from the bulk tank. Swabs were performed in different locations, including milking parlors, waiting room, soil, animal's hind limbs and rectum. K. pneumoniae was isolated from 27 cases of intramammary infections (IMI and from 41 swabs. For farm A isolates from IMI and bulk tank were considered of the same PGFE subtype. One isolate from a bulk tank, three from IMI cases and four from environmental samples were positive in the DDST test. All eight DDST positive isolates harbored the bla shv gene, one harbored the bla tem gene, and three harbored the bla ctx-m gene, including the bulk tank isolate. Our study confirms that ESBL producing bacteria is present in different locations in dairy farms, and may be responsible for IMI. The detection of ESBLs on dairy herds could be a major concern for both public and animal health.
Sorge, U S; Moon, R D; Stromberg, B E; Schroth, S L; Michels, L; Wolff, L J; Kelton, D F; Heins, B J
The objective of this study was to describe the prevalence and practices used to manage internal helminth parasites and external arthropod parasites on organic and conventional dairy herds in Minnesota. All organic (ORG) dairy herds in Minnesota (n=114) and a convenience sample of conventional herds were invited to participate in the study. Thirty-five ORG herds and 28 conventional herds were visited once in summer and fall of 2012. Conventional dairy herds were split into small conventional (SC,conventional herds (MC, ≥200 cows) so that SC herds were comparable in size to the ORG herds. Dairy managers were surveyed to assess their farm management practices and perceptions about parasites, hygiene scores were recorded for adult stock, and fecal samples were collected from a nominal 20 breeding-age heifers to characterize abundance of internal parasites. Nonparametric tests were used to compare fecal egg counts per gram (FEC) among farms grouped by management systems and practices. Organic farms had more designated pasture and were more likely to use rotational grazing compared with conventional farms, but the stocking densities of animals on pasture were similar among farm types. The overall FEC were very low, and only a few individual ORG heifers had FEC >500 eggs/gram. Samples from heifers on ORG farms had significantly more strongyle-type eggs than those on SC and MC farms (ORG: 6.6±2.1; SC: 0.5±0.3; MC: 0.8±0.7), but egg counts of other types of gastrointestinal parasites did not differ significantly among the 3 herd groups. Fly control measures were applied mainly to milking cows and preweaned calves and were used on 88.6% of ORG herds, 60.0% of SC herds, and 91.7% of MC herds. Approximately half of the producers reported having seen skin conditions suggestive of lice or tail mange in their cattle during the previous winter (ORG: 48.6%, SC: 57.1%, MC: 53.9%). Although most conventional producers reported treating these skin conditions, most organic
An outbreak of Salmonella Kentucky followed by a high level of sustained endemic prevalence was recently observed in a US adult dairy herd enrolled in a longitudinal study involving intensive fecal sampling. To understand the invasion ability and transmission dynamics of Salmonella Kentucky in dairy...
Jones, P.J.; Sok, J.; Tranter, R.B.; Blanco-Penedo, I.; Fall, N.; Fourichon, C.; Hogeveen, H.; Krieger, M.C.; Sundrum, A.
Many believe the health status of organic dairy herds in Europe should be improved to meet consumers’ and legislators’ expectations to improve animal welfare. This paper reports on a study in four countries that examined dairy farmers’ intentions towards improving the health status of their
Recently the number of milking cows has increased substantially in the Dar es Salaam region due to an increasing demand for fresh milk in this densely populated urban centre. It is estimated that there are 1,765 smallholder dairy herds with 8,233 improved dairy animals in and around the Dar es
Shahid, M Q; Reneau, J K; Chester-Jones, H; Chebel, R C; Endres, M I
The objectives of this study were to describe on-farm mortality and to investigate cow- and herd-level risk factors associated with on-farm mortality in Midwest US dairy herds using lactation survival analysis. We analyzed a total of approximately 5.9 million DHIA lactation records from 10 Midwest US states from January 2006 to December 2010. The cow-level independent variables used in the models were first test-day milk yield, milk fat percent, milk protein percent, fat-to-protein ratio, milk urea nitrogen, somatic cell score, previous dry period, previous calving interval, stillbirth, calf sex, twinning, calving difficulty, season of calving, parity, and breed. The herd-level variables included herd size, calving interval, somatic cell score, 305-d mature-equivalent milk yield, and herd stillbirth percentage. Descriptive analysis showed that overall cow-level mortality rate was 6.4 per 100 cow-years and it increased from 5.9 in 2006 to 6.8 in 2010. Mortality was the primary reason of leaving the herd (19.4% of total culls) followed by reproduction (14.6%), injuries and other (14.0%), low production (12.3%), and mastitis (10.5%). Risk factor analysis showed that increased hazard for mortality was associated with higher fat-to-protein ratio (>1.6 vs. 1 to 1.6), higher milk fat percent, lower milk protein percent, cows with male calves, cows carrying multiple calves, higher milk urea nitrogen, increasing parity, longer previous calving interval, higher first test-day somatic cell score, increased calving difficulty score, and breed (Holstein vs. others). Decreased hazard for mortality was associated with higher first test-day milk yield, higher milk protein, and shorter dry period. For herd-level factors, increased hazard for mortality was associated with increased herd size, increased percentage of stillbirths, higher somatic cell score, and increased herd calving interval. Cows in herds with higher milk yield had lower mortality hazard. Results of the study
Andersen, H. J.; Pedersen, L. H.; Aarestrup, Frank Møller
The aim of this study was to evaluate the Danish surveillance program of Streptococcus agalactiae in dairy herds with respect to 1) fluctuation over time of the presence of S. agalactiae in bulk tank milk, 2) sensitivity and specificity of the bacteriological method used, and 3) contamination...... of bulk tank milk samples with milk from other herds. From June to September 1996, bulk tank milk was sampled from 100 Danish dairy herds seven times, with intervals of 2 wk. The samples were examined for the presence of S. agalactiae by four different methods: 1) by the method approved for the program, 2...... the isolates. Streptococcus agalactiae was found in eight of 96 herds in which S. agalactiae had never previously been found during the surveillance program. Streptococcus agalactiae was not found in all seven sampling rounds in any of the eight herds. Comparing the approved method with supplemental findings...
Nielsen, Liza Rosenbaum; Nielsen, Søren Saxmose
The aim of this study was to describe a structured approach to effectively reduce Salmonella Dublin prevalence in infected dairy herds based on a step-wise procedure. Furthermore, the aim was to describe tools for management and monitoring, and to report on development in prevalence among young...... stock and adult cattle in 10 case herds that were followed for more than three years. The five steps in the structured approach were: 1) risk scoring to determine transmission routes within the herd and into the herd; 2) determining a plan of action; 3) performing management changes to close important...
Full Text Available Abstract Background Bovine respiratory syncytial virus (BRSV and bovine corona virus (BCV affects cattle worldwide. Our objective was to evaluate the effects of these infections on general health and reproduction parameters measurable on herd level and to explore the association between antibody status and some herd characteristics. Methods We collected a pooled milk sample from five primiparous cows from 79 Swedish dairy herds in September 2006. The samples were analysed for immunoglobulin G antibodies to BCV and BRSV with indirect enzyme-linked immunosorbent assays. Herd level data from 1 September 2005 to 30 August 2006 were accessed retrospectively. The location of the herds was mapped using a geographical information system. Results Ten herds were antibody negative to both viruses and were compared with 69 herds positive to BCV or BRSV or both. Positive herds had a higher (P = 0.001 bulk tank milk somatic cell count (BMSCC compared with negative herds. The medians for all other analyzed health and reproductive parameters were consistently in favour of the herds negative to both viruses although the differences were not statistically significant. A higher proportion (P = 0.01 of herds used professional technicians for artificial insemination, rather than farm personnel, amongst the 33 herds negative to BCV compared with the 46 positive herds. Conclusions Our result shows that herds that were antibody positive to BCV and/or BRSV had a higher BMSCC compared with herds negative to BCV and BRSV. There was also tendency that negative herds had a better general herd health compared with positive. A higher proportion amongst the BCV negative herds used external technicians for AI instead of farm personnel, indicating that it is possible to avoid infection although having regular visits. Negative herds were located in close proximity to positive herds, indicating that local spread and airborne transmission between herds might not be of great
Full Text Available The prevalence of bovine viral diarrhoea (BVD serologically positive animals in 18 dairy herds with clinical and pathological lesions suggestive of BVD infection, the post-vaccinal seroconversion rates in negative animals vaccinated twice with an inactivated BVD vaccine, and the control measures taken, are described. The pathological and histopathological findings in 6 necropsies performed on animals that died in 5 separate herds closely resembled published descriptions. Positive immunohistochemistry results in 3 cases confirmed the diagnosis in those animals. In 1 herd the prevalence of prevaccinal BVDantibodies was only 36.8 %, while the prevalence varied from 79.85 to 100 % in the remainder. Control measures taken included immunoprophylaxis with an inactivated vaccine, culling animals that were serologically negative after vaccination that were regarded as probably persistently infected (PI and the implementation of additional biosecurity measures. The prevalence of serologically negative PI animals in 10 herds varied from 0.38 to 4.04 %, with 8 herds less than 1 %and 2 herds at 2.79 %and 4.04 %, respectively. Methods based on vaccinating the herd, followed by serological testing and culling cattle that did not develop an antibody titre, are not reliable. The identification of PI animals should be confirmed by isolation of the virus or identification of the antigen.
Arede, Margarida; Nielsen, Per Kantsø; Ahmed, Syed Sayeem Uddin
, using the indirect BIO K 302 M. bovis enzyme-linked immunosorbent assay (ELISA) (Bio-X, Belgium) in bulk tank milk from all dairy herds between June 2013 and July 2014. The objective of this study was to investigate the evolution of the spatial distribution of M. bovis in the Danish dairy herd...... population throughout the study period. Repeated bulk tank milk samples were used as a proxy for the herd-level diagnosis. Descriptive and spatial analyses were performed for the four screening rounds. Based on a previous diagnostic test evaluation study, the M. bovis status for each herd was determined...... in space. The global clustering analysis showed that M. bovis test-positive herds were spatially correlated in rounds one, three and four. These findings were supported to some extent by the local clustering analysis, which found significant high- and low-risk spatial clusters in rounds one and three...
Full Text Available A longitudinal study was performed in a Swedish dairy herd where Neospora caninum had been isolated from a stillborn calf. Starting in autumn 1994, blood samples from all female animals in the herd were collected once yearly until 1999. The sera were analysed for presence of IgG1 antibodies to N. caninum by the iscom ELISA, and by an avidity ELISA to establish the timing of infection. In addition, data on reproductive performance were compiled. During the study the percentage of seropositive female animals increased from 63% to 87%. In 1994 a large number of young animals tested seropositive although their dams were seronegative, indicating that a transmission of the parasite other than the vertical had recently occurred. Low avidity values supported this assumption. The annual abortion rate increased from a mean of 2% before the initiation of the study to 9% in 1994–1998. During the same time, as judged by the avidity data, a large proportion of the animals shifted from being recently to being chronically infected. The source of the external infection in the herd could not be identified.
ESTRATEGIC MANAGEMENT DURING THE TRANSICION PERIOD TO OPTIMISE PRODUCTIVITY AND REPRODUCTIVE PERFORMANCE IN THE DAIRY HERD MANEJO ESTRATÉGICO DURANTE EL PERIODO DE TRANSICIÓN PARA OPTIMIZAR LA PRODUCCIÓN Y EL COMPORTAMIENTO REPRODUCTIVO GANADO LECHERO
Full Text Available In dairy herds, the interval between calving and pregnancy depend on many factors including preparation of the cow for calving, dietary management before and after calving. Factors such as hypocalcemia and body condition are determinant in the presentation of postpartum pathologies and ovarian activity resumption. Additionally, management of the dairy cattle should include fixed time artificial insemination protocols to increase the number of animals bred close to the voluntary waiting period and pregnancy rates. The following review will address topics related with cattle body condition and puerperal hypocalcemia that affect negatively postpartum reproductive performance and also will, address management alternatives to improve pregnancy rates y to reduce days open.Los días abiertos en el hato lechero dependen de muchos factores, dentro de los cuales se debe considerar, la preparación de la vaca preparto incluyendo el manejo dietario pre y postparto. Factores como la hipocalcemia y la condición corporal son determinantes en la presentación de patologías puerperales y en el inicio de la ciclicidad. Adicional a este manejo, se debe considerar la utilización de protocolos de inseminación a tiempo fijo que incrementa el número de animales servidos cerca del tiempo voluntario de espera y genera un incremento en las tasas de preñez. La presente revisión discutirá temas relacionados con la condición corporal y la presentación de hipocalcemia puerperal que afectan la fertilidad posparto de la vaca, así como alternativas para mejorar las tasa de preñez y reducir los días abiertos.
Gädicke, P; Vidal, R; Monti, G
Bovine abortion is a limiting factor for dairy business, as it decreases milk production and the potential, number of herd replacements, increases feeding and medical treatment costs, increases the number of artificial inseminations to obtain a calf as well as culling rates of cows. An estimation of the economic impact of abortion in dairy farms in Chile is not available yet. The aim of this study was to estimate the economic consequences of bovine abortion syndrome (BAS) in dairy cows from Chile. A stochastic model was proposed to evaluate the cost of an abortion on a yearly basis to include variability in cost and income by dairy and by year. The marginal total net revenue (ΔTNR) for a typical, lactation was obtained by the calculating the difference between total revenues (retail milk and calf sales) and total expenses (production cost (cows, feeding, labor, health) plus administrative and, general costs) for lactation with and without abortion. Production data were obtained from a retrospective study of 127 dairy herds located in southern Chile between 2000 and 2006. Milk production from cows with and without abortion was estimated by a mixed model using milk test day data. Production cost and prices paid to farmers were obtained from service company records (TODOAGRO S.A.). Cost and income value was corrected for inflation and expressed in the values from 2006. In addition, a separate analysis for different parities (1, 2, 3 or more) was performed. Distributions for the stochastic variables were obtained by fitting distributions from our database using @Risk. The stochastic variables included in the analysis were all related to income, feeding, depreciation, health, Artificial Insemination and general costs like fuel, salaries, taxes, etc. There was a high probability (89.20%) of a negative ΔTNR in lactations with abortion for overall, parities, with a mean loss of $ -143.32. Stratifying by parity, the predicted mean of the distribution for ΔTNR in each
Bihrmann, Kristine; Nielsen, Søren Saxmose; Toft, Nils
Paratuberculosis is a chronic infection of economic importance to the cattle industry and a voluntary control programme is offered to Danish dairy farmers. Our objective was to evaluate spatial differences in both control programme participation and paratuberculosis prevalence in Denmark. The study...... included 4414 dairy herds: 1249 were participating in the control programme, and 1503 were tested for antibodies to Mycobacterium avium subsp. paratuberculosis (MAP). Spatial differences were evaluated by kernel smoothing, kriging, and cluster analysis. Participation was lowest among herds on the island...... Zealand (≤23%). The risk of a herd being infected with MAP was found to be high on most of Zealand, but the uncertainty of this result was large due to a limited number of tested herds. In the rest of the country, the south western part of the peninsula Jutland had the highest risk of MAP (≥91%). The risk...
Gohary, Khaled; Overton, Michael W; Von Massow, Michael; LeBlanc, Stephen J; Lissemore, Kerry D; Duffield, Todd F
The objective of this study was to develop a model to estimate the cost of a case of subclinical ketosis (SCK) in Canadian dairy herds. Costs were derived from the default inputs, and included increased clinical disease incidence attributable to SCK, $76; longer time to pregnancy, $57; culling and death in early lactation attributable to SCK, $26; milk production loss, $44. Given these figures, the cost of 1 case of SCK was estimated to be $203. Sensitivity analysis showed that the estimated cost of a case of SCK was most sensitive to the herd-level incidence of SCK and the cost of 1 day open. In conclusion, SCK negatively impacts dairy herds and losses are dependent on the herd-level incidence and factors included in the calculation.
Wall, E; Coffey, M P; Pollott, G E
Many governments have signed up to greenhouse gas emission (GHGE) reduction programmes under their national climate change obligations. Recently, it has been suggested that the use of extended lactations in dairy herds could result in reduced GHGE. Dairy GHGE were modelled on a national basis and the model was used to compare emissions from lactations of three different lengths (305, 370 and 440 days), and a current 'base' scenario on the basis of maintaining current milk production levels. In addition to comparing GHGE from the average 'National Herd' under these scenarios, results were used to investigate how accounting for lactations of different lengths might alter the estimation of emissions calculated from the National Inventory methodology currently recommended by Intergovernmental Panel on Climate Change. Data for the three lactation length scenarios were derived from nationally recorded dairy performance information and used in the GHGE model. Long lactations required fewer milking cows and replacements to maintain current milk yield levels than short ones, but GHGEs were found to rise from 1214 t of CO2 equivalent (CE)/farm per year for lactations of 305 days to 1371 t CE/farm per year for 440-day lactations. This apparent anomaly can be explained by the less efficient milk production (kg milk produced per kg cow weight) found in later lactation, a more pronounced effect in longer lactations. The sensitivity of the model to changes in replacement rate, persistency and level of milk yield was investigated. Changes in the replacement rate from 25% to 20% and in persistency by −10% to +20% resulted in very small changes in GHGE. Differences in GHGE due to the level of milk yield were much more dramatic with animals in the top 10% for yield, producing about 25% less GHGE/year than the average animal. National Inventory results were investigated using a more realistic spread of lactation lengths than recommended for such calculations using emissions
Nielsen, S.S.; Weber, M.F.; Kudahl, Anne Margrethe Braad
in the design of certification, surveillance, and control strategies for paratuberculosis in cattle herds. A detailed comparison is made between the Dutch JohneSSim and the Danish PTB-Simherd, using the same context of a set of control strategies in a typical Dutch/Danish herd. The conclusion is that while...
Engelen, E. van; Schotten, N.; Schimmer, B.; Hautvast, J.L.; Schaik, G. van; Duijnhoven, Y.T. van
Despite cattle herds can harbor Coxiella burnetii, risk factors for C. burnetii presence in dairy cattle herds are largely unknown. Therefore, C. burnetii herd prevalence and risk factors for bulk tank milk (BTM) positivity were investigated. In this cross-sectional study, a questionnaire was filled
Burow, E; Rousing, T; Thomsen, P T; Otten, N D; Sørensen, J T
Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality® inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than during full-time winter housing. Furthermore, we expected improved welfare with an increase in daily summer grazing hours. In total, 41 herds have been visited once in the winter and once in the summer of 2010 to assess their welfare status with 17 different animal- and resource-based welfare measures. A panel of 20 experts on cattle welfare and husbandry evaluated the relative weight of the 17 welfare measures in a multidimensional assessment scheme. They estimated exact weights for a priori constituted severe compared with moderate scores of welfare impairment concerning each measure, as well as relevance of the measures in relation to each other. A welfare index (WI; possible range 0 to 5400) was calculated for each herd and season with a higher index indicating poorer welfare. The within-herd comparison of summer grazing v. winter housing considered all the 17 measures. The mean WI in summer was significantly lower (better) than in winter (mean 2926 v. 3330; paired t-test P = 0.0001) based on a better state of the integument, claw conformation and better access to water and
van den Borne, Bart H P; Graber, Hans U; Voelk, Verena; Sartori, Carlotta; Steiner, Adrian; Haerdi-Landerer, M Christina; Bodmer, Michèle
Staphylococcus aureus is a common mastitis causing pathogen of dairy cattle. Several S. aureus genotypes exist, of which genotype B (GTB) is highly prevalent in Swiss dairy herds. Dairy farming in mountainous regions of Switzerland is characterised by the movement of dairy cattle to communal pasture-based operations at higher altitudes. Cows from different herds of origin share pastures and milking equipment for a period of 2 to 3 months during summer. The aim of this longitudinal observational study was to quantify transmission of S. aureus GTB in communal dairy operations. Cows (n=551) belonging to 7 communal operations were sampled at the beginning and end of the communal period. Transmission parameter β was estimated using a Susceptible-Infectious-Susceptible (SIS) model. The basic reproduction ratio R 0 was subsequently derived using previously published information about the duration of infection. Mean transmission parameter β was estimated to be 0.0232 (95% CI: 0.0197-0.0274). R 0 was 2.6 (95% CI: 2.2-3.0), indicating that S. aureus GTB is capable of causing major outbreaks in Swiss communal dairy operations. This study emphasized the contagious behaviour of S. aureus GTB. Mastitis management in communal dairy operations should be optimized to reduce S. aureus GTB transmission between cows and back to their herds of origin. Copyright © 2016 Elsevier B.V. All rights reserved.
Gates, M C; Woolhouse, M E J; Gunn, G J; Humphry, R W
The success of bovine viral diarrhoea virus (BVDV) eradication campaigns can be undermined by spread through local transmission pathways and poor farmer compliance with biosecurity recommendations. This work combines recent survey data with cattle movement data to explore the issues likely to impact on the success of BVDV control in Scotland. In this analysis, data from 249 beef suckler herds and 185 dairy herds in Scotland were studied retrospectively to determine the relative influence of cattle movements, local spread, and biosecurity on BVDV seropositivity. Multivariable logistic regression models revealed that cattle movement risk factors had approximately 3 times greater explanatory power than risk factors for local spread amongst beef suckler herds, but approximately the same explanatory power as risk factors for local spread amongst dairy herds. These findings are most likely related to differences in cattle husbandry practices and suggest that where financial prioritization is required, focusing on reducing movement-based risk is likely to be of greatest benefit when applied to beef suckler herds. The reported use of biosecurity measures such as purchasing cattle from BVDV accredited herds only, performing diagnostic screening at the time of sale, implementing isolation periods for purchased cattle, and installing double fencing on shared field boundaries had minimal impact on the risk of beef or dairy herds being seropositive for BVDV. Only 28% of beef farmers and 24% of dairy farmers with seropositive herds recognized that their cattle were affected by BVDV and those that did perceive a problem were no less likely to sell animals as replacement breeding stock and no more likely to implement biosecurity measures against local spread than farmers with no perceived problems. In relation to the current legislative framework for BVDV control in Scotland, these findings emphasize the importance of requiring infected herds take appropriate biosecurity measures
Demeter, R M; Kristensen, A R; Dijkstra, J; Oude Lansink, A G J M; Meuwissen, M P M; van Arendonk, J A M
Herd optimization models that determine economically optimal insemination and replacement decisions are valuable research tools to study various aspects of farming systems. The aim of this study was to develop a herd optimization and simulation model for dairy cattle. The model determines economically optimal insemination and replacement decisions for individual cows and simulates whole-herd results that follow from optimal decisions. The optimization problem was formulated as a multi-level hierarchic Markov process, and a state space model with Bayesian updating was applied to model variation in milk yield. Methodological developments were incorporated in 2 main aspects. First, we introduced an additional level to the model hierarchy to obtain a more tractable and efficient structure. Second, we included a recently developed cattle feed intake model. In addition to methodological developments, new parameters were used in the state space model and other biological functions. Results were generated for Dutch farming conditions, and outcomes were in line with actual herd performance in the Netherlands. Optimal culling decisions were sensitive to variation in milk yield but insensitive to energy requirements for maintenance and feed intake capacity. We anticipate that the model will be applied in research and extension. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Malher, Xavier; Bareille, Nathalie; Noordhuizen, Jos P T M; Seegers, Henri
A case-based learning (CBL) format was implemented at the Veterinary School of Nantes, France, for veterinary students in their last year of the curriculum who had chosen to track toward a farm animal career. The focus of the CBL format was learning about dairy herd health consultancy. The goal was to emphasize teamwork among students, introduce professional communications and advisory relationships with clients, and work within the technical and economic limitations of participating farms. These farms volunteered to participate and had identified a problem. The learning objectives included gaining basic knowledge of herd-level diseases and the methods to control these within herds. The program focused on health audits of dairy farms performed by teams of four to five students, culminating in submission of a herd health management action plan specific for the farm visited by each team. The CBL program was comprised of defined learning objectives for each team. The learning process was supervised, from orientation through to validation, by a panel of experts from within the veterinary school and from local industry. Teams submitted written reports that listed recommendations and an action plan for implementation. This report was defended by each team in front of the farmers, their professional partners, and the panel of supervisors. Assessment of the program by students, participating farms, and industry professionals was positive.
Antimicrobial resistance in bacterial pathogens is an increasing public health concern. The objective of this study was to examine antimicrobial resistance in Salmonella and E. coli isolates from Pennsylvania dairy herds. Manure composite samples were collected from 76 farms: on each farm one sample...
Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be the primary source of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-se...
A review of existing literature was conducted to determine the prevalence of purulent vaginal discharge (PVD) in dairy herds around the world and detection methodologies that influence prevalence estimates. Four databases (PubMed, Google Scholar, Web of Science, and Scopus) were queried with the sea...
Jensen, Anette Møllegaard; Bjorkman, C.; Kjeldsen, A.M.
The prevalence and distribution of seropositivity towards the protozoan parasite Neospora caninum were studied in single blood samples from 1561 cows from 31 Danish dairy herds. Blood samples were analysed by an indirect enzyme-linked immunoassay and an indirect fluorescent-antibody test, Seropre...
Thomsen, Peter; Sørensen, Jan Tind; Ersbøll, Annette Kjær
was to evaluate 3 commercial hoof-care products in 12 Danish dairy herds (testing each product in 4 herds) using a controlled clinical trial. One-half of the herds were conventional and the other half was organically managed. The hoof-care products represented the 3 main groups of active compounds currently legal......Digital dermatitis is a serious problem in dairy production in many countries. Footbaths have been used extensively for the prevention and cure of digital dermatitis. But there is a lack of scientific evidence regarding the effectiveness of hoof-care products used in footbaths. The objective...... new infections). Percentage cured ranged from 13.6 to 100, and percentage new infections ranged from 0 to 35.5. For all hoof-care products, the difference between treatment and control sides was not statistically significant. Overall, there was no effect on percentage cured or percentage new...
Mastitis is one of the most important diseases in dairy cattle. Recently, the so-called minor pathogens, of which coagulase-negative staphylococci (CNS) are the most important group of bacteria, has received more attention. This thesis focuses on the role of CNS in udder health of dairy cows. The
Oliveira, Victor H S; Sørensen, Jan T; Thomsen, Peter T
The relationship between biosecurity and digital dermatitis (DD) was evaluated in 8,269 cows from a convenience sample of 39 freestall dairy herds. The hypothesis was that poor implementation of biosecurity was associated with higher within-herd prevalence of DD. All lactating cows were scored as negative or positive for DD at the hind legs during milking in the milking parlor. Information about biosecurity was obtained through questionnaires addressed to farmers, on-farm observations, and information from the Danish Cattle Database (www.seges.dk). These assessment tools covered potential infection sources of DD pathogens to susceptible cows (e.g., via animals, humans, manure, vehicles, equipment, and facilities). External and internal biosecurity measures were explanatory variables in 2 separate logistic regression models, whereas within-herd DD prevalence was the outcome. Overall DD prevalence among cows and herds were 24 and 97%, respectively; the within-herd DD prevalence ranged from 0 to 56%. Poor external biosecurity measures associated with higher prevalence of DD were recent animal purchase, access to pasture, lack of boots available for visitors, farm staff working at other dairy farms as well, hoof trimming without a professional attending, and animal transporters having access to cattle area. For internal biosecurity, higher DD prevalence were associated with infrequent hoof bathing, manure scraping less than 8 times a day, manure removal direction from cows to heifers, animal pens' exit without water hoses, manure-handling vehicle used in other activities, and water troughs contaminated with manure. These findings showed that improvements on biosecurity may be beneficial for controlling DD in dairy herds. The study is relevant for farmers facing problems with DD, as well as hoof trimmers, advisors, and veterinarians, who can use the results for optimized recommendations regarding biosecurity in relation to DD. Furthermore, our results might be
Agerholm, J.S.; Willadsen, C. M.; Nielsen, Thomas Krogh
%), mycosis (5%) and Bacillus licheniformis infection (4%). Foetal and/or placental lesions were found in a further 27 cases. Only BVDV infection and neosporosis were diagnosed in more than one foetus per herd and only protozoal associated abortions occurred significantly more frequently in the case, rather...
Full Text Available Abstract Background Several management and environmental factors are known as contributory causes of clinical mastitis in dairy herd. The study objectives were to describe the structure of herd-specific mastitis management and environmental factors and to assess the relevance of these herd-specific indicators to mastitis incidence rate. Methods Disease reports from the Danish Cattle Data Base and a management questionnaire from 2,146 herds in three Danish regions were analyzed to identify and characterize risk factors of clinical mastitis. A total of 94 (18 continuous and 76 discrete management and production variables were screened in separate bivariate regression models. Variables associated with mastitis incidence rate at a p-value Results Three latent factors (quality of labor, region of Denmark and claw trimming, and quality of outdoor holding area were identified from 14 variables. Daily milk production per cow, claw disease, quality of labor and region of Denmark were found to be significantly associated with mastitis incidence rate. A common multiple regression analysis with backward and forward selection procedures indicated there were 9 herd-specific risk factors. Conclusion Though risk factors ascertained by farmer-completed surveys explained a small percentage of the among-herd variability in crude herd-specific mastitis rates, the study suggested that farmer attitudes toward mastitis and lameness treatment were important determinants for mastitis incidence rate. Our factor analysis identified one significant latent factor, which was related to labor quality on the farm.
Doherty Michael L
Full Text Available Abstract Background Infection with bovine herpesvirus-1 (BHV-1 causes a wide range of disease manifestations, including respiratory disease and abortion, with world-wide distribution. The primary objective of the present study was to describe aspects of BHV-1 infection and control on Irish farms, including herd-level seroprevalence (based on pooled sera and vaccine usage. Methods The characteristics of a diagnostic indirect BHV-1 antibody ELISA test when used on serum pools were evaluated using laboratory replicates for use in the seroprevalence study. The output from this indirect ELISA was expressed as a percentage positivity (PP value. A proposed cut off (PCO PP was applied in a cross-sectional study of a stratified random sample of 1,175 Irish dairy and beef cattle herds in 2009, using serum pools, to estimate herd seroprevalence. The study was observational, based primarily on the analysis of existing samples, and only aggregated results were reported. For these reasons, ethical approval was not required. Bulk milk samples from a subset of 111 dairy herds were analysed using the same ELISA. Information regarding vaccine usage was determined in a telephone survey. Results A PCO PP of 7.88% was determined to give 97.1% sensitivity and 100% specificity relative to the use of the ELISA on individual sera giving maximization of the prevalence independent Youden's index, on receiver operating characteristics analysis of replicate results. The herd-level BHV-1 seroprevalence was 74.9% (95% CI - 69.9%-79.8%, with no significant difference between dairy and beef herds. 95.5% agreement in herd classification was found between bulk milk and serum pools. Only 1.8 percent of farmers used BHV-1 marker vaccine, 80% of which was live while 75% of vaccinated herds were dairy. A significant association was found between herd size (quartiles and seroprevalence (quartiles. Conclusions The results from this study indicate BHV-1 infection is endemic, although
Voelk, V; Graber, H U; van den Borne, B H P; Sartori, C; Steiner, A; Bodmer, M; Haerdi-Landerer, M C
Staphylococcus aureus is a major mastitis-causing pathogen. Various genotypes have been recently identified in Switzerland but Staph. aureus genotype B (GTB) was the only genotype associated with high within-herd prevalence. The risk of introducing this Staph. aureus genotype into a herd may be increased by frequent animal movements. This may also be the case when cows from different herds of origin are commingled and share their milking equipment for a limited period of time. The aim of the present study was to determine the prevalence of Staph. aureus GTB in seasonally communal dairy herds before and after a summer period when dairy farming is characterized by mixing cows from different herds of origin in 1 communal operation. In addition, the environment was investigated to identify potential Staph. aureus GTB reservoirs relevant for transmission of the disease. A total of 829 cows from 110 herds of origin in 9 communal operations were included in the study. Composite milk samples were collected from all cows during the first or second milking after arrival at the communal operation and again shortly before the end of the season. Swab samples from the environment, involved personnel, and herding dogs present were collected before the cows arrived. At the end of the season, sampling of personnel was repeated. All samples were analyzed for the presence of Staph. aureus GTB using an established quantitative PCR. At the beginning of the season, Staph. aureus GTB-positive cows were identified in 7 out of 9 communal operations and the within-communal operation prevalence ranged from 2.2 to 38.9%. At the second sampling, all communal operations were Staph. aureus GTB positive, showing within-communal operation prevalence from 1 to 72.1%. The between-herd of origin prevalence increased from 27.3 to 56.6% and the cow-level prevalence increased from 11.2% at the beginning of the season to 29.6% at the end of the season. On 3 different communal operations, Staph. aureus
Weber Nielsen, M S; Domecq, J J; Davis, L E; Beede, D K; Budine, M; Martsolf, F
The Dairy Challenge contest allows undergraduate students to apply knowledge gained in the classroom in an evaluation of the management practices of commercial dairy farms. University faculty partnered with industry representatives to develop the competition. Participants in the Dairy Challenge do the following: 1) critically evaluate dairy herd management practices and make recommendations for improvements; 2) visit local dairy farms and gain knowledge of different farms' management practices; 3) meet and interact with potential employers from the dairy industry during the contest; 4) evaluate herd records and utilize knowledge of dairy herd management software and computer presentation tools; 5) test their speaking, presentation, and problem-solving skills; and 6) work as a team to build consensus and tag-team speaking formats. Teams of four undergraduate students critically evaluate a commercial dairy farm using herd records, a description of farm operations, and tour of the farm facilities. The farmer answers questions pertaining to management of the farm in a group interview with all teams and in a separate interview with each individual team. Teams give a 20-min presentation that is scored on the description and assessment of the management practices and recommendations for improvements in management and facilities. Additionally, scoring is based on apparent level of preparation, speaking, presentation skills, and responses to judges' questions. The judges are university specialists and dairy industry professionals. This capstone experience allows students to interact with dairy farmers and representatives from the dairy industry and expands their knowledge and skills gained during their academic career.
Raaperi, K; Bougeard, S; Aleksejev, A; Orro, T; Viltrop, A
The associations between herd bovine herpesvirus 1 (BHV-1) seroprevalence, along with other infectious and farm management factors with bovine respiratory disease (BRD) in dairy calves and heifers, were investigated. Serum samples from 103 dairy cattle herds were analyzed for antibodies against BHV-1, bovine respiratory syncytial virus (BRSV), bovine viral diarrhea virus (BVDV), and Mycoplasma bovis (M. bovis). A questionnaire was used to record herd management practices. A high occurrence of respiratory disease in unweaned calves was associated with low to moderate and high prevalence of BHV-1 among cows (OR=14.8, p=0.005 and OR=19.2, p=0.002, respectively) and positive BVDV status of a herd (OR=5.1, p=0.02). The presence of BVDV in a herd was related to a high incidence of respiratory disease in heifers 3-16 months old (OR=4.3, p=0.027). Based on the results of multiple correspondence analysis, holding youngstock separately from cows until pregnancy, introducing new animals and the activities of on-farm employees may contribute to a higher incidence of BRD. Copyright © 2011 Elsevier Ltd. All rights reserved.
Full Text Available In November 2008, a total of 19,910 bulk tank milk (BTM samples were obtained from dairy farms from all over Germany, corresponding to about 20% of all German dairy herds, and analysed for antibodies against the bovine lungworm Dictyocaulus viviparus by use of the recombinant MSP-ELISA. A total number of 3,397 (17.1%; n = 19,910 BTM samples tested seropositive. The prevalences in individual German federal states varied between 0.0% and 31.2% positive herds. A geospatial map was drawn to show the distribution of seropositive and seronegative herds per postal code area. ELISA results were further analysed for associations with land-use and climate data. Bivariate statistical analysis was used to identify potential spatial risk factors for dictyocaulosis. Statistically significant positive associations were found between lungworm seropositive herds and the proportion of water bodies and grassed area per postal code area. Variables that showed a statistically significant association with a positive BTM test were included in a logistic regression model, which was further refined by controlled stepwise selection of variables. The low Pseudo R(2 values (0.08 for the full model and 0.06 for the final model and further evaluation of the model by ROC analysis indicate that additional, unrecorded factors (e.g. management factors or random effects may substantially contribute to lungworm infections in dairy cows. Veterinarians should include lungworms in the differential diagnosis of respiratory disease in dairy cattle, particularly those at pasture. Monitoring of herds through BTM screening for antibodies can help farmers and veterinarians plan and implement appropriate control measures.
Oliveira, Victor Henrique Silva de; Sørensen, Jan Tind; Thomsen, Peter T.
as negative or positive for DD at the hind legs during milking in the milking parlor. Information about biosecurity was obtained through questionnaires addressed to farmers, on-farm observations, and information from the Danish Cattle Database (www.seges.dk). These assessment tools covered potential infection...... among cows and herds were 24 and 97%, respectively; the within-herd DD prevalence ranged from 0 to 56%. Poor external biosecurity measures associated with higher prevalence of DD were recent animal purchase, access to pasture, lack of boots available for visitors, farm staff working at other dairy farms...
Nielsen, Lennarth Ravn; Warnick, L. D.; Greiner, M.
A surveillance program in which all cattle herds in Denmark are classified into Salmonella infection categories has been in place since 2002. Dairy herds were considered test negative and thus most likely free of infection if Salmonella antibody measurements were consistently low in bulk tank milk...... between 2 consecutive quarters of the year. The Salmonella serotypes in question were Salmonella Dublin or other serotypes that cross-react with the Salmonella Dublin antigen in the ELISA (e.g., some Salmonella Typhimurium types). Two logistic regression models that accounted for repeated measurements...
Enevoldsen, Carsten; Sørensen, J.T.
Collaboration with practicing veterinarians was established in a research project and has resulted in several epidemiologic tools to assist them in their work. Simultaneously, the research group obtained continuous access to valid and precise data and obtained first-hand knowledge about real......-life problems for the dairy farmer and the practicing veterinarian. The veterinarian was able to supply detailed information concerning managerial routines applied on the farm. Epidemiologic analyses of the collected data produced input for herd-specific modelling of herd dynamic and economic effects...
Stengärde, Lena; Holtenius, Kjell; Emanuelson, Ulf; Hultgren, Jan; Niskanen, Rauni; Tråvén, Madeleine
Sixty dairy herds were studied to investigate the association between long-term incidence of displaced abomasum and clinical ketosis and body condition score and blood profiles, including parameters estimating energy metabolism and hepatic lipidosis in the periparturient period and early lactation. Blood samples were taken around parturition and in early lactation from cows without apparent clinical symptoms of metabolic disorders. A difference in metabolism between high and low incidence herds was shown post-partum by a lower metabolic index (the revised Quantitative Insulin Sensitivity Check Index, RQUICKI), and tendencies for higher concentrations of glucose, insulin and non-esterified fatty acids in the high incidence herds. High incidence herds had more cows and produced on average 1400kg energy-corrected milk per cow per year more than the low incidence herds. No differences were found in parameters reflecting liver cell damage. In the first 3weeks post-partum the RQUICKI was a more sensitive marker of herds with a high incidence of displaced abomasum and clinical ketosis than any of the individual parameters, but further research is needed before practical applications of the RQUICKI can be foreseen. Copyright © 2010 Elsevier Ltd. All rights reserved.
Bontje, D.M.; Backer, J.A.; Hogerwerf, L.; Roest, H.I.J.; Roermund, van H.J.W.
Between 2006 and 2009 the largest human Q fever epidemic ever described occurred in the Netherlands. The source of infection was traced back to dairy goat herds with abortion problems due to Q fever. The first aim of control measures taken in these herds was the reduction of human exposure. To
Demeter, R.M.; Kristensen, A.R.; Dijkstra, J.; Oude Lansink, A.G.J.M.; Meuwissen, M.P.M.; Arendonk, van J.A.M.
Herd optimization models that determine economically optimal insemination and replacement decisions are valuable research tools to study various aspects of farming systems. The aim of this study was to develop a herd optimization and simulation model for dairy cattle. The model determines
This thesis comprises studies on surveillance of Bovine Viral Diarrhea (BVD) in Danish dairy herds. BVD is caused by a Pestivirus of the Flaviviridae family (BVDV) that can infect domestic and wild ruminants (e.g. deer). The main sources of infection are the persistently infected animals (PI) which...... and income of farmers. In Denmark, the BVD eradication program started in 1994. During the last twenty years, while the BVD herd incidence decreased to only sporadic cases, the average herd size has increased. Currently (2014), BVD is considered eradicated from Denmark. In this situation, newly infected...... of BVDV introduction. The main source of infection was represented by the import of live cattle from countries where BVD is endemic. With the current situation, the overall median risk was estimated to one BVDV introduction per 9 years (5th percentile = 59; 95th percentile = 3). By introducing simple...
Kirkeby, Carsten Thure; Gussmann, Maya Katrin; Græsbøll, Kaare
are Staphylococcus aureus, Streptococcus agalactiae and Streptococcus uberis. The contagious transmission is simulating transmission, e.g. via milk liners, and depends on the number of quarters with contagious pathogens in the herd. We chose to focus on these four pathogens because they are common in Danish dairy...... is often caused by more than one pathogen in the same herd, such a simulation model should also be pathogen-specific to account for different transmission characteristics and treatment effects. Moreover, as different strains of pathogens can have different transmission routes (i.e. environmental...... implemented two different transmission modes, namely environmental transmission based on a continuous reservoir of pathogens in the farm, and contagious IMI originating from other infected animals in the herd. Currently, the environmental pathogen included is Escherichia coli, and the contagious pathogens...
Agger, Jens Frederik; Paul, Suman; Christoffersen, Anna-Bodil
The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bulk tank milk (BTM) samples from 100 randomly selected Danish dairy cattle herds. Antibody levels were measured by an enzyme-linked immuno-sorbent assay. Before testing the herds, the farm managers were...... interviewed about hired labour, biosecurity, housing and herd health during the 12 months prior to the study. Variables considered important for C. burnetii antibody positivity in multivariable logistic regression analysis included the sharing of machines between farms (OR = 3.6), human contacts (OR = 4...... of calving and disease pens also showed significant association in univariable analysis. This study demonstrates that strict biosecurity is important for the prevention of infections with C. burnetii....
M. M. Hossain
Full Text Available Aim: The present study was conducted to find out the causes and factors affecting the dairy cattle mortality. Materials and Methods: A retrospective study of dairy cattle mortality on the Central Cattle Breeding and Dairy Farm (CCBDF in Bangladesh was carried out between 1992 and 2007. Sixteen years of data on mortality of dairy cattle were analyzed for the effects of year, season, age, sex, breed, and etiology on mortality rate. Results: The average overall mortality rate was 5.60% and on average, female cattle (55.71% were found to die more than males (44.29%. Mortality was more in crossbred cattle than in indigenous breed. Higher mortality of cattle was observed in rainy season (37.98% followed by winter (33.03% and summer (28.99%. The major causes of death were diseases of the respiratory tract, mainly pneumonia (39.91%. Tuberculosis was the second most common cause of mortality accounting for 20.58% of deaths. The other major cause of death was disease of the alimentary tract, mainly enteritis (15.58%. Other causes of death occurred in the following frequencies: malnutrition (5.91%, debility (4.43%, hairball (3.35%, tympanitis (2.56%, babesiosis (2.27%, internal haemorrhage (2.16%, black quarter (1.76%, and foot and mouth disease (1.48%. Conclusions: Of the four potential risk factors investigated, age was the most important factor and significantly associated with mortality. During the first month of life, calves had a higher risk of mortality than adults.
Full Text Available Fasciolosis is generally a subclinical infection of dairy cows and can cause marked economic losses. This study investigated the prevalence and spatial distribution of fasciolosis in dairy cow herds in Ireland using an in-house antibodydetection enzyme-linked immunosorbent assay applied to bulk tank milk (BTM samples collected during the autumn of 2012. A total of 5,116 BTM samples were collected from 4,602 different herds, with 514 farmers submitting BTM samples in two consecutive months. Analysis of the BTM samples showed that 82% (n = 3,764 of the dairy herds had been exposed to Fasciola hepatica. A total of 108 variables, including averaged climatic data for the period 1981-2010 and contemporary meteorological data for the year 2012, such as soil, subsoil, land cover and habitat maps, were investigated for a possible role as predictor of fasciolosis. Using mainly climatic variables as the major predictors, a model of the predicted risk of fasciolosis was created by Random Forest modelling that had 95% sensitivity and 100% specificity. The most important predictors in descending order of importance were: average of annual total number of rain-days for the period 1981-2010, total rainfall during September, winter and autumn of 2012, average of annual total number of wet-days for the period 1981- 2010 and annual mean temperature of 2012. The findings of this study confirm the high prevalence of fasciolosis in Irish dairy herds and suggest that specific weather and environmental risk factors support a robust and precise distribution model.
Hermans, K; Waegeman, W; Opsomer, G; Van Ranst, B; De Koster, J; Van Eetvelde, M; Hostens, M
Scientific journals and popular press magazines are littered with articles in which the authors use data from dairy herd management software. Almost none of such papers include data cleaning and data quality assessment in their study design despite this being a very critical step during data mining. This paper presents 2 novel data cleaning methods that permit identification of animals with good and bad data quality. The first method is a deterministic or rule-based data cleaning method. Reproduction and mutation or life-changing events such as birth and death were converted to a symbolic (alphabetical letter) representation and split into triplets (3-letter code). The triplets were manually labeled as physiologically correct, suspicious, or impossible. The deterministic data cleaning method was applied to assess the quality of data stored in dairy herd management from 26 farms enrolled in the herd health management program from the Faculty of Veterinary Medicine Ghent University, Belgium. In total, 150,443 triplets were created, 65.4% were labeled as correct, 17.4% as suspicious, and 17.2% as impossible. The second method, a probabilistic method, uses a machine learning algorithm (random forests) to predict the correctness of fertility and mutation events in an early stage of data cleaning. The prediction accuracy of the random forests algorithm was compared with a classical linear statistical method (penalized logistic regression), outperforming the latter substantially, with a superior receiver operating characteristic curve and a higher accuracy (89 vs. 72%). From those results, we conclude that the triplet method can be used to assess the quality of reproduction data stored in dairy herd management software and that a machine learning technique such as random forests is capable of predicting the correctness of fertility data. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
ÖZSOY, Serhat; ALTUNATMAZ, Kemal
This study was carried out to determine the relationship between aflatoxins taken with feed, laminitis, lameness and impaired fertility. Lesions were identified in the claw and hock region, causing lameness in 45 cattle in an establishment of 300 Holstein dairy cattle. Of these lame cattle, 27 had cystic ovaries and 10 had cystic ovaries together with clinical metritis. The increase in lameness and fertility problems occurring in this herd, living under the same management and feeding conditi...
Howell, Alison; Baylis, Matthew; Smith, Rob; Pinchbeck, Gina; Williams, Diana
The liver fluke Fasciola hepatica is a trematode parasite with a worldwide distribution and is the cause of important production losses in the dairy industry. The aim of this observational study was to assess the prevalence of exposure to F. hepatica in a group of high yielding dairy herds, to determine the risk factors and investigate their associations with production and fertility parameters. Bulk milk tank samples from 606 herds that supply a single retailer with liquid milk were tested with an antibody ELISA for F. hepatica. Multivariable linear regression was used to investigate the effect of farm management and environmental risk factors on F. hepatica exposure. Higher rainfall, grazing boggy pasture, presence of beef cattle on farm, access to a stream or pond and smaller herd size were associated with an increased risk of exposure. Univariable regression was used to look for associations between fluke exposure and production-related variables including milk yield, composition, somatic cell count and calving index. Although causation cannot be assumed, a significant (phepatica exposure and estimated milk yield at the herd level, representing a 15% decrease in yield for an increase in F. hepatica exposure from the 25th to the 75th percentile. This remained significant when fertility, farm management and environmental factors were controlled for. No associations were found between F. hepatica exposure and any of the other production, disease or fertility variables. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.
Marcus Rebouças Santos
Full Text Available Bovine herpesvirus 1 (BoHV-1 causes major losses in worldwide livestock, affecting the respiratory and reproductive tracts of bovine. In the past decades, the number of cases in Brazil has been gradually increasing. Therefore, it is important to assess the distribution of infection in different regions of the country. In the state of Espírito Santo (ES the BoHV 1 infection rate in dairy cattle herds is unknown. Thus, the aim of this study was to detect neutralizing antibodies against BoHV-1 in serum samples from 1,161 non-vaccinated cows from 59 dairy cattle herds in 23 municipalities of the Metropolitan, North, Northwest and South macro-regions. The identification of seropositive cows was evaluated by the virus neutralization test. The results showed that of all serum samples evaluated 775 (66.75% had neutralizing antibodies against BoHV-1. Moreover, all herds were found positive; however, the percentage of positive cows varied among regions; 49.06%, 62.15%, 67.21% and 80.04% for the Metropolitan, South, North and Northwest macro-regions, respectively. In this study, the results clearly indicate the dissemination of the viral agent in dairy cattle in the ES state, requiring the monitoring and control of diseases related to BoHV-1 infection.
Dolecheck, K A; Silvia, W J; Heersche, G; Wood, C L; McQuerry, K J; Bewley, J M
The objective of this study was to compare the reproductive performance of cows inseminated based on automated activity monitoring with hormone intervention (AAM) to cows from the same herds inseminated using only an intensive timed artificial insemination (TAI) program. Cows (n=523) from 3 commercial dairy herds participated in this study. To be considered eligible for participation, cows must have been classified with a body condition score of at least 2.50, but no more than 3.50, passed a reproductive tract examination, and experienced no incidences of clinical, recorded metabolic diseases in the current lactation. Within each herd, cows were balanced for parity and predicted milk yield, then randomly assigned to 1 of 2 treatments: TAI or AAM. Cows assigned to the TAI group were subjected to an ovulation synchronization protocol consisting of presynchronization, Ovsynch, and Resynch for up to 3 inseminations. Cows assigned to the AAM treatment were fitted with a leg-mounted accelerometer (AfiAct Pedometer Plus, Afimilk, Kibbutz Afikim, Israel) at least 10 d before the end of the herd voluntary waiting period (VWP). Cows in the AAM treatment were inseminated at times indicated by the automated alert system for up to 90 d after the VWP. If an open cow experienced no AAM alert for a 39±7-d period (beginning at the end of the VWP), hormone intervention in the form of a single injection of either PGF2α or GnRH (no TAI) was permitted as directed by the herd veterinarian. Subsequent to hormone intervention, cows were inseminated when alerted in estrus by the AAM system. Pregnancy was diagnosed by ultrasound 33 to 46 d after insemination. Pregnancy loss was determined via a second ultrasound after 60 d pregnant. Timed artificial insemination cows experienced a median 11.0 d shorter time to first service. Automated activity-monitored cows experienced a median 17.5-d shorter service interval. No treatment difference in probability of pregnancy to first AI, probability
The Environmental Monitoring and Support Laboratory-Las Vegas, U.S. Environmental Protection Agency, maintains an experimental dairy herd and farm facility in Area 15 of the Nevada Test Site for the U.S. Energy Research and Development Administration. This status report covers the period from January 1, 1976, through December 31, 1976. Improvements, changes, and additions made to the facilities, production and reproduction statistics for individual cows and the herd, the veterinary medicine practices employed, and summaries of the metabolism studies that involved the dairy herd are covered in this report
Full Text Available During the periparturient period, subclinical hypocalcemia (total plasma Ca concentration <2.0 mmol/l is a potential problem for the dairy cow; consequently, its prevention is essential for success of fertility and productive performance. Dietary cation–anion difference (DCAD has been defined as the difference in milliequivalents of cations (Na, K and anions (Cl, S per kilogram of dry matter (DM and has a direct impact on blood acid–base metabolism. Diets rich in K and Na induce metabolic alkalosis, interfering with tissue sensitivity to parathyroid hormone, and diets rich in Cl and S (anionic salts cause metabolic acidosis, reducing the risk of hypocalcemia. Consequently, the use of anionic salts has become a popular method to prevent hypocalcemia in dairy cattle. Monitoring diets with anionic salts can be done by measuring urine pH, with optimal values between 6.2 and 6.8 for Holstein cows. The objective of this report is to present a herd case investigation involving a dairy farm feeding a very low DCAD (−143 mEq/kg DM, expecting improved Ca homeostasis. The diet of −143 mEq/kg (urine pH 5.2–5.8 was changed to a diet with −53 mEq/kg DM (urine pH 6.2–6.8. Blood samples were taken at the time of calving for 10 cows that calved before and then for 10 cows that calved after changing the diet. Cows with extremely low DCAD had Ca concentrations of 2.11 ± 0.22 mmol/l and cows with a more moderated DCAD, 2.11 ± 0.16 mmol/l (P > 0.05. Several other blood metabolites (P, Mg, Na, K, Cl, albumin, globulins, blood urea nitrogen, creatinine, and GGT were also similar between groups. This very low DCAD during the prepartum period may severely compromise animal physiology unnecessarily, with little advantage over normal calcium concentrations at parturition, when compared with a less negative DCAD (−53 mEq/kg DM. Feeding a less negative DCAD ration (−53 mEq/kg DM did not decrease plasma Ca levels right after
Full Text Available Shortening or omitting the dry period of dairy cows improves metabolic health in early lactation and reduces management transitions for dairy cows. The success of implementation of these strategies depends on their impact on milk yield and farm profitability. Insight in these impacts is valuable for informed decision-making by farmers. The aim of this study was to investigate how shortening or omitting the dry period of dairy cows affects production and cash flows at the herd level, and greenhouse gas emissions per unit of milk, using a dynamic stochastic simulation model. The effects of dry period length on milk yield and calving interval assumed in this model were derived from actual performance of commercial dairy cows over multiple lactations. The model simulated lactations, and calving and culling events of individual cows for herds of 100 cows. Herds were simulated for 5 years with a dry period of 56 (conventional, 28 or 0 days (n = 50 herds each. Partial cash flows were computed from revenues from sold milk, calves, and culled cows, and costs from feed and rearing youngstock. Greenhouse gas emissions were computed using a life cycle approach. A dry period of 28 days reduced milk production of the herd by 3.0% in years 2 through 5, compared with a dry period of 56 days. A dry period of 0 days reduced milk production by 3.5% in years 3 through 5, after a dip in milk production of 6.9% in year 2. On average, dry periods of 28 and 0 days reduced partial cash flows by €1,249 and €1,632 per herd per year, and increased greenhouse gas emissions by 0.7% and 0.5%, respectively. Considering the potential for enhancing cow welfare, these negative impacts of shortening or omitting the dry period seem justifiable, and they might even be offset by improved health.
Full Text Available The aim of this study was to retrospectively analyse the results of milk samples obtained from South African dairy herds during the period 1996 to April 2007 in order to identify possible trends in isolates of microorganisms and their pathogenicity under field conditions. Milk samples were obtained from 7 of the 9 provinces in South Africa where there are low numbers of dairy cows. Although there is scientific limitation to a country wide survey, such as the variation in herd size, management skills, parity, milk yield, milking frequency and other parameters, the size of this database helps to give a fair indication of general udder health in South Africa. Cytology and routine bacteriology were performed on 379 000 milk samples of lactating cows and bacteriology on 11 946 samples from non-lactating cows. According to the results obtained, mastitis did not decrease in South Africa over the test period. The prevalence of mastitis and teat canal infection was lowest in 2002. Mastitis and teat canal infection increased from 2002 to 2006 from 8.1 % and 24.1 % to 15.4 and 30.0 % respectively. The percentage of mastitogenic pathogens isolated from cows over these years also varied. Previously unknown or almost eradicated mastitogenic pathogens such as αβ haemolytic Staphylococcus aureus which is thought to be of human origin, Streptococcus agalactiae and Enterococcus canis were responsible for numerous mastitis outbreaks seen in the test samples. Coagulase-negative staphylococci were the most frequently isolated bacteria in milk samples from both lactating and dry cows, followed by Staphylococcus aureus and Streptococcus agalactiae. Although Staphylococcus aureus remained the principal mastitogenic pathogen in South Africa, owing to its chronic nature and resultant economic losses, most cases of mastitis were caused by coagulase-negative staphylococci. This finding increases the importance of coagulase-negative staphylococci (formerly described as a
Torsein, Maria; Lindberg, Ann; Svensson, Catarina; Jensen, Sören Krogh; Berg, Charlotte; Waller, Karin Persson
A study of herd-level risk factors for calf mortality in large Swedish dairy herds showed low serum concentrations of α-tocopherol and β-carotene in 1-7 day old calves to be more common in high mortality herds. Therefore, we aimed to investigate if calf mortality risk at herd level is associated with concentrations of α-tocopherol and/or β-carotene at individual level in feed, colostrum, cow and calf serum, while controlling for herd level covariates. Inclusion criteria were affiliation to the Swedish official milk recording scheme, herd size of ≥ 120 milking cows/year, calf mortality risk (day 1-90) of at least 6% (high mortality; HM) or less than 1% (low mortality; LM) and located within one of two regions in southern Sweden. This cross-sectional study was performed in 2010 in 19 (n HM = 9; n LM = 10) dairy herds. Questionnaires were used to collect information about feed and routines for colostrum feeding. Feed (n = 57), colostrum (n = 162), cow serum (n = 189) and calf serum samples (n = 187) were collected and analysed for α-tocopherol and β-carotene. Other analyses e.g. total serum protein, fat content, and total solids in colostrum were also performed. Linear regression models with vitamin concentrations in feed, colostrum, cow and calf serum as outcome were performed. Calves in HM herds had lower concentrations of α-tocopherol in serum than calves in LM herds, but the effect depended on total protein status in serum of the calf (P = 0.036). Calves from herds that fed transition milk for 3 days or more had higher α-tocopherol concentrations in serum than calves from herds feeding transition milk up to 2 days (P = 0.013). Fat percentage in colostrum was positively associated with α-tocopherol (P mortality risks were associated with lower concentrations of α-tocopherol in calf serum for calves with failure of passive transfer. Feeding transition milk longer was associated with higher concentrations of α-tocopherol in calf
Full Text Available Abstract Hazard Analysis and Critical Control Points (HACCP systems are a risk based preventive approach developed to increase levels of food safety assurance. This is part 1 of a pilot study on the development, implementation and evaluation of a HACCP-based approach for the control of good udder health in dairy cows. The paper describes the use of a novel approach based on a deconstruction of the infectious process in mastitis to identify Critical Control Points (CCPs and develop a HACCP-based system to prevent and control mastitis in dairy herds. The approach involved the creation of an Infectious Process Flow Diagram, which was then cross-referenced to two production process flow diagrams of the milking process and cow management cycle. The HACCP plan developed, may be suitable for customisation and implementation on dairy farms. This is a logical, systematic approach to the development of a mastitis control programme that could be used as a template for the development of control programmes for other infectious diseases in the dairy herd.
Beekhuis-Gibbon, Lies; Whyte, Paul; O'Grady, Luke; More, Simon J; Doherty, Michael L
Hazard Analysis and Critical Control Points (HACCP) systems are a risk based preventive approach developed to increase levels of food safety assurance. This is part 1 of a pilot study on the development, implementation and evaluation of a HACCP-based approach for the control of good udder health in dairy cows. The paper describes the use of a novel approach based on a deconstruction of the infectious process in mastitis to identify Critical Control Points (CCPs) and develop a HACCP-based system to prevent and control mastitis in dairy herds. The approach involved the creation of an Infectious Process Flow Diagram, which was then cross-referenced to two production process flow diagrams of the milking process and cow management cycle. The HACCP plan developed, may be suitable for customisation and implementation on dairy farms. This is a logical, systematic approach to the development of a mastitis control programme that could be used as a template for the development of control programmes for other infectious diseases in the dairy herd.
Saini, V; McClure, J T; Scholl, D T; DeVries, T J; Barkema, H W
Surveillance of antimicrobial use and resistance is needed to manage antimicrobial resistance in bacteria. In this study, data were collected on antimicrobial use and resistance in Staphylococcus aureus (n=562), isolated from intramammary infections and (sub)clinical mastitis cases on 89 dairy farms in 4 regions of Canada [Alberta, Ontario, Québec, and the Maritime Provinces (Prince Edward Island, Nova Scotia, and New Brunswick)]. Dairy producers were asked to deposit empty drug containers into specially provided receptacles, and antimicrobial drug use rate was calculated to quantify antimicrobial use. Minimum inhibitory concentrations were determined using the Sensititer bovine mastitis plate system (TREK Diagnostic Systems Inc., Cleveland, OH), containing antimicrobials commonly used for mastitis treatment and control. Multivariable logistic regression models were built to determine herd-level risk factors of penicillin, ampicillin, pirlimycin, penicillin-novobiocin combination, tetracycline and sulfadimethoxine resistance in Staph. aureus isolates. Intramammary administration of the penicillin-novobiocin combination for dry cow therapy was associated with penicillin and ampicillin resistance [odds ratio (OR): 2.17 and 3.10, respectively]. Systemic administration of penicillin was associated with penicillin resistance (OR: 1.63). Intramammary administration of pirlimycin for lactating cow mastitis treatment was associated with pirlimycin resistance as well (OR: 2.07). Average herd parity was associated with ampicillin and tetracycline resistance (OR: 3.88 and 0.02, respectively). Average herd size was also associated with tetracycline resistance (OR: 1.02). Dairy herds in the Maritime region had higher odds of penicillin and lower odds of ampicillin resistance than dairy herds in Québec (OR: 2.18 and 0.19, respectively). Alberta dairy herds had lower odds of ampicillin and sulfadimethoxine resistance than dairy herds in Québec (OR: 0.04 and 0.08, respectively
Græsbøll, Kaare; Kirkeby, Carsten Thure; Nielsen, Søren Saxmose
The future value of an individual dairy cow depends greatly on its projected milk yield. In developed countries with developed dairy industry infrastructures, facilities exist to record individual cow production and reproduction outcomes consistently and accurately. Accurate prediction...... of the future value of a dairy cow requires further detailed knowledge of the costs associated with feed, management practices, production systems, and disease. Here, we present a method to predict the future value of the milk production of a dairy cow based on herd recording data only. The method consists...... of several steps to evaluate lifetime milk production and individual cow somatic cell counts and to finally predict the average production for each day that the cow is alive. Herd recording data from 610 Danish Holstein herds were used to train and test a model predicting milk production (including factors...
Gillespie, B E; Headrick, S I; Boonyayatra, S; Oliver, S P
Coagulase-negative Staphylococcus species (CNS) were isolated from 11.3% (1407 of 12,412) of mammary quarter milk samples obtained from cows in three dairy research herds in 2005. Approximately 27% (383/1407) of CNS was identified to the species level. The species distribution among those CNS identified from all herds was Staphylococcus chromogenes (48%), Staphylococcus hyicus (26%), Staphylococcus epidermidis (10%), Staphylococcus simulans (7%), Staphylococcus warneri (2%), Staphylococcus hominis (2%), Staphylococcus saprophyticus (1%), Staphylococcus xylosus (1%), Staphylococcus haemolyticus (Staphylococcus sciuri (Staphylococcus intermedius (<1%). Staphylococcuschromogenes was the predominant CNS isolated from all three herds; however, differences were seen in the prevalence of other CNS species. A total of 158 CNS (S. chromogenesn=66, S. hyicusn=38, S. epidermidisn=37, S. simulans n=10, and S. warneri n=7) were analyzed by pulsed-field gel electrophoresis (PFGE). The majority (33/41) of CNS isolated from the same mammary quarter on more than one occasion had the same PFGE pattern indicating persistence of the same infection over time. When all PFGE patterns for each CNS were analyzed, no common pulsotype was seen among the three herds indicating that CNS are quite diverse. Composite milk somatic cell count (SCC) data were obtained +/-14d of when CNS were isolated. Average milk SCC (5.32 log(10)/ml) for cows in which CNS was the only bacteria isolated was significantly higher than the average milk SCC (4.90 log(10)/ml) from cows with quarter milk samples that were bacteriologically negative.
Anibal Eugênio Vercesi Filho
Full Text Available The Zebu breeds were introduced in Brazil mainly in the last century by imports from the Indian subcontinent. When the Zebu cattle arrived, the national herd suffered a significative change by backcrossing the national cows of taurine origin with Zebu sires. These processes created a polymorphism in the mitochondrial DNA (mtDNA in the Zebu animals with are in a major part derived from backcrossing and sharing mtDNA of taurine origin. To verify the maternal origin of cows belonging to the Dairy Gyr herd of APTA, Mococa 60 females were analyzed and 33 presented mtDNA from Bos taurus origin and 27 presented mtDNA from Bos indicus origin. None of these animals presented patterns of both mtDNA origins, indicating absence of heteroplasmy for these mitochondrial genotypes.
L. Cerqueira, Joaquim; Araújo, José P P; Blanco-Penedo, Isabel
We studied the relationship between behavior during milking with milking parlor management, measuring the occurrence of steps and kicks, and cow-related factors. We also investigated the link between stepping and kicking during milking and udder health. A total of 2,903 direct observations...... of milking behavior were collected in 44 dairy herds in the north of Portugal. The results showed great variability in the occurrence of stepping and kicking among herds during milking. Mixed linear and logistic regression models for factors associated with stepping and kicking were developed. Cows in tandem...... of the visit also showed a trend toward higher kicking frequency. The results suggest that animal welfare measures, like kicking and stepping, are suitable for epidemiologic studies. Significant interactions were observed when animals were affected by challenging health and welfare situations....
Cho, J; Tauer, L W; Schukken, Y H; Gómez, M I; Smith, R L; Lu, Z; Grohn, Y T
Johne's disease, or paratuberculosis, is a chronic infectious enteric disease of ruminants, caused by infection with Mycobacterium avium ssp. paratuberculosis (MAP). Given the absence of a fail-safe method of prevention or a cure, Johne's disease can inflict significant economic loss on the US dairy industry, with an estimated annual cost of over $200 million. Currently available MAP control strategies include management measures to improve hygiene, culling MAP serologic- or fecal-positive adult cows, and vaccination. Although the 2 first control strategies have been reported to be effective in reducing the incidence of MAP infection, the changes in herd management needed to conduct these control strategies require significant effort on the part of the dairy producer. On the other hand, vaccination is relatively simple to apply and requires minor changes in herd management. Despite these advantages, only 5% of US dairy operations use vaccination to control MAP. This low level of adoption of this technology is due to limited information on its cost-effectiveness and efficacy and some important inherent drawbacks associated with current MAP vaccines. This study investigates the epidemiological effect and economic values of MAP vaccines in various stages of development. We create scenarios for the potential epidemiological effects of MAP vaccines, and then estimate economically justifiable monetary values at which vaccines become economically beneficial to dairy producers such that a net present value (NPV) of a farm's net cash flow can be higher than the NPV of a farm using no control or alternative nonvaccine controls. Any vaccination with either low or high efficacy considered in this study yielded a higher NPV compared with a no MAP control. Moreover, high-efficacy vaccines generated an even higher NPV compared with alternative controls, making vaccination economically attractive. Two high-efficacy vaccines were particularly effective in MAP control and NPV
Aguilar, M; Hanigan, M D; Tucker, H A; Jones, B L; Garbade, S K; McGilliard, M L; Stallings, C C; Knowlton, K F; James, R E
herds that exceed target values for MUN when adhering to best management practices, which is consistent with the trend for differences in MUN among herds. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Mweu, Marshal M.; Nielsen, Søren S.; Hisham Beshara Halasa, Tariq
Contagious mastitis pathogens continue to pose an economic threat to the dairy industry. An understanding of their frequency and transmission dynamics is central to evaluating the effectiveness of control programmes. The objectives of this study were twofold: (1) to estimate the annual herd...... rate for S. agalactiae infection. Data covering the specified period, on bacteriological culture of all bulk tank milk samples collected annually as part of the mandatory Danish S. agalactiae surveillance scheme, were extracted from the Danish Cattle Database and subsequently analysed...
José Márcio Sbruzzi Cardoso
Full Text Available Neosporosis is one of the most important causes of abortion in both dairy and beef cattle in many countries. The objective of this study was to quantify the effect of Neospora caninum seropositivity on reproductive parameters in three dairy herds and the dynamics of anti-N. caninum antibodies during gestation in naturally infected cows. Blood samples from all animals were collected nine times on each of the three farms over a two-year period. Serum was tested for antibodies against N. caninum using the indirect fluorescent antibody test (IFAT with a cutoff value of 1:100. The relative risk of abortion between N. caninum-seropositive and seronegative cows varied between samplings at all farms, but there was only a statistically significant difference (P0.05 were found regarding gestational age at abortion, repeated abortion, number of inseminations for conception and calving intervals, between seropositive and seronegative cows on all the farms.
Sørensen, J.T.; Enevoldsen, Carsten; Houe, H.
A dynamic, stochastic model simulating the technical and economic consequences of bovine virus diarrhoea virus (BVDV) infections for a dairy cattle herd for use on a personal computer was developed. The production and state changes of the herd were simulated by state changes of the individual cows...... modelling principle. The validation problem in relation to the model was discussed. A comparison between real and simulated data using data from a published case report was shown to illustrate how user acceptance can be obtained....
Lundberg, Å; Nyman, A-K; Aspán, A; Börjesson, S; Unnerstad, H Ericsson; Waller, K Persson
Udder infections with Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis are common causes of bovine mastitis. To study these pathogens in early lactation, a 12-mo longitudinal, observational study was carried out in 13 herds with suboptimal udder health. The aims of the study were to investigate the occurrence of these pathogens and to identify if presence of the 3 pathogens, and of genotypes within the pathogens, differed with respect to herd, season, and parity. Quarter milk samples, collected at calving and 4 d in milk (DIM), were cultured for the 3 pathogens. Genotyping of staphylococcal and streptococcal isolates was performed using spa typing and pulsed-field gel electrophoresis, respectively. For each of the 3 pathogens, cows with an udder infection at calving or 4 DIM were allocated to 1 of 4 infection types: cleared (pathogen present only at calving), persistent (pathogen present in the same quarter at calving and 4 DIM), new (pathogen present only at 4 DIM), or cleared/new (pathogen present in 1 quarter at calving and in another quarter at 4 DIM). Associations between season or parity and overall occurrence of pathogens or infection types were determined using univariable mixed-effect logistic-regression models and the Fisher's exact test, respectively. The most commonly occurring pathogen was Staph. aureus, followed by Strep. dysgalactiae and Strep. uberis. Persistent infections were the most common infection type among Staph. aureus-infected cows, whereas cleared infections were the most common among Strep. dysgalactiae- and Strep. uberis-positive cows. The proportion of cows with persistent Staph. aureus infections and the proportion of cows having a Strep. uberis infection at calving or 4 DIM were higher in the multiparous cows than in primiparous cows. Infections with Strep. dysgalactiae were less common during the early housing season than during the late housing or pasture seasons, whereas persistent Strep. uberis
Hoffman, A C; Moore, D A; Wenz, J R; Vanegas, J
Monitoring herd lameness prevalence has utility for dairy producers and veterinarians in their efforts to reduce lameness, for animal welfare assessment programs, and for researchers. Locomotion scoring is a method used to quantify lameness and calculate prevalence. Because of the time necessary to locomotion score each cow in large dairy herds, a sampling strategy to determine herd lameness prevalence that allows scoring of fewer cows would be useful. Such a sampling strategy must be validated for accuracy compared with the lameness prevalence when all cows in a herd are locomotion scored. The purpose of this study was to assess 3 previously suggested methods of estimating lameness prevalence by strategic sampling of dairy herds. Sampling strategies tested included (1) sampling a calculated number of cows in the middle third of the milking parlor exit order for each pen, (2) sampling a calculated number of cows weighted across pens and distributed evenly within each pen, and (3) sampling all cows in the high production, low production, and hospital pens. Lactating cows on 5 dairy farms in Washington and Oregon (n=4,422) were locomotion scored using a 5-point scale to determine herd-level lameness prevalence (percentage with locomotion score ≥3). Milking parlor exit order, order in headlocks at the feed bunk within each pen, and breed were recorded for each cow. The number of days in lactation, milk production, and parity were collected from farm computer records. Pen grouping strategy for each farm was obtained by interview with farm management. Sampling strategies were modeled using the locomotion score data set for each herd. Estimates of lameness prevalence obtained from the milking parlor exit order sample and the sample distributed across pens were within 5 percentage points of the whole herd prevalence. The third strategy estimated the lameness prevalence within 5 percentage points on 4 farms, but overestimated prevalence on 1 farm. Pen-level prevalence
ESTRATEGIC MANAGEMENT DURING THE TRANSICION PERIOD TO OPTIMISE PRODUCTIVITY AND REPRODUCTIVE PERFORMANCE IN THE DAIRY HERD
MANEJO ESTRATÉGICO DURANTE EL PERIODO DE TRANSICIÓN PARA OPTIMIZAR LA PRODUCCIÓN Y EL COMPORTAMIENTO REPRODUCTIVO GANADO LECHERO
In dairy herds, the interval between calving and pregnancy depend on many factors including preparation of the cow for calving, dietary management before and after calving. Factors such as hypocalcemia and body condition are determinant in the presentation of postpartum pathologies and ovarian activity resumption. Additionally, management of the dairy cattle should include fixed time artificial insemination protocols to increase the number of animals bred close to the voluntary waiting period...
Warnick, L.D.; Nielsen, L.R.; Nielsen, Jens
The Danish government and cattle industry instituted a Salmonella surveillance program in October 2002 to help reduce Salmonella enterica subsp. enterica serotype Dublin (S. Dublin) infections. All dairy herds are tested by measuring antibodies in bulk tank milk at 3-month intervals. The program...... is based on a well-established ELISA, but the overall test program accuracy and misclassification was not previously investigated. We developed a model to simulate repeated bulk tank milk antibody measurements for dairy herds conditional on true infection status. The distributions of bulk tank milk...
Hall, J; Wapenaar, W
The objective was to compare farm veterinary surgeons' and dairy farmers' opinions on herd health plans and herd health and production management with the aim of discovering and better understanding the differences. Two comparable questionnaires, one for farm veterinarians and one for dairy farmers, were distributed throughout the UK. While listing the 'major roles' of the veterinarian on the farm, veterinarians considered 'optimising milk production', 'decreasing overall cost' and 'being an independent adviser' as important roles, but these were not seem to be perceived as such by the farmers. In addition, when presenting themselves to clients, veterinarians seemed to favour the 'friend of the farmer' approach; a much smaller proportion of farmers seemed to prefer this approach. The majority of farm respondents (98 of 121; 81 per cent) valued the discussions with their veterinarian, and it was apparent from the relatively small proportion of veterinarians instigating a discussion on farm (33 of 125; 26 per cent) that there is the opportunity for a more proactive approach from veterinarians. The study underlines that 'demonstrating cost-effectiveness' is still a main concern for veterinarians and farmers and identifies areas that can be improved by more training and effective communication.
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.
Græsbøll, Kaare; Kirkeby, Carsten Thure; Nielsen, Søren Saxmose
of the future value of a dairy cow requires further detailed knowledge of the costs associated with feed, management practices, production systems, and disease. Here, we present a method to predict the future value of the milk production of a dairy cow based on herd recording data only. The method consists......The future value of an individual dairy cow depends greatly on its projected milk yield. In developed countries with developed dairy industry infrastructures, facilities exist to record individual cow production and reproduction outcomes consistently and accurately. Accurate prediction...... of somatic cell count. We conclude that estimates of future average production can be used on a day-to-day basis to rank cows for culling, or can be implemented in simulation models of within-herd disease spread to make operational decisions, such as culling versus treatment. An advantage of the approach...
Full Text Available Abstract Background Body condition score and blood profiles have been used to monitor management and herd health in dairy cows. The aim of this study was to examine BCS and extended metabolic profiles, reflecting both energy metabolism and liver status around calving in high-producing herds with a high incidence of abomasal displacement and ketosis and to evaluate if such profiles can be used at herd level to pinpoint specific herd problems. Methods Body condition score and metabolic profiles around calving in five high-producing herds with high incidences of abomasal displacement and ketosis were assessed using linear mixed models (94 cows, 326 examinations. Cows were examined and blood sampled every three weeks from four weeks ante partum (ap to nine weeks postpartum (pp. Blood parameters studied were glucose, fructosamine, non-esterified fatty acids (NEFA, insulin, β-hydroxybutyrate, aspartate aminotransferase, glutamate dehydrogenase, haptoglobin and cholesterol. Results All herds had overconditioned dry cows that lost body condition substantially the first 4–6 weeks pp. Two herds had elevated levels of NEFA ap and three herds had elevated levels pp. One herd had low levels of insulin ap and low levels of cholesterol pp. Haptoglobin was detected pp in all herds and its usefulness is discussed. Conclusion NEFA was the parameter that most closely reflected the body condition losses while these losses were not seen in glucose and fructosamine levels. Insulin and cholesterol were potentially useful in herd profiles but need further investigation. Increased glutamate dehydrogenase suggested liver cell damage in all herds.
Stengärde, Lena; Tråvén, Madeleine; Emanuelson, Ulf; Holtenius, Kjell; Hultgren, Jan; Niskanen, Rauni
Background Body condition score and blood profiles have been used to monitor management and herd health in dairy cows. The aim of this study was to examine BCS and extended metabolic profiles, reflecting both energy metabolism and liver status around calving in high-producing herds with a high incidence of abomasal displacement and ketosis and to evaluate if such profiles can be used at herd level to pinpoint specific herd problems. Methods Body condition score and metabolic profiles around calving in five high-producing herds with high incidences of abomasal displacement and ketosis were assessed using linear mixed models (94 cows, 326 examinations). Cows were examined and blood sampled every three weeks from four weeks ante partum (ap) to nine weeks postpartum (pp). Blood parameters studied were glucose, fructosamine, non-esterified fatty acids (NEFA), insulin, β-hydroxybutyrate, aspartate aminotransferase, glutamate dehydrogenase, haptoglobin and cholesterol. Results All herds had overconditioned dry cows that lost body condition substantially the first 4–6 weeks pp. Two herds had elevated levels of NEFA ap and three herds had elevated levels pp. One herd had low levels of insulin ap and low levels of cholesterol pp. Haptoglobin was detected pp in all herds and its usefulness is discussed. Conclusion NEFA was the parameter that most closely reflected the body condition losses while these losses were not seen in glucose and fructosamine levels. Insulin and cholesterol were potentially useful in herd profiles but need further investigation. Increased glutamate dehydrogenase suggested liver cell damage in all herds. PMID:18687108
Bianchini, Valentina; Borella, Laura; Benedetti, Valentina; Parisi, Antonio; Miccolupo, Angela; Santoro, Eliana; Recordati, Camilla; Luini, Mario
Thermotolerant Campylobacter spp. are frequently the cause of human gastroenteritis and have assumed more importance in Italy following the increased consumption of raw milk. Our objectives were to determine the prevalence and genotypes of Campylobacter spp. in dairy herds and to investigate the possible sources of bulk milk contamination. Bulk milk from dairy herds (n = 282) was cultured for Campylobacter spp. and Enterobacteriaceae. At three Campylobacter jejuni-positive farms, bovine feces, pigeon intestines, milk, and water points were also investigated. Isolates were identified by PCR and genotyped using multilocus sequence typing (MLST). C. jejuni was detected in 34 (12%) bulk milk samples. The strains belonged to 14 sequence types, and the most common clonal complexes were CC-21, CC-48, and CC-403. No association was demonstrated between the presence of C. jejuni and high levels of Enterobacteriaceae in bulk milk. At the three farms examined, C. jejuni was isolated from bovine feces (25/82 [30.5%]), pigeon intestines (13/60 [21.7%]), bulk milk (10/24 [41.7%]), and water points (4/16 [25%]). MLST revealed lineages that were common between milk and bovine feces but distinct between cattle and pigeons. In one herd, C. jejuni with the same genotype was isolated repeatedly from bulk milk and a cow with an udder infection. Our results showed a high prevalence of C. jejuni in bulk milk and suggested that udder excretion, in addition to fecal matter, may be a route of bulk milk contamination. MLST analysis indicated that pigeons are probably not relevant for the transmission of C. jejuni to cattle and for milk contamination.
Tikofsky, L L; Zadoks, R N
Group G streptococci in animals usually belong to the species Streptococcus canis and are most commonly found in dogs and cats. Occasionally, Strep. canis is detected in milk from dairy cows. An outbreak of Strep. canis mastitis in a dairy herd is described. Based on results from bacterial culture and ribotyping, a cat with chronic sinusitis was the most likely source of the outbreak. Subsequent cow-to-cow transmission of Strep. canis was facilitated by poor udder health management, including...
Sepulveda, N.G.; Risopatron, J.; Rodriguez, F.; Perez, E.
The objective of this study was to identify causes of inefficiency in Artificial Insemination (AI) services in 12 dairy farms located in southern Chile. Milk progesterone concentration was determined on the day of breeding and then 10-12 and 21-22 days after AI. Data for semen and cow inseminated, including physical signs of oestrus, were recorded in a computer database (AIDA). Information from 713 cows with first services was analysed. The mean interval from calving to first service was 88.7 days and the mean interval from calving to conception was 107.9 days. The conception rate at first service was 61.9%. Incidence of incorrect AI, most likely due to erroneous heat detection, was 8.9%. Herd related problems affected efficiency of AI in 15.2%. The results show that important factors affecting reproductive performance include nutritional management, oestrus detection and AI technique. (author)
Ivemeyer, S.; Smolders, E.A.A.; Brinkmann, J.; Gratzer, E.; Hansen, B.; Henriksen, B.I.F.; Huber, J.; Leeb, C.; March, S.; Mejdell, C.; Nicholas, P.; Roderick, S.; Stöger, E.; Vaarst, M.; Whistance, L.K.; Winckler, C.; Walkenhorst, M.
Achieving and maintaining high herd health and welfare status and low veterinary medicine inputs are important aims in organic livestock farming. Therefore, an on-farm intervention study (CORE Organic ANIPLAN) was conducted on 128 organic dairy farms in seven European countries aiming at minimising
Piepers, S.; Peeters, K.; Opsomer, G.; Barkema, H.W.; Frankena, K.; Vliegher, de S.
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
Nielsen, Torben Dahl; Green, L. E.; Kudahl, Anne Margrethe Braad
The effect of Salmonella on milk production is not well established in cattle. The objective of this study was to investigate whether introduction of Salmonella into dairy cattle herds was associated with reduced milk yield and determine the duration of any such effect. Longitudinal data from 2005...
Foddai, Alessandro; Stockmarr, Anders; Boklund, Anette
The temporal sensitivity of the surveillance system (TemSSe) for Bovine Viral Diarrhea (BVD) in Danish dairy herds was evaluated. Currently, the Danish antibody blocking ELISA is used to test quarterly bulk tank milk (BTM). To optimize the surveillance system as an early warning system, we...
Jalvingh, A.W.; Arendonk, van J.A.M.; Dijkhuizen, A.A.; Renkema, J.A.
A dynamic probabilistic simulation model is further extended and used for a comparison of different strategies in order to change the calving pattern of a herd. The Markov chain approach is used to simulate herd dynamics. Strategies to change the calving pattern focusing on the farm's intake of
Nielsen, C; Østergaard, Søren; Emanuelson, U
The main aim was to assess the impact of mastitis on technical and economic results of a dairy herd under current Swedish farming conditions. The second aim was to investigate the effects obtained by withdrawing milk with high somatic cell count (SCC). A dynamic and stochastic simulation model, Sim......Herd, was used to study the effects of mastitis in a herd with 150 cows. Results given the initial incidence of mastitis (32 and 33 clinical and subclinical cases per 100 cow-years, respectively) were studied, together with the consequences of reducing or increasing the incidence of mastitis by 50%, modelling...... no clinical mastitis (CM) while keeping the incidence of subclinical mastitis (SCM) constant and vice versa. Six different strategies to withdraw milk with high SCC were compared. The decision to withdraw milk was based on herd-level information in three scenarios: withdrawal was initiated when the predicted...
Stygar, Anna Helena; Krogh, Mogens Agerbo; Kristensen, Troels
Evolutionary operations is a method to exploit the association of often small changes in process variables, planned during systematic experimentation and occurring during the normal production flow, to production characteristics to find a way to alter the production process to be more efficient...... from a herd, and an intervention effect on a given day. The model was constructed to handle any number of cows, experimental interventions, different data sources, or presence of control groups. In this study, data from 2 commercial Danish herds were used. In herd 1, data on 98,046 and 12,133 milkings...... tank records. The presented model proved to be a flexible and dynamic tool, and it was successfully applied for systematic experimentation in dairy herds. The model can serve as a decision support tool for on-farm process optimization exploiting planned changes in process variables and the response...
Full Text Available There are many factors that can influence reproduction of the dairy cow such as management, physiologic factors, nutrition, genetics, and diseases Reproductive efficiency. Reproductive performance is therefore a major concern in dairy herds to success, and it has to be subject of continuous and accurate evaluation in reproductive herd health programs, in order to detect problems and implement adequate solutions. Controlled breeding programs have allowed dairy producers to optimize service rate with little impact on conception and pregnancy losses in lactating dairy cows.Existen muchos factores que pueden influenciar la reproduccion en ganaderías de leche, tales como el manejo, factores fisiológicos, la nutrición, genéticos, y la presentación de enfermedades, entre otros. Por esta razon la eficiencia reproductiva es de gran importancia en las ganaderías para ser exitosas y debe ser continua y adecuadamente evaluada en los programas reproductivos de salud de hato, con el fin de detectar los problemas y establecer las soluciones adecuadas. Los programas de reproduccion controlados, han permitido a los productores optimizar las tasas de servicios con un muy pequeño impacto en las tasas de concepción y perdida gestacional en ganaderías de leche.
Gussmann, Maya Katrin; Græsbøll, Kaare; Toft, Nils
Societal pressure to limit the use of antibiotics in livestock production systems, including dairy cattle systems, is consistently increasing. To motivate farmers to reduce antibiotic usage, it is important to understand the factors that determine whether a cow will be treated with antibiotics...... on these factors. The resulting regression coefficients of 422 herds were further analyzed by principal component analysis and clustering to determine the driving predictors for treatment in different groups of farms. The results showed that determinants that were most important for predicting antibiotic...... treatments vary from one farm to another. Health indicators such as PCR or somatic cell count were most indicative for treatment on some farms, whereas other groups seemed to depend more on production factors (milk yield) or later culling of the cows. This shows that farmers behave differently...
Larsen, H. D.; Sloth, K. H.; Elsberg, C.
The aim of the present study was to examine the diversity of Staphylococcus aureus isolates from bovine intramammary infections (IMI) in nine dairy herds, and compare these with isolates from other sites on the cows by phage- and ribotyping. Whether colonisation of milkers with S. aureus could...... be a source of infection for bovine IMI was investigated. In addition, 100 epidemiologically unrelated S. aureus isolates from asymptomatic human carriers were also phage- and ribotyped to compare the human and bovine reservoir of S. aureus in Denmark. A total of 625 S. aureus isolates from bovine IMI, bovine......, there was a close correspondence between ribo- and phage types of S. aureus isolated from bovine intramammmary infections and skin lesions. Isolates from milking personnel, however, were not identical to any of the predominant intramammary strains. Furthermore, several of the isolates from milking personnel showed...
Clovis Laurindo Silva
Full Text Available Neospora caninum is a coccidian protozoan that affects cattle worldwide causing economic losses. To survey the frequency of anti-N. caninum antibodies in dairy herds in the municipality of Parauapebas, Southeast of Pará, samples of 465 sera from 45 farms were subjected to indirect immunofluorescence assay (cutoff 1:100. Anti-N. caninum antibodies were found with a frequency of 13,33% with the following titer distribution: 27 (43,55% for titer 100; 14 (22,58% for 200; 16 (25,80% for 400, and 5 (8,07% for 800; no serum titers more than 800 was noted, but at least one positive animal was present in most farms. The highest frequency occurred among females, with no significant difference in frequency between the sexes (Fisher exact test = 0,59, P = 0,99; 2-year-old animals had the highest frequency, although their numbers were lesser than those aged >5 years, with no significant difference in frequency between the age groups (?2 = 2,1, P = 0,71. No significant difference was observed between the frequency and occurrence of abortion (?2 = 2,3, P = 0,13 and frequency and presence of dogs in the farms (?2 = 0,26, P = 0,60. Actions toward health monitoring are recommended to prevent the entry of new sources of N. caninum and to control its spread within herds.
Randall, L V; Green, M J; Green, L E; Chagunda, M G G; Mason, C; Archer, S C; Huxley, J N
It has been demonstrated that low body condition and previous occurrence of lameness increase the risk of future lameness in dairy cows. To date the population attributable fraction (PAF), which provides an estimate of the contribution that a risk factor makes toward the total number of disease events in a population, has not been explored for lameness using longitudinal data with repeated measures. Estimation of PAF helps to identify control measures that could lead to the largest improvements on-farm. The aim of this study was to use longitudinal data to evaluate the proportion of lameness that could be avoided in 2 separate herds (2 populations) through (1) reduced recurrence of previous lameness events, (2) and moving body condition score (BCS) into more optimal ranges. Data were obtained from 2 UK dairy herds: herd A, a 200-cow herd with 8 yr of data from a total of 724 cows where lameness events were based on weekly locomotion scores (LS; 1 to 5 scale), and herd B, a 600-cow herd with data recorded over 44 mo from a total of 1,040 cows where treatment of clinical cases was used to identify lameness events. The PAF for categories of BCS were estimated using a closed equation appropriate for multiple exposure categories. Simulation models were used to explore theoretical scenarios to reflect changes in BCS and recurrence of previous lameness events in each herd. For herd A, 21.5% of the total risk periods (cow-weeks) contained a lameness event (LS 3, 4, or 5), 96% of which were repeat events and 19% were recorded with BCS events were based on 2 consecutive weeks of LS 4 or 5, 4% of risk periods were recorded as lame, of which 89.5% were repeat events. For herd B, 16.3% of the total risk periods (consecutive 30 d) contained a lameness event (72.6% were repeat events) and 20% were recorded with BCS ≤2 (0 to 120 d previously). The median PAF for all previous lameness was between 79 and 83% in the 2 herds. Between 9 and 21% of lameness events could be attributed
Cremonesi, P; Pozzi, F; Raschetti, M; Bignoli, G; Capra, E; Graber, H U; Vezzoli, F; Piccinini, R; Bertasi, B; Biffani, S; Castiglioni, B; Luini, M
Staphylococcus aureus is one of the most important causes of mastitis in dairy cattle. Based on previous research, Staph. aureus genotypes with different pathogenic and contagious properties can cause intramammary infection (IMI) and coexist in the same herd. Our study aimed to compare Staph. aureus strains from herds that differed in IMI prevalence using different molecular approaches such as ribosomal spacer (RS)-PCR, multilocus sequence typing (MLST), spa typing, ribotyping, pulsed-field gel electrophoresis (PFGE), and multiplex PCR. For this purpose, 31 dairy herds with Staph. aureus IMI were selected, and 16 of these were chosen for a comparison study: the 8 high-prevalence (HP) herds had Staph. aureus IMI prevalence >28% and the 8 low-prevalence (LP) herds had an IMI prevalence Staph. aureus from mammary quarters of all positive cows were genotyped with RS-PCR, a technique based on amplification of a portion of the intergenic spacer 16S-23S rRNA, and a subset of 54 strains was also analyzed by multiplex PCR, ribotyping, PFGE, MLST, and spa typing. The RS-PCR analysis revealed 12 different profiles. Staphylococcus aureus strains isolated from 5 out of 8 HP herds showed a profile identical to the genotype B (GTB), described in previous studies as being strongly associated with high within-herd prevalence of Staph. aureus mastitis and the presence of the genes coding for enterotoxins sea, sed, and sej, a long x-region of spa gene, and 3 lukE fragments. Moreover, all strains isolated in the HP herds possessed genes coding for staphylococcal enterotoxins. In LP herds, a limited number of strains of 6 genotypes, different from those isolated in HP herds, were identified and GTB was not found. Within these genotypes, 4 strains were positive for the mecA gene. Preliminary results and comparison with other genotyping methods confirmed that genotyping by RS-PCR is an accurate, rapid, and inexpensive tool for future field studies on Staph. aureus mastitis strains and
Full Text Available Abstract Driven by consumer demands, European legislation has suggested the use of HACCP (Hazard Analysis Critical Control Point as the quality risk management programme for the whole dairy chain. Until now, an exception has been made for primary producers, but as regulations evolve, on-farm HACCP-like programmes should be ready to assure food safety as well as animal health and animal welfare. In our field experiment, the HACCP-concept was used to combine both optimal farm management and formalisation of quality assurance in an on-farm situation in the Netherlands. The process of young stock rearing was chosen, since its importance for the future of the farm is often underestimated. Hazards and their associated risk factors can be controlled within the farm-specific standards and tolerances, as targets can be controlled by corrective measures and by implementation of farm-specific worksheets. The veterinarian is pivotal for the facility-based HACCP team, since he/she has knowledge about on-farm risk assessment and relations between clinical pathology, feed and farm management. The HACCP concept in combination with veterinary herd health and production management programmes offers a promising approach to optimise on-farm production processes (i.e., young stock rearing in addition to a structural approach for quality risk management on dairy farms.
Barkallah, Mohamed; Slima, Ahlem Ben; Mallek, Zouhir; Gautier, Michel; Greub, Gilbert; Gdoura, Radhouane; Fendri, Imen
Bovine abortion of unknown infectious etiology still remains a major economic problem. Thus, we investigated whether Brucella spp., Listeria monocytogenes, Salmonella spp., Campylobacter spp. and Coxiella burnetii are associated with abortion and/or stillbirth in Tunisian dairy cattle. Using a pan-Chlamydiales PCR, we also investigated the role of Chlamydiaceae, Waddlia chondrophila, Parachlamydia acanthamoebae and other members of the Chlamydiales order in this setting. Veterinary samples taken from mid to late-term abortions from twenty dairy herds were tested. From a total of 150 abortion cases collected, infectious agents were detected by PCR in 73 (48.66%) cases, 13 (8.66%) of which represented co-infections with two infectious agents. Detected pathogens include Brucella spp (31.3%), Chlamydiaceae (4.66%), Waddlia chondrophila (8%), Parachlamydia acanthamoebae (5.33%), Listeria monocytogenes (4.66%) and Salmonella spp. (3.33%). In contrast, Campylobacter spp. and Coxiella burnetii DNA were not detected among the investigated veterinary samples. This demonstrates that different bacterial agents may cause bovine abortion in Tunisia. This is the first report suggesting the role of Parachlamydia acanthamoebae in bovine abortion in Africa. Further studies with a larger number of samples are necessary to confirm whether this emerging pathogen is directly linked to abortion in cattle. PMID:24662769
Driven by consumer demands, European legislation has suggested the use of HACCP (Hazard Analysis Critical Control Point) as the quality risk management programme for the whole dairy chain. Until now, an exception has been made for primary producers, but as regulations evolve, on-farm HACCP-like programmes should be ready to assure food safety as well as animal health and animal welfare. In our field experiment, the HACCP-concept was used to combine both optimal farm management and formalisation of quality assurance in an on-farm situation in the Netherlands. The process of young stock rearing was chosen, since its importance for the future of the farm is often underestimated. Hazards and their associated risk factors can be controlled within the farm-specific standards and tolerances, as targets can be controlled by corrective measures and by implementation of farm-specific worksheets. The veterinarian is pivotal for the facility-based HACCP team, since he/she has knowledge about on-farm risk assessment and relations between clinical pathology, feed and farm management. The HACCP concept in combination with veterinary herd health and production management programmes offers a promising approach to optimise on-farm production processes (i.e., young stock rearing) in addition to a structural approach for quality risk management on dairy farms. PMID:21851722
Taylor, R.T.; Barnabe, R.C.; Morales, J.R.
The review describes the commonly practised systems of milk production in sample countries within the five major topographical/climatological subregions of Latin America, viz. Central America, the Caribbean, the South American subtropics, the Andes and the Temperate Zone. The state of development and importance of the dairy industry to the economy of each country are discussed. Production and reproduction indices are quoted, as are the genetic make-up of the dairy herds, husbandry practices and the quality of livestock management. It is clear that there is an enormous capacity for improvement in the efficiency of milk production systems in the Latin American region as a whole; to achieve this improvement, there is an urgent need to pursue on-farm based research aimed at identifying constraints to the performance of dairy cattle and the implementation of low cost management/nutritional/health control measures. (author)
Gelasakis, A I; Angelidis, A S; Giannakou, R; Filioussis, G; Kalamaki, M S; Arsenos, G
The objectives of this study were (1) to record the major pathogens associated with subclinical mastitis (SCM), (2) to calculate their incidence during the milking period, and (3) to estimate the effect of SCM on daily milk yield (DMY) for goats reared under low-input management schemes. Dairy goats (n=590) of Skopelos and indigenous Greek breeds from 4 herds were randomly selected for the study. The study included monthly monitoring, milk yield recording, and bacteriological analyses of milk of individual goats during the course of 2 successive milking periods. Incidence and cumulative incidence were calculated for SCM cases. Moreover, 2 mixed linear regression models were built to assess the effects of (1) SCM and (2) different pathogens isolated from SCM cases, on DMY. The estimated incidence and cumulative incidence of SCM for the first and the second year of the study were 69.5 and 96.4 new cases of SCM/1,000 goat-months, and 24.1 and 31.7%, respectively. A total of 755 milk samples were subjected to microbiological examination, resulting in 661 positive cultures. Coagulase-negative and coagulase-positive staphylococci were isolated from 50.2 and 34.5% of the positive cultures, respectively. The incidence of infections (new infections per 1,000 goat-months) for the first and the second year of the study were 34 and 53 for coagulase-negative staphylococci, 23 and 28 for coagulase-positive staphylococci, 3 and 5 for Streptococcus/Enterococcus spp., and 5.5 and 9.1 for gram-negative bacteria. Goats with SCM had lower DMY when compared with goats without SCM (ca. 47g/d, corresponding to a 5.7% decrease in DMY). In particular, goats with SCM due to coagulase-positive staphylococci infection produced approximately 80g/d less milk (a reduction of ca. 9.7%) compared with uninfected ones, whereas SCM due to gram-negative bacteria resulted in approximately 15% reduction in DMY. Investigating the epidemiology of SCM and its effects on production traits is critical for
Bennedsgaard, Torben W.; Thamsborg, Stig M.; Aarestrup, Frank Møller
Background: Quarter milk samples from cows with high risk of intramammary infection were examined to determine the prevalence of Staphylococcus aureus (SA) and penicillin resistant SA (SAr) in conventional and organic dairy herds and herds converting to organic farming in a combined longitudinal...... and cross-sectional study. Methods: 20 conventional herds, 18 organic herds that converted before 1995, and 19 herds converting to organic farming in 1999 or 2000 were included in the study. Herds converting to organic farming were sampled three times one year apart; the other herds were sampled once. Risk......: 2%-5%) respectively. The prevalence of penicillin resistance among SA infected cows was 12% (95% confidence interval: 6%-19%) when calculated from the first herd visits. No statistically significant differences were observed in the prevalence of SAr or the proportion of isolates resistant...
Sørensen, J.T.; Enevoldsen, Carsten; Houe, H.
A dynamic, stochastic model simulating the technical and economic consequences of bovine virus diarrhoea virus (BVDV) infections for a dairy cattle herd for use on a personal computer was developed. The production and state changes of the herd were simulated by state changes of the individual cows...... variables describing biologic and management variables including 21 decision variables describing the effect of BVDV infection on the production of the individual animal. Two markedly different scenarios were simulated to demonstrate the behaviour of the developed model and the potentials of the applied...
Nobrega, Diego B; De Buck, Jeroen; Naqvi, S Ali; Liu, Gang; Naushad, Sohail; Saini, Vineet; Barkema, Herman W
Assessment of antimicrobial use (AMU) is vital for interpreting the origin of changes in antimicrobial resistance (AMR). The objectives of the present study were to estimate the association between AMU determined using on-farm treatment records (TR) and inventory of empty drug containers (INV). Herds were selected to represent Canadian dairy farms. Producers were asked to record animal health events and treatments on a standard General Health Event form. For inventory data, 40-L receptacles were placed at various locations considered convenient to deposit all empty drug containers. Antimicrobial defined-daily dosages (ADD) were calculated for 51 Canadian herds using the 2 methods. Estimation of AMU was 31,840 ADD using the INV and 14,487 ADD using the TR, indicating that for every TR entry, 2.20 times more treatments were observed using the INV. Mastitis, reproductive conditions, and dry cow therapy were the most frequent reasons for antimicrobial therapy when assessing TR. For all antimicrobials evaluated, mean ADD was higher using the INV versus TR. Regardless, a strong positive correlation (0.80) was observed between the 2 methods, indicating that herds with increased number of ADD recorded using the INV also had increased number of ADD recorded using TR. Furthermore, a positive association was observed for the 6 most commonly used antimicrobials. In comparison to methods used in surveillance programs on AMU in livestock that assume a constant use in all herds (i.e., sales data), INV provided a herd-level specific quantity of AMU positively correlated with AMU recorded at the animal level in general. The INV was easy to implement and provided a measure of total AMU in the herd. Availability of such information would be valuable for interpreting changes in AMR at the herd level and enabling evaluation of interventions for decreasing AMR. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Krpálková, L; Cabrera, V E; Kvapilík, J; Burdych, J; Crump, P
The objective of this study was to evaluate the associations of variable intensity in rearing dairy heifers on 33 commercial dairy herds, including 23,008 cows and 18,139 heifers, with age at first calving (AFC), average daily weight gain (ADG), and milk yield (MY) level on reproduction traits and profitability. Milk yield during the production period was analyzed relative to reproduction and economic parameters. Data were collected during a 1-yr period (2011). The farms were located in 12 regions in the Czech Republic. The results show that those herds with more intensive rearing periods had lower conception rates among heifers at first and overall services. The differences in those conception rates between the group with the greatest ADG (≥0.800 kg/d) and the group with the least ADG (≤0.699 kg/d) were approximately 10 percentage points in favor of the least ADG. All the evaluated reproduction traits differed between AFC groups. Conception at first and overall services (cows) was greatest in herds with AFC ≥800 d. The shortest days open (105 d) and calving interval (396 d) were found in the middle AFC group (799 to 750 d). The highest number of completed lactations (2.67) was observed in the group with latest AFC (≥800 d). The earliest AFC group (≤749 d) was characterized by the highest depreciation costs per cow at 8,275 Czech crowns (US$414), and the highest culling rate for cows of 41%. The most profitable rearing approach was reflected in the middle AFC (799 to 750 d) and middle ADG (0.799 to 0.700 kg) groups. The highest MY (≥8,500 kg) occurred with the earliest AFC of 780 d. Higher MY led to lower conception rates in cows, but the highest MY group also had the shortest days open (106 d) and a calving interval of 386 d. The same MY group had the highest cow depreciation costs, net profit, and profitability without subsidies of 2.67%. We conclude that achieving low AFC will not always be the most profitable approach, which will depend upon farm
Jenko, J; Gorjanc, G; Kovač, M; Ducrocq, V
Survival analysis techniques for sire-maternal grandsire (MGS) and animal models were used to test the genetic evaluation of longevity in a Slovenian Brown cattle population characterized by small herds. Three genetic models were compared: a sire-MGS model for bulls and an approximate animal model based on estimated breeding values (EBV) from the sire-MGS model for cows, an animal model, and an animal model based on the estimated variance components from the sire-MGS model. In addition, modeling the contemporary group effect was defined as either a herd or a herd-year (HY) effect. With various restrictions on the minimum HY group size (from 1 to 10 cows per HY), changes in estimates of variance components, and consequently also in EBV, were observed for the sire-MGS and animal models. Variance of contemporary group effects decreased when an HY effect was fitted instead of a herd effect. In the case of a sire-MGS model, estimates of additive genetic variance were mostly robust to changes in minimum HY group size or fitting herd or HY effect, whereas they increased in the animal model when HY instead of herd effects was fitted, possibly revealing some confounding between cow EBV and contemporary group effect. Estimated heritabilities from sire-MGS models were between 0.091 and 0.119 and were mainly influenced by the restriction on the HY group size. Estimated heritabilities from animal models were higher: between 0.125 and 0.160 when herd effect was fitted and between 0.171 and 0.210 when HY effect was fitted. Rank correlations between the animal model and the approximate animal model based on EBV from the sire-MGS model were high: 0.94 for cows and 0.93 for sires when a herd effect was fitted and 0.90 for cows and 0.93 for sires when an HY effect was fitted. Validation performed on the independent validation data set revealed that the correlation between sire EBV and daughter survival were slightly higher with the approximate animal model based on EBV from the sire
Dijkhuizen, A.A.; Stelwagen, J.; Renkema, J.A.
A stochastic simulation model was developed to study management decisions in dairy herds. The primary purpose of this model is to quantify the economic effects of different culling policies with respect to productive and reproductive failure. Each stimulated herd consists of a fixed number of up
Bennedsgaard, Torben W.; Thamsborg, Stig M.; Aarestrup, Frank Møller
Background: Quarter milk samples from cows with high risk of intramammary infection were examined to determine the prevalence of Staphylococcus aureus (SA) and penicillin resistant SA (SAr) in conventional and organic dairy herds and herds converting to organic farming in a combined longitudinal ...
A questionnaire-based survey on veterinary herd health and production management services was conducted on 194 specialist dairy veterinarians and 466 dairy farmers. The farmers were randomly selected from greater than 6,000 farmer clients of the surveyed veterinarians. This paper reports these survey findings and the findings of an earlier survey conducted among the veterinarians. The survey included questions on the attributes of the service itself, the practitioners delivering the service, reasons for participation and the expected future of herd health and production management services. Reasons farmers participated in herd health and production management programmes included; access to routine screening of their herd; increasing profits; and receiving regular veterinary advice or solutions to remedy existing problems. Advantages of participation named included: good management support; higher profits; structural solutions to problems; and being better informed. Differences between farming styles were observed, pointing to the different needs and goals of farming styles. Farmers cited high costs and the time investment required as major disadvantages. The proportion of farmers citing these reasons was lower than expected by the veterinarians. In the future, preventive healthcare will be the main reason of farmers to participate. Farmers who are not using the service can potentially be encouraged to engage the services after gaining increased insight into the herd health and management service structure, the planning of activities, the cost-benefit of the service, veterinary surgeons being more co-operative with other farm advisors and veterinarians being more willing to pay attention to quality issues on the dairy farm. PMID:21851703
Ivemeyer, S; Smolders, G; Brinkmann, J
medicine use through animal health and welfare planning (AHWP). Medicine use (excluding complementary treatments such as homeopathic remedies) was assessed as the total number of treatments and as the number of treatments of various disease categories (udder, fertility, metabolism, locomotion and others......Achieving and maintaining high herd health and welfare status and low veterinary medicine inputs are important aims in organic livestock farming. Therefore, an on-farm intervention study (CORE Organic ANIPLAN) was conducted on 128 organic dairy farms in seven European countries aiming at minimising...... be regarded as a feasible approach to minimising medicine use without the impairment of production and herd health under several organic dairy farming conditions in Europe....
Sergeant, E.S.G.; Nielsen, Søren S.; Toft, Nils
-sensitivity and specificity; use of a distribution of observed values (rather than a fixed, low value) for design prevalence; and estimates of the probability of low prevalence (Pr-Low) based on a specific number of test-positive animals, rather than for a result less than or equal to a specified cut-point number of reactors...... of this study was to develop a method to estimate the probability of low within-herd prevalence of paratuberculosis for Danish dairy herds. A stochastic simulation model was developed using the R(R) programming environment. Features of this model included: use of age-specific estimates of test....... Using this model, five herd-testing strategies were evaluated: (1) milk-ELISA on all lactating cows; (2) milk-ELISA on lactating cows 4 years old; (4) faecal culture on all lactating cows; and (5) milk-ELISA plus faecal culture in series on all lactating cows. The five testing strategies were evaluated...
Nielsen, Torben Dahl; Kudahl, Anne Braad; Østergaard, S.
Salmonella Dublin affects production and animal health in cattle herds. The objective of this study was to quantify the gross margin (GM) losses following introduction and spread of S. Dublin within dairy herds. The GM losses were estimated using an age-structured stochastic, mechanistic...... 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...... heifer were estimated through 1000 simulation iterations for 12 scenarios. These 12 scenarios were combinations of three herd sizes (85, 200 and 400 cows) and four management levels (very good, good, poor and very poor). Input parameters for effects of S. Dublin on production and animal health were based...
reduce the prevalence of clinical and sub-clinical mastitis in dairy herds.
McAloon, Conor G; Whyte, Paul; More, Simon J; O'Grady, Luke; Doherty, Michael L
Paratuberculosis is a challenging disease to control at farm level, in part due to the poor sensitivity of diagnostic tests and a prolonged incubation period. Simulation studies have highlighted on-farm management to be the most important factor in preventing on-farm spread. A risk assessment (RA) and management plan (MP) approach (collectively, RAMP) has been adopted around the world as the most appropriate method of controlling disease in infected farms. However, there are problems with RAMP that remain to be resolved. The RA relies heavily on farmer recollection and estimation resulting in subjectivity and substantial inter-observer variability. MPs consist of a series of qualitative, farm specific recommendations showing how management can be improved. However, MP assessment is generally conducted informally, and progress is monitored through 'end-point' diagnostic testing of adult animals and repeated risk assessments. Hazard analysis and critical control point (HACCP) has been developed as a proactive alternative to end-point testing. We hypothesise that farm-based HACCP systems may be a useful alternative to RAMP on farms where more intensive monitoring and evaluation of controls for paratuberculosis is required. Therefore, the objective of this methodological study was to develop a HACCP-based system for paratuberculosis control. Critical control points (CCPs) relating to peri-parturient area management, calving, new-born calf management and colostrum management were identified as areas where additional control could be exerted above existing methods. Novel monitoring systems were developed for each CCP, along with targets and corrective actions. This system is intended for use in high prevalence herds, or farms where more robust monitoring of key control points may be beneficial. It is currently being trialled on infected commercial dairy herds in Ireland. Copyright © 2015 Elsevier B.V. All rights reserved.
Abebe, Rahmeto; Hatiya, Hagere; Abera, Mesele; Megersa, Bekele; Asmare, Kassahun
Mastitis is a disease of major economic importance in dairy industry worldwide. It is of particular concern in developing countries like Ethiopia, where milk and milk products are scarce. The objectives of the study were to estimate the prevalence of mastitis, identify the cow-and herd-level potential risk factors and isolate Staphylococcus aureus, one of etiological agents for contagious mastitis, from cows positive for mastitis. A total of 529 lactating cows selected randomly from 95 herds were screened by California mastitis test (CMT) for sub-clinical mastitis. Also 172 milk samples collected from CMT positive cows were cultured for isolation of S. aureus. Based on CMT result and clinical examination, the prevalence of mastitis at herd-level was 74.7% (95% CI: 64.5, 82.8). The corresponding cow-level prevalence was 62.6% (95% CI: 58.3, 66.7), of which 59.2 and 3.4% were sub-clinical and clinical mastitis cases, respectively. S. aureus was isolated from 51.2% of the milk samples cultured and 73.2% of the herds affected with mastitis. In the multivariable logistic regression model, the herd-level factors significantly associated (p mastitis were herd size, bedding material, and milking mastitic cows last, while at cow-level, breed, parity, stage of lactation, udder and leg hygiene, and teat end shape were noted to have a significant effect on mastitis occurrence. The very high prevalence of mastitis, more importantly the sub-clinical one, in the herds examined revealed the huge potential economic loss the sector suffers. Perhaps this was attributed to lack of implementation of the routine mastitis prevention and control practices by all of the herd owners. The findings of this study warrants the need for strategic approach including dairy extension that focus on enhancing dairy farmers' awareness and practice of hygienic milking, regular screening for sub-clinical mastitis, dry cow therapy and culling of chronically infected cows.
Frey, C F; Eicher, R; Raue, K; Strube, C; Bodmer, M; Hentrich, B; Gottstein, B; Marreros, N
Infections with helminth parasites can negatively affect performance of dairy cows. Knowledge on infection intensity, spatial distributions and risk factors are key to develop targeted treatment strategies. Canada and most EU countries have conducted large investigations, but respective data for Switzerland were missing. We now performed a bulk tank milk serosurvey for Ostertagia ostertagi, Fasciola hepatica, and Dictyocaulus viviparus on a total of 1036 voluntarily participating dairy herds that were sampled at confinement periods, i.e. in winter 2014/15 or 2015/16, respectively. All samples were analyzed with commercial ELISAs for antibodies (AB) against O. ostertagi and F. hepatica, and those of the first sampling period additionally with an in-house ELISA for AB against D. viviparus. Testing for the latter parasite was not done in the second year of the study, as the sampling period might have missed infections due to the short lived nature of specific antibodies. The possible influence of geographic, climatic, and farm management variables on AB levels were assessed for each parasite using scanning cluster and multiple regression analysis. Overall seroprevalence for O. ostertagi was 95.5% (95% C.I.: 94.0-96.6), with a mean optical density ratio (ODR) of 0.83, for F. hepatica 41.3% (95% C.I.: 38.3-44.4), and for D. viviparus 2.9% (95% C.I.: 1.6-4.7). There were no significant differences between the two sampling periods. For all parasites, significant geographic clusters of higher AB levels could be established. Furthermore, AB levels against all three parasites were positively correlated with each other, indicating either cross-reactions or co-infections. For O. ostertagi, herd size and percentage of pasture in the ration were positively correlated with AB levels. For F. hepatica, altitude above sea level (a.s.l.) positively, and milk production per cow and year was negatively correlated with AB levels. This work provides baseline data for further
Belage, E; Dufour, S; Shock, D A; Jones-Bitton, A; Kelton, D F
Milking management practices that affect udder health have been widely studied, leading to a variety of evidence-based recommendations. Lack of adoption or inconsistency in milking practices can interfere with efforts to prevent mastitis in the herd. The study objective was to assess the variation in adoption and application consistency of important milk harvest practices between and within farms over time. During the summer of 2013, 50 herds in southern Ontario were visited twice within a month, at milking time, and a single person observed and time-recorded premilking preparation procedures. A generalized mixed model was used to partition the variance for predisinfectant contact time and preparation lag time (time between the first contact with the teats and cluster attachment), and determine the proportion of variation attributable to farms, milkers, visits, and characteristics of a cow milking. Using logistic regression, models were built to assess factors affecting adequate contact time and adequate preparation lag time, respectively. Farm, the person(s) milking, and visit number were used as random effects in both instances. In both models, farm-to-farm differences and variations between cows during a specific milking accounted for the largest part of the variability seen in both contact time (47 and 44%, respectively) and preparation lag time (40 and 36%, respectively). For both outcomes, milkers were consistent in their routines over the 2 visits (only 9 and 3.1% of total variance for contact and preparation lag time, respectively). Parlors were more likely to meet the recommended contact time than tie-stalls; increased number of milkers at milking time and having contact times under 30 s had negative effects on meeting recommended preparation lag time. The majority of farms in the study complied with the recommendations for adequate milking practices; however, most did not follow a consistent timed protocol. There are several potential sources of variation
Full Text Available Abstract Epidemiological models enable to better understand the dynamics of infectious diseases and to assess ex-ante control strategies. For Mycobacterium avium subsp. paratuberculosis (Map, possible transmission routes have been described, but Map spread in a herd and the relative importance of the routes are currently insufficiently understood to prioritize control measures. We aim to predict early after Map introduction in a dairy cattle herd whether infection is likely to fade out or persist, when no control measures are implemented, using a modelling approach. Both vertical transmission and horizontal transmission via the ingestion of colostrum, milk, or faeces present in the contaminated environment were modelled. Calf-to-calf indirect transmission was possible. Six health states were represented: susceptible, transiently infectious, latently infected, subclinically infected, clinically affected, and resistant. The model was partially validated by comparing the simulated prevalence with field data. Housing facilities and contacts between animals were specifically considered for calves and heifers. After the introduction of one infected animal in a naive herd, fadeout occurred in 66% of the runs. When Map persisted, the prevalence of infected animals increased to 88% in 25 years. The two main transmission routes were via the farm's environment and in utero transmission. Calf-to-calf transmission was minor. Fadeout versus Map persistence could be differentiated with the number of clinically affected animals, which was rarely above one when fadeout occurred. Therefore, early detection of affected animals is crucial in preventing Map persistence in dairy herds.
Emanuel S. Swai
Full Text Available A cross-sectional study was conducted to determine prevalence and risk factors of cryptosporidiosis in bovine from two contrasting production system in and around Tanga municipality between May 2003 and January 2004. The study populations comprised 117 calves aged ≤3 months, randomly selected from 44 smallholders dairy and traditional managed herds, respectively. Individual calf and herd-level information was collected using a structured questionnaire and feacal samples were screened for Cryptosporidium spp oocysts using the modified Ziehl-Neelsen method. Overall, 35% of the calves in the study were shedding Cryptosporidium spp oocysts, with at least one positive calf detected in 54.5% of herds. Independent risk factors for cryptosporidiosis were: age ≥1 to ≤2 months and level of cleanness of calf house floor categorized as dirty (<.05. Similarly an increases risk of Cryptosporidium spp infection was found in calves from smallholder dairy units compared to traditional herds (<.05. The finding highlights that Cryptosporidium spp is prevalent among calves in the area under study. The high prevalence of cryptosporidiosis detected in this study suggests that it may have a significant impact on livestock industry and that the close interaction between cattle and human may play a role in zoonotic transmission to humans.
Olivier B. Kashongwe
Full Text Available On-farm hygienic practices are important in assuring quality and safety of milk for consumers and for reducing losses at production and at post-harvest. This study investigated the relationship between milking practices, mastitis as well as milk somatic cell counts (SCC and the effects of high SCC on milk production and post-harvest losses (PHL in smallholder dairy (n = 64 and pastoral camel (n = 15 herds in Kenya. The collected data included milking practices, mastitis test on udder quarters (n = 1236 and collection of milk samples for laboratory analyses: SCC, detection of Staphylococcus aureus and Streptococcus species. Production losses were computed as a proportion of cows and herds with SCC (>200,000 cells/mL and PHL as quantity of milk exceeding 4 × 105 cells/mL. Practices associated with production herds included hands, udder washing and drying, and milk let down stimulation with calves suckling or manually (p < 0.001. Udder drying was only applied in peri-urban herds (100%. Herd level prevalence of mastitis was lower in smallholder than in pastoral herds (60.7% vs 93.3%. Mastitis positive samples had higher prevalence of S.aureus than of Streptococcus species in both smallholder (57.9% vs 23.7% and pastoral (41.6% vs 36.5% herds. Moreover, SCC was significantly affected by presence of mastitis and S.aureus (p < 0.001. Milk PHL from high SCC was higher in smallholder rural herds (27% compared to peri-urban (7% and in pastoral peri-urban (81% compared to rangelands (76%. Milking practices may have contributed to maintain mastitis pathogens in herds. This has led to substantial pre and postharvest milk losses in smallholder and pastoral herds. Therefore teat dipping, dry cow period and herd level mastitis treatment may complement current practices for lower SCC and milk PHL.
Amaury Apolonio de Oliveira
Full Text Available ABSTRACT. Oliveira A.A., Seixas L., Azevedo H.C., Teixeira K.M., McManus C. & de Melo C.B. Evaluation of the use of good practices in dairy cattle herds. [Avaliação da utilização de boas práticas em rebanhos bovinos leiteiros.] Revista Brasileira de Medicina Veterinária, 37(1:73-77, 2015. Universidade de Brasília (UnB/FAV/DINO, Campus Universitário Darcy Ribeiro, ICC Sul, Asa Norte, Brasília, DF 70910-900, Brazil. E-mail: email@example.com The aim of this work was to evaluate and monitor milk quality using good practices (GP for milking procedures, and thereby improve sanitary conditions and milk safety during milking process, storage and transportation. For each milk sample, the somatic cell count (SCC, total bacteria count (TBC and milk components were determined. Initially, 236 dairy farms were monitored in the Tabuleiros Costeiros, Agreste and Semi-arid regions of the State of Sergipe, in the northeast of Brazil. Twenty family farms were then selected for implementation of GP procedures. It was verified that, before the use of GP, only 12.94% of the farms produced milk that had hygienic quality consistent with the legislation in Brazil. The use of GP procedures during milking and subsequent cooling raised this rate to 32.53%. The results demonstrated the importance of a hygiene program during milking, storage and transportation of milk.
Stiglbauer, K E; Cicconi-Hogan, K M; Richert, R; Schukken, Y H; Ruegg, P L; Gamroth, M
The objective of this study was to evaluate management characteristics on organic and similarly sized conventional dairy farms located in New York, Wisconsin, and Oregon. Data from 192 organic farms (ORG), 64 conventional nongrazing farms (CON-NG), and 36 conventional grazing farms (CON-GR) were collected during farm visits and were size-matched and analyzed. The average lactation number of animals on ORG and CON-GR farms was 2.6 lactations, which was greater than that on CON-NG farms (2.3 lactations). A greater percentage of first-lactation heifers were found on conventional farms than on ORG farms. Facilities used by adult animals, including housing and milking facilities, did not differ among the grazing systems. Cattle on conventional farms were fed approximately twice as much grain as cattle on ORG farms and had greater milk production. Little difference was found for the average reported somatic cell count and standard plate count, suggesting that milk quality is not dependent on grazing system. Milking procedures were similar across all 3 grazing systems, indicating that an industry standard now exists for milking and that milk quality problems will need to be addressed with other management problems in mind. Although some disease prevention measures were commonly utilized on ORG farms, such as keeping a closed herd and having a written record of treatments administered to the animals, the use of outside support and vaccinations were found to be less prevalent on organic farms than on conventional farms. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Castro, A.; Pereira, J.M.; Amiama, C.; Bueno, J.
Over the last few years, the adoption of automatic milking systems (AMS) has experienced significant increase. However, hardly any studies have been conducted to investigate the distribution of mastitis pathogens in dairy herds with AMS. Because quick mastitis detection in AMS is very important, the primary objective of this study was to determine operational reliability and sensibility of mastitis detection systems from AMS. Additionally, the frequency of pathogen-specific was determined. For this purpose, 228 cows from ten farms in Galicia (NW Spain) using this system were investigated. The California Mastitis Test (CMT) was considered the gold-standard test for mastitis diagnosis and milk samples were analysed from CMT-positive cows for the bacterial examination. Mean farm prevalence of clinical mastitis was 9% and of 912 milk quarters examined, 23% were positive to the AMS mastitis detection system and 35% were positive to the CMT. The majority of CMT-positive samples had a score of 1 or 2 on a 1 (lowest mastitis severity) to 4 (highest mastitis severity) scale. The average sensitivity and specificity of the AMS mastitis detection system were 58.2% and 94.0% respectively being similar to other previous studies, what could suggest limitations for getting higher values of reliability and sensibility in the current AMSs. The most frequently isolated pathogens were Streptococcus dysgalactiae (8.8%), followed by Streptococcus uberis (8.3%) and Staphylococcus aureus (3.3%). The relatively high prevalence of these pathogens indicates suboptimal cleaning and disinfection of teat dipping cups, brushes and milk liners in dairy farms with AMS in the present study. (Author)
Stockmarr, Anders; Bødker, Rene; Nielsen, L. R.
the herds being “likely infected” according to the existing classification system in the present quarter. The alarm herd concept can be used as a new early warning element in the existing surveillance program. Additionally, to improve accuracy of herd classification, the alarm herd concept could...... “likely free of infection” to “likely infected” in the following quarter of the year, thus warning the farmer 3mo earlier than the present system. The alarm herd concept was defined through aberrations from a stable development over time of antibody levels. For suitable parameter choices, alarm herd...
Burow, Elke; Thomsen, Peter Thorup; Sørensen, Jan Tind
to a zero-grazing herd having automatic milking system. In traditional milking system, mortality was reduced to 75% in grazing compared to zero-grazing herds. Within the grazing herds, the risk of mortality decreased with increasing number of hours on pasture during the season. Free access between barn...... a questionnaire survey of grazing procedures on these herds in 2008. In all, 131 of the herds were identified as summer grazing and 260 as zero-grazing herds. The mortality was affected by an interaction of summer grazing and milking system. The risk of a cow dying was reduced to 46% in a grazing compared...
Adna Crisléia Rodrigues Monção de Lima
Full Text Available The technical regulation that is currently in effect for the production, identity and quality of the milk in Brazil is the Normative Instruction 62 (NI 62, published on December 29th 2011. Since January 1st, 2012 this legislation sets for pasteurized milk type A the Somatic Cell Count (SCC limit of 4.8 x 105 cel. mL-1until June, 30th, 2014, decreasing the limit in the following years til it reaches 3.6 x 105 cel. mL-1from July, first 2016. From now, the limit of SCC for refrigerated raw milk in the Southeast region is 6.0 x 105 cel. mL-1, decreasing in the following years til it reaches 5.0 x 105 cel. mL-1from July, 1st 2014. The control of the amount of SCC in the milk is important for monitoring the milk quality and sanity from a dairy herd. The objective of the present study was to verify if nine dairy farms in the state of São Paulo attend the NI 62 to the limit of SCC. Milk samples were collected directly from the milk glass recording jar in sterile flasks containing bromothymol as conservative. It was evaluated in each herd 15 cows randomly selected. From the results, averages were made from all farms. The determination of SCC was performed by flow cytometry in clinical milk ESALQ-USP, Piracicaba-SP. The herds had different results. One of the properties (A produces pasteurized milk type A and the SCC is under the limit imposed by the NI 62. The others produce refrigerated raw milk. The properties B, C and I are in the limit established by NI 62. The properties D, E, F, G and H are out of the limits stablished by the NI 62 (6.0 x 105 cel. mL-1. The most worrisome findings derive from the properties E and F, which are the result of mismanagement and poor conditions of milking. It is known that high SCC is related to the presence of subclinical mastitis, which represents significant losses in milk production, compromises animal welfare and offers potential risks to consumer health. The owners of properties E and F should be
Full Text Available Abstract Background Research has been scarce when it comes to the motivational and behavioral sides of farmers' expectations related to dairy herd health management programs. The objectives of this study were to explore farmers' expectations related to participation in a health management program by: 1 identifying important ambitions, goals and subjective well-being among farmers, 2 submitting those data to a quantitative analysis thereby characterizing perspective(s of value added by health management programs among farmers; and 3 to characterize perceptions of farmers' goals among veterinarians. Methods The subject was initially explored by means of literature, interviews and discussions with farmers, herd health management consultants and researchers to provide an understanding (a concourse of the research entity. The concourse was then broken down into 46 statements. Sixteen Danish dairy farmers and 18 veterinarians associated with one large nationwide veterinary practice were asked to rank the 46 statements that defined the concourse. Next, a principal component analysis was applied to identify correlated statements and thus families of perspectives between respondents. Q-methodology was utilized to represent each of the statements by one row and each respondent by one column in the matrix. A subset of the farmers participated in a series of semi-structured interviews to face validate the concourse and to discuss subjects like animal welfare, veterinarians' competences as experienced by the farmers and time constraints in the farmers' everyday life. Results Farmers' views could be described by four families of perspectives: Teamwork, Animal welfare, Knowledge dissemination, and Production. Veterinarians believed that farmers' primary focus was on production and profit, however, farmers' valued teamwork and animal welfare more. Conclusion The veterinarians in this study appear to focus too much on financial performance and increased
Piessens, V; Van Coillie, E; Verbist, B; Supré, K; Braem, G; Van Nuffel, A; De Vuyst, L; Heyndrickx, M; De Vliegher, S
In many parts of the world, coagulase-negative staphylococci (CNS) are the predominant pathogens causing intramammary infections (IMI) in dairy cows. The cows' environment is thought to be a possible source for CNS mastitis and this was investigated in the present paper. A longitudinal field study was carried out in 6 well-managed dairy herds to determine the distribution and epidemiology of various CNS species isolated from milk, causing IMI and living freely in the cows' environment, respectively. In each herd, quarter milk samples from a cohort of 10 lactating cows and environmental samples from stall air, slatted floor, sawdust from cubicles, and sawdust stock were collected monthly (n=13). Isolates from quarter milk samples (n=134) and the environment (n=637) were identified to species level using amplified fragment length polymorphism (AFLP) genotyping. Staphylococcus chromogenes, S. haemolyticus, S. epidermidis, and S. simulans accounted for 81.3% of all CNS milk isolates. Quarters were considered infected with CNS (positive IMI status) only when 2 out of 3 consecutive milk samples yielded the same CNS AFLP type. The species causing IMI were S. chromogenes (n=35 samples with positive IMI status), S. haemolyticus (n=29), S. simulans (n=14), and S. epidermidis (n=6). The observed persistent IMI cases (n=17) had a mean duration of 149.4 d (range 63.0 to 329.8 d). The CNS species predominating in the environment were S. equorum, S. sciuri, S. haemolyticus, and S. fleurettii. Herd-to-herd differences in distribution of CNS species were observed in both milk and the environment, suggesting that herd-level factors are involved in the establishment of particular species in a dairy herd. Primary reservoirs of the species causing IMI varied. Staphylococcus chromogenes and S. epidermidis were rarely found in the environment, indicating that other reservoirs were more important in their epidemiology. For S. haemolyticus and S. simulans, the environment was found as a
Part 1 of the study described the development of a Hazard Analysis and Critical Control Point (HACCP) based programme and accompanying handbook for the control of mastitis. This paper describes the implementation and evaluation of customised HACCP-based programmes, which were developed from the handbook and assessed on six Irish dairy farms. Both quantitative and qualitative (action research) research methodologies were used to measure the success of implementation and efficacy of control of sub-clinical mastitis as measured by Somatic Cell Counts (SCC) and the degree of compliance by farmers in adopting and maintaining recommendations throughout the course of the study period. No overall differences in SCC before and during the implementation of the study were found when all six farms were considered together. Three of the six study farms experienced a significant decrease in herd milk recorded SCC during the implementation of the control programme. An essential part of the study was achieving initial agreement on recommendations as well as ongoing monitoring of compliance during the study. This pilot study shows that HACCP can be implemented on farms as a means of working towards the control of mastitis and that farmer attitude, and understanding of mastitis are crucial in terms of motivation irrespective of practical approaches used to manage mastitis. PMID:21777494
Sosa, Camila; Tirante, Liliana; Chaves, Javier; Pol, Martín; Ambrogi, Arnaldo; Giraudo, José Angel; Tamiozzo, Pablo
Several species of Mycoplasma and Ureaplasma diversum can cause diseases in dairy cattle, which can be associated or not with clinical manifestations. In our country, the presence of Mycoplasma bovis, Mycoplasma californicum and Mycoplasma canadense has been detected, being the only mycoplasma species identified so far. The objective of this study was to identify other species of the Mycoplasmataceae family. Thirty-five Mycoplasma spp.-like isolates obtained from different samples from cattle, with or without clinical symptoms, from eight herds located in the provinces of Santa Fe, Cordoba, Buenos Aires and San Luis were utilized in the present study. Through the use of species-specific polymerase chain reactions (PCR) Mycoplasma bovigenitalium, Mycoplasma alkalescens, Mycoplasma bovirhinis and U. diversum were identified and through amplification and further sequencing of the 16-23S rRNA intergenic spacer regions, Mycoplasma arginine and M. californicum were identified. The identification of these species represents an important advance in knowledge in order to include these pathogens in the differential diagnosis of certain clinical and pathological entities of cattle from Argentina. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
Full Text Available Abstract Part 1 of the study described the development of a Hazard Analysis and Critical Control Point (HACCP based programme and accompanying handbook for the control of mastitis. This paper describes the implementation and evaluation of customised HACCP-based programmes, which were developed from the handbook and assessed on six Irish dairy farms. Both quantitative and qualitative (action research research methodologies were used to measure the success of implementation and efficacy of control of sub-clinical mastitis as measured by Somatic Cell Counts (SCC and the degree of compliance by farmers in adopting and maintaining recommendations throughout the course of the study period. No overall differences in SCC before and during the implementation of the study were found when all six farms were considered together. Three of the six study farms experienced a significant decrease in herd milk recorded SCC during the implementation of the control programme. An essential part of the study was achieving initial agreement on recommendations as well as ongoing monitoring of compliance during the study. This pilot study shows that HACCP can be implemented on farms as a means of working towards the control of mastitis and that farmer attitude, and understanding of mastitis are crucial in terms of motivation irrespective of practical approaches used to manage mastitis.
Nobrega, Diego B; Naushad, Sohail; Naqvi, S Ali; Condas, Larissa A Z; Saini, Vineet; Kastelic, John P; Luby, Christopher; De Buck, Jeroen; Barkema, Herman W
Emergence and spread of antimicrobial resistance is a major concern for the dairy industry worldwide. Objectives were to determine: (1) phenotypic and genotypic prevalence of drug-specific resistance for 25 species of non-aureus staphylococci, and (2) associations between presence of resistance determinants and antimicrobial resistance. Broth micro-dilution was used to determine resistance profiles for 1,702 isolates from 89 dairy herds. Additionally, 405 isolates were sequenced to screen for resistance determinants. Antimicrobial resistance was clearly species-dependent. Resistance to quinupristin/dalfopristin was common in Staphylococcus gallinarum (prevalence of 98%), whereas S. cohnii and S. arlettae were frequently resistant to erythromycin (prevalence of 63 and 100%, respectively). Prevalence of resistance was 10% against β-lactams and tetracyclines. In contrast, resistance to antimicrobials critically important for human medicine, namely vancomycin, fluoroquinolones, linezolid and daptomycin, was uncommon (staphylococci from dairy cattle. These results will be important for evaluating effects of interventions in antimicrobial use in Canadian dairy herds.
O' Doherty, E; Berry, D P; O' Grady, L; Sayers, R
A survey of management practices in 309 Irish dairy herds was used to identify risk factors for the presence of antibodies to Salmonella, Neospora caninum and Leptospira interrogans serovar hardjo in extensively managed unvaccinated dairy herds. A previous study documented a herd-level seroprevalence in bulk milk of 49%, 19% and 86% for Salmonella, Neospora caninum and leptospira interrogans serovar hardjo, respectively in the unvaccinated proportion of these 309 herds in 2009. Association analyses in the present study were carried out using multiple logistic regression models. Herds where cattle were purchased or introduced had a greater likelihood of being positive to leptospira interrogans serovar hardjo (PNeospora caninum (PNeospora caninum possibly due to limited access of dogs to infected materials including afterbirths. The information from this study will assist in the design of suitable control programmes for the diseases under investigation in pasture-based livestock systems.
Kessels, J A; Cha, E; Johnson, S K; Welcome, F L; Kristensen, A R; Gröhn, Y T
This study used an existing dynamic optimization model to compare costs of common treatment protocols and J5 vaccination for clinical mastitis in US dairy herds. Clinical mastitis is an infection of the mammary gland causing major economic losses in dairy herds due to reduced milk production, reduced conception, and increased risk of mortality and culling for infected cows. Treatment protocols were developed to reflect common practices in dairy herds. These included targeted therapy following pathogen identification, and therapy without pathogen identification using a broad-spectrum antimicrobial or treating with the cheapest treatment option. The cost-benefit of J5 vaccination was also estimated. Effects of treatment were accounted for as changes in treatment costs, milk loss due to mastitis, milk discarded due to treatment, and mortality. Following ineffective treatments, secondary decisions included extending the current treatment, alternative treatment, discontinuing treatment, and pathogen identification followed by recommended treatment. Average net returns for treatment protocols and vaccination were generated using an existing dynamic programming model. This model incorporates cow and pathogen characteristics to optimize management decisions to treat, inseminate, or cull cows. Of the treatment protocols where 100% of cows received recommended treatment, pathogen-specific identification followed by recommended therapy yielded the highest average net returns per cow per year. Out of all treatment scenarios, the highest net returns were achieved with selecting the cheapest treatment option and discontinuing treatment, or alternate treatment with a similar spectrum therapy; however, this may not account for the full consequences of giving nonrecommended therapies to cows with clinical mastitis. Vaccination increased average net returns in all scenarios. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
M. A. Lopes
Full Text Available he objective of this study was to identify and quantify the most representative factor affecting the economic impact of mastitis in dairy cattle herds in order to establish those that should receive greater attention from farmers and technicians to reduce the economic impact of this important disease. A simulation study was conducted with the CU$TO MASTITE program, considering 324 different herds and using combinations of the following factors: somatic cell count (250,000; 500,000; 750,000 and 1,000,000 somatic cells/mL milk; production scale (50; 100 and 150 lactating cows; productivity per animal (10; 20 and 30 L/cow/day; average annual incidence of clinical mastitis (1%; 7% and 15%, and involuntary culling rate due to mastitis (2%; 4% and 6%. Preventive measures included expenses with monitoring [culture and antibiogram, bulk tank somatic cell count (BTSCC, and individual somatic cell counts], pre- and post-dipping, vaccination, treatment of dry cows, and maintenance of the milking machine. Only treatments of clinical cases were considered as curative measures. The impact of mastitis was estimated as total losses plus expenses with prevention and treatment of clinical cases. The mean incidence of clinical mastitis (MIM and BTSCC were significant (P<0.05 in five of the seven models analyzed [economic impact per lactating cow (ILC, economic impact per liter of milk (ILM, economic impact of curative treatment per liter of milk (CTM, economic impact of milk disposal/liter of sold milk (IMD, and economic impact of reduction in production per liter of milk (IRM]. However, the standardized coefficient for MIM was higher in three indicators (ILC, IMD and CTM, a fact rendering this factor more representative when compared to BTSCC, which also had five significant indicators. Comparison of the medians of curative treatments and preventive measures per lactating cow revealed an excellent cost/benefit ratio. These findings demonstrate that both
Rola, Jolanta G; Larska, Magdalena; Grzeszuk, Monika; Bocian, Lukasz; Kuta, Aleksandra; Polak, Miroslaw P; Rola, Jerzy
The aim of the study was to examine the effect of bovine viral diarrhoea virus (BVDV) infection on bulk tank milk somatic cell counts (BMSCC). Twenty nine dairy farms supplying milk to a dairy in Eastern Poland were recruited for the study. Bulk milk ELISA and RT-PCR were used to determine the BVDV infection status and the presence of PI animals in the farms. The BMSCC mean values for the BVDV seronegative (218.7 × 10(3)cells/ml; SD: 89.8) and seropositive (214.9 × 10(3)cells/ml; SD: 74.0) herds did not differ significantly. To assess the relationship between BVDV infection and BMSCC a multilevel mixed-effects linear model was used. No statistically significant effect of BVDV infection on BMSCC was found. The mean values of BMSCC for the herds with PI individuals measured before (230.1 × 10(3)cells/ml, SD: 64.9) and after (223.3 × 10(3)cells/ml, SD: 62.4) the PI removal were not statistically different. An increase in herd size was associated with a significant decrease in BMSCC. An increase in BMSCC was observed during summer (from May to September) compared to during winter (from October to April). Copyright © 2014 Elsevier B.V. All rights reserved.
Giuliodori, M J; Magnasco, R P; Becu-Villalobos, D; Lacau-Mengido, I M; Risco, C A; de la Sota, R L
The objectives of this study were to assess the clinical and metabolic risk factors for clinical endometritis, the likelihood for having a normal vaginal discharge during postpartum, and the effects of endometritis on milk yield, reproductive efficiency, and metabolic status in Holstein cows. The study was conducted in a commercial dairy herd (Cordoba, Argentina) where 303 Holstein cows were enrolled. Cows were body condition scored (1 to 5) and tail bled on -14, 7, 21, 31, 41, and 50 d relative to parturition. Cows having a vaginal discharge with presence of pus between 21 and 41 d postpartum (dpp) were diagnosed as having clinical endometritis. Plasma blood samples were analyzed for nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), and blood urea nitrogen using commercial kits and insulin-like growth factor 1, insulin, and leptin by RIA. Data were analyzed with PROC MIXED, PROC GENMOD, and PROC PHREG of SAS (SAS Institute Inc., Cary, NC). Abnormal calving and puerperal metritis increased the risk for endometritis [adjusted odds ratio (AOR)=2.21 for both]. High prepartum NEFA and high postpartum BHBA increased the risk for endometritis (AOR=1.003 and 1.001, respectively), whereas high prepartum blood urea nitrogen reduced it (AOR=0.853). Cut-offs of 456.6 μM NEFA and 402.5 μM BHBA had sensitivities of 0.69 and 0.58, and specificities of 0.88 and 0.86, respectively. The likelihood for having normal vaginal discharge increased with time (∼1% × dpp) and with normal calving. Cows with endometritis had higher milk yield than normal herdmates (27.8±0.9 vs. 25.7±0.4 kg/d), lower risk for pregnancy by 100 dpp (AOR=0.10), higher nonpregnancy risk by 200 dpp (AOR=2.87), and higher risk for culling than normal cows (AOR=2.28). Cows with endometritis had a lower hazard rate (0.44) for pregnancy and had approximately 70 d longer calving-to-conception intervals. Finally, endometritis had no effect on metabolic hormones. In conclusion, the risk for clinical
Ito, K; Chapinal, N; Weary, D M; von Keyserlingk, M A G
Our objective was to investigate the associations between herd-level factors and lying behavior of high-producing dairy cows housed in freestall barns. Lying behavior of approximately 40 focal cows in one high-producing pen was monitored on each of 40 farms in the northeastern United States (NE) and 39 farms in California (CA). All cows within the pen were gait scored using a 1-to-5 scale to calculate the prevalence of clinical lameness (score ≥3) and severe lameness (score ≥4). Facility and management measures, including stall design, bedding, and flooring type within the pen, were collected. Herd-level factors associated with daily lying time, standard deviation (SD) of daily lying time, frequency of lying bouts, and lying bout duration at the univariate level were submitted to multivariable general linear models. In the NE, daily lying time increased with the use of deep bedding (estimate = 0.80±0.31h/d) and as average days in milk (DIM) of the focal cows increased (estimate = 0.08±0.04h/d for a 10-d increase in DIM). The SD of daily lying time decreased as stall stocking density increased (estimate = -0.08±0.03h/d for a 10% increase), and increased with the presence of rubber flooring in the pen (estimate = 0.16±0.08h/d) and percentage of stalls with fecal contamination (estimate = 0.04±0.01h/d for a 10% increase). Frequency of lying bouts decreased (estimate = -1.90±0.63 bouts/d) and average bout duration increased (estimate = 15.44±3.02 min) with the use of deep bedding. In CA, where all farms used deep bedding, daily lying time increased as average DIM of the focal cows increased (estimate = 0.08±0.03h/d for a 10-d increase). The SD of daily lying time decreased when feed was delivered more than once per day (estimate = -0.24±0.08h/d). The percentage of lame cows was correlated with the percentage of stalls with fecal contamination (r=0.45), which in turn was associated with fewer (estimate = -0.25±0.06 bouts/d) and longer lying bouts (estimate
Tikofsky, L L; Zadoks, R N
Group G streptococci in animals usually belong to the species Streptococcus canis and are most commonly found in dogs and cats. Occasionally, Strep. canis is detected in milk from dairy cows. An outbreak of Strep. canis mastitis in a dairy herd is described. Based on results from bacterial culture and ribotyping, a cat with chronic sinusitis was the most likely source of the outbreak. Subsequent cow-to-cow transmission of Strep. canis was facilitated by poor udder health management, including use of a common udder cloth and failure to use postmilking teat disinfection. Infected cows had macroscopically normal udders and milk, but significantly higher somatic cell counts than Strep. canis-negative herd mates. The outbreak was controlled through antibiotic treatment of lactating cows, early dry-off with dry cow therapy, culling of infected animals, and implementation of standard mastitis prevention measures. Cure was significantly more likely in dry-treated cows (87.5%) and cows treated during lactation (67%) than in untreated cows (9%). Whereas mastitis due to group G streptococci or Strep. canis in dairy cows is usually limited to sporadic cases of environmental (canine or feline) origin, this case study shows that crossing of the host species barrier by Strep. canis may result in an outbreak of mastitis if management conditions are conducive to contagious transmission. In such a situation, measures that are successful in control of Strep. agalactiae can also be used to control Strep. canis mastitis.
Sørensen, J.T.; Enevoldsen, Carsten; Houe, H.
A dynamic, stochastic model simulating the technical and economic consequences of bovine virus diarrhoea virus (BVDV) infections for a dairy cattle herd for use on a personal computer was developed. The production and state changes of the herd were simulated by state changes of the individual cows...... variables describing biologic and management variables including 21 decision variables describing the effect of BVDV infection on the production of the individual animal. Two markedly different scenarios were simulated to demonstrate the behaviour of the developed model and the potentials of the applied...... and heifers. All discrete events at the cow level were triggered stochastically. Each cow and heifer was characterized by state variables such as stage of lactation, parity, oestrous status, decision for culling, milk production potential, and immune status for BVDV. The model was controlled by 170 decision...
Hiitiö, Heidi; Vakkamäki, Johanna; Simojoki, Heli; Autio, Tiina; Junnila, Jouni; Pelkonen, Sinikka; Pyörälä, Satu
The dairy industry has undergone substantial structural changes as intensive farming has developed during recent decades. Mastitis continues to be the most common production disease of dairy cows. Nationwide surveys of mastitis prevalence are useful in monitoring udder health of dairy herds and to study the impact of structural changes on the dairy industry. This survey on bovine subclinical mastitis was the first based on cow composite milk somatic cell count (SCC) data from the Finnish national health monitoring and milk recording database. A cow with composite milk SCC ≥200,000 cells/ml in at least one of the four test milkings during the year was considered to have subclinical mastitis and a cow with composite milk SCC ≥200,000 cells/ml in three or in all four test milkings during the year to have chronic subclinical mastitis. The aim of the study was to determine the prevalence of subclinical mastitis and chronic subclinical mastitis in Finland in 1991, 2001 and 2010 and to investigate cow and herd factors associated with elevated SCC. Prevalence of subclinical mastitis in Finland decreased over recent decades from 22.3% (1991) and 20.1% (2001) to 19.0% (2010). Prevalence of chronic subclinical mastitis was 20.4% in 1991, 15.5% in 2001 and 16.1% in 2010. The most significant cow and herd factors associated with subclinical mastitis or high milk SCC were increasing parity, Holstein breed, free-stalls with an automatic milking system and organic production. Milk SCC were highest from July to September. Main factors associated with chronic mastitis were increasing parity and Holstein breed. Prevalence of subclinical mastitis in Finland decreased over recent decades, the greatest change taking place during the first decade of the study. Prevalence of chronic subclinical mastitis significantly decreased from 1991. The most significant factors associated with both types of mastitis were increasing parity and Holstein breed, and for subclinical mastitis also
Full Text Available Abstract Background Quarter milk samples from cows with high risk of intramammary infection were examined to determine the prevalence of Staphylococcus aureus (SA and penicillin resistant SA (SAr in conventional and organic dairy herds and herds converting to organic farming in a combined longitudinal and cross-sectional study. Methods 20 conventional herds, 18 organic herds that converted before 1995, and 19 herds converting to organic farming in 1999 or 2000 were included in the study. Herds converting to organic farming were sampled three times one year apart; the other herds were sampled once. Risk of infection was estimated based on somatic cell count, milk production, breed, age and lactation stage. Results The high-risk cows represented about 49 % of the cows in the herds. The overall prevalence of SA and SAr among these cows was 29% (95% confidence interval: 24%–34% and 4% (95% confidence interval: 2%–5% respectively. The prevalence of penicillin resistance among SA infected cows was 12% (95% confidence interval: 6%–19% when calculated from the first herd visits. No statistically significant differences were observed in the prevalence of SAr or the proportion of isolates resistant to penicillin between herd groups. Conclusion The proportion of isolates resistant to penicillin was low compared to studies in other countries except Norway and Sweden. Based on the low prevalence of penicillin resistance of SA, penicillin should still be the first choice of antimicrobial agent for treatment of bovine intramammary infection in Denmark.
Hayer, S S; VanderWaal, K; Ranjan, R; Biswal, J K; Subramaniam, S; Mohapatra, J K; Sharma, G K; Rout, M; Dash, B B; Das, B; Prusty, B R; Sharma, A K; Stenfeldt, C; Perez, A; Delgado, A H; Sharma, M K; Rodriguez, L L; Pattnaik, B; Arzt, J
Foot-and-mouth disease (FMD) is an important transboundary disease with substantial economic impacts. Although between-herd transmission of the disease has been well studied, studies focusing on within-herd transmission using farm-level outbreak data are rare. The aim of this study was to estimate parameters associated with within-herd transmission, host physiological factors and FMD virus (FMDV) persistence using data collected from an outbreak that occurred at a large, organized dairy farm in India. Of 1,836 regularly vaccinated, adult dairy cattle, 222 had clinical signs of FMD over a 39-day period. Assuming homogenous mixing, a frequency-dependent compartmental model of disease transmission was built. The transmission coefficient and basic reproductive number were estimated to be between 16.2-18.4 and 67-88, respectively. Non-pregnant animals were more likely to manifest clinical signs of FMD as compared to pregnant cattle. Based on oropharyngeal fluid (probang) sampling and FMDV-specific RT-PCR, four of 36 longitudinally sampled animals (14%) were persistently infected carriers 10.5 months post-outbreak. There was no statistical difference between subclinical and clinically infected animals in the duration of the carrier state. However, prevalence of NSP-ELISA antibodies differed significantly between subclinical and clinically infected animals 12 months after the outbreak with 83% seroprevalence amongst clinically infected cattle compared to 69% of subclinical animals. This study further elucidates within-herd FMD transmission dynamics during the acute-phase and characterizes duration of FMDV persistence and seroprevalence of FMD under natural conditions in an endemic setting. © 2017 Blackwell Verlag GmbH.
Use of whole-genome sequencing and evaluation of the apparent sensitivity and specificity of antemortem tuberculosis tests in the investigation of an unusual outbreak of Mycobacterium bovis infection in a Michigan dairy herd.
Bruning-Fann, Colleen S; Robbe-Austerman, Suelee; Kaneene, John B; Thomsen, Bruce V; Tilden, John D; Ray, Jean S; Smith, Richard W; Fitzgerald, Scott D; Bolin, Steven R; O'Brien, Daniel J; Mullaney, Thomas P; Stuber, Tod P; Averill, James J; Marks, David
OBJECTIVE To describe use of whole-genome sequencing (WGS) and evaluate the apparent sensitivity and specificity of antemortem tuberculosis tests during investigation of an unusual outbreak of Mycobacterium bovis infection in a Michigan dairy herd. DESIGN Bovine tuberculosis (bTB) outbreak investigation. ANIMALS Cattle, cats, dog, and wildlife. PROCEDURES All cattle in the index dairy herd were screened for bTB with the caudal fold test (CFT), and cattle ≥ 6 months old were also screened with a γ-interferon (γIFN) assay. The index herd was depopulated along with all barn cats and a dog that were fed unpasteurized milk from the herd. Select isolates from M bovis-infected animals from the index herd and other bTB-affected herds underwent WGS. Wildlife around all affected premises was examined for bTB. RESULTS No evidence of bTB was found in any wildlife examined. Within the index herd, 53 of 451 (11.8%) cattle and 12 of 21 (57%) cats were confirmed to be infected with M bovis. Prevalence of M bovis-infected cattle was greatest among 4- to 7-month-old calves (16/49 [33%]) followed by adult cows (36/203 [18%]). The apparent sensitivity and specificity were 86.8% and 92.7% for the CFT and 80.4% and 96.5% for the γIFN assay when results for those tests were interpreted separately and 96.1% and 91.7% when results were interpreted in parallel. Results of WGS revealed that M bovis-infected barn cats and cattle from the index herd and 6 beef operations were infected with the same strain of M bovis. Of the 6 bTB-affected beef operations identified during the investigation, 3 were linked to the index herd only by WGS results; there was no record of movement of livestock or waste milk from the index herd to those operations. CONCLUSIONS AND CLINICAL RELEVANCE Whole-genome sequencing enhanced the epidemiological investigation and should be used in all disease investigations. Performing the CFT and γIFN assay in parallel improved the antemortem ability to detect M bovis
Santman-Berends, I M G A; Mars, M H; van Duijn, L; van Schaik, G
Bovine viral diarrhea virus (BVDV) is an important endemic infection. However, no information was available on whether it would be economically beneficial to implement a national control program in the Netherlands. Therefore, a stochastic simulation model was developed in which control scenarios were added to compare the epidemiological and economic consequences of BVDV control in Dutch dairy herds in the next 10 yr. In the epidemiological part of the model, herds could be classified as susceptible, infectious, recovered, or vaccinated. The outputs of the epidemiological module served as input for the economic module. Net costs that could be attributed to bovine viral diarrhea consisted of production losses, costs for testing, and culling persistently infected cattle in the present voluntary Dutch BVDV control program and costs for vaccination. Four different control scenarios were simulated, involving testing and culling of persistently infected (based on serum or ear-notch testing), and monitoring BVDV statuses and vaccination and were derived from BVDV control programs that are currently executed in Europe. The costs and benefits of BVDV control in the current situation and in each of the simulated control scenarios were evaluated assuming an annual discount rate of 2%. The model estimated a mean BVDV herd prevalence of 18.0% in 2014 and showed a slightly decreasing prevalence over time. The outputs seemed realistic for the present situation in the Netherlands when compared with actual survey data. The average annual net costs associated with bovine viral diarrhea were estimated at €27.8 million for the dairy industry. Two control scenarios were beneficial in controlling BVDV during the study period (between 2015 and 2025). In the scenario where tracing and removing of PI animals and monitoring of the subsequent status was obligatory, the benefit to cost (B/C) ratio was 1.5 (€1.5 benefit for each invested euro). In the scenario in which the BVDV status of
Elmoslemany, A M; Keefe, G P; Dohoo, I R; Jayarao, B M
The objective of this study was to determine on-farm risk factors for bacteriological quality of bulk tank milk. Bulk tank raw milk quality was evaluated on all Prince Edward Island dairy herds (n = 235) over a 2-yr period (March 2005 to March 2007). Biweekly total bacterial, preliminary incubation, laboratory pasteurization, and coliform counts were conducted using a Petrifilm culture system. For the assessment of risk factors, a case-control study was conducted from January 2006 to May 2007. Case and control herds were defined based on the last 6 analyses of bulk tank bacterial counts before on-farm evaluation. Cases were herds that had multiple elevated counts for any of the parameters measured. A total of 69 herds (39 cases and 30 control herds) were evaluated. Data collection included 1) observation and questionnaire on basic hygiene and farm management practices; 2) complete wash analysis of the milking equipment, monitoring the presence of bacterial films on equipment and evaluation of cooling system function; and 3) environmental and cow hygiene scoring. Data were analyzed using multivariable logistic regression. The results of the final model indicated that high alkalinity in the wash water and poor teat-end cleanliness were associated with high bacterial counts in bulk tank milk (odds ratios = 12 and 5.3, respectively). It was also observed that high water temperature of detergent wash and the use of a water softener were associated with low bacterial counts in bulk tank milk (odds ratios = 0.87 and 0.11, respectively). A significant association between udder hair clipping and teat-end cleanliness was also observed. In conclusion, this study highlights the importance of udder hygiene and milking system washing factors on hygienic quality of bulk tank milk.
Nielsen, Eva M.
. Serotype 2 was especially prevalent among calves (68% of the positive calves). In eight of the 20 positive herds, all isolates had the same sero- and PFGE type while, in the other herds, two to five different types were isolated. Conclusions: Significant differences were found between age groups...
Vaarst, Mette; Hindhede, Jens; Enevoldsen, Carsten
Records of claw trimmings were analyzed in seven organic and six conventional Danish herds (a total of 974 cows). The housing systems represented were tie stall systems, loose housing system with slatted floor (one organic herd), and deep litter systems (deep straw bedding). Occurrence of sole...
Kashongwe, O B; Bebe, B O; Matofari, J W; Huelsebusch, C G
Associations between feeding practices, milk yield, and composition were assessed in smallholder rural and peri-urban dairy cow (n = 97) and pastoral camel (n = 15) herds. A cross-sectional survey supplemented by follow-up collection of feed and milk samples for laboratory analyses was conducted. Data was analyzed using descriptive, correlation, and analysis of variance statistics. Feeding practices in rural smallholder dairy cows' herds were pastured based (87.7%) with napier grass (89.4%) and concentrates (93.9%) as forage and concentrate supplements. In smallholder peri-urban dairy cows' herds, it was napier grass based (68.4%) with concentrates (100%), oat forages (42.9%), and crop residues (28.6%). Pastoral camel herds were shrub browsing (53%), rangeland pasture grazing (20%), or Euphorbia tirucalli feeding (27%). Smallholder rural farmers offered more feeds (16.1 vs 15.3 kg/day) than peri-urban farmers, hence net energy for lactation (1.4 vs 1.3 Mcal/kg), crude protein (CP) (10 vs 12%), and milk yields (12 vs 9 kg/herd/day) was higher. Milk fat was higher in smallholder peri-urban (4.3%) than that of rural (3.9%). In pastoral camels, E. tirucalli feeding had higher daily milk yield/herd, fat, and CP (63 kg, 4.5 and 3.6%) than shrub browsing (35 kg, 4.2 and 3.0%) and grazing (23 kg yield, 2.6 and 2.7%). Five feeding practices out of 14 in smallholder dairy cattle herds resulted in more than 10 kg milk/cow/day because of low forage-to-concentrate ratio (2.5), inclusion of legume crop residue, or processing forages. They present opportunities for improved production in smallholder herds. In pastoral camel, E. tirucalli feeding showed the highest potential.
Condas, Larissa A Z; De Buck, Jeroen; Nobrega, Diego B; Carson, Domonique A; Naushad, Sohail; De Vliegher, Sarne; Zadoks, Ruth N; Middleton, John R; Dufour, Simon; Kastelic, John P; Barkema, Herman W
. simulans, S. xylosus, S. cohnii, Staphylococcus saprophyticus, S. capitis, and Staphylococcus arlettae IMI was higher in tiestall barns; the prevalence of S. epidermidis IMI was lowest; and the prevalence of S. chromogenes and Staphylococcus sciuri IMI was highest in bedded-pack barns. Staphylococcus simulans, S. epidermidis, S. xylosus, and S. cohnii IMI were more prevalent in herds with intermediate to high bulk milk somatic cell count (BMSCC) and S. haemolyticus IMI was more prevalent in herds with high BMSCC, whereas other common NAS species IMI were equally prevalent in all 3 BMSCC categories. Distribution of NAS species IMI differed among the 4 regions of Canada. In conclusion, distribution differed considerably among NAS species IMI; therefore, accurate identification (species level) is essential for studying NAS epidemiology. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Clinical metabolic disorders and clinical puerperal complications were not affected by chromium methionine supplementation. The results of this experiment showed that chromium methionine supplementation in multiparous dairy cows diet may improve their reproductive performance in transition period. Key words: Dairy ...
Lane, Elizabeth A; Crowe, Mark A; Beltman, Marijke E; More, Simon J
Herd management record analysis facilitates accurate assessment of the current herd reproductive status; a crucial decision making tool to implement effective change. To determine the relative importance of cow and management factors on reproductive indices in moderate-yielding Irish seasonal-calving dairy herds, breeding records of 1173 cows were collected from 10 seasonal calving herds between 2007 and 2009. Backward-stepwise multivariable logistic regression analysis was utilised to determine the effect of cow factors including parity, calving timing, days post partum, heat detection accuracy and herd factors including herd size and heat detection efficiency on key reproductive indices. Mean farm six-week pregnancy and end of season not-in-calf rate were 46% (range 14-72%) and 22% (range 3-40%), respectively. Oestrous detection efficiency (Pcow parity were not associated (P>0.05) with either outcome when factors including existing calving pattern and heat detection accuracy and efficiency were accounted for. The existing spread in calving pattern, heat detection quality and length of voluntary waiting period were the most influential factors that reduced fertility performance in seasonal-calving herds. Copyright © 2013 Elsevier B.V. All rights reserved.
Eldon, J.; Olafsson, T.; Thorsteinsson, T.
The aim of the studies was to monitor the reproductive performance of Icelandic dairy cow herds with and without histories of fertility problems under normal farming conditions. Artificial inseminations and calvings were recorded, pregnancy was diagnosed by rectal palpation, and progesterone concentration was measured by radioimmunoassay in sequential samples of milk. Blood samples were collected at regular intervals and the concentrations of glucose, urea, calcium and magnesium were determined. Clinical ketosis and low glucose were found in one third of the cows on problem farms. The mean time of first post-partum ovulation was 49 days for cows with ketosis, compared with 34 days for cows free of ketosis. Cows in the normal herds ovulated considerably later than is reported for many other breeds of dairy cows; however, the time of first post-partum AI, the time of conception and the conception rate were similar to those reported for other breeds. The effects of season and herd were statistically significant for the time of first post-partum ovulation, AI and conception; the effect of area was highly significant for the time of ovulation. Progesterone profiles showed that over 50% of the first post-partum ovarian cycles were short and had low progesterone concentrations. Season had significant effects on the length of the interval from calving to first post-partum ovulation, AI and conception, on the conception rate to first AI and consequently on the number of AIs per conception, and on the blood levels of glucose, urea and calcium. (author). 28 refs, 3 figs, 3 tabs
Rahimi, Ebrahim; Ameri, Mehrdad; Karim, Guity; Doosti, Abbas
Q fever is a widespread zoonosis caused by the obligate intracellular micro-organism Coxiella burnetii. The objective of this study was to determine the prevalence rate of C. burnetii in bulk milk samples from dairy bovine, ovine, caprine, and camel herds in Isfahan province, Iran. In the present study, 567 bulk milk samples from 186 dairy bovine, ovine, caprine, and camel herds were tested for C. burnetii using a nested polymerase chain reaction assay. The animals whose milk samples collected for this study were clinically healthy. In total, 8 of 247 (3.2%) bovine milk samples were positive; the positive samples originated from 6 of 90 (6.7%) dairy herds. Eight of 140 (5.7%) ovine bulk milk samples from 42 sheep breeding farms and 5 of 110 (4.5%) caprine bulk milk samples from 32 goat breeding farms were positive for C. burnetii. One of 70 (1.4%) camel bulk milk samples from 22 camel breeding farms was also positive for C. burnetii. Although no extensive prevalence study was undertaken, the results of this study indicate that clinically healthy dairy animals are important sources of C. burnetii infection in Iran. To the authors' knowledge, this study is the first report of direct identification of C. burnetii using polymerase chain reaction in bulk milk samples from dairy ovine herds in Iran and the first report of direct identification of C. burnetii in bulk milk samples from dairy camel herds. Further intensive prevalence studies on Coxiella infection and on possible risks of dairy products will be needed to elucidate the epidemiology of Q fever in Iran.
Enevoldsen, Carsten; Sørensen, J.T.; Thysen, Iver
. The prognostic process synthesized the obtained information into short- or long-term prognoses for the herd through a complex herd simulation model. Site specificity of parameter estimation and forecasting and explorability of assumptions and results were major characteristics of the approach. A user acceptance...... problem related to the simulation was addressed through a simultaneous process of development and validation during the introduction of the program framework into veterinary practices. The generally slow adoption of herd simulation models in extension work could be due to lack of credibility of the models...
Full Text Available In five herds of purebred Holstein dairy cows, altogether 220 bulk milk samples were collected with the following average parameters: rennet coagulation time (RCT 265.2 sec., titratable acidity 6.40 °SH, active acidity 6.72 pH, specific density 1.0281 kg.l−1, fat content 3.81 g.100g−1, protein content 3.28 g.100g−1, lactose content 4.72 g.100g−1, and content of solids non-fat content 8.89 g.100g−1; average values of milk batch volume per herd and diurnal air temperature were 6,072 kg and 8.02 °C, respectively. It was found out that the variable “season“ (spring, summer, autumn or winter significantly influenced nearly all parameters under study (the only exceptions were values of titratable acidity and milk batch volume. As compared with all other seasons, the significantly shortest RCT was recorded in summer. Further it was also found out that the variable “herd” influenced all parameters with the exception of average diurnal air temperature. Regardless to differences existing among individual herds, the shortest average RCT was recorded always in summer.
Bethany E. Griffiths
Full Text Available Lameness is one of the most pressing issues within the dairy industry; it has severe economic implications while causing a serious impact on animal welfare. A study conducted approximately 10 years ago found the within farm lameness prevalence in the UK to be 36.8%. Our objective here is to provide an update on within farm lameness prevalence in the UK, and to provide further evidence on farm level risk factors. A convenience sample of 61 dairy farms were recruited across England and Wales from September 2015 to December 2016. A single farm visit was made and the milking herd was mobility scored, as the cows exited the milking parlor after morning, afternoon, or evening milking. Information regarding the farm and management system was then collected using a short interview with the farmer followed by collection of various subjective and objective measurements of the environment. The same, trained researcher performed all animal and facility-based measures on all visits. A series of univariable analyses were conducted to evaluate the association between various risk factors and herd lameness prevalence (logit transformed. A multivariable linear regression model was then fitted. The median number of milking cows per herd was 193, ranging from 74 to 1,519 cows. The mean within farm lameness prevalence was 31.6%, ranging from 5.8 to 65.4%. In total, 14,700 cows were mobility scored with 4,145 cows found to be lame (28.2%. A number of risk factors were associated with lameness at the univariable analysis level. Categorical risk factors retained in the final model were: resting area type, collecting yard groove spacing width, whether farms were undertaking the 60- to 100-day post calving claw trimming and the frequency of footbathing in the winter. The amount of concentrates fed in the milking parlors or out of parlor feeders was also associated with lameness prevalence. The results of this study have provided an update on the UK herd lameness
Brownlie, T S; Morton, J M; McDougall, S
To describe the accuracy of transrectal ultrasonography for predicting calving dates in dairy cows under typical New Zealand conditions and to assess potential risk factors for differences between predicted and actual calving dates. Data were collected from 116 seasonally calving herds over 2 years in a retrospective single cohort study. Transrectal ultrasonography was undertaken by experienced veterinarians (n=12) to determine if cows were pregnant, and if so to estimate fetal age. Predicted calving date was calculated by adding 282 days to the estimated conception date. Accuracy was assessed using differences between predicted and actual calving dates for each animal. Potential risk factors for animals calving >10 days before or after their predicted calving date were assessed using multinomial logistic regression models. The study population comprised 83,104 cows over the 2 years of the study; 75,037 (90.3%) cows calved within 10 days of their predicted calving date, 3,683 (4.4%) calved >10 days earlier, and 4,384 (5.3%) >10 days later, than predicted. Risk factors for calving >10 days before or after the predicted calving date included having >1 artificial insemination (AI) before pregnancy diagnosis (p=0.03), where the cow's most recent AI was 10 days later than predicted also increased when the fetus was ≥13 weeks old at pregnancy diagnosis (p90% of cows diagnosed pregnant by veterinarians using transrectal ultrasonography calved within 10 days of the predicted calving date. In herds where herd reproductive performance is high, it would be expected that more cows would conceive to their first AI, and potentially fewer cows would have AI close to the end of the herd's AI period, which would increase diagnostic accuracy. Where herd managers rely on accurate predicted calving dates they should be informed about realistic expected accuracy. For greatest accuracy, a complete AI history should be made available to the person performing the pregnancy diagnoses and
Vosough Ahmadi, B.; Frankena, K.; Turner, J.; Velthuis, A.G.J.; Hogeveen, H.; Huirne, R.B.M.
A transmission model developed to investigate the dynamics of Escherichia coli O157:H7 bacteria in a typical Dutch dairy herd was used to assess the effectiveness of vaccination, diet modification, probiotics (colicin) and hygienic measures as to water troughs and bedding, when they are applied
Mele, M; Macciotta, N P P; Cecchinato, A; Conte, G; Schiavon, S; Bittante, G
We investigated the potential of using multivariate factor analysis to extract metabolic information from data on the quantity and quality of milk produced under different management systems. We collected data from individual milk samples taken from 1,158 Brown Swiss cows farmed in 85 traditional or modern herds in Trento Province (Italy). Factor analysis was carried out on 47 individual fatty acids, milk yield, and 5 compositional milk traits (fat, protein, casein, and lactose contents, somatic cell score). According to a previous study on multivariate factor analysis, a variable was considered to be associated with a specific factor if the absolute value of its correlation with the factor was ≥0.60. The extracted factors were representative of the following 12 groups of fatty acids or functions: de novo fatty acids, branched fatty acid-milk yield, biohydrogenation, long-chain fatty acids, desaturation, short-chain fatty acids, milk protein and fat contents, odd fatty acids, conjugated linoleic acids, linoleic acid, udder health, and vaccelenic acid. Only 5 fatty acids showed small correlations with these groups. Factor analysis suggested the existence of differences in the metabolic pathways for de novo short- and medium-chain fatty acids and Δ 9 -desaturase products. An ANOVA of factor scores highlighted significant effects of the dairy farming system (traditional or modern), season, herd/date, parity, and days in milk. Factor behavior across levels of fixed factors was consistent with current knowledge. For example, compared with cows farmed in modern herds, those in traditional herds had higher scores for branched fatty acids, which were inversely associated with milk yield; primiparous cows had lower scores than older cows for de novo fatty acids, probably due to a larger contribution of lipids mobilized from body depots on milk fat yield. The statistical approach allowed us to reduce a large number of variables to a few latent factors with biological
Between 2007 and 2009, the largest human Q fever epidemic ever described occurred in the Netherlands. The source was traced back to dairy goat farms, where abortion storms caused by Coxiella burnetii had been observed. Intervention measures included vaccination of dairy goats, followed by one-time
The study described in this thesis focusses on the health related culling decision in dairy cows, with special attention to the role of farmer's attitude in this process. This thesis is composed of four parts. In the first part, the associations between diseases and culling in dairy cows
Keshavarzi, Hamideh; Sadeghi-Sefidmazgi, Ali; Stygar, Anna Helena
days after calving (2nd – 14th estrus cycle (3-WIM period)). After eliminating outliers and periods with missing records, the dataset included 200,580 insemination records of 31,830 cows observed between 2004 and 2014. A logistic regression model was developed to evaluate the effects of herd, parity......, calving season, cumulative fat corrected milk yield level (CFCML), mastitis in current 3-weeks in milk period (MAS), experience of mastitis in previous 3-WIM periods (EMAS), days in milk for insemination (IDIM) and all significant 2-way interactions on CR. Overall, the CR (total cows pregnant/total number...... of the investigated factors on CR also differed between herds. The odds of conception decreased with higher parity, MAS incidence, and calving during warm seasons. The CFCML significantly interacted with other factors. Therefore the odds of conception for high or low yielding cows will depend on the herd, parity...
Dohoo, I.R.; Tillard, E.; Stryhn, H.
Sources of variation in measures of reproductive performance in dairy cattle were evaluated using data collected from 3207 lactations in 1570 cows in 50 herds from five geographic regions of Reunion Island (located off the cast coast of Madagascar). Three continuously distributed reproductive...
Lunardi, Michele; de Camargo Tozato, Claudia; Alfieri, Alice Fernandes; de Alcântara, Brígida Kussumoto; Vilas-Boas, Laurival Antonio; Otonel, Rodrigo Alejandro Arellano; Headley, Selwyn Arlington; Alfieri, Amauri Alcindo
Teat papillomatosis affects dairy cows worldwide. Milking can become difficult due to teat warts, and maintaining affected cows in the herds may diminish economic profit in the dairy industry. Currently, 13 bovine papillomavirus (BPV) types have been fully characterized, and numerous putative BPV types have been identified through partial L1 gene PCR. In order to identify the viral types present in warts on the udders of dairy cows, 40 teat lesions from 24 cows from 13 cattle farms in three States of Brazil were evaluated by PV L1 gene PCR. The warts that were evaluated contained sequences from BPVs 6-10, the putative BPV types BAPV9 and BAPV4, and two unreported putative papillomavirus (PV) types, named BPV/BR-UEL6 and BPV/BR-UEL7. In addition, mixed infections and coinfections were identified, since more than one lesion was observed on the udders of 13 cows. Phylogenetic analysis showed that BPV/BR-UEL6 is closely related to BPVs belonging to the genus Xipapillomavirus, while BPV/BR-UEL7 clustered with the previously reported strains Cervus timorensis and Pudu puda PVs, which represent a putative new PV type, and it was only distantly related to xi-, epsilon-, delta- and dyoxi-PVs. These results provide information that will assist in the understanding of the association of BPVs 6, 7, 8, 9, and 10, as well as putative BPV types BAPV4 and BAPV9, with mammary papillomatosis. This is the first characterization of putative novel PV types BPV/BR-UEL6 and BPV/BR-UEL7 in teat warts of dairy cows, highlighting the high genetic diversity of BPVs associated with teat papillomatosis.
Blomqvist, Gunilla; Ullman, Karin; Segall, Thomas; Hauzenberger, Elenor; Renström, Lena; Persson-Waller, Karin; Leijon, Mikael; Valarcher, Jean-Francois
Species Pseudocowpox virus (PCPV; family Poxviridae) is known to cause pustular cutaneous disease in cattle. We describe an outbreak of pseudocowpox with an unusual clinical picture in a free-stall dairy herd of ~80 cows. Approximately 90% of the cows had vesicles, erosions, papules, and scabs on the vulva and vaginal mucosa. Histologic analysis of biopsy tissues indicated a primary, although not specified, viral infection. Transmission electron microscopy revealed parapoxvirus particles in both tissue and vesicular materials. Deep sequencing analysis of extracted DNA from swabbed vesicle areas gave a contig of nearly 120,000 nucleotides, matching the PCPV strain VR 634 with 100% identity. Analyses confirmed the absence of other potential causes of pustular vulvovaginitis such as bovine herpesvirus 1 and Ureaplasma diversum. A rolling cow brush was suspected to be the fomite.
Duval, J E; Bareille, N; Madouasse, A; de Joybert, M; Sjöström, K; Emanuelson, U; Bonnet-Beaugrand, F; Fourichon, C
Animal health planning activities are not always providing a satisfactory positive impact on herd health and welfare. Moreover, evaluating the impact of advisory programmes is complex due to multiple interacting elements that influence its outcome. Therefore, measuring solely health outcomes is not sufficient: the whole process of the implementation and use of such programmes should be evaluated. In order to evaluate the impact of an intervention with a Herd Health and Production Management (HHPM) programme a process evaluation framework was designed and used. The intervention involved 20 organic dairy cattle farmers and their advisors, in both France and Sweden. In both countries 20 organic dairy farms were selected as control herds. The evaluation of the HHPM programme was based on: (a) the compliance to the programme; (b) the programme's functions influencing herd health management practices and stimulating dialogue between farmers and advisors; (c) its effectiveness in terms of improving herd health compared with control farms. Complete compliance to the programme was fulfilled by 21 out of 40 farmers-advisors. Results from a questionnaire showed that the programme functioned as intended (e.g. by allowing early identification of herd health problems), stimulated change in farmers' herd health management practices and farmer-advisor dialogue. Even though the majority of the users perceived that the programme contributed to herd health improvements, no significant differences in health outcomes were found when compared with control farms 12 months after the start of the intervention. The programme allowed creating an environment promoting the exchange of information between farmers and advisors, necessary to define pertinent advice in a farm-specific situation. Future research should aim at improving methods for the evaluation of the effect of advisory programmes, by identifying early indicators for effective advice and developing methods to evaluate the quality
Otten, Nina; Nielsen, Liza Rosenbaum; Thomsen, Peter T.
AWL) defined as occurrence of at least one of the two most frequently violated measures found at recent inspections in Denmark, namely (a) presence of injured animals not separated from the rest of the group and/or (b) animals in a condition warranting euthanasia still being present in the herd. A total of 25...
Bontje, D.M.; Backer, J.A.; Roest, H.I.J.; Asseldonk, van M.A.P.M.; Bergevoet, R.H.M.; Roermund, van H.J.W.
To analyse the disease dynamics in goat herds and to study the effect of control measures, a Q fever transmission model was developed by CVI. With such a model we can study questions like ‘What strategy can lower the incidence of Q fever in goats or even lead to disease extinction?’ and ‘Is
Tremetsberger, Lukas; Leeb, Christine; Winckler, Christoph
Animal health and welfare planning is considered an important tool for herd management; however, its effectiveness is less well known. The aim of this study was to conduct animal health and welfare planning on 34 Austrian dairy farms and to evaluate changes in health and welfare after 1 yr. After an initial assessment using the Welfare Quality protocol (Welfare Quality Consortium, Lelystad, the Netherlands), results were reported back to the farmers. Health and welfare area(s) in which both the farmer and the researcher regarded improvement as important were discussed. Management practices and husbandry measures were chosen according to the respective farm situation. One year after interventions had been initiated, farms were reassessed, and the degree of implementation of improvement measures was recorded. The average implementation rate was 57% and thus relatively high when compared with other studies. High degrees of implementation were achieved related to cleanliness and udder health, at 77 and 63%, respectively. Intervention measures addressing udder health were mostly easy to incorporate in the daily routine and led to a reduced somatic cell score, whereas this score increased in herds without implementation of measures. The decrease in cows with dirty teats was more pronounced when measures were implemented compared with control farms. The implementation rate regarding leg health (46%) was comparably low in the present study, and leg health did not improve even when measures were implemented. Lying comfort, social behavior, and human-animal relationship did not require interventions and were therefore seldom chosen by farmers as part of health and welfare plans. In conclusion, the structured, participatory process of animal health and welfare planning appears to be a promising way to improve at least some animal health and welfare issues. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Fanke, Jane; Charlier, Johannes; Steppin, Torsten; von Samson-Himmelstjerna, Georg; Vercruysse, Jozef; Demeler, Janina
The aim of the current study was to estimate economic costs of Ostertagia ostertagi and Fasciola hepatica infections in dairy cattle herds in Germany using the online calculation programme Paracalc ® . Following a questionnaire, survey data were available from 464 farms in 14 federal states. On those farms bulk tank milk (BTM) samples and additionally up to six serum samples collected from first season grazing calves were analysed, using a commercially available ELISA (Boehringer Ingelheim SVANOVA Biotech AB, Uppsala, Sweden), an in-house ELISA (F. hepatica) and an in-house serum pepsinogen test. In total, samples obtained from 344 farms were included in the analysis since those were the only farms with complete questionnaires. Median costs per farm and year were estimated for gastrointestinal (GI) nematode infections (€721.38) and F. hepatica infection (€565.61). Decreases in milk yield in multiparous cows were the major reason for annual production losses due to GI nematodes (€13.33 per cow) and F. hepatica infections (€7.95 per cow), which was followed by annual costs for anthelmintic treatment against GI nematode infections in adult cows (€10.00 per cow) and F. hepatica infection associated annual costs due to repeated artificial insemination (€10.13 per cow) and prolonged calving intervals (€9.40 per cow). The study demonstrated that if all required information is provided, the Paracalc ® tool can assist to identify productions losses in dairy cattle herds due to helminth infections and to optimise farm economics in Germany. Copyright © 2017 Elsevier B.V. All rights reserved.
Darío Cedeño Q.
Full Text Available Objective. To determine seroprevalence and risk factors associated to Neospora caninum in non-vaccinated dairy cattle against infectious agents of reproductive syndrome in the municipality of Pasto, Colombia. Materials and methods. Farms over 2527 meters over sea level were selected, a total of 238 serum samples of Holstein cows were collected and analyzed using the indirect ELISA test to determine N. caninum seropositivity. An epidemiological survey was realized in each herd which included variables related to health and management measures of cattle. A multivariate analysis of binary logistic regression was used with a confidence interval of 95% (p<0.05 using SPSS19® program. Results. The estimated prevalence of N. caninum was 76.9%. The risk factors associated to neosporosis infection in the analyzed farms are as follows: residues of abortions generally left outdoors and not buried (OR 3.81, 95% CI 1.5 - 9.6; dogs fed with leftovers (OR 15.44 IC 95% 1.94-123.22 and bulls allowed to mate with cows (OR 19.68, 95% CI 2.34 - 165.52. Conclusions. The high prevalence of N. caninum and the low abortion rate in dairy herds of the municipality of Pasto corroborated no existence of the disease in all animals serologically positive, but it did suggest that at some point in their lives they were exposed to N. caninum. From the identified risk factors in this study, recommendations can be provided for an effective control of reproductive diseases like Neosporosis present in this region.
Baumgartner, Martina; Giffinger, Friederike; Hoppe, Jan Christoph; Spergser, Joachim
This study is reporting an outbreak of subclinical mastitis due to beta-hemolytic group L streptococci in an Austrian dairy herd with a history of high somatic cell count. At the first survey 16 of 33 lactating cows (28 quarters of 132) were cultured positive for beta-hemolytic, CAMP and esculin negative cocci that grew on Columbia blood agar with small grey catalase negative colonies. With the commercial API 20 Strep system (bioMerieux, F) isolates were classified as members of streptococci group L. All tested strains (eight of 28) produced acid from ribose, lactose, trehalose, amidon and glycogen; they hydrolysed hippurate and showed beta-glucuronidase, beta-galactosidase, alkaline phosphatase, leucinaminopeptidase and arginindehydrolase activity. Isolates were sensitive to bacitracin but resistant to tetracycline. Using phenotypic characterisation as well as sequence analysis of the 16S-23S intergenic spacer region of a representative strain, recovered isolates were identified as Streptococcus (S.) dysgalactiae ssp. equisimilis. Mastitis was characterized by normal milk secretions and absence of clinical abnormalities but high elevations of somatic cell count. Based on the characteristics of the strains and on the observations during the first herd survey, contagious transmission during milking as a result of poor milking hygiene was assumed. The mastitis was controlled through implementation of a strict hygiene protocol including use of single-use udder towels, post milking teat desinfection and cluster disinfection between milking cows in combination with antibiotic treatment of infected udders.
Zadoks, Ruth Nicolet
Mastitis is the most common and costly production disease affecting dairy cows. Staphylococcus aureus and Streptococcus uberis are two major mastitis-causing pathogens. Staphylococcus aureus is traditionally classified as contagious pathogen, while Streptococcus uberis is classified as environmental
Charlier, J.; Levecke, B.; Devleesschauwer, B.; Vercruysse, J.; Hogeveen, Henk
Current control practices against gastrointestinal nematodes in dairy cows rely strongly on anthelmintic use. To reduce the development of anthelmintic resistance or disposition of drug residues in the environment, novel control approaches are currently proposed that target anthelmintic treatment to
Full Text Available Caseins are a family of milk proteins that exist in several molecular forms and arethe main proteins present in the bovine milk. Genetic variation of these proteins hasbeen associated with the quality and quantity of cheese derived from milk.This study was focused on possibilities to evaluate the frequency of the K-casein Ballele in dairy herds from the Research and Development Station for Bovine RaisingArad in order to have breeding programs that target an increase in the frequency ofthe B allele in the dairy cattle population.In order to differentiate the favorable genotype for superior composition and highercheese yield, we used simple DNA extraction method from fresh blood andtechniques based on DNA analysis, which include polymerase chain reaction andrestriction fragment length polymorphisms (PCR-RFLP methods. Employing thesetechniques we were able to determine the k-casein genotype of all individuals in agiven population under selection, regardless of sex, age or physiological stage.As a result, it is now possible to include information on milk protein genotypes intomarker assisted selection programs and consequently improve response to selection.
Full Text Available Caseins are a family of milk proteins that exist in several molecular forms and arethe main proteins present in the bovine milk. Genetic variation of these proteins hasbeen associated with the quality and quantity of cheese derived from milk.This study was focused on possibilities to evaluate the frequency of the K-casein Ballele in dairy herds from the Research and Development Station for Bovine RaisingArad in order to have breeding programs that target an increase in the frequency ofthe B allele in the dairy cattle population.In order to differentiate the favorable genotype for superior composition and highercheese yield, we used simple DNA extraction method from fresh blood andtechniques based on DNA analysis, which include polymerase chain reaction andrestriction fragment length polymorphisms (PCR-RFLP methods. Employing thesetechniques we were able to determine the k-casein genotype of all individuals in agiven population under selection, regardless of sex, age or physiological stage.As a result, it is now possible to include information on milk protein genotypes intomarker assisted selection programs and consequently improve response to selection.
Kudahl, Anne Margrethe Braad; Nielsen, S S; Østergaard, Søren
the ranking between the different culling strategies. Increased market price (20%) of replacement heifers made all culling strategies less profitable and made culling based on a milk yield criterion the most profitable culling strategy for a longer period (11 to 13 yr). A 20% reduction in heifer price made...... reproduction management. However, this strategy only stabilized the prevalence and did not reduce it. In the long term (>7 yr from implementation of a strategy), it was most profitable to cull cows immediately or as soon as possible after testing positive the first time. Varying milk prices did not affect...... immediate culling after a positive test the most profitable strategy overall in herds with typical reproduction, and after 9 yr in herd with poor reproduction. To conclude, the ideal culling strategy depends on the aim of intervention, the time horizon, and the reproductive capabilities combined with prices...
Knappe-Poindecker, M.; Gilhuus, M.; Jensen, Tim Kåre
The aim of this study was to assess infectious foot diseases, including identification and characterization of Dichelobacter nodosus and Treponema spp., in herds having problems with interdigital dermatitis (ID) and heel horn erosion (E) and in control herds expected to have few problems. We also....... nodosus by PCR, culture, virulence testing, and serotyping. Biopsies were analyzed by fluorescent in situ hybridization regarding histopathology, identification, and characterization of Treponema spp., and identification of D. nodosus. Interdigital dermatitis was the most frequent foot disease...... with DD, and in 66.0% of cows with healthy feet. All serogroups of D. nodosus except F and M were detected, and all isolates were defined as benign by the gelatin gel test. Treponema spp. were detected in 50.0% of the cows with ID, in 9.1% with E, in 67.5% with ID and E, in all cows with DD, and in 6...
More, S J; Clegg, T A; Lynch, P J; O'Grady, L
Somatic cell count (SCC) limits are a key component of national and international regulation for milk quality. As yet, very limited work has been published on SCC regulatory standards, including on the effect of different approaches to SCC data adjustment and interpretation. This study examines the effect of SCC data adjustment and interpretation, as outlined in current European Union (EU) legislation, on herd eligibility to supply raw milk for processing of dairy products for human consumption, using Irish data for illustration. The study used Irish milk-recording data as a proxy for bulk tank SCC (BTSCC) data, to calculate an unadjusted monthly SCC value for each herd during each month of participation. Subsequently, 4 data adjustments were applied, as outlined in EU and national legislation: seasonal adjustment; 3-mo rolling geometric average, without accounting for a break in the supply; 3-mo rolling geometric average, after accounting for a break in the supply; and seasonal adjustment and 3-mo rolling geometric average combined, after accounting for a break in the supply. Analyses were conducted to examine the effect, during the period from 2004 to 2010, of data adjustment on the percentage of herds with herd SCC >400,000 cells/mL. In all, 4 interpretation scenarios, incorporating different data adjustment combinations, were used to estimate herd eligibility (compliant, under warning, or suspended, as defined by legislation) to supply raw milk for processing. The 4 methods of data adjustment each led to a sizable reduction (6.7, 5.0, 5.3, and 11.1 percentage points, respectively, compared with the unadjusted data) in the percentage of herds exceeding a herd SCC of 400,000 cells/mL. Herd eligibility varied by interpretation scenarios, in particular those incorporating seasonal adjustment. The study provides new perspectives on the effect of data adjustment on herd SCC and of interpretation scenarios on herd eligibility. The results provide an illustrative
O'Brien, D; Capper, J L; Garnsworthy, P C; Grainger, C; Shalloo, L
Life-cycle assessment (LCA) is the preferred methodology to assess carbon footprint per unit of milk. The objective of this case study was to apply an LCA method to compare carbon footprints of high-performance confinement and grass-based dairy farms. Physical performance data from research herds were used to quantify carbon footprints of a high-performance Irish grass-based dairy system and a top-performing United Kingdom (UK) confinement dairy system. For the US confinement dairy system, data from the top 5% of herds of a national database were used. Life-cycle assessment was applied using the same dairy farm greenhouse gas (GHG) model for all dairy systems. The model estimated all on- and off-farm GHG sources associated with dairy production until milk is sold from the farm in kilograms of carbon dioxide equivalents (CO2-eq) and allocated emissions between milk and meat. The carbon footprint of milk was calculated by expressing GHG emissions attributed to milk per tonne of energy-corrected milk (ECM). The comparison showed that when GHG emissions were only attributed to milk, the carbon footprint of milk from the Irish grass-based system (837 kg of CO2-eq/t of ECM) was 5% lower than the UK confinement system (884 kg of CO2-eq/t of ECM) and 7% lower than the US confinement system (898 kg of CO2-eq/t of ECM). However, without grassland carbon sequestration, the grass-based and confinement dairy systems had similar carbon footprints per tonne of ECM. Emission algorithms and allocation of GHG emissions between milk and meat also affected the relative difference and order of dairy system carbon footprints. For instance, depending on the method chosen to allocate emissions between milk and meat, the relative difference between the carbon footprints of grass-based and confinement dairy systems varied by 3 to 22%. This indicates that further harmonization of several aspects of the LCA methodology is required to compare carbon footprints of contrasting dairy systems. In
Ingrid Bortolin Affonso
Full Text Available Bovine respiratory syncytial virus (BRSV causes important lower respiratory tract illness in calves. According to F and G proteins genetic sequences, three BRSV subgroups have been reported and characterized in several countries, showing differences in its distribution. In Brazil, the virus is widely disseminated throughout the herds and the few characterized isolates revealed the solely occurrence of the subgroup B. This study describes the detection and characterization of an untyped BRSV strain from a twenty-days-old calf from a herd without clinical respiratory disease. Nasal swabs were analyzed by RT-nested PCR for the F and G proteins genes. One sample has amplified the F protein gene. Sequencing and subsequent phylogenetic reconstruction were accomplished, revealing that the strain could not be grouped with any other BRSV subgroups reported. This result may suggest that the BRSV is in constantly evolution, even in Brazil, where the vaccination is not a common practice. More detailed studies about BRSV characterization are necessary to know the virus subgroups distribution among the Brazilian herds to recommend appropriated immunoprophylaxis.
Full Text Available A survey of blood selenium (Se concentrations in Norwegian Red heifers and dry period cows was conducted to reveal possible association to management, feeding, health and fertility. Selenium contents were determined in 254 herd blood samples consisting of pooled samples from individual non-lactating animals from herds in 5 counties. The Se concentrations showed a normal distribution with mean 0.09 μg Se/g blood, with a standard deviation (SD of 0.05, and ranged from 0.02 to 0.23 μg/g, with 50 % of the samples being between 0.06 and 0.11 μg/g. The herds with Se concentrations below 0.06 μg/g were smaller (21.4 ± 8.7 cow-years than those with Se levels above 0.11 μg/g (27.5 ± 14.1 cow-years (P pre partum and decreased incidence of mastitis, ovarian cysts and anoestrus/silent oestrus post partum.
Full Text Available A survey of blood selenium (Se concentrations in Norwegian Red heifers and dry period cows was conducted to reveal possible association to management, feeding, health and fertility. Selenium contents were determined in 254 herd blood samples consisting of pooled samples from individual non-lactating animals from herds in 5 counties. The Se concentrations showed a normal distribution with mean 0.09 μg Se/g blood, with a standard deviation (SD of 0.05, and ranged from 0.02 to 0.23 μg/g, with 50 % of the samples being between 0.06 and 0.11 μg/g. The herds with Se concentrations below 0.06 μg/g were smaller (21.4 ± 8.7 cow-years than those with Se levels above 0.11 μg/g (27.5 ± 14.1 cow-years (P pre partum and decreased incidence of mastitis, ovarian cysts and anoestrus/silent oestrus post partum.
Cook, J G; Green, M J
Economic success in dairy herds is heavily reliant on obtaining pregnancies at an early stage of lactation. Our objective in this study was to attempt to predict the likelihood of conception occurring by d 100 and 150 of lactation (days in milk, DIM) by Markov chain Monte Carlo analysis using test day milk recording data and reproductive records gathered retrospectively from 8,750 cows from 33 dairy herds located in the United Kingdom. Overall, 65% of cows recalved with 30, 46, and 65% of cows conceiving by 100 DIM, 150 DIM, and beyond 150 DIM, respectively. Overall conception rate (total cows pregnant/total number of inseminations) was 27.47%. Median and mean calving to conception intervals were 123 and 105 d, respectively. The probability of conception by both 100 DIM and 150 DIM was positively associated with the average daily milk weight produced during the fourth week of lactation (W4MK) and protein percentage for test day samples collected between 0 to 30 and 31 to 60 DIM. Butterfat percentage at 0 to 30 DIM was negatively associated with the probability of conception by 100 DIM but not at 150 DIM. High somatic cell count (SCC) at both 0 to 30 and 31 to 60 DIM was negatively associated with the probability of conception by 100 DIM, whereas high SCC at 31 to 60 DIM was associated with a reduced probability of conception by 150 DIM. Increasing parity was associated with a reduced odds of pregnancy. Posterior predictions of the likelihood of conception for cows categorized as having "good" (W4MK >30kg and protein percentage at 0 to 30 and 31 to 60 DIM >3.2%) or "poor" (W4MK <25kg and protein percentage at 0 to 30 and 31 to 60 DIM <3.0%) early lactation attributes with actual observed values indicated model fit was good. The predicted likelihood of a "good" cow conceiving by 100 and 150 DIM was 0.39 and 0.57, respectively (actual observed values 0.40 and 0.59). The corresponding values for a "poor" cow were 0.28 and 0.42 (actual observed values 0.26 and 0
Ettema, Jehan F.; Østergaard, Søren; Sørensen, Morten Kargo
of a dairy herd including young stock. A daily increasing trend describing genetic milk yield potential of the sire population was included in the model. The inaccuracy of assuming that replacement heifers have the same (milk yield) potential as the cows present in the herd was hereby dealt with. Improving...... on the superior half of all heifers reduced GM by €8 per cow-year when genetic progress was not included and increased the GM by €16 per cow-year when genetic progress was included in the model. Including genetic progress reduced the losses caused by lower conception and estrus detection rates and had a minimal...
As organic grain prices have increased and organic milk prices have decreased, dairy farmers are seeking lower-cost supplementation strategies. Sugarcane molasses, a rich source of sucrose, seems to be a viable option as a source of energy. Molasses frequently costs less per pound of dry matter than...
Romero, J.J.; Perez, E.; Dolz, G.; Frankena, K.
Twenty-five specialised Costa Rican dairy farms (located in the Poás area) were used to determine neosporosis seroprevalence and the association of seropositivity with environmental and management factors. The farms involved were selected intentionally and all of them use VAMPP 5.1 (Veterinary
Background. Dairy farms are known reservoirs of entero-pathogenic E. coli (EPEC). EPEC, or the virulence factors associated with pathogenicity, have been detected in manure, milk, and the farm environment. However, it is unclear which farm compartments are reservoirs contributing to EPEC persistence...
Nielsen, Per Kantsø; Petersen, Mette Bisgaard; Nielsen, Liza Rosenbaum
of this study was to evaluate the herd-level diagnostic performance of an indirect ELISA test by comparison to a real-time PCR test when diagnosing M. bovis in cattle herds of bulk tank milk. Bulk tank milk samples from Danish dairy herds (N=3437) were analysed with both the antibody detecting BIO K 302 M...
Wedderkopp, A.; Stroger, U.; Bitsch, V.
-negative to test-positive in each area was correlated with the incidence of S. Dublin outbreaks in the corresponding county (r = 0.48, n = 19; P third test rounds was not constant (Pr \\t\\ = 0.0001). The study demonstrated that the probability...... of being test-negative in the third test round was 0.926 for a herd with 2 previous test-negative results. It was concluded that the investigated ELISA method was in general accordance with the cases of clinical S. Dublin infection recorded. and that the method has a potential for national screening...
Puillet, L; Martin, O; Sauvant, D; Tichit, M
Finding ways of increasing the efficiency of production systems is a key issue of sustainability. System efficiency is based on long-term individual efficiency, which is highly variable and management driven. To study the effects of management on herd and individual efficiency, we developed the model simulation of goat herd management (SIGHMA). This dynamic model is individual-based and represents the interactions between technical operations (relative to replacement, reproduction and feeding) and individual biological processes (performance dynamics based on energy partitioning and production potential). It simulates outputs at both herd and goat levels over 20 years. A farmer's production project (i.e. a targeted milk production pattern) is represented by configuring the herd into female groups reflecting the organisation of kidding periods. Each group is managed by discrete events applying decision rules to simulate the carrying out of technical operations. The animal level is represented by a set of individual goat models. Each model simulates a goat's biological dynamics through its productive life. It integrates the variability of biological responses driven by genetic scaling parameters (milk production potential and mature body weight), by the regulations of energy partitioning among physiological functions and by responses to diet energy defined by the feeding strategy. A sensitivity analysis shows that herd efficiency was mainly affected by feeding management and to a lesser extent by the herd production potential. The same effects were observed on herd milk feed costs with an even lower difference between production potential and feeding management. SIGHMA was used in a virtual experiment to observe the effects of feeding strategies on herd and individual performances. We found that overfeeding led to a herd production increase and a feed cost decrease. However, this apparent increase in efficiency at the herd level (as feed cost decreased) was related
Kautz, F M; Nickerson, S C; Ely, L O
This investigation evaluated the efficacy of a bacterin in reducing the prevalence of staphylococcal mastitis and somatic cell counts (SCC) in a dairy goat herd. Does were vaccinated or left as controls, and the levels of mastitis and SCC monitored over 18 months. Staphylococcus caprae (42.5%), S. xylosus (15.1%), and S. simulans (10.0%) were the predominant causes of intramammary infections (IMI). The infection rate was 1.64 IMI/doe among vaccinates, which tended to be lower (P mastitis vaccines for use in managing staphylococcal mastitis and SCC in dairy goats. Published by Elsevier Ltd.
Schou, Kirstine Klitgaard; Weiss Nielsen, Martin; Ingerslev, Hans-Christian
The bacteria associated with the infectious claw disease bovine digital dermatitis (DD) are spirochetes of the genus Treponema; however, their environmental reservoir remains unknown. To our knowledge, the current study is the first report of the discovery and phylogenetic characterization of r...... with identification at the operational-taxonomic-unit level. Using treponeme-specific primers in this high-throughput approach, we identified small amounts of DNA (on average 0.6% of the total amount of sequence reads) from DD-associated treponemes in 43 of 64 samples from slurry and cow feces collected from six...... geographically dispersed dairy herds. Species belonging to the Treponema denticola/Treponema pedis-like and Treponema phagedenis-like phylogenetic clusters were among the most prevalent treponemes in both the dairy herd environment and the DD lesions. By the high-throughput approach presented here, we have...
Stevens, M; Piepers, S; Supré, K; De Vliegher, S
The main objectives of this study were to quantify the consumption of antimicrobials on a convenience sample of dairy herds and to determine the association between herd-level antimicrobial consumption and inhibition zone diameters (IZD) of non-aureus staphylococci and Staphylococcus aureus isolates from subclinical mastitis cases. Also, the association between the IZD of non-aureus staphylococci and Staph. aureus isolates within a herd was studied. Antimicrobial consumption data on 56 Flemish dairy farms were obtained between 2013 and 2014 by so-called garbage can audits and expressed as antimicrobial treatment incidence (ATI), with the unit of ATI being the number of defined daily doses animal (DDDA) used per 1,000 cow-days. The average total ATI in adult dairy cattle for all active substances was 18.73 DDDA per 1,000 cow-days and ranged from 6.28 to 42.13 DDDA between herds. The ATI of critically important (for human health) antimicrobials was 6.91 DDDA per 1,000 cow-days; that is, 37% of total antimicrobial consumption. The average ATI for intramammary therapy of (sub)clinical mastitis, intramammary dry-cow therapy, and systemically administered therapy was 5.20, 6.70, and 6.73 DDDA, respectively. The IZD of 239 non-aureus staphylococci and 88 Staph. aureus isolates originating from milk samples from cows with subclinical mastitis collected on selected dairy herds were determined using Kirby-Bauer disk diffusion and ranged between 6 and 42 mm. Because only a limited number of clinical breakpoints (Clinical and Laboratory Standards Institute) and epidemiological cut-off values (European Committee on Antimicrobial Susceptibility Testing) are available for mastitis-causing bacteria in bovine, IZD were used as a proxy for antimicrobial resistance. Inhibition zone diameters of non-aureus staphylococci for cefquinome, a critically important β-lactam antibiotic, were negatively associated with the ATI of critically important β-lactam for systemically administered
Ivemeyer, Silvia; Bell, Nick J.; Brinkmann, Jan
, farmers take responsibility for health and welfare planning by identifying issues, setting goals, and acting to improve the health situation based on farm-specific data, e.g. milk production. This paper reviews the results from intervention studies that used a modified ‘farmer field school’ approach...... for animal health and welfare planning, providing an overview of ongoing activities and their implementation into advisory situations in selected European countries. Studies on stable schools as an intervention tool showed improvements regarding the specific project aim on the majority of the participating...... farms. Farmers and facilitators were convinced of the approach and benefits for dairy herds. Farmers’ attitude and attention towards their herds and their ownership of the process appear to be crucial success factors for herd health and welfare situations. In some European countries, this method has...
Chand, Puran; Chhabra, Rajesh
Herd and individual animal prevalence along with associated risk factors of bovine brucellosis was assessed on dairy farms located in 22 districts in Haryana and Punjab of India. Examination of 4,580 female animals of 119 dairy farms by Rose Bengal test and enzyme-linked immunosorbent assay revealed that an overall herd prevalence was 65.54% (78/119) and individual animal prevalence was 26.50 % (1,214/4,580). Herd prevalence in Haryana was 62.79% which was not significantly different (P = 0.4208) from Punjab (72.72%). Individual animal prevalence was 34.15% in Punjab which was significantly higher (P brucellosis on dairy farms was detected in 20 of the 22 districts, of which 12 districts were in Haryana and 8 in Punjab. Risk factors such as species of animals, age of animals, herd size, awareness of dairymen for brucellosis, entry of a purchased animals on the farm, abortion on farm, use of calving pens, type of breeding, and type of farming were analyzed. The study indicated that the odds ratio (OR) was significant with risk factors of species (OR = 1.63; 95 %CI = 1.40-1.90; P brucellosis among dairymen (OR = 21.65; 95%CI = 2.63-178.04; P = 0.0042), entry of purchased animal on the farm (OR = 9.16; 95%CI = 2.38-35.18; P = 0.0012), abortion in animals (OR = 5.57; 95%CI = 1.92-16.10; P = 0.0015) and on cow farm (OR = 3.43; 95 %CI = 1.33-8.82; P = 0.0105). While the OR was insignificant (P > 0.05) with risk factors of herd size, use of calving pen on farms, type of breeding and on buffalo and mixed type of farms.
Klitgaard, Kirstine; Nielsen, Martin W; Ingerslev, Hans-Christian; Boye, Mette; Jensen, Tim K
The bacteria associated with the infectious claw disease bovine digital dermatitis (DD) are spirochetes of the genus Treponema; however, their environmental reservoir remains unknown. To our knowledge, the current study is the first report of the discovery and phylogenetic characterization of rRNA gene sequences from DD-associated treponemes in the dairy herd environment. Although the spread of DD appears to be facilitated by wet floors covered with slurry, no DD-associated treponemes have been isolated from this environment previously. Consequently, there is a lack of knowledge about the spread of this disease among cows within a herd as well as between herds. To address the issue of DD infection reservoirs, we searched for evidence of DD-associated treponemes in fresh feces, in slurry, and in hoof lesions by deep sequencing of the V3 and V4 hypervariable regions of the 16S rRNA gene coupled with identification at the operational-taxonomic-unit level. Using treponeme-specific primers in this high-throughput approach, we identified small amounts of DNA (on average 0.6% of the total amount of sequence reads) from DD-associated treponemes in 43 of 64 samples from slurry and cow feces collected from six geographically dispersed dairy herds. Species belonging to the Treponema denticola/Treponema pedis-like and Treponema phagedenis-like phylogenetic clusters were among the most prevalent treponemes in both the dairy herd environment and the DD lesions. By the high-throughput approach presented here, we have demonstrated that cow feces and environmental slurry are possible reservoirs of DD-associated treponemes. This method should enable further clarification of the etiopathogenesis of DD. Copyright © 2014, American Society for Microbiology. All Rights Reserved.
Selemetas, Nikolaos; Phelan, Paul; O'Kiely, Padraig; de Waal, Theo
Fasciolosis caused by Fasciola hepatica is a widespread parasitic disease in cattle farms. The aim of this study was to detect clusters of fasciolosis in dairy cow herds in Munster Province, Ireland and to identify significant climatic and environmental predictors of the exposure risk. In total, 1,292 dairy herds across Munster was sampled in September 2012 providing a single bulk tank milk (BTM) sample. The analysis of samples by an in-house antibody-detection enzyme-linked immunosorbent assay (ELISA), showed that 65% of the dairy herds (n = 842) had been exposed to F. hepatica. Using the Getis-Ord Gi* statistic, 16 high-risk and 24 low-risk (P <0.01) clusters of fasciolosis were identified. The spatial distribution of high-risk clusters was more dispersed and mainly located in the northern and western regions of Munster compared to the low-risk clusters that were mostly concentrated in the southern and eastern regions. The most significant classes of variables that could reflect the difference between high-risk and low-risk clusters were the total number of wet-days and rain-days, rainfall, the normalized difference vegetation index (NDVI), temperature and soil type. There was a bigger proportion of well-drained soils among the low-risk clusters, whereas poorly drained soils were more common among the high-risk clusters. These results stress the role of precipitation, grazing, temperature and drainage on the life cycle of F. hepatica in the temperate Irish climate. The findings of this study highlight the importance of cluster analysis for identifying significant differences in climatic and environmental variables between high-risk and low-risk clusters of fasciolosis in Irish dairy herds.
Full Text Available Fasciolosis caused by Fasciola hepatica is a widespread parasitic disease in cattle farms. The aim of this study was to detect clusters of fasciolosis in dairy cow herds in Munster Province, Ireland and to identify significant climatic and environmental predictors of the exposure risk. In total, 1,292 dairy herds across Munster was sampled in September 2012 providing a single bulk tank milk (BTM sample. The analysis of samples by an in-house antibody-detection enzyme-linked immunosorbent assay (ELISA, showed that 65% of the dairy herds (n = 842 had been exposed to F. hepatica. Using the Getis-Ord Gi* statistic, 16 high-risk and 24 low-risk (P <0.01 clusters of fasciolosis were identified. The spatial distribution of high-risk clusters was more dispersed and mainly located in the northern and western regions of Munster compared to the low-risk clusters that were mostly concentrated in the southern and eastern regions. The most significant classes of variables that could reflect the difference between high-risk and low-risk clusters were the total number of wet-days and rain-days, rainfall, the normalized difference vegetation index (NDVI, temperature and soil type. There was a bigger proportion of well-drained soils among the low-risk clusters, whereas poorly drained soils were more common among the high-risk clusters. These results stress the role of precipitation, grazing, temperature and drainage on the life cycle of F. hepatica in the temperate Irish climate. The findings of this study highlight the importance of cluster analysis for identifying significant differences in climatic and environmental variables between high-risk and low-risk clusters of fasciolosis in Irish dairy herds.
Vélez, Julián Reyes; Cameron, Marguerite; Rodríguez-Lecompte, Juan Carlos; Xia, Fangfang; Heider, Luke C.; Saab, Matthew; McClure, J. Trenton; Sánchez, Javier
The objectives of this study are to determine the occurrence of antimicrobial resistance (AMR) genes using whole-genome sequence (WGS) of Streptococcus uberis (S. uberis) and Streptococcus dysgalactiae (S. dysgalactiae) isolates, recovered from dairy cows in the Canadian Maritime Provinces. A secondary objective included the exploration of the association between phenotypic AMR and the genomic characteristics (genome size, guanine–cytosine content, and occurrence of unique gene sequences). Initially, 91 isolates were sequenced, and of these isolates, 89 were assembled. Furthermore, 16 isolates were excluded due to larger than expected genomic sizes (>2.3 bp × 1,000 bp). In the final analysis, 73 were used with complete WGS and minimum inhibitory concentration records, which were part of the previous phenotypic AMR study, representing 18 dairy herds from the Maritime region of Canada (1). A total of 23 unique AMR gene sequences were found in the bacterial genomes, with a mean number of 8.1 (minimum: 5; maximum: 13) per genome. Overall, there were 10 AMR genes [ANT(6), TEM-127, TEM-163, TEM-89, TEM-95, Linb, Lnub, Ermb, Ermc, and TetS] present only in S. uberis genomes and 2 genes unique (EF-TU and TEM-71) to the S. dysgalactiae genomes; 11 AMR genes [APH(3′), TEM-1, TEM-136, TEM-157, TEM-47, TetM, bl2b, gyrA, parE, phoP, and rpoB] were found in both bacterial species. Two-way tabulations showed association between the phenotypic susceptibility to lincosamides and the presence of linB (P = 0.002) and lnuB (P genes and the between the presence of tetM (P = 0.015) and tetS (P = 0.064) genes and phenotypic resistance to tetracyclines only for the S. uberis isolates. The logistic model showed that the odds of resistance (to any of the phenotypically tested antimicrobials) was 4.35 times higher when there were >11 AMR genes present in the genome, compared with genes (P resistance was lower for S. dysgalactiae than S. uberis (P = 0
Yeruham, I; Schwimmer, A; Brami, Y
The German wasp, Vespula germanica has been observed to injure teats of dairy cows, causing lesions that are associated with clinical and subclinical mastitis. The presence of skin lesions on the teats, caused by the wasps, was recorded in a dairy cattle herd located in the Samaria foothills during July-October 1999. Wasp-inflicted injuries were found in 43.6% (58 of 133) of the adult cows and 1.4% (one of 71) of the first-calving cows. They were located in 42.4% of cows (n = 25) on all quarters, 18 cows (30.5%) had lesions on the front quarters and 27.1% (n = 16) of cows on the hind quarters only. Clinical and subclinical mastitis were diagnosed in 61% (36 of 59) and 28.8% (17 of 59), respectively, of the injured adult and first-calving cows. The most common bacterial isolates from the mastitic cows were Staphylococcus aureus 45.1% (n = 14), Streptococcus dysgalactiae 16.1% (n = 5), Streptococcus spp. 19.4% (n = 7) and others 13.9% (n = 5). The loss of milk production was estimated at 300 kg milk for each cow injured by wasps and exhibiting clinical mastitis. An increase in the bulk-milk somatic cell count, from 186 x 103 at 1 month prior to the outbreak to a peak of 1200 x 10(3) in the post-outbreak month, was noted. The culling rate reached 13.6% (eight of 59) of the affected cows. In summary, the considerable economic losses caused by the wasp infestation resulted from decreased milk production and a decline in milk quality, culling of affected cows, and increased demand for use of drugs and veterinary care.
Sørensen, Morten Kargo; Andersen, Jakob Voergaard; Pedersen, Louise Dybdahl
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...... 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...
Full Text Available Incidence of health and production problems related to feeding, nutrition and/or metabolism have being growing in dairy herds. Early diagnosis allows their reduction and consequently reduces economic losses. Monitoring nutritional status periodically allows to identify possible causes of nutritional unbalances and/or mistakes in feeding practices and establish corrective measurements.La incidencia de problemas alimenticios, nutricionales y metabólicos es cada vez mayor en hatos lecheros, así como la aparición de problemas sanitarios, productivos y reproductivos asociados a los mismos. La detección oportuna y correcta de éstos permite reducir su incidencia y, por tanto, las pérdidas económicas de los hatos. El monitoreo nutricional periódico hace posible establecer el estado nutricional de una población animal, e identificar las posibles causas de desbalances nutricionales y errores en la alimentación, así como orientar en la toma de decisiones acerca de los correctivos que se deben establecer cuando se detectan problemas. El análisis de las posibles relaciones existentes entre la información aportada por cada uno de los aspectos evaluados en el monitoreo nutricional permite una evaluación más adecuada que su análisis independiente y aislado.
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.
Mekonnen, S A; Koop, G; Melkie, S T; Getahun, C D; Hogeveen, H; Lam, T J G M
Knowledge of mastitis pathogens and their predominance as well as understanding of risk factors are prerequisites to improve udder health in a herd, region or country. In Ethiopia, such information is scarce, despite the fact that mastitis is an important cattle disease in the country. A cross-sectional study that describes prevalence and causative agents of subclinical mastitis (SCM) as well as risk factors at cow and herd level was conducted on 167 dairy farms in North-West Ethiopia. On average, 33% of the quarters and 62% of the cows were California Mastitis Test (CMT) positive, but the within herd quarter level prevalence ranged between 0 and 100%. A total of 1543 milk samples, being 27 quarters that showed signs of CM, 606 CMT positive quarters and 910 CMT negative quarters were cultured, respectively 40%, 67% and 47% was positive on bacteriological culture. Coagulase negative staphylococci (CNS) (31%) followed by Staphylococcus aureus (9%) were the pathogens most frequently isolated. Based on face-to-face questionnaire data, 35 herd level and 13 cow level factors were evaluated for their association with SCM (based on CMT) and with a positive culture for any bacteria, CNS or S. aureus. Cows with a history of CM, of higher parity, >150days in milk (DIM) and herds with owners that have >10th grade level of education had higher odds of SCM. The odds of being culture positive for any bacteria was higher in cows with ≥25% Holstein Friesian blood level (HBL), >150 DIM, housed on cemented floors, and milked by squeezing rather than stripping. Similarly, the odds of culturing CNS was higher in cows with 25-50% HBL, >150 DIM, and milked by squeezing. Staphylococcus aureus was more often found in cows with a history of CM and in larger herds. Checking the udder for mastitis, feeding cows according to their requirements and allowing calves to suckle the cows were negatively associated with SCM, with culturing any bacteria and with culturing CNS, respectively. Higher
Mulligan, F J; O'Grady, L; Rice, D A; Doherty, M L
This paper presents a practical, on-farm approach for the monitoring and prevention of production disease in dairy cattle. This integrated approach, should be used in an interdisciplinary way by farmers, veterinarians, nutrition advisors and other relevant professionals for the improvement of animal health and welfare and producer profitability. The key areas that form the basis for this approach are body condition score management, negative energy balance, hypocalcaemia, rumen health and trace element status. Monitoring criteria are described for each of these key areas, which when considered collectively, will facilitate the assessment of dairy cow health with regard to clinical and subclinical disease. The criteria, which are informed by published scientific literature, are based on farm management and environmental factors, clinical data, milk production records, dietary analysis, and assessment of blood and liver concentrations of various metabolites or trace elements. The aim is to review the efficacy of production disease control measures currently in place, and if necessary to modify them or formulate new ones.
Luís Rodrigo Balarezo Urresta
Full Text Available The objective of this research was to characterize the mineral status of the soil and pasture in of the Andean Ecuadorian region, during the rainy and dry periods, three dairy farms were used as study cases investigated him three dairy farms of the El Carchi province. They determined the chemical indicators of the soil and the pasture, the descriptive statisticians were calculated themselves and it was used a multifactorial ANOVA to determine the main factors affecting them on them, comparing means with Bonferroni and Duncan test. The soil classified as acid lightly, 100 % of the samples presented elevated levels of organic matter, NH4+, Mg, Cu, Zn, Fe and Mn. The farm had a significant effect on the pH, Ca, Mg, K, Cu, Fe, Mg and P, and the climatic period on the organic matter, NH4+, S, Cu and P. Pasture presented deficiencies of Mg, Zn and Na, the other minerals were above the critical limits. The farm affected the Ca, P, Mg, Na and Mn, and the climatic period the levels of Ca, K, Cu y Zn. In conclusion, 100 % soil samples presented high OM, slight acidity, low levels of Ca and high concentrations of NH4+, S, Mg, Cu, Zn and Mn. In pastures, there were diagnosed deficiencies of P, Cu and Zn, and their concentrations differed among farms and the two climatic periods of the year.
Cook, Nigel B; Nordlund, Kenneth V
Free stall housing increases the exposure of dairy cows' claws to concrete walk-ways and to manure between periods of rest, and generally shows the highest rate of lameness compared with other dairy management systems. However, there is great variation within a system, and the rate of new cases of lameness can be reduced to very low levels provided time spent resting per day is maximized through good stall design, access to stalls through stocking density control and comfortable transition cow facilities, limiting the time spent milking, provision of adequate heat abatement, and good leg hygiene. Sand bedded stalls are useful as they also permit lame cows to maintain adequate daily rest. Rubberized alley flooring surfaces benefit the cow by reducing claw wear and trauma compared to concrete, making them ideal for parlor holding areas and long transfer lanes and walk ways. However, caution is required when using rubber floors in pens with uncomfortable stalls due to apparent adverse effects on cow time budgets, which may in turn have a detrimental effect on lameness.
Full Text Available One hundred and fifteen cases of sub clinical mastitis were detected in a study on 510 goats from 5 herds in west central, Iran. From positive milk samples, 23 Staphylococcus spp. strains were isolated. Fourteen isolates were determined as Staphylococcus aureus (12.17%, and the other 9 (7.82% as Staphylococcus epidermidis. Eleven and six isolates of S. aureus and S. epidermidis produced combined form of hemolysins a/ß/d, while ß/d hemolysins produced by 2 and 3 isolates respectively . Only one isolate of S. aureus produced single type d hemolysin. The sensitivity of all strains to 10 chemotherapeutics was tested through the disk diffusion method, 6 strains (26.08% were determined as methicillin-resistant: out of them 4 isolates were S. aureus and 2 S.epidermidis. S. aureus and S. epidermidis isolates were 100% resistant to Cloxaciline and Kanamycin while the resistance to Penicillin was 100% in S. aureus and 33.33% in S. epidermidis isolates. [Vet. World 2010; 3(5.000: 205-208
Wahab, S.; Jainudeen, M.R.; Azizuddin, K.
The paper reports on the reproductive performance of smallholder dairy cross-bred cattle in Malaysia, as monitored by milk progesterone radioimmunoassay and rectal palpation. Infertility was identified as the major problem faced by the smallholder farmers. The results show that there is a strong and significant association between suckling and delayed post-partum ovarian activity. The longer calving intervals in smallholder dairy herds compared with those in institutional herds are due to inactive ovaries rather than failure to detect oestrus. The use of a progesterone releasing intravaginal device (PRID) for treatment of anoestrus resulted in 93% of cows cycling, with a conception rate of 46% to insemination at the induced oestrus. Cows that suckled their calves had significantly longer calving intervals. The mean body score for cattle on smallholder herds was 3.8 -+ 1.1, and fertile cows had significantly higher scores than infertile cows. There was strong evidence to suggest that increased body scores corresponded to shorter intervals between calving and resumption of sexual activity, calving and conception, and successive calvings. (author). 12 refs, 4 tabs
For several years, Ethiopia ranked first in cattle population in Africa. However, the dairy industry is not as developed as that of East African countries including Ethiopia. This study was conducted to assess the reproductive and lactation performance and factors affecting crossbreed dairy cattle in intensive dairy farm in ...
Watters, M E Alexandrea; Meijer, Karin M A; Barkema, Herman W; Leslie, Kenneth E; von Keyserlingk, Marina A G; Devries, Trevor J
Recent evidence suggests that the risk of intramammary infection in dairy cows is related to lying patterns. The objectives of this study were to quantify the standing and lying behavior of dairy cows milked 3×/d, determine the cow- and herd-level factors associated with these behaviors, and relate these findings to the risk of an elevated somatic cell count (SCC). Five commercial free-stall dairy herds in Eastern Ontario, milking 3×/d, were enrolled in a longitudinal study. Forty Holstein-Friesian cows/herd were randomly selected as focal animals based on days in milk (cow SCC was recorded at the beginning of each period and end of the final period. Elevated SCC (eSCC) was used as an indicator of subclinical mastitis. A new incident eSCC was defined as an individual cow that started the period with a SCC cows for hygiene and lameness. Throughout the course of the study, cows averaged 11.2h/d of lying time, split into 8.6 lying bouts/d that were on average 84.6 min in length. Later lactation cows had longer daily lying times that were split into fewer lying bouts of longer duration than cows earlier in lactation. Lame cows had longer daily lying times and lying bout durations than non-lame cows. Cows with greater milk yield had lower lying times than lower producing cows. Average post-milking standing time across the study herds was 103 min. Manipulation of feed (feed delivery or push-up) by the stockperson, in the hour before milking or shortly thereafter, resulted in the longest post-milking standing times. Over the study period, 48 new eSCC were detected, resulting in a mean herd incidence rate of 0.91 eSCC/cow-year at risk for all study herds. A non-linear relationship between post-milking standing time and eSCC incidence was found; compared to those cows that lie down cows that lie down for the first time >90 min after milking had a lower risk of acquiring a new eSCC. The risk of experiencing an eSCC was also increased in multiparous cows, and in those cows
Ramírez, N F; Keefe, G; Dohoo, I; Sánchez, J; Arroyave, O; Cerón, J; Jaramillo, M; Palacio, L G
Mastitis is the main disease entity affecting dairy farms in the Colombian High Plains of northern Antioquia, Colombia. However, no previous epidemiologic studies have determined the characteristics that increase the risk of infection in this region, where manual milking is still the prevailing system of milking. A 24-mo longitudinal study was designed to identify the predominant mastitis pathogens and important herd- and cow-level risk factors. Monthly visits were made to 37 commercial dairy farms to collect herd- and cow-level data and milk samples. Herd size varied from 6 to 136 cows (mean 37.0, median 29). Herd-level factors included type of milking system (manual or mechanical) and a range of management practices recommended by the National Mastitis Council (Madison, WI) to prevent mastitis. Individual cow-level risk factors included parity, stage of lactation, breed, udder hygiene, and lameness. A logistic regression analysis was used to investigate associations between herd- and cow-level risk factors with the presence of subclinical mastitis and infection caused by Streptococcus agalactiae at the quarter level. A quarter was considered to have subclinical mastitis if it had a positive California Mastitis Test and was subsequently confirmed to have a somatic cell count of ≥200,000 cells/mL. Any cow with one or more quarters with subclinical mastitis was considered to have subclinical mastitis at the cow level. Using 17,622 cow observations, the mean prevalence of subclinical mastitis at the cow level was 37.2% (95% confidence interval: 31.2, 43.3) for the first month and did not substantially change throughout the study. The predominant microorganisms isolated from quarters meeting the subclinical mastitis definition were contagious pathogens, including Strep. agalactiae (34.4%), Corynebacterium spp. (13.2%), and Staphylococcus aureus (8.0%). Significant variables associated with subclinical mastitis risk at the quarter level included being a purebred
Marta Bañolas Jobim
Full Text Available In this work, through microbiological examinations, the etiology of bovine mastitis in 628 milk samples coming from dairy farms from Paraná, Santa Catarina and Rio Grande do Sul along the year of 2007 were evaluated. Out of this total 1,382 microorganisms were isolated. By taking into account the total of isolations, the following microorganisms and their percentage, respectively were found: Staphylococcus spp. (30.53%, Escherichia coli (21.64%, Streptococcus bovis (17.08%, Streptococcus agalactiae (11.07%, Enterobacter spp. (7.53%, Pseudomonas spp. (4.12% and others (8.03%. The microorganisms grouped into the others are: Streptococcus spp., Proteus spp., gram negative rods, Shigella spp., Alcaligenes spp., Klebsiella spp., Edwarsiella spp., Citrobacter spp., Serratia spp., Salmonella spp. e Corynebacterium spp. The environmental pathogens predominated among the isolated microorganisms; 33.13% of the cultures presented more than three pathogens, suggesting contamination of the samples; in the mounts of November and December, there was an increase of the samples sent.
Bittante, G; Cipolat-Gotet, C; Malchiodi, F; Sturaro, E; Tagliapietra, F; Schiavon, S; Cecchinato, A
The objectives of this study were to characterize the variation in curd firmness model parameters obtained from coagulating bovine milk samples, and to investigate the effects of the dairy system, season, individual farm, and factors related to individual cows (days in milk and parity). Individual milk samples (n = 1,264) were collected during the evening milking of 85 farms representing different environments and farming systems in the northeastern Italian Alps. The dairy herds were classified into 4 farming system categories: traditional system with tied animals (29 herds), modern dairy systems with traditional feeding based on hay and compound feed (30 herds), modern dairy system with total mixed ration (TMR) that included silage as a large proportion of the diet (9 herds), and modern dairy system with silage-free TMR (17 herds). Milk samples were analyzed for milk composition and coagulation properties, and parameters were modeled using curd firmness measures (CFt) collected every 15 s from a lacto-dynamographic analysis of 90 min. When compared with traditional milk coagulation properties (MCP), the curd firming measures showed greater variability and yielded a more accurate description of the milk coagulation process: the model converged for 93.1% of the milk samples, allowing estimation of 4 CFt parameters and 2 derived traits [maximum CF (CF(max)) and time from rennet addition to CF(max) (t(max))] for each sample. The milk samples whose CFt equations did not converge showed longer rennet coagulation times obtained from the model (RCT(eq)) and higher somatic cell score, and came from less-productive cows. Among the sources of variation tested for the CFt parameters, dairy herd system yielded the greatest differences for the contrast between the traditional farm and the 3 modern farms, with the latter showing earlier coagulation and greater instant syneresis rate constant (k(SR)). The use of TMR yielded a greater tmax because of a higher instant curd
Henriksson, M; Cederberg, C; Swensson, C
Feed production is a significant source of greenhouse gas (GHG) emissions from dairy production and demands large arable and pasture acreage. This study analysed how regional conditions influence GHG emissions of dairy feed rations in a life cycle perspective, that is the carbon footprint (CF) and the land area required. Factors assessed included regional climate variations, grass/clover silage nutrient quality, feedstuff availability, crop yield and feed losses. Using the Nordic feed evaluation model NorFor, rations were optimised for different phases of lactation, dry and growing periods for older cows, first calvers and heifers by regional feed advisors and combined to annual herd rations. Feed production data at farm level were based on national statistics and studies. CF estimates followed standards for life cycle assessment and used emissions factors provided by IPCC. The functional unit was 'feed consumption to produce 1 kg energy corrected milk (ECM) from a cow with annual milk yield of 9 900 kg ECM including replacement animals and feed losses'. Feed ration CF varied from 417 to 531 g CO2 e/kg ECM. Grass/clover silage contributed more than 50% of total GHG emissions. Use of higher quality silage increased ration CF by up to 5% as a result of an additional cut and increased rates of synthetic N-fertiliser. Domestically produced horse bean (Vicia faba), by-products from the sugar industry and maize silage were included in the rations with the lowest CF, but horse bean significantly increased ration land requirement. Rations required between 1.4 to 2 m2 cropland and 0.1 to 0.2 m2/kg semi-natural grassland per kg ECM and year. Higher yield levels reduced ration total CF. Inclusion of GHG emissions from land use change associated with Brazilian soya feed significantly increased ration CF. Ration CF and land use depended on ration composition, which was highly influenced by the regional availability and production of feedstuffs. The impact of individual
Julián Reyes Vélez
Full Text Available The objectives of this study are to determine the occurrence of antimicrobial resistance (AMR genes using whole-genome sequence (WGS of Streptococcus uberis (S. uberis and Streptococcus dysgalactiae (S. dysgalactiae isolates, recovered from dairy cows in the Canadian Maritime Provinces. A secondary objective included the exploration of the association between phenotypic AMR and the genomic characteristics (genome size, guanine–cytosine content, and occurrence of unique gene sequences. Initially, 91 isolates were sequenced, and of these isolates, 89 were assembled. Furthermore, 16 isolates were excluded due to larger than expected genomic sizes (>2.3 bp × 1,000 bp. In the final analysis, 73 were used with complete WGS and minimum inhibitory concentration records, which were part of the previous phenotypic AMR study, representing 18 dairy herds from the Maritime region of Canada (1. A total of 23 unique AMR gene sequences were found in the bacterial genomes, with a mean number of 8.1 (minimum: 5; maximum: 13 per genome. Overall, there were 10 AMR genes [ANT(6, TEM-127, TEM-163, TEM-89, TEM-95, Linb, Lnub, Ermb, Ermc, and TetS] present only in S. uberis genomes and 2 genes unique (EF-TU and TEM-71 to the S. dysgalactiae genomes; 11 AMR genes [APH(3′, TEM-1, TEM-136, TEM-157, TEM-47, TetM, bl2b, gyrA, parE, phoP, and rpoB] were found in both bacterial species. Two-way tabulations showed association between the phenotypic susceptibility to lincosamides and the presence of linB (P = 0.002 and lnuB (P < 0.001 genes and the between the presence of tetM (P = 0.015 and tetS (P = 0.064 genes and phenotypic resistance to tetracyclines only for the S. uberis isolates. The logistic model showed that the odds of resistance (to any of the phenotypically tested antimicrobials was 4.35 times higher when there were >11 AMR genes present in the genome, compared with <7 AMR genes (P < 0.001. The odds of resistance was lower for S
Mahnani, A; Sadeghi-Sefidmazgi, A; Keshavarzi, H
Stillbirth is an economically important trait on dairy farms. Knowledge of the consequences of, and the economic losses associated with stillbirth can help the producer when making management decisions. The objectives of this study were to determine the effects of stillbirth on productive and reproductive performance as well as financial losses due to stillbirth incidence in Iranian Holstein dairy farms. Economic and performance data were collected from nine Holstein dairy farms in Isfahan and Khorasan provinces of Iran from March 2008 to December 2013. The final data set included 160 410 calving records from 53 265 cows. A linear mixed model was developed to evaluate the effects of stillbirth on performance of primiparous and multiparous cows separately and overall. An economic model was used to estimate the economic losses due to stillbirth. The incidence of stillbirth cases per cow per year was 4.2% on average (3.4% to 6.8% at herd level). The least square means results showed that a case of stillbirth significantly (P0.05). Overall, a case of stillbirth reduced 305-day milk yield by 544.0±76.5 kg/cow per lactation. Stillbirth had no significant effects on 305-day fat and protein percentages in either primiparous or multiparous cows. Overall, cows that gave birth to stillborn calves had significantly increased days open by 14.6±2.6 days and the number of inseminations per conception by 0.2 compared with cows that gave birth to live calves (Pfinancial losses associated with stillbirth incidence averaged US$ 938 per case (range from $US 767 to $US 1189 in the nine investigated farms). The loss of a calf was not the only cost associated with stillbirth, as it accounted for 71.0% of the total cost. The costs of dystocia (7.6%) and culling and replacement expenses (6.3%) were the next most important costs associated with stillbirth. These results can be used to assess the potential return from management strategies to reduce the occurrence of stillbirths.
Andrey Pinzón Trujillo
Full Text Available The purpose of this work was to carry out a study about the effects of subclinical mastitis in cows of 34 dairy farms in the Upper Chicamocha region (Boyacá department.The farms are registered in the livestock farmers association of Boyacá (FABEGAN. This study was done with the aim to know about the infection status of cows and establish which are the principal etiologic agents associated with the disease and its relation with the milking routine. To this aim, applied comparison even tests for the productive variables to relate with the California Mastitis Test (CMT and the microbiological characterization, a blocks design under factorial 2 x 4 array to analyze the existence of significant differences between the mastitis grades, the sample season and its interaction, and blocks design under factorial 2 x 4 array to analyze the existence of significant differences among the mastitis subclinical grades, the sampling season and its interaction. 6616 quarters were submitted to the California Mastitis Test (CMT in two times and different season. The results did not show any significant differences between the two times of sampling. The positive samples according with CMT (CMT-2 and CMT-3 were submitted to microbiological tests where, in the most of the cases of mastitis, the presence of Streptococcus agalactiae and Staphylococcus aureus was detected. They are the main etiologic agents in the disease. The results indicate the close relation between the milking routine and mastitis. The deficient practices in the milking process are the cause of dissemination and prevalence of mastitis in farms.
Hospido, Almudena; Sonesson, Ulf
Mastitis is defined as an inflammatory reaction of udder tissue to bacterial, chemical, thermal or mechanical injury, which causes heavy financial losses and milk wastage throughout the world. Until now, studies have focused on the economic aspects from which perspective mastitis can generally be considered as the most serious disease in dairy cows; however, costs are not the only negative consequence resulting from the infection. The environmental impact is also significant; milk is discarded, which means lower efficiency and hence a greater environmental impact per produced liter of milk. Less milk is produced, which leads to an increased need for calf feed, and meat production is also affected. The main aim of this paper was to quantify the environmental impact of mastitis incidence. A standard scenario (representative of present-day reality in Galicia, Spain) and an improved scenario (in which mastitis incidence rate is reduced by diverse actions) have been defined and compared using Life Cycle Assessment (LCA) methodology. Among the impact categories studied, acidification, eutrophication and global warming were found to be the most significant environmental impacts. In all these categories, it was revealed that a decrease in mastitis incidence has a positive influence as the environmental impact is reduced. Even if the quantitative results cannot show a considerable decrease in the environmental burden, the impact cannot be regarded as negligible when the total consumption or total production of a region is considered. For example, the outcome of the proposed improvement measures for Spain's greenhouse gas emissions can be quantified as 0.06% of total emissions and 0.56% of emissions by the agricultural sector
Hospido, Almudena; Sonesson, Ulf
Mastitis is defined as an inflammatory reaction of udder tissue to bacterial, chemical, thermal or mechanical injury, which causes heavy financial losses and milk wastage throughout the world. Until now, studies have focused on the economic aspects from which perspective mastitis can generally be considered as the most serious disease in dairy cows; however, costs are not the only negative consequence resulting from the infection. The environmental impact is also significant; milk is discarded, which means lower efficiency and hence a greater environmental impact per produced liter of milk. Less milk is produced, which leads to an increased need for calf feed, and meat production is also affected. The main aim of this paper was to quantify the environmental impact of mastitis incidence. A standard scenario (representative of present-day reality in Galicia, Spain) and an improved scenario (in which mastitis incidence rate is reduced by diverse actions) have been defined and compared using Life Cycle Assessment (LCA) methodology. Among the impact categories studied, acidification, eutrophication and global warming were found to be the most significant environmental impacts. In all these categories, it was revealed that a decrease in mastitis incidence has a positive influence as the environmental impact is reduced. Even if the quantitative results cannot show a considerable decrease in the environmental burden, the impact cannot be regarded as negligible when the total consumption or total production of a region is considered. For example, the outcome of the proposed improvement measures for Spain's greenhouse gas emissions can be quantified as 0.06% of total emissions and 0.56% of emissions by the agricultural sector.
Hospido, Almudena [Department of Chemical Engineering, Institute of Technology, University of Santiago de Compostela, 15782 Santiago de Compostela (Spain)]. E-mail: firstname.lastname@example.org; Sonesson, Ulf [Swedish Institute for Food and Biotechnology (SIK), PO Box 5401, SE-402 29 Goeteborg (Sweden)
Mastitis is defined as an inflammatory reaction of udder tissue to bacterial, chemical, thermal or mechanical injury, which causes heavy financial losses and milk wastage throughout the world. Until now, studies have focused on the economic aspects from which perspective mastitis can generally be considered as the most serious disease in dairy cows; however, costs are not the only negative consequence resulting from the infection. The environmental impact is also significant; milk is discarded, which means lower efficiency and hence a greater environmental impact per produced liter of milk. Less milk is produced, which leads to an increased need for calf feed, and meat production is also affected. The main aim of this paper was to quantify the environmental impact of mastitis incidence. A standard scenario (representative of present-day reality in Galicia, Spain) and an improved scenario (in which mastitis incidence rate is reduced by diverse actions) have been defined and compared using Life Cycle Assessment (LCA) methodology. Among the impact categories studied, acidification, eutrophication and global warming were found to be the most significant environmental impacts. In all these categories, it was revealed that a decrease in mastitis incidence has a positive influence as the environmental impact is reduced. Even if the quantitative results cannot show a considerable decrease in the environmental burden, the impact cannot be regarded as negligible when the total consumption or total production of a region is considered. For example, the outcome of the proposed improvement measures for Spain's greenhouse gas emissions can be quantified as 0.06% of total emissions and 0.56% of emissions by the agricultural sector.
Testa, Francesco; Marano, Giuseppe; Ambrogi, Federico; Boracchi, Patrizia; Casula, Antonio; Biganzoli, Elia; Moroni, Paolo
Elevated bulk tank milk somatic cell count (BMSCC) has a negative impact on milk production, milk quality, and animal health. Seasonal increases in herd level somatic cell count (SCC) are commonly associated with elevated environmental temperature and humidity. The Temperature Humidity Index (THI) has been developed to measure general environmental stress in dairy cattle; however, additional work is needed to determine a specific effect of the heat stress index on herd-level SCC. Generalized Additive Model methods were used for a flexible exploration of the relationships between daily temperature, relative humidity, and bulk milk somatic cell count. The data consist of BMSCC and meteorological recordings collected between March 2009 and October 2011 of 10 dairy farms. The results indicate that, an average increase of 0.16% of BMSCC is expected for an increase of 1°C degree of temperature. A complex relationship was found for relative humidity. For example, increase of 0.099%, 0.037% and 0.020% are expected in correspondence to an increase of relative humidity from 50% to 51%, 80% to 81%; and 90% to 91%, respectively. Using this model, it will be possible to provide evidence-based advice to dairy farmers for the use of THI control charts created on the basis of our statistical model. Copyright © 2017 Elsevier Ltd. All rights reserved.
Slavica Golc Teger
Full Text Available Factors affecting the freezing point of milk in a herd of 200 Black and White cows with the average milk yield of 8 386 kg in the lactation and 8 328 kg in the standard lactation were examinated. Over the period of one year (2002 and based upon 1 773 individual monthly collected milk samples with the average contents of 3.91% fat, 3.26% protein, 4.54% lactose, 33.4 mg/100 ml urea and 331000 somatic cells per ml in milk were determined. The average freezing point of milk (n = 1 680 was estimated to be –0.527 ºC, with a range from -0.562 ºC to -0.423 ºC. In 210 (12.5% samples was higher than -0.515 ºC. The lowest freezing point (-0.532 ºC was found in the samples collected in the first month after calving and highest (-0.522 ºC in the samples of 12th month of lactation. The differences between the freezing point of milk after the first and the second calving (-0.530 ºC; P < 0.05 and those after the fifth calving (-0.523 ºC; P < 0.05 were also significant. The samples collected in month from January to April (-0.538 ºC to -0.532 ºC were significantly lower in comparison to samples collected in May and June (-0.517 ºC and -0.519 ºC. The following statistically significant correlation coefficients between cows' properties, milk composition and the freezing point of milk were found: month of lactation r = 0.233 (P < 0.001; lactation number r = 0.196 (P < 0.001; age of cows (years r = 0.231 (P < 0.001; month of the year r = 0.0253 (P < 0.001; milk yield per milking day r = -0.106 (P < 0.001; fat corrected milk content (FCM per milking day r = -0.234 (P < 0.001; lactose % r = -0.530 (P < 0.001; fat % r = -0.351 (P < 0.001; protein % r = 0.058 (P < 0.05; urea mg/100 mL r = 0.091 (P < 0.001 and somatic cell count r = 0.154 (P < 0.001. The sum of effects (month of the year, lactation lenght and fat, protein and lactose content of milk was found to account for about 70% variability of the total depression of milk freezing point (R2 = 0.698.
Nielsen, Liza Rosenbaum; Kudahl, Anne Braad; Østergaard, Søren
of the six age-groups; 2) S. Dublin incidence and number of animals in each infection state; and 3) S. Dublin related morbidity and mortality in the acutely infected animals. The effects of introducing one infectious heifer on the risk of spread of S. Dublin within the herd and on the duration of infection...... for the individual animals in each of the six age groups in the herd. The hygiene level was highly influential on the probability that the infection spread within the herd, duration of infection and epidemic size. The herd susceptibility level was also influential, but not likely to provide sufficient prevention...... the probability of extinction. In general, disease and mortality patterns followed epidemic waves in the herds. However, an interesting pattern was seen for acute infections and abortions in adult cattle after the first 2 years of infection in herds with poor hygiene and high susceptibility. Repeated infections...
Nielsen, Torben Dahl; Vesterbæk, Inge Langborg; Kudahl, Anne Braad
statistical methods: logistic regression analysis and discriminant analysis. Both analyses identified that increased probability of successful control was strongly associated with avoiding purchase of cattle from test-positive herds. Additionally, ensuring good calving area management, separating calf pens......, by only letting one person be responsible for colostrum management and by not feeding poorer quality colostrum to bull calves than to heifer calves. The results are useful for dairy cattle producers and veterinary authorities to substantiate advice on management practices that are likely to lead......Studies reporting on how to control Salmonella in cattle herds have mainly been theoretical simulation models or case reports describing control of clinical salmonellosis outbreaks. The objective of this observational study was to investigate which management routines were associated...
Katholm, Jørgen; Bennedsgaard, T.W.; Koskinen, M.T.
Results of a commercial real-time PCR analysis for 11 mastitis pathogens from bulk tank milk (BTM) samples from all 4,258 Danish dairy herds in November 2009 to January 2010 were compared with somatic cell count (SCC) and total bacteria count (TBC) estimates in BTM. For Streptococcus agalactiae......, Streptococcus dysgalactiae, and Streptococcus uberis, a low real-time PCR cycle threshold (Ct) value (corresponding to high bacterial DNA quantity) was correlated with higher SCC and higher TBC. For Staphylococcus aureus, low Ct values were correlated only with higher SCC. For the environmental mastitis...... pathogens Klebsiella spp., Enterococcus spp., and Escherichia coli, low Ct values had a correlation with higher TBC. Staphylococcus spp. were found in the BTM from all herds, Strep. uberis in 95%, Staph. aureus in 91%, and Strep. dysgalactiae in 86%, whereas E. coli, Klebsiella, and Strep. agalactiae were...
Wareth, Gamal; Melzer, Falk; Böttcher, Denny; El-Diasty, Mohamed; El-Beskawy, Mohamed; Rasheed, Nesma; Schmoock, Gernot; Roesler, Uwe; Sprague, Lisa D; Neubauer, Heinrich
Bovine brucellosis is endemic in Egypt in spite of application of surveillance and control measures. An increase of abortions was reported in a Holstein dairy cattle herd with 600 animals in Damietta governorate in Egypt after immunisation with Brucella (B.) abortus RB51 vaccine. Twenty one (10.6%) of 197 vaccinated cows aborted after 3 months. All aborted cows had been tested seronegative for brucellosis in the past 3 years. B. abortus was isolated from four foetuses. Conventional biochemical and bacteriological identification and polymerase chain reaction (PCR) confirmed two B. abortus biovar (bv.) 1 smooth and two B. abortus rough strains. None of the B. abortus isolates were identified as RB51. Genotyping analysis by multiple locus of variable number tandem repeats analysis based on 16 markers (MLVA-16) revealed two different profiles with low genetic diversity. B. abortus bv1 was introduced in the herd and caused abortions. Copyright © 2016 Elsevier B.V. All rights reserved.
Yakobson, Boris; Taylor, Nick; Dveres, Nelli; Rozenblut, Shira; Tov, Boris Even; Markos, Majid; Gallon, Nadav; Homer, David; Maki, Joanne
In contrast to many regions of the world where rabies is endemic in terrestrial wildlife species, wildlife rabies has been controlled in Israel by oral rabies vaccination programs, but canine rabies is re-emerging in the northern area of the Golan Heights. From 2009 to 2014 there were 208 animal rabies cases in Israel; 96 (46%) were considered introduced primary cases in dogs, triggering 112 secondary cases. One third (37/112) of the secondary cases were in cattle. Rabies vaccination is voluntary for cattle in Israel, except those on public exhibit. Rabies vaccination schedules for cattle vary based on farm practices and perception of risk. In this study 59 cattle from a dairy farm which routinely vaccinates against rabies were assigned into six groups according to age and vaccination histories. Four groups contained adult cows which had received one previous rabies vaccination, one group of adults had received two previous vaccinations, and one group was unvaccinated calves. Serum samples were collected and the cows were vaccinated with a commercial rabies vaccine. Sera were again collected 39 days later and the calf group re-vaccinated and re-sampled 18 days later. Sera were analyzed for the presence of rabies virus neutralizing antibodies using the rapid immunofluorescent antibody test. Cattle with antibody titres ≥ 0.5 IU/ml were considered to be protected against rabies. Twenty-six of 27 adult cattle (96%) vaccinated once at less than five months old did not have protective titres. Sixty percent (6/10) cattle vaccinated once at around six months of age did have adequate titres. Cattle previously vaccinated twice (n=10; 100%) with an 18 month interval between inoculations, had protective titres and protective antibody titres following booster vaccination (n=51; 100%). The anamnestic response of cattle to a killed rabies vaccine was not affected by the time interval between vaccinations, which ranged from 12 to 36 months. These results suggest that calves from
Denis-Robichaud, J; Cerri, R L A; Jones-Bitton, A; LeBlanc, S J
Identifying cows in estrus remains a challenge on dairy cattle farms, and tools and technologies have been developed and used to complement or replace visual detection of estrus. Automated activity monitoring (AAM) systems and timed artificial insemination (TAI) are technologies available to dairy farmers, but many factors can influence their relative performance. The objective of the present study was to compare reproductive performance of cows managed with an AAM system combined with TAI, or with a TAI program (Double Ovsynch) for insemination before 88 DIM. From April 2014 to April 2015, 998 cows from 2 herds were randomly assigned either to be inseminated at 85 ± 3 DIM exclusively using the Double Ovsynch protocol for TAI, or to be inseminated based on estrus detection by AAM without hormonal intervention between 50 and 75 DIM; if no alarm was detected by 75 DIM, cows were inseminated following the single Ovsynch protocol (AAM + Ovsynch). The herds used different AAM systems. Parity, hyperketonemia at wk 1 and 2 postpartum (PP), purulent vaginal discharge at wk 5 PP, body condition score at wk 7 PP, and anovulation to wk 9 PP were recorded. These health indicators did not significantly differ between treatments, but did between herds. The effect of treatment on pregnancy at first insemination and by 88 DIM were assessed using logistic regression models. Time to pregnancy was assessed using survival analysis. Results are reported from intention-to-treat analyses. Treatment did not affect pregnancy at first insemination or pregnancy by 88 DIM, but we found significant interactions between treatment and herd for both outcomes. In herd 2, marginal mean pregnancy at first AI was greater with Double Ovsynch (38%) than AAM + Ovsynch (31%), but no difference was observed in herd 1 (Double Ovsynch = 31%; AAM + Ovsynch = 34%). By 88 DIM, a smaller proportion of cows in herd 1 were pregnant in Double Ovsynch (31%) than AAM + Ovsynch (49%), but there was no difference in
Khol, J L; Wassertheurer, M; Sodoma, E; Revilla-Fernández, S; Damoser, J; Osterreicher, E; Dünser, M; Kleb, U; Baumgartner, W
Mycobacterium avium ssp. paratuberculosis (MAP) causes Johne's disease (JD) in ruminants and is shed into the milk of infected cows, which contributes to the controversial discussion about a possible link between MAP and Crohn's disease in humans. The aim of the study was to investigate the risk for the entry of MAP in the food chain via milk from dairy farms with subclinical JD. Therefore, the occurrence of MAP in the milk of a dairy herd with a low prevalence of JD was studied in single and bulk tank milk samples over a period of 23 mo and compared with MAP shedding into feces. Milk, fecal, and blood samples were taken from all cows older than 1.5 yr of age at the beginning and the end of the trial and analyzed for MAP or specific antibodies. In addition, 63 cows (33 MAP infected and 30 MAP noninfected) were selected for monthly sampling. Raw and pasteurized bulk tank milk samples were collected on a monthly basis. The milk samples were tested for MAP by real-time quantitative PCR (qPCR), and the fecal samples were tested for bacterial shedding by qPCR or solid culture. Based on the results of the herd investigations, the prevalence of cows shedding MAP was around 5%; no cases of clinical JD were observed during the study period. The results of the ELISA showed high variation, with 2.1 to 5.1% positive milk samples and 14.9 to 18.8% ELISA-positive blood samples. Monthly milk sampling revealed low levels of MAP shedding into the individual milk samples of both MAP-infected and noninfected cows, with only 13 cows shedding the bacterium into milk during the study period. Mycobacterium avium ssp. paratuberculosis was not detected by qPCR in any raw or pasteurized bulk tank milk sample throughout the study. A significant positive association could be found between MAP shedding into milk and feces. From the results of the present study, it can be concluded that MAP is only shed via milk in a small proportion of cows with subclinical JD for a limited period of time and
Luini, M; Cremonesi, P; Magro, G; Bianchini, V; Minozzi, G; Castiglioni, B; Piccinini, R
Staphylococcus aureus is one of the most common mastitis-causing pathogens worldwide. In the last decade, livestock-associated methicillin-resistant S. aureus (LA-MRSA) infections have been described in several species, included the bovines. Hence, this paper investigates the diffusion of MRSA within Italian dairy herds; the strains were further characterized using a DNA microarray, which detects 330 different sequences, including the methicillin-resistance genes mecA and mecC and SCCmec typing. The analysis of overall patterns allows the assignment to Clonal Complexes (CC). Overall 163 S. aureus isolates, collected from quarter milk samples in 61 herds, were tested. MRSA strains were further processed using spa typing. Fifteen strains (9.2%), isolated in 9 herds (14.75%), carried mecA, but none harboured mecC. MRSA detection was significantly associated (P<0.011) with a within-herd prevalence of S. aureus intra-mammary infections (IMI) ≤5%. Ten MRSA strains were assigned to CC398, the remaining ones to CC97 (n=2), CC1 (n=2) or CC8 (n=1). In 3 herds, MRSA and MSSA co-existed: CC97-MRSA with CC398-MSSA, CC1-MRSA with CC8-MSSA and CC398-MRSA with CC126-MSSA. The results of spa typing showed an overall similar profile of the strains belonging to the same CC: t127-CC1, t1730-CC97, t899 in 8 out of 10 CC398. In the remaining 2 isolates a new spa type, t14644, was identified. The single CC8 was a t3092. The SCCmec cassettes were classified as type IV, type V or type IV/V composite. All or most strains harboured the genes encoding the β-lactamase operon and the tetracycline resistance. Streptogramin resistance gene was related to CC398. Enterotoxin and leukocidin genes were carried only by CC1, CC8 and CC97-MRSA. The persistence of MRSA clones characterized by broader host range, in epidemiologically unrelated areas and in dairy herds with low prevalence of S. aureus IMI, might enhance the risk for adaptation to human species. Copyright © 2015 Elsevier B.V. All rights
Romero, J.J.; Breda, van S.; Vargas, B.; Dolz, G.; Frankena, K.
A cross-sectional study was conducted to assess the effect of neosporosis on productive and reproductive parameters in dairy cows. Cows (n = 2743) from 94 farms located in the most important dairy areas in Costa Rica were used in the study. The size of the herds ranged from 32 to 379 females (mean =
Van den Brom, R; Santman-Berends, I; Luttikholt, S; Moll, L; Van Engelen, E; Vellema, P
In the period from 2005 to 2009, Coxiella burnetii was a cause of abortion waves at 28 dairy goat farms and 2 dairy sheep farms in the Netherlands. Two years after the first abortion waves, a large human Q fever outbreak started mainly in the same region, and aborting small ruminants were regarded as most probable source. To distinguish between infected and noninfected herds, a surveillance program started in October 2009, based on PCR testing of bulk tank milk (BTM) samples, which had never been described before. The aim of this study was to analyze the effectiveness of this surveillance program and to evaluate both the effect of culling of pregnant dairy goats on positive farms and of vaccination on BTM results. Bulk tank milk samples were tested for C. burnetii DNA using a real-time PCR, and results were analyzed in relation to vaccination, culling, and notifiable (officially reported to government) C. burnetii abortion records. In spring and autumn, BTM samples were also tested for antibodies using an ELISA, and results were evaluated in relation to the compulsory vaccination campaign. Between October 2009 and April 2014, 1,660 (5.6%) out of 29,875 BTM samples from 401 dairy goat farms tested positive for C. burnetii DNA. The percentage of positive samples dropped from 20.5% in 2009 to 0.3% in 2014. In a multivariable model, significantly higher odds of being PCR positive in the BTM surveillance program were found in farms of which all pregnant dairy goats were culled. Additionally, the risk for C. burnetii BTM PCR positivity significantly decreased after multiple vaccinations. Bulk tank milk ELISA results were significantly higher after vaccination than before. The ELISA results were higher after multiple vaccinations compared with a single vaccination, and ELISA results on officially declared infected farms were significantly higher compared with noninfected farms. In conclusion, BTM surveillance is an effective and useful tool to detect C. burnetii shedding
Tatone, Elise H; Duffield, Todd F; LeBlanc, Stephen J; DeVries, Trevor J; Gordon, Jessica L
An observational study of 790 to over 3,000 herds was conducted to estimate the within-herd prevalence and cow-level risk factors for ketosis in dairy cattle in herds that participate in a Dairy Herd Improvement Association (DHIA) program. Ketosis or hyperketolactia (KET) was diagnosed as milk β-hydroxybutyrate ≥0.15 mmol/L at first DHIA test when tested within the first 30 d in milk. Seven hundred ninety-five herds providing at least 61 first milk tests from June 2014 to December 2015 were used to estimate the provincial within-herd prevalence of KET. All herds on DHIA in Ontario (n = 3,042) were used to construct cow-level multilevel logistic regression models to investigate the association of DHIA collected variables with the odds of KET at first DHIA milk test. Primiparous and multiparous animals were modeled independently. The cow-level KET prevalence in Ontario was 21%, with an average within-herd prevalence of 21% (standard deviation = 10.6) for dairy herds enrolled in a DHIA program. The prevalence of KET had a distinct seasonality with the lowest prevalence occurring from July to November. Automatic milking systems (AMS) were associated with increased within-herd prevalence, as well as increased odds of KET in multiparous animals at first test (odds ratio: 1.45; 95% confidence interval: 1.30 to 1.63). Jersey cattle had over 1.46 times higher odds of KET than Holstein cattle. Milk fat yield ≥1.12 kg/d at the last test of the previous lactation was associated with decreased odds of KET in the current lactation (odds ratio: 0.56; 95% confidence interval: 0.53 to 0.59). Increased days dry and longer calving intervals, for multiparous animals, and older age at first calving for primiparous animals increased the odds of KET at first test. This study confirms previous findings that increased days dry, longer calving intervals, and increased age at first calving are associated with increased odds of KET and is the first report of increased KET in herds with
Jensen, Anette Møllegaard; Bjorkman, C.; Kjeldsen, A.M.
%. The prevalence and distribution of seropositivity, gestation number prior to sampling, and breed were related to abortions and perinatal deaths using a random-effects logistic-regression model. Abortion risk was significantly increased in seropositive animals (OR=3) and in greater than or equal to 2nd......-gestation cows (OR=3). Perinatal death was significantly influenced by gestation number and breed, but not by serostatus, Reproductive performance and culling risk of cows were not affected by serostatus. Seropositivity increased with "age" (i.e, gestation number) (P=0.02). In open cows, seropositivity tended...
Cortimiglia, C; Luini, M; Bianchini, V; Marzagalli, L; Vezzoli, F; Avisani, D; Bertoletti, M; Ianzano, A; Franco, A; Battisti, A
Staphylococcus aureus is the most important causative agent of subclinical mastitis in cattle resulting in reduced milk production and quality. Methicillin-resistant S. aureus (MRSA) strains has a clear zoonotic relevance, especially in the case of occupational exposure. The aim of the study was to evaluate the prevalence of S. aureus and MRSA in bulk tank milk (BTM) from dairy cattle herds in the Lombardy Region (Northern Italy) and to identify the main MRSA circulating genotypes. MRSA strains were characterized by susceptibility testing, multi-locus sequence typing (MLST), spa typing and SCCmec typing. A total 844 BTM samples were analysed and S. aureus and MRSA were detected in 47·2% and 3·8% of dairy herds, respectively. MLST showed that the majority (28/32) of isolates belonged to the typical livestock-associated lineages: ST398, ST97 and ST1. Interestingly, in this study we report for the first time the new ST3211, a single locus variant of ST(CC)22, with the newly described 462 aroE allele. Our study indicates high diffusion of S. aureus mastitis and low, but not negligible, prevalence of MRSA in the considered area, suggesting the need for planning specific control programmes for bovine mastitis caused by S. aureus, especially when MRSA is implicated.
Full Text Available Aim: Monitoring was performed in order to determine the Selenium (Se status of cattle herds in different agricultural areas in Wallonia (Belgium. Materials and Methods: The study included 114 heifers and 184 cows (82 dairy and 102 beef cows from 66 cattle farms situated in Wallonia. The Se status was assessed by measuring the glutathion peroxydase in red cells and converting it to the equivalent Se blood content. Results: The average blood concentrations of Se were very low. The Ardennes region was an area where the lowest Se status was recorded. The highest levels of Se in dairy cows and beef cows were recorded respectively in the limoneuse region and Famenne areas. The Se content in beef herds was lower compared with that of dairy herds (35 vs. 56 μg/L, p<0.01. Conclusion: On average over all the regions, 87% of animals were classified as deficient and only 13% of the animals were classified as adequate. The heifers from both dairy and beef herds in Wallonia exhibited a deficiency in Se classified as moderate to severe. The beef herds showed larger deficiencies compared with the dairy herds. Selenium deficiency can be prevented by ensuring adequate supplementation of deficient animals in Se deficient regions. An increased consumption of vitamin-mineral supplements, the use of Se-enriched fertilizers and ingredients containing high levels of Se can help to reduce or correct deficiencies recorded in cattle herds in Wallonia.
Jan 11, 2017 ... first artificial insemination (MG1; n = 62 dairy cows), cows presenting clinical mastitis between the first artificial insemination ... study clearly indicate that, clinical mastitis decreases reproductive performance of dairy cows. Key words: ... shift towards higher production per animal, inadequate nutrition, poor ...
Carneiro, Luisa Cunha; Ferreira, Adolfo Firmo; Padua, Mariana; Saut, João Paulo; Ferraudo, Antonio Sergio; Dos Santos, Ricarda Maria
In dairy cattle, uterine infections are not life threatening and often unavoidable; however, they reduce fertility and increase the production costs of properties. The aim of this study was to evaluate the incidence of subclinical endometritis from 32 to 70 days in milk (DIM) and its effects on the reproductive performance of crossbred dairy cows. Lactating cows (Holstein/Gir; n = 172), with no history of retained placenta, without clinical signs of uterine infection were used. The body condition score (BCS) was evaluated on a scale from 1 to 5. Ultrasound examination was performed to evaluate uterine lining and ovarian activity, while vaginal mucus was analyzed by gloved hand. The diagnosis of subclinical endometritis was performed by endometrial cytobrush technique. The samples were collected, stained, and examined microscopically; positive cases for subclinical endometritis were considered with the presence of ≥5 % of neutrophils. Later, the cows were submitted to conventional artificial insemination or timed artificial insemination. The incidence of subclinical endometritis in the herd was 26 %, and this was not affected by the season of calving, presence of corpus luteum, DIM, and parity. Cows with a BCS ≤2.50 had a higher incidence of subclinical endometritis. The conception rate to first insemination and pregnancy rate at 150 days postpartum were not influenced by the presence of subclinical endometritis in crossbred dairy cows.
Hagnestam-Nielsen, Christel; Østergaard, Søren
reflects the fact that in different stages of lactation, CM gives rise to different yield-loss patterns or postulates just one type of yield-loss pattern irrespective of when, during lactation, CM occurs. A dynamic and stochastic simulation model, SimHerd, was used to study the effects of CM in a herd...... a single yield-loss pattern irrespective of when, during the lactation period, the cow develops CM - was compared with a new modelling strategy in which CM was assumed to affect production differently depending on its lactational timing. The effect of the choice of reference level when estimating yield...
Shiferaw, Y; Tenhagen, B A; Bekana, M; Kassa, T
The study was conducted to examine the fertility status of crossbred dairy cows in mixed crop-livestock production (MCLP), market-oriented specialized dairy production (MSDP) and urban dairy production (UDP) systems, including the Holetta Agricultural Research Center (HARC). Data on general farm management variables and reproductive histories were collected from study farms by questionnaire and from individual cow records. Age at first service and age at first calving were 29.58 months (n = 424) and 40.6 months (n = 348), respectively. Cows managed under UDP were younger at first service and at first calving (p<0.05). The mean intervals from calving to first service and to conception were 141.98 days (n = 284) and 185.02 days (n = 219), respectively. The mean calving interval for cows was 551.82 days (n = 258). Cows in MCLP had longer intervals from calving to first service and to conception and longer calving intervals than those managed under MSDP, UDP and HARC. First service conception rate (43.42%), number of services per conception (1.75) and pregnancy rate (79.29%) did not differ significantly between production systems. Reproductive performance was best in UDP followed by HARC and MSDP. The difference between MCLP and the rest points to particular difficulties in that system. To improve reproductive performance and economic benefit, there should be conservative stocking rate, sensible year-round feeding, a herd health plan, and sustainable extension service.
Giuliodori, M J; Magnasco, R P; Becu-Villalobos, D; Lacau-Mengido, I M; Risco, C A; de la Sota, R L
The objectives of this study were to assess the risk factors for metritis, its effects on milk yield and on reproductive performance, and the efficacy of ceftiofur therapy in Holstein dairy cows. Cows (n=303) from a commercial dairy herd in Argentina were studied. Cows were scored for body condition, and blood samples were collected on d -14, 7, 21, 31, 41, and 50 relative to parturition. Cows having a watery, purulent, or brown, and fetid vaginal discharge (VD) and rectal temperature ≤ 39.2°C were diagnosed as having clinical metritis, and those having a similar VD and rectal temperature >39.2°C were diagnosed as having puerperal metritis. Both clinical and puerperal metritis cows were randomly assigned to control (no treatment) or ceftiofur group (2.2mg/kg×3 consecutive days). Cure was declared if clear VD was observed at 21 d in milk (DIM). Blood samples were analyzed for nonesterified fatty acids, β-hydroxybutyrate, and blood urea nitrogen using commercial kits, and for insulin-like growth factor-1, insulin, and leptin by RIA. Data were analyzed with PROC MIXED, GENMOD, PHREG, and LIFETEST from SAS (SAS Institute Inc., Cary, NC). The risk for metritis increased with dystocia, retained fetal membranes, and dead calf [AOR (adjusted odds ratio)=2.58, 95% CI: 1.189-5.559], and as prepartum nonesterified fatty acids levels increased (AOR=1.001, 95% CI: 0.999-1.002). Conversely, risk decreased as prepartum insulin-like growth factor-1 increased (AOR=0.65, 95% CI: 0.349-1.219). Cows having either clinical or puerperal metritis produced less milk by 90 DIM than did healthy cows (2,236 ± 172 vs. 2,367 ± 77 vs. 2,647 ± 82 kg, respectively). Cows with puerperal metritis had lower risk for pregnancy by 100 DIM (AOR=0.189, 95% CI: 0.070-0.479) and a lower hazard rate for pregnancy by 150 DIM (hazard rate: 0.753, 95% CI: 0.621-0.911), and took longer to get pregnant (129 vs. 111 vs. 109 d, for puerperal metritis, clinical metritis, and healthy cows, respectively
Marcos Aurélio Lopes
Full Text Available Conduziu-se esta pesquisa com o objetivo de avaliar e quantificar o impacto econômico do intervalo de partos em rebanhos de gado de leite. Foram simulados, no software Dimensionamento e Evolução de Rebanhos Bovinos, três rebanhos bovinos leiteiros, de um sistema de produção hipotético composto por 25 fêmeas, da raça holandesa, com média de produção diária de 15 kg, com idade ao primeiro parto de 30 meses, mantidas em 200 ha cultivados com pastagem de Brachiaria decumbens Stapf. com capacidade de suporte de 1UA/ha/ano. A equivalência entre as categorias animais utilizadas foram: matrizes 1,30; fêmeas de 0 - 1 ano 0,30; fêmea de 1-2 anos 0,71; fêmeas de 2-3 anos 1,01 UA/ha. Os três rebanhos possuiam as mesmas taxas de descarte (20% e mortalidade (3% de 0 a 1 ano; 2% de a 1 a 2 anos e 1% de 2 a 3 anos diferindo apenas as taxas de natalidade, quais sejam 100; 80 e 60%, para os casos 1; 2 e 3, respectivamente refletindo em intervalos de partos de 365, 510 e 657 dias. A simulação do impacto econômico foi realizada no aplicativo MS Excel®. O intervalo de partos, afetou diretamente a composição e a evolução do rebanho e influenciou a rentabilidade da atividade leiteira, sendo mais eficiente o índice de natalidade 100%, ou seja, intervalo de partos de 12 meses.The aim of this study was to quantify and evaluate the economic impact of calving interval on dairy herd. A simulation using a Dimensioning and Evolution of Bovine Herd software was conducted on three dairy herds from a hypothetical production system composed by 25 females of Holstein breed, having an average of 15 kg daily milk production, at an age of 30 months after the first calving, kept in a 200 ha Brachiaria decumbens Stapf. pasture presenting an 1AU/ha/year support capacity. The equivalence among the tested animal categories were: dam cows 1.30; females of 0-1 year 0.30; females of 1-2 years 0.71; females of 2-3 years 1.01n AU/ha. The three herds showed the same
Vlkova, H; Babak, V; Vrtkova, I; Cervinkova, D; Marosevic, D; Moravkova, M; Jaglic, Z
The aim of the present work was to examine a dairy herd with an anamnesis of recurrent clinical mastitis and decreased milk production. A total of 239 individual cow milk samples originating from asymptomatic cows were collected at four-month intervals and examined mainly for the presence of Staphylococcus aureus and mastitis streptococci using standard cultivation methods. In total, 29.7% and 9.2% samples were positive for S. aureus and mastitis streptococci, respectively. Unlike for mastitis streptococci, the prevalence of animals positive for S. aureus had an increasing trend (pmastitis, reproductive and periparturient disorders and administration of antibiotics. In contrast to S. aureus, the occurrence of mastitis streptococci in milk was linked with previous cases of clinical mastitis and intramammary administration of antibiotics.
Arendonk, van J.A.M.
Profit equations or functions that reflect the realized profitability of cows have been used in the literature to determine the relative importance of different variables such as milk yield and herd life. In all profit equations, the opportunity cost of postponed replacement, which reflects the
Sørensen, J.T.; Enevoldsen, Carsten; Kristensen, T.
exhibited two different rates of voluntary culling for reproductive failure and milk production, and the feeding regimes consisted of grass silage ad lib. and either 8 or 12 kg of concentrates/day in the first 24 weeks of lactation. The economic result was studied under a herd size and a milk quota...
Raspanti, Claudia G; Bonetto, Cesar C; Vissio, Claudina; Pellegrino, Matías S; Reinoso, Elina B; Dieser, Silvana A; Bogni, Cristina I; Larriestra, Alejandro J; Odierno, Liliana M
Coagulase-negative staphylococci (CNS) are a common cause of bovine subclinical mastitis (SCM). The prevalence of CNS species causing SCM identified by genotyping varies among countries. Overall, the antimicrobial resistance in this group of organisms is increasing worldwide; however, little information exists about a CNS species resistant to antibiotics. The aim of the present study was to genotypically characterize CNS at species level and to determine the prevalence and antibiotic resistance profiles of CNS species isolated from bovine SCM in 51 dairy herds located in the central region of the province of Cordoba, Argentina. In this study, we identified 219 CNS isolates at species level by PCR-restriction fragment length polymorphism of the groEL gene. Staphylococcus chromogenes (46.6%) and Staphylococcus haemolyticus (32%) were the most prevalent species. A minimum of three different CNS species were present in 41.2% of the herds. S. chromogenes was isolated from most of the herds (86.3%), whereas S. haemolyticus was isolated from 66.7% of them. The broth microdilution method was used to test in vitro antimicrobial susceptibility. Resistance to a single compound or two related compounds was expressed in 43.8% of the isolates. S. chromogenes and S. haemolyticus showed a very high proportion of isolates resistant to penicillin. Resistance to two or more non-related antimicrobials was found in 30.6% of all CNS. S. haemolyticus exhibited a higher frequency of resistance to two or more non-related antimicrobials than S. chromogenes. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.
Schaffer, Aaron P; Larson, Robert L; Cernicchiaro, Natalia; Hanzlicek, Gregg A; Bartle, Steven J; Thomson, Daniel U
OBJECTIVE To describe the frequency of calfhood producer-identified bovine respiratory disease complex (BRDC) in Holstein replacement heifers on 1 large farm and determine associations between development of BRDC at ≤ 120 days of age (BRDC120) with milk production estimate, calving interval, and risk of departure from the herd (DFH). DESIGN Retrospective, observational study. ANIMALS 14,024 Holstein heifer calves born on 1 farm. PROCEDURES Data were obtained from herd management records. Cox proportional hazard and generalized linear mixed-effects models were used to assess associations for variables of interest (BRDC120 status, demographic data, and management factors) with DFH, milk production estimate, and calving interval. RESULTS Except for the year 2007, animals identified as having BRDC120 were 1.62 to 4.98 times as likely to leave the herd before first calving, compared with those that did not have this designation. Calves identified as having BRDC prior to weaning were 2.62 times as likely to have DFH before first calving as those classified as developing BRDC after weaning. Cows identified as having BRDC120 were 1.28 times as likely to have DFH between the first and second calving as were other cows. The BRDC120 designation was associated with a 233-kg (513-lb) lower 305-day mature equivalent value for first lactation milk production, but was not associated with longer or shorter calving intervals at maturity. CONCLUSIONS AND CLINICAL RELEVANCE Dairy cattle identified as having BRDC120 had increased risk of DFH before the first or second calving and lower first-lactation milk production estimates, compared with results for cattle without this finding. Further investigation of these associations is warranted.
León-Galván, Ma Fabiola; Barboza-Corona, José E; Lechuga-Arana, A Arianna; Valencia-Posadas, Mauricio; Aguayo, Daniel D; Cedillo-Pelaez, Carlos; Martínez-Ortega, Erika A; Gutierrez-Chavez, Abner J
Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DM (P resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study.
León-Galván, Ma. Fabiola; Barboza-Corona, José E.; Lechuga-Arana, A. Arianna; Valencia-Posadas, Mauricio; Aguayo, Daniel D.; Cedillo-Pelaez, Carlos; Martínez-Ortega, Erika A.; Gutierrez-Chavez, Abner J.
Thirty-two farms (n = 535 cows) located in the state of Guanajuato, Mexico, were sampled. Pathogens from bovine subclinical mastitis (SCM) and clinical mastitis (CLM) were identified by 16S rDNA and the sensitivity to both antibiotics and bacteriocins of Bacillus thuringiensis was tested. Forty-six milk samples were selected for their positive California Mastitis Test (CMT) (≥3) and any abnormality in the udder or milk. The frequency of SCM and CLM was 39.1% and 9.3%, respectively. Averages for test day milk yield (MY), lactation number (LN), herd size (HS), and number of days in milk (DM) were 20.6 kg, 2.8 lactations, 16.7 animals, and 164.1 days, respectively. MY was dependent on dairy herd (DH), LN, HS, and DM (P < 0.01), and correlations between udder quarters from the CMT were around 0.49 (P < 0.01). Coagulase-negative staphylococci were mainly identified, as well as Staphylococcus aureus, Streptococcus uberis, Brevibacterium stationis, B. conglomeratum, and Staphylococcus agnetis. Bacterial isolates were resistant to penicillin, clindamycin, ampicillin, and cefotaxime. Bacteriocins synthesized by Bacillus thuringiensis inhibited the growth of multiantibiotic resistance bacteria such as S. agnetis, S. equorum, Streptococcus uberis, Brevibacterium stationis, and Brachybacterium conglomeratum, but they were not active against S. sciuri, a microorganism that showed an 84% resistance to antibiotics tested in this study. PMID:25815326
Schils, R.L.M.; Haan, de M.H.A.; Hemmer, J.G.A.; Pol, van den A.; Boer, de J.A.; Evers, A.G.; Holshof, G.; Middelkoop, van J.C.; Zom, R.L.G.
A whole-farm dairy model was developed and evaluated. The DairyWise model is an empirical model that simulated technical, environmental, and financial processes on a dairy farm. The central component is the FeedSupply model that balanced the herd requirements, as generated by the DairyHerd model,
Lobago, F; Bekana, M; Gustafsson, H; Kindahl, H
A study was conducted to assess the reproductive performance and factors that influence reproductive efficiency of cows in smallholder dairy farms in Selalle, Central Ethiopia. Three hundred dairy farms (average herd size = 8) were visited and data on reproductive, breeding and management histories were collected and analysed. The overall geometric means for calving to conception interval (n=382) and duration after last calving (n=422) were 187 and 201 days in pregnant and non-pregnant cows, respectively. The least-squares mean calving to conception interval was higher (p < 0.05) in mixed crop-livestock production (MCLP) than in small urban dairy production (SUDP) systems and was lower (p < 0.01) in non-suckling than in suckling cows. District significantly influenced (p < 0.01) the least-squares mean duration after last calving and, among the districts, non-pregnant cows in Wuchale-Jida had the highest values, whereas cows in Sululta and Mulo had the lowest values. The overall average number of services per conception (+/-SD) and the first service conception rate were 1.6 +/- 1.0 (n=382) and 56% (n=456), respectively. The prevalences of abortion, dystocia (assisted parturition), retained fetal membrane, vulval discharge/endometritis and pre-weaning calf mortality were 1.4%, 1.3%, 5.4%, 2.8% and 17.4%, respectively. The present estimates of extended calving to conception interval and duration after last calving indicate poor reproductive performances of cows in Selalle smallholder dairy farms. The pre-weaning calf mortality rate is highly significant. Accordingly, a further detailed investigation is necessary to identify and quantify the specific reproductive disorders and associated interacting factors attributing to such poor performance and to determine the causes and predisposing factors behind such high calf mortality.
Brenda Patricia Murphy
Full Text Available A 12-month longitudinal study was undertaken on two dairy herds to ascertain the Shiga-toxin producing Escherichia coli (STEC O157 and O26 shedding status of the animals and its impact (if any on raw milk. Cattle are a recognised reservoir for these organisms with associated public health and environmental implications. Animals shedding E. coli O157 at >10,000 CFU/g of faeces have been deemed super-shedders. There is a gap in the knowledge regarding super-shedding of other STEC serogroups. A cohort of 40 lactating cows from herds previously identified as positive for VTEC in a national surveillance project were sampled every second month between August, 2013 and July, 2014. Metadata on any potential super-shedders was documented including e.g. age of the animal, number of lactations and days in lactation, nutritional condition, somatic cell count and content of protein in milk to assess if any were associated with risk factors for super-shedding. Recto-anal mucosal swabs, raw milk, milk filters and water samples were procured for each herd. The swabs were examined for E. coli O157 and O26 using a quantitative real time PCR method. Counts (CFU swab-1 were obtained from a standard calibration curve that related real-time PCR cycle threshold (Ct values against the initial concentration of O157 or O26 in the samples. Results from Farm A: 305 animals were analysed; 15 E. coli O157 (5% were recovered, 13 were denoted STEC encoding either stx1 and/or stx2 virulence genes and 5 (2% STEC O26 were recovered. One super-shedder was identified shedding STEC O26 (stx1&2. Farm B: 224 animals were analysed; eight E. coli O157 (3.5% were recovered (seven were STEC and 9 (4% STEC O26 were recovered. Three super-shedders were identified, one was shedding STEC O157 (stx2 and two STEC O26 (stx2. Three encoded the adhering and effacement gene (eae and one isolate additionally encoded the haemolysin gene (hlyA. The results of this study show, low numbers of super
Brouwer, H; Stegeman, Arjan; Straatsma, J W; Hooijer, Gerrit; van Schaik, Gerdien
Dairy cattle health is often assessed during farm visits. However, farm visits are time consuming and cattle health is assessed at only one point in time. Moreover, farm visits are poorly comparable and/or repeatable when inspection is carried out by many different professionals. Many countries
Case Description: 1,081 newborn calves from a commercial dairy were tested for bovine viral diarrhea virus antigen by pooled RT-PCR as part of a screening program. Ear tissue from twenty six calves initially tested positive and 14 confirmed positive with antigen capture ELISA two weeks later (1.3...
The research described in this thesis focuses on the relation between dairy herd management, milk production per cow, and gross margin per 100 kg of milk. The study was carried out as an explorative and empirical study. The thesis is composed of five parts.
Silva, Jenevaldo B; Fagundes, Gisele M; Soares, João P G; Fonseca, Adivaldo H; Muir, James P
Health and production management strategies influence environmental impacts of dairies. The objective of this paper was to measure risk factors on health and production parameters on six organic and conventional bovine, caprine, and ovine dairy herds in southeastern Brazil over six consecutive years (2006-2011). The organic operations had lower milk production per animal (P ≤ 0.05), lower calf mortality (P ≤ 0.05), less incidence of mastitis (P ≤ 0.05), fewer rates of spontaneous abortions (P ≤ 0.05), and reduced ectoparasite loads (P ≤ 0.05) compared to conventional herds and flocks. Organic herds, however, had greater prevalence of internal parasitism (P ≤ 0.05) than conventional herds. In all management systems, calves, kids, and lambs had greater oocyte counts than adults. However, calves in the organic group showed lower prevalence of coccidiosis. In addition, animals in the organic system exhibited lower parasitic resistance to anthelmintics. Herd genetic potential, nutritive value of forage, feed intake, and pasture parasite loads, however, may have influenced productive and health parameters. Thus, although conventional herds showed greater milk production and less disease prevalence, future research might quantify the potential implications of these unreported factors.
Barrio, M.; Vigo, M.; Quintela, L.A.; Becerra, J.J.; García-Herradón, P.J.; Martínez-Bello, D.; Fernandez-Sanchez, F.I.; Prieto, A.; Cainzos, J.; Peña, A.I.
The aim of this study was to evaluate the influence of subclinical endometritis (SE) on the reproductive performance of dairy cows. Ninety-four dairy cows of parity 1 to 8, distributed in 25 herds, were examined once between 30 and 45 days in milk using transrectal palpation, vaginoscopy and ultrasonography. A cytological sample of the endometrium was taken only from cows with an apparent healthy uterus (n=65). Serum glucose, total cholesterol, triglycerides, non-esterified fatty acids, β-hydroxybutyrate, total proteins, albumin, urea and hepatic enzymes were analyzed. Reproductive indexes were recorded during the next 11 months. Endometrial cytology was considered indicative of SE if percentage of polymorphonuclear neutrophils was superior to 5% of all cells present in the smear, except erythrocytes. Results indicated that 14.9% of the cows sampled for uterine cytology had SE, and that healthy cows become pregnant significantly before than those with SE (hazard ratio=2.35; 95% confidece interval: 1.05-5.3). From all the metabolic and productive variables analyzed, only triglycerides affected negatively to reproduction; serum albumin concentration, body condition score and milk production had positive effects on the reproductive performance. In conclusion, our results indicate that SE has a negative impact on reproductive performance and uterine cytology is necessary to diagnose it since almost 15% of the affected animals were not detected by other diagnosis methods. (Author)
Romero, J J; Breda, S Van; Vargas, B; Dolz, G; Frankena, K
A cross-sectional study was conducted to assess the effect of neosporosis on productive and reproductive parameters in dairy cows. Cows (n=2743) from 94 farms located in the most important dairy areas in Costa Rica were used in the study. The size of the herds ranged from 32 to 379 females (mean=110, median=125). An indirect ELISA was used to determine the serostatus of the cows towards Neospora caninum. The effect of neosporosis on milk production was analysed by a mixed linear model. In addition, the effects on calving interval (days) and calving to conception interval (days) were analysed by survival analysis. The risk of abortion in relation to N. caninum serostatus was assessed by logistic regression, with herd as a random effect. Overall, 1185 of 2743 cows (43.3%) were seropositive for Neospora. Eighty-nine of 94 (94.7%) farms were classified as Neospora-seropositive. It was estimated that cows seronegative to Neospora produced an additional 84.7L of milk (P=0.6). Serostatus did not have a significant effect on the length of the calving interval in the Cox proportional hazard survival analysis (Hazard ratio=1.2, 95% CI: 0.9, 1.4). The logistic regression model had a weak positive association between serostatus and abortion (OR 1.7, 95% CI: 0.8, 3.9), but did not show a strong association between serostatus and the number of services per conception (OR=0.95, 95% CI: 0.7, 1.3). In conclusion, there were no significant effects of Neospora serostatus on production and reproductive performance in this study.
Balancing the supply of on-farm grown forages with the production targets of the dairy herd is a crucial aspect of the management of a dairy farm. Models which provides a rapid insight of the impact of the ration, feed quality and feeding management on feed intake and performance of dairy cows
Kaniyamattam, K; Block, J; Hansen, P J; De Vries, A
The objective of this study was to implement an in vitro-produced embryo transfer (IVP-ET) system in an existing stochastic dynamic dairy simulation model with multitrait genetics to evaluate the genetic, technical, and financial performance of a dairy herd implementing an exclusive IVP-ET or artificial insemination (AI) system. In the AI system, sexed semen was used on the genetically best heifers only. In the IVP-ET system, all of the animals in the herd were impregnated with female sexed embryos created through in vitro fertilization of oocytes collected from animals of superior genetics for different traits of interest. Each donor was assumed to yield on average 4.25 transferable embryos per collection. The remaining animals in the herd were used as recipients and received either a fresh embryo or a frozen embryo when fresh embryos were not available. Selection of donors was random or based on the greatest estimated breeding value (EBV) of lifetime net merit (NM$), milk yield, or daughter pregnancy rate. For both the IVP-ET and AI systems, culling of surplus heifer calves not needed to replace culled cows was based on the lowest EBV for the same traits. A herd of 1,000 milking cows was simulated 15 yr over time after the start of the IVP-ET system. The default cost to produce and transfer 1 embryo was set at $165. Prices of fresh embryos at which an exclusive IVP-ET system financially breaks even with the comparable AI system in yr 15 and for an investment period of 15 yr were also estimated. More surplus heifer calves were sold from the IVP-ET systems than from the comparable AI systems. The surplus calves from the IVP-ET systems were also genetically superior to the surplus calves from the comparable AI systems, which might be reflected in their market value as a premium price. The most profitable scenario among the 4 IVP-ET scenarios in yr 15 was the one in which NM$ was maximized in the herd. This scenario had an additional profit of $8/cow compared with a
Wood, Mary E; Fox, Karen A; Jennings-Gaines, Jessica; Killion, Halcyon J; Amundson, Sierra; Miller, Michael W; Edwards, William H
We evaluated bighorn sheep ( Ovis canadensis ) ewes and their lambs in captivity to examine the sources and roles of respiratory pathogens causing lamb mortality in a poorly performing herd. After seven consecutive years of observed December recruitments of sheep from the remnant Gribbles Park herd in Colorado, US were captured and transported to the Thorne-Williams Wildlife Research Center in Wyoming in March 2013. Ewes were sampled repeatedly over 16 mo. In April 2014, ewes were separated into individual pens prior to lambing. Upon death, lambs were necropsied and tested for respiratory pathogens. Six lambs developed clinical respiratory disease and one lamb was abandoned. Pathology from an additional six lambs born in 2013 was also evaluated. Mycoplasma ovipneumoniae , leukotoxigenic Mannheimia spp., leukotoxigenic Bibersteinia trehalosi , and Pasteurella multocida all contributed to lamb pneumonia. Histopathology suggested a continuum of disease, with lesions typical of pasteurellosis predominating in younger lambs and lesions typical of mycoplasmosis predominating in older lambs. Mixed pathology was observed in lambs dying between these timeframes. We suspected that all the ewes in our study were persistently infected and chronically shedding the bacteria that contributed to summer lamb mortality.
Klein, D; Alispahic, M; Sofka, D; Iwersen, M; Drillich, M; Hilbert, F
The objectives of this study were to evaluate the presence of thermophilic Campylobacter in feces of calves with and without diarrhea on dairy farms and to survey farm characteristics and management practices to define risk factors for the presence of Campylobacter. Fifty dairy farms were chosen based on the presence of calf diarrhea, and 50 farms in which calves were free from diarrhea served as a standard of comparison. In total, fecal samples were taken from 382 calves. Farm data and management practices were surveyed using a questionnaire on farm. Campylobacter were isolated from fecal samples and colonies were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. Campylobacter spp., mainly Campylobacter jejuni (93% of isolated species), were detected on 33% of the farms and in 14.9% of the calves. Detection of Campylobacter did not differ between farms or between calves with and without diarrhea, although we found a tendency for calves suffering from diarrhea to shed Campylobacter more often. Calves may act as a reservoir of Campylobacter and may therefore lead to infections of other animals and humans. To define control strategies to reduce Campylobacter in calves, we identified on-farm risk factors. The presence of poultry on the farm, the time of cow-calf separation following birth, the use of an individual bucket for each calf, the feeding of waste milk, and the duration of individual housing were variables significantly associated with the appearance or absence of Campylobacter. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
O'Donovan, M.; Ruelle, Elodie; Coughlan, F.; Delaby, Luc
The aim of high-profitability grazing systems is to produce milk efficiency from grazed pasture. There is very limited information available on the milk production capacity of dairy cows offered a grass-only diet for the main part of her lactation. In this study, spring-calving dairy cows were managed to achieve high milk production levels throughout the grazing season without supplementation. The calving date of the herd was 12 April; the herd had access to grass as they calved a...
The objective of the present study was to evaluate the effects of clinical mastitis at the beginning of lactation on reproductive performance of dairy cows in Algeria. Calving to first insemination and calving to conception intervals, number of insemination per conception and conception rate at the first artificial insemination were ...
Performance of Improved Dairy Cattle Technologies Among Farmers in. Northern Nigeria. Http://dx.doi.org/10.4314/jae.v20i1.1. Saleh, M.K.. Department of Agricultural Economics and Rural Sociology,. Ahmadu Bello University, Zaria. Email: email@example.com or firstname.lastname@example.org. Phone: 08123431446 / ...
Dobson, H; Smith, Rf; Royal, Md
There is evidence that the reproductive performance of dairy cows has declined as milk yields have increased over the last 40 years. Identifying the precise cause(s) of this problem may provide focused solutions. Intensive genetic selection for very high yields has reduced fertility, due mainly...
Sep 5, 2011 ... ISSN 1684–5315 © 2011 Academic Journals. Full Length ... This study was conducted to evaluate the effect of supplemental chromium on performance and blood serum biochemistry of dairy ... Serum biochemistry concentrations (serum glucose, cholesterol, triglyceride, total protein, and cortisol and insulin ...
International trade with genetic material has lead to the foundation of Interbull, an international organization that performs international evaluations of dairy bulls, enabling countries to obtain breeding values of foreign bulls on their on scale. Not all countries have the possibility to participate in the evaluations with their own ...
Lehmann, Jesper Overgård; G. Fadel, J.; Mogensen, Lisbeth
an extended compared with a shorter lactation. Increasing CInt increased the dry period length with 3 to 5 d. In conclusion, the group of cows with longer CInt were able to produce at least equivalent amounts of ECM per feeding day when the CInt was up to 17 to 19 mo on these 4 commercial dairy farms....... that cows are able to maintain milk yield per feeding day when the length of the calving interval (CInt) is increased. Milk yield per feeding day is defined as the cumulated lactation milk yield divided by the sum of days between 2 consecutive calvings. The main objective of this study was to investigate...... the milk production of cows managed for lactations of different lengths, and the primary aim was to investigate the relationship between CInt, parity, and milk yield. Five measurements of milk yield were used: energy-corrected milk (ECM) yield per feeding day, ECM yield per lactating day, cumulative ECM...
Guimarães, F F; Manzi, M P; Joaquim, S F; Richini-Pereira, V B; Langoni, H
Cows are probably the main source of contamination of raw milk with Staphylococcus aureus. Mammary glands with subclinical mastitis can shed large numbers of Staph. aureus in milk. Because of the risk of this pathogen to human health as well as animal health, the aim of this paper was to describe an outbreak of mastitis caused by methicillin-resistant Staph. aureus (MRSA), oxacillin-susceptible mecA-positive Staph. aureus (OS-MRSA), and methicillin-susceptible Staph. aureus (MSSA) on a dairy farm. Milk samples were obtained from all quarters, showing an elevated somatic cell count by the California Mastitis Test. The isolates were identified by phenotypic and genotypic methods. Staphylococcus spp. were isolated from 53% (61/115) of the milk samples, with 60 isolates identified as Staph. aureus (98.4%) and 1 isolate identified as Staphylococcus epidermidis (1.6%). The presence of the mecA gene was verified in 48.3% of Staph. aureus isolates. Of the Staph. aureus isolates, 23.3% were MRSA and 25.0% were OS-MRSA. The total of mastitis cases infected with MRSA was 12.2%. The detection of this large percentage of mastitis cases caused by MRSA and OS-MRSA is of great concern for the animals' health, because β-lactams are still the most important antimicrobials used to treat mastitis. In addition, Staph. aureus isolates causing bovine mastitis represent a public health risk. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Irungu, K.R.G.; Mbugua, P.N.
Majority of dairy farmers in Kenya produce milk from cows fed on roughage. The cow performance follows seasonal variability in quality and quantity of roughage. The objective of the current study was to increase cow performance and maintain productivity of a rhodes grass (chloris gayana) ley. Twenty-four Freisian cows in their second to third lactation were strip grazed on fertilized irrigated Rhodes grass at a stocking rate of 0.034 ha per cow. Four dietary groups of six cows were allocated to one of our diets. one group got no dairy meal while the other three groups were supplemented at a 1kg of dairy meal per 10, 5 and 2.5 kg of 4% fat corrected milk dairy. this amount to 0, 386, 750 and 1542 kg dairy meal (89.4%, DM, 93.7 OM, 16.8, CP and CF) during the lactation. during the 43 - week lactation, records on pasture nutrient yield, nutrient intake, milk yield, liveweight, reproduction and subsequent calf birth weight were collected. The Rhodes grass ley produced 20.7 (ranging from 16.7 to 28.7) t of dry matter (DM) per hectare and cows harvested 16.0 (12.0 to 24.0) t during the 43 weeks.The Rhodes grass contained 32.1, 87.7, 10.8, and 32.3% DM, organic matter (OM), crude protein (CP) and crude fiber (CF) respectively. Mean stubble of 4.7 (3.9 to 6.0) t DM per hectare was left at pasture. Feeding dairy meals significantly increased (P 0.05) affect batter fat content (3.78 to 3.96%). It maintained (P > 0.05) cow liveweight and increased (P < 0.05) calf birth weight from 32.7 to 37.2 kg. Feeding dairy meal did not affect oestrus cycling. Extreme supplementation, 1542 kg dairy meal, decreased (P < 0.05) fertility. Insemination per conception and calving interval increased (P < 0.05) from 1.5 to 3.5 and 522 days. The findings in the current study show that pasture yield can be increased by over 590% dry matter from 3.5 t obtained from natural pasture containing Kikuyu and Star grasses. The Rhodes grass yield can be increased to 232% of national average yield of 1300
Rodrigo Cesar dos Reis Tinini
Full Text Available The objective of the present study was to characterize the food sources, as well as the composition and quality of milk obtained from household farms of western Paraná State (Brazil with and without technical assistance during the different seasons. For such, 24 properties were selected, 12 of which only received assistance and technical support. Four milk samples were taken (summer, autumn, winter and spring to assess the physicochemical composition, somatic cell count and total bacterial count and feed supplied to the animals to assess the chemical composition (crude protein, ash, dry matter and neutral detergent fiber. The data were analyzed in a completely randomized design with a 2 × 4 factorial arrangement; the first factor was the presence and absence of technical assistance and the second factor was the four seasons of the year. Due to the dairy tradition of properties in the region, technical assistance had no significant effects on the health and nutritional quality of food, the number of animals, the production, or total bacterial count, which suffered oscillations only depending on the seasons of the year. However, the presence of assistance contributed to reducing somatic cell counts of milk produced and marketed. The technical assistance does not affect the quality of forages and concentrates used or the milk composition; however, it improves the sanitary quality of the milk produced throughout the four seasons of the year in household farms of western Paraná.
Kumar, B; Pachauri, S P
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. Copyright 2000 Harcourt Publishers Ltd.
Macmillan, K; Loree, K; Mapletoft, R J; Colazo, M G
heifers. Breeding heifers based on detected estrus increases labor, but has the potential to increase fertility. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Lambertz, Christian; Völker, Denise; Janowitz, Ulrich; Gauly, Matthias
Vaginal mucus during estrus was examined with the Metricheck device and the relationship to the reproduction of high-yielding dairy cows was studied. The study was conducted in 99 dairy herds located in Western Germany and 1348 Holstein-Friesian heifers and cows showing spontaneous estrus were examined. Independent of the Metricheck result, the animals were inspected by professional insemination technicians and those suitable for insemination (n = 989) were bred by artificial insemination (AI). Reproductive performance was characterized by non-return rate at 90 days (NRR90). The discharge of the animals predominantly had a clear appearance (70%) and a stringy consistency (80%). Animals with clear vaginal discharge had higher NRR90 (56%; n = 697) than animals with abnormal (turbid, mucopurulent, purulent, sanguineous) vaginal secretion (48%, n = 292; P 130 days; 62%) intervals (P 45 kg) milk yield class. In conclusion, the use of the Metricheck device integrated into the insemination procedure is recommended to identify dairy cows suffering severely from uterine disease. © 2014 Japanese Society of Animal Science.
Creatine supplementation improves repetitive, short-term performance. It has not been shown that exclusion of meat from the diet would impair repetitive short-term performance. In contrast, reduction of protein intake and a concomitant increase of carbohydrate intake during a period of 3-5 days improves anaerobic (2-7 minutes) performance. The protein intake in a mixed or lacto-vegetarian diet is adequate even for elite athletes, providing that energy requirements are met. Many dietary supplements have been suggested to increase muscle mass and/or to decrease fat mass. Although the effects of conjugated linoleic acid on body composition in athletes are not clear, some positive findings in untrained, obese individuals call for more studies. Strenuous training may impair immune function and increase the susceptibility to infections. Exclusion of meat from the diet does not seem to have adverse effects on immune function. Glutamine supplementation (>3-6 g/day) may improve immune function, but more studies are needed. Similarly, more studies on the possible effects of whey protein and probiotic supplementation on immune function and performance in physically highly active individuals are warranted. Vitamin and mineral balance are not usually a problem among athletes. Notable exceptions may be calcium and iron in some females. Increased calcium intake in athletes with hormonal and menstrual disturbances could theoretically help in maintaining bone status; however, no data are available. A diet with meat may help in maintaining adequate iron stores.
Nielsen, Liza Rosenbaum; Dohoo, Ian
year after becoming at risk again, and then approached the hazard in herds without known prior infections 2 to 3 years after becoming test-negative. This showed that herds with prior infections need to maintain a high level of biosecurity for at least 3 years after becoming test-negative for S. Dublin...... and maintain a high level of biosecurity....
Bartels, C.J.M.; Hogeveen, H.; Schaik, van G.; Wouda, W.; Dijkstra, Th.
In this study, direct economic losses due to Neospora caninum infection, based on actual data from N. caninum seropositive reference herds and from herds that experienced an N. caninum- associated abortion epidemic, were calculated using a stochastic model with random elements. The results
The effect of farm (herd) and season of calving on the reproductive performance of Sanga cows in smallholder peri-urban dairy farms in the Accra plains. SA Okantah, FY Obese, OK Oddoye, PK Karikari, P Gyawu, MJ Bryant ...
Ma, H; Oxley, L; Rae, A; Fan, C; Huang, J; Rozelle, S
China's dairy farm structure has experienced fundamental changes across farm types. As the number of backyard farms has dramatically declined, the share of dairy cows from backyard farms has decreased by 22.4% from 2003 to 2008. However, the herd numbers of larger dairy farms have increased. In particular, the share of dairy cows has risen by 18.8% on small farms, by 22.2% on medium farms, and by 80.8% on large farms over the same period. Total factor productivity was decomposed into technical efficiency and technological change on China's dairy farms using the stochastic production frontier framework. The estimated results indicate that patterns of productivity growth appear to have shifted in the 2000s compared with the 1990s, from generally driven by technological change to exclusively driven by technological change on backyard and small farms and uniquely driven by the improvement of technical efficiency on large farms. Tests of the econometric assumption indicate that the variations in total factor productivity growth patterns across farm types and regions are likely caused by the feed input biases and cropping production practice. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Full Text Available Current knowledge about the function of the reproductive tract and appropriate use of hormonal drugs affords control of the oestrus cycle of cows. One of the hormonal protocols is OvSynch, which enables artificial insemination (AI to be performed at the precise optimum time without control of the ovaries and uterus. Use of such protocols in reproductive management allows oestrus cycles to be synchronised and cows to be effectively inseminated without oestrous detection, which is time-consuming and difficult in farms with numerous cows. Therefore, OvSynch has become the first management tool for AI and is an alternative method to heat detection. Over the 20 years since its first implementation, OvSynch has been modified many times to improve its reproduction outcomes and widen its use. Besides its original use for heat synchronisation, it is also used in many ovarian disorders as a therapeutic method. This review article describes the possibilities which OvSynch provides, its current modifications, various applications, and the advantages and disadvantages of its use in practice.
Rueda López MA
Full Text Available Abstract Sow performance is a key component of the productivity of commercial pig farms. Reproductive failure in the sow is common in pig production. For every 100 sows served, 89 should farrow. In absence of specific diseases such as porcine parvovirus, pseudo-rabies, swine fever, leptospirosis and brucellosis, management failures are the most important causes of loss. A syndrome associated with reproductive inefficiency, and post-service vaginal discharge and high sow mortality in a commercial pig farm is described. Pregnancy failures exceeded 20% and sow mortality exceeded 12% for two consecutive years. The abnormal post-service vaginal discharge rate was 1.7% during the period of investigation. An investigation involving an analysis of farm records, a review of breeding management practices, clinical examinations, laboratory analysis and examination of urogenital organs was conducted. The main contributing factors found were a sub-optimal gilt breeding management, an inadequate culling policy in combination with a sub-optimal culling rate and the presence of cystitis in more than 1% of the urogenital organs examined. The high sow mortality rate was related to an aged breeding herd. A control programme was recommended based on management changes involving oestrus detection, movement of gilts post-service, hygiene in the service area, boar exposure post-service and urinary acidification. This programme failed to increase the farrowing rate due to incomplete implementation of the recommendations made. The farrowing rate increased to 86.5% subsequent to a farm manager change in January 2005, which resulted in complete implementation of the control programme.
Marcia de Oliveira Franco
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.
Veldhuis, A M B; Santman-Berends, I M G A; Gethmann, J M; Mars, M H; van Wuyckhuise, L; Vellema, P; Holsteg, M; Höreth-Böntgen, D; Conraths, F J; van Schaik, G
Schmallenberg virus (SBV), a novel orthobunyavirus that rapidly spread throughout north-western Europe in 2011, caused congenital malformations in lambs and goat kids (Van den Brom et al., 2012) and newborn calves (Hoffmann et al., 2012). The impact of the SBV epidemic seemed limited however, in terms of the number of affected herds with malformed offspring (European Food Safety Authority, 2012b). Nevertheless, little is known with regard to the overall within-herd impact of SBV infection. The objective of the current study was to quantify the impact of the 2011 SBV epidemic on the productivity of dairy cattle in the Netherlands and the district of Kleve, Germany. For the Netherlands, several multilevel multivariable statistical models were applied on eight productivity parameters regarding milk production, reproductive performance and mortality. All four fertility parameters analysed were slightly but significantly reduced between August 1st and November 1st 2011 compared to the reference period in 2009-2010. Between August 15th and September 19th 2011, the average loss in milk production per cow was -0.26kg (95% CI: -0.30; -0.22) per day in dairy herds, compared to the reference period (pcow in a subgroup of dairy herds that notified malformations in newborn calves during the mandatory notification period in the Netherlands was -0.43kg (95% CI: -0.59; -0.28) per day (pmilk yield, two fertility parameters and the number of rendered calves in this specific region were analysed. There was a small but significant increase in the number of secondary and third inseminations between August 1st and November 1st 2011, indicating reduced fertility. No significant change in calf mortality was observed in the assumed SBV period. Milk production at district level did not seem to be affected by SBV in August and September 2011. SBV had no or limited impact on mortality rates, which was as expected given the relatively mild expression of SBV in adult cows and the low incidence
Antimicrobial susceptibility of Staphylococcus aureus causing bovine mastitis in Argentine dairy herds Sensibilidad a los antimicrobianos de Staphylococcus aureus causantes de mastitis bovina en rodeos lecheros de Argentina
Full Text Available We assessed the in vitro activity of selected antimicrobial agents against 95 Staphylococcus aureus strains causing both clinical and subclinical bovine mastitis belonging to 61 dairy farms from the Central dairy area of Argentina. Minimal inhibitory concentrations (MICs of penicillin, oxacillin, gentamicin, erythromycin, enrofloxacin and florfenicol were estimated. In addition, the agar diffusion test was performed. MIC50 and MIC90 were as follows: penicillin, 0.05 and 4 µg/ml; oxacillin, 0.25 and 0.25 µg/ml; gentamicin, 0.25 and 0.5 µg/ml; erythromycin 0.125 and 0.25 µg/ml; enrofloxacin 0.25 and 0.5 µg/ml, and florfenicol 4 and 8 µg/ml. b-lactamase activity was detected in 89% of 46 penicillin- resistant strains. Apart from penicillin, antimicrobial resistance in S. aureus causing bovine mastitis remains rare in Argentine dairy farms.Se evaluó la actividad in vitro de un grupo seleccionado de antimicrobianos contra 95 aislamientos de Staphylococcus aureus obtenidos de casos de mastitis bovina clínica y subclínica, en 61 rodeos lecheros de la cuenca central de Argentina. Fueron estimadas las concentraciones inhibitorias mínimas (CIM de penicilina, oxacilina, gentamicina, eritromicina, enrofloxacina y florfenicol. Además se realizó la prueba de difusión en agar. Las CIM50 y CIM90 obtenidas fueron: penicilina 0,05 y 4 µg/ml; oxacilina 0,25 y 0,25 µg/ml; gentamicina 0,25 y 0,5 µg/ml; eritromicina 0,125 y 0,25 µg/ml; enrofloxacina 0,25 y 0,5 µg/ml y florfenicol 4 y 8 µg/ml. Se detectó actividad de b-lactamasa en el 89% de las cepas resistentes a la penicilina. A excepción de lo observado para penicilina, la resistencia a los antimicrobianos en S. aureus causantes de mastitis bovina en Argentina parece ser un fenómeno poco frecuente.
Reinaldo Henrique Borger
Full Text Available Increasing concern about some animal production systems has placed considerable value on humanitarian breeding systems, aimed at ensuring animal welfare and comfort. Raising calves is one of the most important stages in a milk production system. This study aimed to evaluate and compare the performance of Holstein dairy calves raised by two farming systems: conventional individual (CI and collective with automatic calf feeder (CACF. Fourteen, 15-day-old Holstein dairy calves having an average initial body weight of 40 kg, were used. The animals were distributed in a completely randomized design with seven animals per treatment. The variables evaluated were the milk and feed intake, body weight, hip height, thoracic circumference and daily weight gain. The average milk intake was lower in the CACF (3.5 L animal-1 day-1 than CI (5.1 L animal-1 day-1 system. However, the feed intake was higher in the CACF (1.205 kg animal-1 day-1 compared to CI (0.910 kg animal-1 day-1 system. Body weight, thoracic circumference, hip height and daily weight gain were similar between the two systems. The CACF raised calves had a higher concentrate intake and lower milk intake than the calves raised under the CI system.
Græsbøll, Kaare; Kirkeby, Carsten Thure; Nielsen, Søren Saxmose
using a herd level curve allows for estimating the cow production level from first the recording in the parity, while a two-parameter model requires more recordings for a credible estimate, but may more precisely predict persistence, and given the independence of parameters, these can be easily drawn....... Furthermore, we investigated how the parameters of lactation models correlate between parities and from dam to offspring. The aim of the study was to provide simple and robust models for cow level milk yield and somatic cell count for fitting to sparse data to parameterize herd- and cow-specific simulation...... than somatic cells per milliliter. A positive correlation was found between relative levels of the total somatic cell count and the milk yield. The variation of lactation and somatic cell count curves between farms highlights the importance of a herd level approach. The one-parameter per cow model...
Ettema, Jehan Frans; Østergaard, Søren; Sørensen, M K
strategies based on the phenotypical states of the individual animals over a number of years. Typically, the genetic levels of replacement heifers in these models are not different from those of the culling candidates in the herd; continuous genetic improvement in the population is ignored. The importance...... of including genetic progress when evaluating reproductive strategies with simulation models has not been explored. Improved reproductive efficiency does allow a higher selection intensity of which cows to stay in the herd and give birth to own young stock....
Full Text Available Following the emergence of the Bluetongue virus serotype 8 (BTV-8 in France in 2006, a surveillance system (both passive and active was implemented to detect and follow precociously the progression of the epizootic wave. This system did not allow a precise estimation of the extent of the epizootic. Infection by BTV-8 is associated with a decrease of fertility. The objective of this study was to evaluate whether a decrease in fertility can be used to evidence the under-reporting of cases during an epizootic and to quantify to what extent non-reported cases contribute to the total burden of the epizootic. The cow fertility in herds in the outbreak area (reported or not was monitored around the date of clinical signs. A geostatistical interpolation method was used to estimate a date of clinical signs for non-reported herds. This interpolation was based on the spatiotemporal dynamic of confirmed case herds reported in 2007. Decreases in fertility were evidenced for both types of herds around the date of clinical signs. In non-reported herds, the decrease fertility was large (60% of the effect in reported herds, suggesting that some of these herds have been infected by the virus during 2007. Production losses in non-reported infected herds could thus contribute to an important part of the total burden of the epizootic. Overall, results indicate that performance data can be used to evidence the under-reporting during an epizootic. This approach could be generalized to pathogens that affect cattle's performance, including zoonotic agents such as Coxiella burnetii or Rift Valley fever virus.
Van Saun, R J
Periparturient disease conditions affecting transition dairy cows have been recognized as a critical contributor to impaired dairy performance and have become a focal point of herd diagnostic investigations. Over the past 40 years use of blood sampling in the form of metabolic profiling has been applied to herd diagnostics with mixed impressions of diagnostic robustness. Research has greatly increased our understanding of underpinning mechanisms related to cow biology, management, environment and their interactions responsible for peripartum diseases. Elevated β-hydroxybutyrate (BHB) concentration (> 1.2 mmol/l) within 7-10 days following calving identifies high risk cows for therapeutic intervention. Herd evaluations with 15-25% of first week fresh cows with elevated BHB indicates significant disease risk and productive losses. Elevated peripartal serum nonesterified fatty acids (NEFA) also indicate increased disease risk. This review discusses documented (BHB, NEFA) and other potential analytes using individual or pooled samples useful for disease risk assessment or nutritional status and their application in risk-based or herd screening methods of herd metabolic profiling diagnostics. A pooled sample approach modified from the original Compton Metabolic Profile allows for more economic assessment of multiple analytes, though interpretation and herd-size application may be limited. Pooled samples between 5 and 10 individuals accurately represent arithmetic means of individuals. Most importantly metabolic profiles must be used in concert with other diagnostic metrics of animal and facility evaluations, body condition scoring and ration evaluation to be fully useful in herd evaluations.
Ivemeyer, Silvia; Bell, Nick J.; Brinkmann, Jan; Cimer, Kornel; Gratzer, Elisabeth; Leeb, Christine; March, Solveig; Mejdell, Cecilie; Roderick, Stephen; Smolders, Gidi; Walkenhorst, Michael; Winckler, Christoph; Vaarst, Mette
Achieving and maintaining a high herd health and welfare status is an important aim in organic livestock farming. The varying farming systems across and within countries call for models that are relevant for different farming types and that can be integrated into local practice. In stable
The effects of homogenization and heat processing on the chemical and in vitro digestion traits of milk from organic and conventional herds were compared. Raw milk from organic (>50% of dry matter intake from pasture) and conventional (no access to pasture) farms were adjusted to commercial whole a...
Mekonnen, S A; Koop, G; Melkie, S T; Getahun, C D; Hogeveen, H; Lam, T J G M
Knowledge of mastitis pathogens and their predominance as well as understanding of risk factors are prerequisites to improve udder health in a herd, region or country. In Ethiopia, such information is scarce, despite the fact that mastitis is an important cattle disease in the country. A
Mekonnen, Sefinew Alemu; Koop, G.; Melkie, S.T.; Getahun, C.D.; Hogeveen, H.; Lam, Theo J.G.M.
Knowledge of mastitis pathogens and their predominance as well as understanding of risk factors are prerequisites to improve udder health in a herd, region or country. In Ethiopia, such information is scarce, despite the fact that mastitis is an important cattle disease in the country. A
Full Text Available Abstract Background In Denmark, it has recently become mandatory for all dairy farmers with more than 100 cows to sign up for a herd health programme. Three herd health programmes are available. These differ in a number of aspects, including the frequency of veterinary visits and the farmer’s access to prescription drugs. The objective of this study was to investigate whether dairy farmers’ behavioural intentions, i.e. to call a veterinarian or start medical treatment on the day that they detect a cow with mild clinical mastitis (MCM, are different depending on the type of herd health programme. Methods A questionnaire survey based on the Theory of Planned Behaviour (TPB was conducted. TPB proposes that a person’s behavioural intention is strongly correlated with his or her actual behaviour. Three behavioural factors determine the behavioural intention: attitude, subjective norm and perceived behavioural control. Each of these factors is decided by a set of beliefs, each of which in turn is weighted by an evaluation: 1 the expected outcomes of performing the behaviour, 2 what a person believes that others think of the behaviour, and 3 the person’s perceived power to influence the behaviour. A set of statements about the treatment of MCM based on interviews with 38 dairy farmers were identified initially. The statements were rephrased as questions and the resulting questionnaire was distributed to 400 randomly selected Danish dairy farmers who use the two most restrictive herd health programmes, either Core or Module1, and to all 669 farmers with the least restrictive herd health programme, Module2. The association between intention and the herd health programme was modelled using logistic regression. Results The farmers with the Module2 herd health programme had a significantly higher behavioural intention to perform the behaviour, when compared to farmers with a more restrictive herd health programme (OR = 2.1, p Conclusion Danish dairy
of F1 crossbred cows to produce and develop improved dairy cattle breed at on station and back up the on farm ... Adequate information was generated through selection to maintain superior genotype for further ... The crossbred dairy technology was verified and demonstrated in the central highlands and was found to be.
Providing the ration as a Total Mixed Ration (TMR) is now common practice on most commercial dairy farms in the world for nearly all classes of animals. This practice decreases sorting of the individual ration components by dairy cattle. The objective of the experiment was to evaluate the effect of two feeding methods on ...
Evaluation of protein nutrition by metabolizable protein and urea fermentation potential. J. Dairy Sci. 58, 611. CASPER, D.P. & SCHINGOETE, D.J., 1984. Evaluation of urea and dried whey in diets of cows during early lactation. J. Dairy Sci. 67 (Suppl. I) 120, (Abstr.). CASTLE, M.E. & WATSON, J.N., 1984. Silage and milk.
Full Text Available Abstract Background Insulin secretion and tissue sensitivity to insulin is considered to be one of the factors controlling lipid metabolism post partum. The objective of this study was to compare glucose-induced blood insulin and metabolite responses in Estonian Holstein (EH, n = 14 and Estonian Red (ER, n = 14 cows. Methods The study was carried out using the glucose tolerance test (GTT performed at 31 ± 1.9 days post partum during negative energy balance. Blood samples were obtained at -15, -5, 5, 10, 20, 30, 40, 50 and 60 min relative to infusion of 0.15 g/kg BW glucose and analysed for glucose, insulin, triglycerides (TG, non-esterified fatty acids (NEFA, cholesterol and β-hydroxybutyrate (BHB. Applying the MIXED Procedure with the SAS System the basal concentration of cholesterol, and basal concentration and concentrations at post-infusion time points for other metabolites, area under the curve (AUC for glucose and insulin, clearance rate (CR for glucose, and maximum increase from basal concentration for glucose and insulin were compared between breeds. Results There was a breed effect on blood NEFA (P P P P P P th min nadir (P th min postinfusion (P Conclusion Our results imply that glucose-induced changes in insulin concentration and metabolite responses to insulin differ between EH and ER dairy cows.
Erskine, R J; Martinez, R O; Contreras, G A
Recent changes in the US dairy industry include increases in herd size and the proportion of milk that is produced by large herds. These changes have been accompanied by an increased reliance on hired employees and an increasing role of immigrant labor to perform critical tasks such as milking cows. Thus, there is a growing need for training and education programs for dairy employees because many employees lack previous dairy experience and employee turnover rates are problematic on many farms. Although extension programs have played an important role in the education and support of dairy producers and allied professionals in attaining improved milk quality, dairy employees have limited access to educational programs. Additionally, metrics to assess employee learning are not validated and the ability to sustain work-related behavioral change has not been well described. In this article, we propose a model that may further our understanding of communication and cultural barriers between dairy managers and employees, based on a demonstration project in 12 Michigan dairy herds. As part of this demonstration, a pilot survey was tested to assess the management culture on dairy farms. Results from this survey found that only 23% of employees across all herds were able to meet with farm management on a regular basis, 36% of employees did not know somatic cell count goals for the farm for which they worked, and 71% of employees stated they primarily received training on milking protocols by other employees or that they learned on their own. Latino employees were more likely to not know farm goals or receive primary training on milking protocols from other employees or on their own compared with their English-speaking counterparts. The survey information, along with input from focus group discussions with participating dairy producers, veterinarians, and employees, suggests that extension needs to build capacity for on-farm training and education for employees to support
Soltau, J B; Einax, E; Klengel, K; Katholm, J; Failing, K; Wehrend, A; Donat, K
The objective of the study was to assess the value of quantitative multiplex real-time PCR examination of bulk tank milk samples for bovine mastitis pathogens as a tool for herd level diagnosis. Using a logistic regression model, this study is aimed at calculating the threshold level of the apparent within-herd prevalence as determined by quarter milk sample cultivation of all lactating cows, thus allowing the detection of a herd positive for a specific pathogen within certain probability levels. A total of 6,335 quarter milk samples were collected and cultured from 1,615 cows on 51 farms in Germany. Bulk tank milk samples were taken from each farm and tested by bacterial culture as well as the commercial PCR assay Mastit 4A (DNA Diagnostic A/S, Risskov, Denmark) identifying Staphylococcus aureus, Streptococcus dysgalactiae, Streptococcus agalactiae, and Streptococcus uberis. In addition, PCR was performed on pooled herd milk samples containing milk aliquots from all lactating cows in each of the 51 herds. Only 1 out of the 51 herds was found PCR positive for Streptococcus agalactiae in bulk tank and pooled herd milk samples, and cultured quarter milk samples. Spearman's rank correlations between the cycle threshold value of bulk tank milk PCR and the apparent within-herd prevalence were calculated in regard to Staphylococcus aureus, Streptococcus dysgalactiae, and Streptococcus uberis. For these pathogens, significant correlations were found. If 1 bulk tank milk sample per herd was tested, the estimated within-herd prevalence thresholds for 90% probability of detection were 27.6% for Staphylococcus aureus, 9.2% for Streptococcus dysgalactiae, and 13.8% for Streptococcus uberis on the cow level. On the quarter level, the within-herd prevalence had to be at least 32.6% for Staphylococcus aureus, 1.7% for Streptococcus dysgalactiae, and 4.3% for Streptococcus uberis to detect a herd as positive using a single bulk milk sample. The results indicate that mastitis
Silviu Ionuţ Borş
Full Text Available The aim of the present study was to determine the effects of propylene glycol on metabolic variables of hepatic function, body condition score, milk fat-protein concentration and reproductive performance of dairy cows after ending administration. Postparturient dairy cows (n = 200 of Holstein Friesian breed were divided into two groups of 100 individuals. The experimental group received during days 0-7 post partum an oral daily dose of 600 ml of propylene glycol; the control group was without any supplement. The hepatic enzymes, glucose, cholesterol and serum albumin were measured on days 10-15, 45-50 and 70 post partum. Reproduction indicators of dairy cows were calculated from the farm recording data and the milk data record from a regular dairy control (days 10, 20, 30, and 50 post partum. Animals that received propylene glycol in the first 7 days post partum had reduced activities of aspartate transaminase and gamma-glutamyl transferase, elevated cholesterol concentration (P 0.05 and low milk fat percentage (P P 0.05. Our results suggest that some blood indicators of hepatic function, milk fat concentration and calving to first oestrus interval can be improved for 70 days post partum by the use of propylene glycol drenching in the first 7 days post partum. The beneficial effect of this treatment could be evaluated by easily available data, which can be used by practitioners in the field to analyze fertility problems in dairy herds and more exactly to examine whether metabolic stress, among other factors, is involved in the fertility problem.
Mweu, Marshal M.; Nielsen, Søren S.; Hisham Beshara Halasa, Tariq
Several decades after the inception of the five-point plan for the control of contagious mastitis pathogens, Streptococcus agalactiae (S. agalactiae) persists as a fundamental threat to the dairy industry in many countries. A better understanding of the relative importance of within- and between...
Santman-Berends, I.M.G.A.; Gonggrijp, M.A.; Hage, J.J.; Heuvelink, A.E.; Velthuis, A.; Lam, T.J.G.M.; van Schaik, G.
Extended-spectrum β-lactamase and AmpC-producing Escherichia coli (ESBL/AmpC) are an emerging problem and are hypothesized to be associated with antimicrobial use (AMU), and more specifically with the use of third- and fourth-generation cephalosporins. Whether ESBL/AmpC also occur in organic dairy
Santman - Berends, Inge; Gonggrijp, M A; Heuvelink, A E; Velthuis, A; Lam, T J G M; van Schaik, Gerdien; Hage, J. J.
Extended-spectrum β-lactamase and AmpC-producing Escherichia coli (ESBL/AmpC) are an emerging problem and are hypothesized to be associated with antimicrobial use (AMU), and more specifically with the use of third- and fourth-generation cephalosporins. Whether ESBL/AmpC also occur in organic dairy
Ramsbottom, G; Horan, B; Berry, D P; Roche, J R
As land becomes a limiting resource for pasture-based dairy farming, the inclusion of purchased supplementary feeds to increase milk production per cow (through greater dry matter intake) and per hectare (through increased stocking rate) is often proposed as a strategy to increase profitability. Although a plausible proposition, virtually no analysis has been done on the effect of such intensification on the profitability of commercial pasture-based dairy farm businesses. The objective of this study was to characterize the average physical and financial performance of dairy systems differing in the proportion of the cow's diet coming from grazed pasture versus purchased supplementary feeds over 4 yr, while accounting for any interaction with geographic region. Physical, genetic, and financial performance data from 1,561 seasonal-calving, pasture-based dairy farms in Ireland were available between the years 2008 and 2011; data from some herds were available for more than 1 yr of the 4-yr study period, providing data from 2,759 dairy farm-years. The data set was divided into geographic regions, based on latitude, rainfall, and soil characteristics that relate to drainage; these factors influence the length of the pasture growth season and the timing of turnout to pasture in spring and rehousing in autumn. Farms were also categorized by the quantity of feed purchased; farms in which cows received 30% of their annual feed requirements from purchased feed were considered to be categories representative of increasing levels of system intensification. Geographic region was associated with differences in grazing days, pasture harvested per hectare, milk production per cow and per hectare, and farm profitability. Farms in regions with longer grazing seasons harvested a greater amount of pasture [an additional 19kg of dry matter (DM)/ha per grazing day per hectare], and greater pasture harvested was associated with increased milk component yield per hectare (58.4kg of fat
Remo Alessio Malagnino
Full Text Available Electric production from renewable resources, such as solar photovoltaic (PV, is playing an increasingly essential role in the agricultural industry because of the progressive increase in the energy price from fossil fuels and the simultaneous decrease in the income deriving from farming activities. A central issue in the sustainable diffusion of PV technologies is represented by the actual energy efficiency of a PV system. For these reasons, a performance analysis has been carried out in order to assess the potentials offered by different PV plants within a defined geographical context with the aim of investigating the impact of each component has on the PV generator global efficiency and defining the main technical parameters that allow to maximise the annual specific electric energy yield of an architectonically integrated plant, installed in a dairy house, compared to a ground-mounted plant. The annual performances of three grid connected PV plants installed in the same dairy cattle farm have been analysed: two are architectonically integrated plants - i.e., a rooftop unidirectional and a multi-field systems (both 99 kWp - and the other is a ground-mounted plant (480 kWp. Furthermore, the electrical performances, estimated by the photovoltaic geographical information system (PVGIS, developed by the EU Joint Research Centre, and by an analytical estimation procedure (AEP, developed on the basis of a meteo-climatic database related to the records of the nearest weather station and integrated by the components’ technical specifications, have been compared with the actual yields. The best annual performance has been given by the ground-mounted PV system, with an actual increase of 26% and in the range of 6÷12% according to different estimations, compared to the integrated systems, which were globally less efficient (average total loss of 26÷27% compared to 24% of the ground-mounted system. The AEP and PVGIS software estimates showed a good
Sraïri, MT.; Farit, Y.
The main objective of this study is to assess dairy cattle reproduction performances from artificial insemination (Al) database, using inseminators' records from 1992 to 1998, in three Al circuits established in Settat province in Morocco. Simultaneously a field survey was conducted in the same region, from January to April 1999, to determine main structural parameters of dairy farms which influence Al. Data set analysis has shown an increase in total number of Al performed from an average of...
Kongsted, Anne Grete
Group-housing of non-lactating sows is becomming increasingly widespread in commercial sow herds in European countries as a result of changed legislation. Group-housing may lead to individual variation in feed intake, stress and fear, which may impair the reproduction ferformance. However, whether...... or the outcome of three fear tests were found. The results indicate that the unintended individual variation in feed intake in sows group-housed in commercial herds may be large enough to affect the reproduction performance. This calls for management initiatives to reduce unequal feed intake in group-housed sows....
Vaarst, Mette; Byarugaba, D.K.; Nakavuma, J.
in smallholder dairy farms in the Jinja district of Uganda. Two peri-urban groups and one rural group met for common learning and training two hours per fortnight during a 12-month period, facilitated by two local extension agents together with one or two scientists from Makerere University. Farmers rotated each...... knowledge and experience from training in systematic clinical examination of animals, evaluation of the farm environments, and identification of improvements. Much of the acquired new knowledge was about basic dairy cow management and husbandry practices. In addition, they gave examples of how they were now...... time between farms owned by group participants, which demanded mutual trust, openness and respect. From their own assessment the farmers felt they had improved their milk production and reduced mastitis incidence on their farms. In an evaluation workshop, they articulated how they had built up common...
Jessica Karina Poncheki
Full Text Available The objective of this study was to describe daily body weight (BW changes in the first 100 days of lactation in confined dairy cows and to associate BW loss with productive and reproductive performance. Data included 26,344 daily BW measurements of 372 Holsteins calving between June 2011 and June 2012 in a commercial herd in the South of Brazil. Cows were automatically weighed and were assigned according to parity. Individual measurements were smoothed using cubic splines, generating nadir BW, days to nadir BW and the BW loss (absolute and relative values. This approach used days in milk (DIM as a single smoothing variable. Body weight at calving differed across parities: 570.5, 653.5, and 699.9 kg, for the 1st, 2nd and 3rd and subsequent parities, respectively. Body weight at nadir also differed across parities: 521.5, 608.8, and 647.3 kg, respectively. Mean days from calving BW to nadir BW and mean loss of BW (kg from calving to nadir BW did not differ across parities, but relative BW change (kg/100 kg was larger in animals in first parity (-8.4 kg/100 kg than second parity (-6.6 kg/100 kg. However, cows in first parity had more chances for good reproduction than cows in third and subsequent parities (44.0% vs. 30.7%, respectively. There was no difference in the probability of adequate reproduction (pregnant until 180 DIM among cows with low, medium, or high milk yield. Furthermore, cows with low and medium BW loss (below 60 kg of BW change showed more likelihood to adequate reproduction than cows with high BW loss (above 60 kg of BW: 45.5 and 45.8% vs. 24.4%, respectively. Improvements in fertility of dairy cows should be achieved by minimizing body weight loss in early lactation.
Kaliti National Artificial Insemination Center (NAIC) and imported WWS bulls to produce improved dairy cattle breed at on station and to back up the on farm crossbreeding for synthetic breed generation and development. Materials and Methods. Study area. The study was carried out at Holetta Agricultural Research Center ...
Feb 2, 2015 ... ABSTRACT. Objective: The aim of the study was to estimate the technical and cost efficiencies of smallholder dairy farms in Kenya (Embu and Meru counties). Methodology and results: Data were collected through a cross-sectional survey from 135 (96 in Embu and 39 Meru) randomly sampled farms using ...
analyzed using descriptive statistics, F-test and gross margin analysis. The majority of improved dairy cattle farmers were in their middle age, majority of them (60%) have university degrees, had annual income of about N20, 000, 000.00. It also ..... (2008). No Difference between Postural Exercises and Strength and.
Anaerobic digestion is one of the most promising management options for dairy manure treatment. Manure wastewater from dairy farms has been used for methane production for decades. However, performance failure due to inadequate mixing is routine. In general, the mixng of anaerobic digester is achived throguh mechnical stirring, liquid circulation, and gas circulation, among which the gas circulation proves to be the most effcient way. In this work, we studied the liquid flow pattern of tw...
Full Text Available The purpose of this study was to examine possible relationship between milk urea and fertility of dairy cows using field data. This study also evaluated the influence of environmental factors on milk urea (MU and the relationship between MU and daily milk yield, milk fat and protein percentage. The data were collected at 11 dairy farms in the Vojvodina region. Reproductive dana and MU measurements were obtained from cows that calved between June 2013 and October 2015 and had a successful conception after calving. Statistical data processing was carried out by applying General Linear Model procedure, Statistics 13. Parity, calving season, season of milk control and farm were included in the models as fixed effects. Significant differences in MU concentrations were observed between farms (P<0.01, seasons (P<0.01 and parity (P<0.05. Highly significant (P<0.01 positive relationships were found between MU concentration and milk yield, fat and protein percentage and days open. Cows with MU levels below 10 mg dL-1 had the lowest day open interval (135.59 days and cows with MU higher than 35 mg dL-1 had the longest days open interval (163.18 days. The cows with the lowest mean MU values (< 10 mg dL-1, had the shortest days open interval (72.62 days, but cows with mean MU values between 20.01-25.00 mg dL-1 had the longest days open interval (161.78 days. Results of this study indicate that increased MU levels appear to have a negative effect on dairy cow fertility.
Duval, J E; Bareille, N; Fourichon, C
Organic dairy farmers must live up to the organic goal of 'good health' in respect the organic principles and regulation. Veterinarians could be the organic dairy farmers' expected sparring partners in reaching this goal but have found difficulties to establish advisory relationships with them....... The objectives of this study are -from organic dairy farmers' points of view- (i) to describe farmers' objectives and strategies regarding herd health, (ii) to describe private veterinarians' roles in farmers' animal health promotion strategies and (iii) to identify farmers' reasons for accepting veterinarians...... in an advisory role. Fourteen organic dairy farmers were interviewed using qualitative research interviews. Data collection and analysis was performed using a modified approach to Grounded Theory. Organic dairy farmers had animal health management strategies focusing on animal health promotion. Veterinarians had...
The effects of sour gas plant emissions on dairy herds are described. A veterinarian establishing a practice in Rocky Mountain House, Alberta, found that dairy herds in that area suffered from a disproportionately higher occurrence of health problems than Minnesota herds with similar types of management. These problems are postulated to result from acid-forming emissions from two large sour gas plants in the area (the Ram River and Gulf Strachan plants). Health problems found in dairy cattle in the Rocky Mountain House area were: unthriftiness, increased susceptibility to infectious diseases, reproductive problems, and 'downer' animals (cows unable to stand up unassisted). Problems related to the reproductive organs were the most apparent. Clinical observations of problems in dairy herds are described. Since the levels of emissions from the plants have decreased, incidence of problems in dairy herds has also decreased. 1 ref., 2 figs
Full Text Available Abstract Over a period of two years, growth rate and health were measured for dairy calves allowed to suckle their mothers up to 6–8 weeks of age. Thirty-one calves were weighted weekly, and the mean daily growth rate was 1.2 ± 0.03 kg from birth up to 13 weeks of age. Illness in calves and young stock was not observed. In the cows, the mean incidences of ketosis, displaced abomasum, puerperal paresis, mastitis, teat injury and retained placenta were 0, 0, 8, 22, 1 and 1%, respectively, during a 6-year period. The mean daily gain of 56 growing bulls was 1.4 kg when slaughtered at 15 months of age, which is higher than the mean daily gain of 0.95 kg in the population. Probiotics, hormones and vaccines were not used, and antibiotics were only used for treating illness. The present study indicates many advantages and few problems when dairy calves are penned together with the cows and allowed natural feeding up to 6–8 weeks of age. This production system was easy to manage, preferred by the farmer, and may satisfy the public concern regarding the practice of immediate separation of cow and calf in commercial milk production.
Elkjær, Karina; Labouriau, Rodrigo; Ancker, Marie-Louise; Gustafsson, Hans; Callesen, Henrik
A detailed study of 398,237 lactations of Danish Holstein dairy cows was undertaken. The objective was to investigate the information gained by evaluating vaginal discharge in cows from 5 to 19 days post-partum (p.p.) using an ordinal scale from 0 to 9. The study focused on the interval from calving to first insemination (CFI) and the non-return rate 56 days after first insemination (NR56), adjusted for the confounders milk production and body condition score (BCS). For the analyses, BCS was evaluated on the same day that the uterine score was made. Milk production was defined as test-day milk yield in the first month p.p. The study showed that the evaluation of vaginal discharge according to this score system permitted ranking of cows according to CFI and NR56, i.e. an increasing uterine score was associated with a significantly longer time from calving to first insemination and significantly reduced the probability of success of the first insemination. Reproductive success was already affected if the uterine score had reached 4 (i.e. before the discharge smelled abnormally). The negative effect on CFI and NR56 increased as the uterine score increased, which suggested that the uterine scoring system was a useful guide to dairy producers. Copyright © 2013 Elsevier Ltd. All rights reserved.
Silva, T V; Lima, F S; Thatcher, W W; Santos, J E P
The objectives were to evaluate the effects of synchronizing estrus and ovulation to implement a timed artificial insemination (AI) at first insemination on reproductive performance and cost per pregnancy in dairy heifers. Six hundred eleven Holsteins heifers at approximately 400 d of age from 3 farms were enrolled in the study. Six days before moving to the breeding pens, heifers were allocated randomly to AI after detected estrus from study d 0 to 84 (CON, n=306), or to timed AI for first AI followed by detected estrus for the remainder of the 84-d study (TAI, n=305). Heifers receiving TAI were enrolled in the 5-d timed AI protocol on study d -6 (d -6, GnRH and a progesterone insert; d -1, PGF2α and insert removal; d 0, PGF2α; d 2, GnRH + AI), and they were allowed to be bred the day before scheduled timed AI if detected in estrus. Starting on study d 0, estrus was detected daily. Heifers in estrus were inseminated on the same morning as detected estrus. Control heifers not inseminated by study d 7 received PGF2α and this treatment was repeated every 2 wk until AI. The study lasted 84 d to allow a period of breeding equivalent to four 21-d estrous cycles. A herd budget accounting for inputs for both treatments was created to determine the cost per pregnancy. Sensitivity analysis compared economic differences between the 2 treatments under different input scenarios when detection of estrus after the first AI varied from 50 to 80%. Interval to first AI was 8 d shorter for TAI than for CON. Pregnancy at first AI did not differ between treatments (CON=58.3 vs. TAI=62.8%). In contrast, TAI increased pregnancy per AI (P/AI) compared with CON in heifers inseminated with sex-sorted semen (CON=31.6 vs. TAI=54.8%). The 21-d cycle insemination rate was greater for TAI (91.4%) than for CON (82.4%), even when evaluated after the first 21 d in the study (CON=68.2 vs. TAI=77.1%). The increased insemination rate improved the 21-d cycle pregnancy rate from 47.9% in CON to 57
Nielsen, Lars Relund; Kristensen, Anders Ringgaard
In a recent paper a hierarchical Markov decision processes (MDP) with finite state and action space was formulated for the dairy cow replacement problem with stage lengths of 1 d. Bayesian updating was used to predict the performance of each cow in the herd and economic decisions were based...... on the prediction. The model can be used to assist the farmer in replacement decisions on a daily basis and is based on daily milk yield measurements that are available in modern milking systems. This talk will present the results of the paper and discuss directions for further research....
London, M L; Bernard, J K; Froetschel, M A; Bertrand, J K; Graves, W M
Three studies were conducted to determine the relationship between dairy heifer growth and placing in the show ring. In the first study, 1,744 commercial dairy heifers (all breeds and crossbred animals) were evaluated to determine effects of growth on placing within Georgia Commercial Dairy Heifer Shows from 2007 to 2010. Birth weights were determined using breed birth weight averages, with crossbreeds being the average of 2 parent breeds. Average daily gains (ADG) were calculated and heifers were given rankings based on placing in show and for age and weight. Data was analyzed using the Spearman correlation calculations in the SAS software (SAS Institute Inc., Cary, NC). Age and ADG were inversely correlated (r=-0.89). Mean ADG for all heifers was determined to be 0.65 kg, below National Research Council recommendations of 0.7 to 0.8 kg. No strong relationship (r=-0.07) was observed between ADG and placing. Heavier heifers within a class showed a small positive relationship (r=0.10) with placing. For study 2, 238 heifers shown at the 2010 Georgia Junior National Livestock Show (Perry, GA) were measured and evaluated for ADG, placing, body weight, age, withers height, hip height, hip width, and jaw width. Height at withers had a moderate relationship (r=0.42) with placing, followed by hip height (r=0.32). A positive relationship (r=0.65) was observed between withers height and hip height. The correlation between weight and placing was determined (r=0.11). Age and ADG had a strong inverse relationship (r=-0.87). Study 3 evaluated 1,489 Holstein heifers shown from 2007 to 2010. Data was analyzed using the Penn State Growth Monitor Spreadsheet Curves. In total, 63.75% did not meet Penn State recommendations for body weight gain. Performance and physical features associated with age indicates that commercial dairy heifers are underfed. The effects of heat stress and high feed costs also play a role. This has economic implications because these animals will likely
Schmidt, Tracy; Kock, Marleen M.; Ehlers, Marthie M.
Staphylococcus aureus is one of the most common etiological agents of contagious bovine mastitis worldwide. The purpose of this study was to genetically characterize a collection of S. aureus isolates (bovine = 146, human = 12) recovered from cases of bovine mastitis and nasal swabs of close human contacts in the dairy environment. Isolates were screened for a combination of clinically significant antimicrobial and virulence gene markers whilst the molecular epidemiology of these isolates and possible inter-species host transmission was investigated using a combination of genotyping techniques. None of the isolates under evaluation tested positive for methicillin or vancomycin resistance encoding genes. Twenty seven percent of the bovine S. aureus isolates tested positive for one or more of the pyrogenic toxin superantigen (PTSAg) genes with the sec and sell genes predominating. Comparatively, 83% of the human S. aureus isolates tested positive for one or more PTSAg genes with a greater variety of genes being detected. Genomic DNA macrorestriction followed by pulsed-field gel electrophoresis (PFGE) of the bovine isolates generated 58 electrophoretic patterns which grouped into 10 pulsotypes at an 80% similarity level. The majority of the bovine isolates, 93.2% (136/146), clustered into four major pulsotypes. Seven sequence types (ST) were identified among the representative bovine S. aureus isolates genotyped, including: ST8 (CC8), ST97 (CC97), ST351 (CC705), ST352 (CC97), ST508 (CC45), ST2992 (CC97) and a novel sequence type, ST3538 (CC97). Based on PFGE analysis, greater genetic diversity was observed among the human S. aureus isolates. Bovine and human isolates from three sampling sites clustered together and were genotypically indistinguishable. Two of the isolates, ST97 and ST352 belong to the common bovine lineage CC97, and their isolation from close human contacts suggests zoonotic transfer. In the context of this study, the third isolate, ST8 (CC8), is
Full Text Available To utilize locally available feed resources with livestock production in hot climates, dried sardines were incorporated into diets for lactating dairy cows. Fourteen Holstein and 13 Australian Milk Zebu multiparous cows were used in a 70-day continuous feeding experiment. lsonitrogenous and isoenergetic diets containing either soybean meal or dried sardines (supplied 40% of dietary crude protein were fed ad - libitum. Comparisons between diets were made during the 7-week experimental period. The experiment was conducted as a 2 x 2 factorial arrangement of treatment, with diet and breed as main factors. Ruminal pH, ammonia N, total and individual volatile fatty acids concentrations were not altered by the feeding of dried sardines. Intakes of dry matter, energy, crude protein, and acid detergent fiber were lower (P0.05 in Holstein cows fed dried sardines than those fed the control diet (16.2 vs 15.1 kg/d. Feeding of dried sardines did not affect milk composition and compositional yields. Milk production was higher (P<0.01 in Holstein than Australian Milk Zebu cows. Effect of diet and breed interaction on milk production was significant (P<0.01 . Potential of feeding marine proteins may be higher for higher milk producers (Holstein than lower producers (Australian Milk Zebu. Reproduction parameters, body condition scores, and heat-stress associated parameters were not affected by the feeding of dried sardines. This study suggests that dried sardines could be incorporated into diets of lactating dairy cows without affecting milk production.
Geraldo Márcio da Costa
Full Text Available O objetivo deste trabalho foi estudar a freqüência de infecções intramamárias ocasionadas por leveduras a partir de amostras de leite (n=1710 coletadas em 40 rebanhos leiteiros do Estado de Minas Gerais. Cinqüenta e seis estirpes de leveduras do gênero Candida e uma linhagem de Trichosporon loubieri foram isoladas. Candida albicans foi a espécie dominante (28,1% das cepas, seguida por Candida parapsilosis (19,3%, Candida catenulata (14,0%, Candida glabrata (14,0% e Candida tropicalis (8,8%. Infecções mistas foram detectadas em 29,8% das vacas levedura-positivas. Amostras positivas para leveduras foram predominantemente obtidas (84% de vacas com mastite subclínica. A baixa taxa de isolamento de leveduras sugere que estes microrganismos não são relevantes para mastite bovina na região estudada.The objective of this study was to report the frequency of intramammary infections by yeasts, in Minas Gerais State, from milk samples (n = 1710 collected in 40 dairy herds. Fifty six yeast strains of the genus Candida and one strain of Trichosporon loubieri were isolated. Candida albicans was the dominant species (28.1% of the strains, followed by Candida parapsilosis (19.3%, Candida catenulata (14.0%, Candida glabrata (14.0%, Candida tropicalis (8.8%. Mixed infections were detected in 29.8% of yeast-positive cows. The yeast infection was more frequent (84% in cows with subclinical mastitis. The low rate of isolation of yeasts suggests that these microorganisms are not relevant to bovine mastitis in the studied region.
Taye, Messele; Belihu, Kelay; Bekana, Merga; Sheferaw, Desie
This study was conducted to assess the impact of tsetse and trypanosomosis control measures on cattle herd size and composition, herd dynamics, and milk yield in Wolaita and Gamogofa Zones, southern Ethiopia. The study showed that the average number of cattle herd size in tsetse challenged areas was significantly higher than those in tsetse-controlled areas. The number of non-pregnant dry cows, bulls and oxen were significantly higher in tsetse challenged areas than the other two study areas. The rate of cattle addition to and disposal from the herd were significantly higher in tsetse challenged areas. Cows in Southern Tsetse Eradication Project (STEP) and community tsetse controlled areas were able to give 26-27 %, 25-29 % and 17-21 % more daily milk yield at the beginning, middle and end of lactation, respectively, than those in tsetse-challenged areas. In addition, cows in STEP and community tsetse controlled areas had lactation length longer by 1.20 to 1.35 months; age at first calving was shorter by 5.30 to 5.10 months; and calving interval was shorter by 4.20 to 3.20 months than cows in tsetse-challenged area, respectively. Hence, tsetse and trypanosomosis control both by the community and project would play key role in the improvement of cattle productivity.
Maquivar, M G; Barragan, A A; Velez, J S; Bothe, H; Schuenemann, G M
The objectives of the study were to assess responses to treatments (clinical cure and resumption of estrous cycles) of cows with purulent vaginal discharge (PVD) that received intrauterine infusion of a hypertonic solution of 50% dextrose (DEX) or untreated control (CON) cows and the subsequent pregnancy per artificial insemination (PAI) in cows with and without PVD. Cows (n=2,852) from 2 dairy herds were screened for PVD using the gloved hand technique at exam 1 [26±3 d in milk (DIM)]. Cows with vaginal discharge scores of 2 or 3 (0-3 scale) were stratified by parity and randomly allocated into 1 of 2 treatment groups: (1) intrauterine infusion (~200 mL) of 50% DEX solution (n=456), or (2) untreated control animals (CON, n=491). Fourteen days posttherapy (40±3 DIM), cows with PVD were re-examined at exam 2 (40±3 DIM) to assess the response to treatments. All cows were subjected to the same reproductive program, which consisted of estrus detection twice daily (using tail chalking and visual observation) for the first 5 artificial inseminations; then, open lactating cows were turned out with bulls. Cows displaying signs of standing estrus underwent AI and no reproductive hormones were used. Pregnancy diagnosis (PD) was performed via transrectal palpation at 40±3 d post-AI. The risk of culling within 14 d posttherapy was not different among treatment groups. Cows with PVD had greater cervical diameter at exam 1 and decreased PAI compared with cows without PVD. Treatment with DEX increased the proportion of cows with clear vaginal discharge (clinical cure) and cyclicity 14 d posttherapy compared with CON cows. Pregnancy per AI for DEX (29.2±2%) cows was significantly greater than that for CON (22.5±2%) cows. Cows without PVD had a greater proportion of cycling cows (65.6%) and PAI (37%) with reduced pregnancy losses (5.7%) compared with DEX or CON cows. The use of intrauterine DEX alone improved reproductive performance of cows with PVD. Copyright © 2015
Robinson, A L; Timms, L L; Stalder, K J; Tyler, H D
when used within 30min of birth. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Zom, R.L.G.; Schooten, van H.A.; Laar, van H.
A randomized block design experiment was conducted to evaluate the effects of two contrasting silage maize hybrids (DD: dry down vs. SG: stay green) harvested at 33% dry matter (DM) on in situ degradation and dairy cow performance. Thirty-eight Red-HF cows were assigned to two silage treatments and
Jorritsma, R.; Wensing, T.; Kruip, T.A.M.; Vos, P.L.A.M.; Noordhuizen, J.P.T.M.
This review addresses the suggestion that the decline in dairy reproductive performance, as increasingly observed these days, may be due to a hampered process of metabolic adaptation in early lactating cows. In our opinion, adaptation to the negative energy balance is a gradual process. Because
Francoz, D; Buczinski, S; Bélanger, A M; Forté, G; Labrecque, O; Tremblay, D; Wellemans, V; Dubuc, J
Bovine respiratory disease (BRD) is 1 of the 2 most important causes of morbidity and mortality in dairy calves. Surprisingly, field data are scant concerning the prevalence of respiratory pathogens involved in BRD in preweaned dairy calves, especially in small herds. To identify the main respiratory pathogens isolated from calves in Québec dairy herds with a high incidence of BRD, and to determine if there is an association between the presence of these pathogens and clinical signs of pneumonia, lung consolidation, or average daily gain. Cross-sectional study using a convenience sample of 95 preweaned dairy calves from 11 dairy herds. At enrollment, calves were weighed, clinically examined, swabbed (nasal and nasopharyngeal), and lung ultrasonography was performed. One month later, all calves were reweighed. Twenty-two calves had clinical BRD and 49 had ultrasonographic evidence of lung consolidation. Pasteurella multocida, Mannheimia haemolytica, and Histophilus somni were isolated in 54, 17, and 12 calves, respectively. Mycoplasma bovis was identified by PCR testing or culture in 19 calves, and 78 calves were found to be positive for Mycoplasma spp. Bovine coronavirus was detected in 38 calves and bovine respiratory syncytial virus in 1. Only the presence of M. bovis was associated with higher odds of clinical signs, lung consolidation, and lower average daily gain. Results suggested that nasopharyngeal carriage of M. bovis was detrimental to health and growth of dairy calves in small herds with a high incidence of BRD. Copyright © 2015 by the American College of Veterinary Internal Medicine.
O'Brien, D; Hennessy, T; Moran, B; Shalloo, L
Mitigating greenhouse gas (GHG) emissions per unit of milk or the carbon footprint (CF) of milk is a key issue for the European dairy sector given rising concerns over the potential adverse effects of climate change. Several strategies are available to mitigate GHG emissions, but producing milk with a low CF does not necessarily imply that a dairy farm is economically viable. Therefore, to understand the relationship between the CF of milk and dairy farm economic performance, the farm accountancy network database of a European Union nation (Ireland) was applied to a GHG emission model. The method used to quantify GHG emissions was life cycle assessment (LCA), which was independently certified to comply with the British standard for LCA. The model calculated annual on- and off-farm GHG emissions from imported inputs (e.g., electricity) up to the point milk was sold from the farm in CO2-equivalent (CO2-eq). Annual GHG emissions computed using LCA were allocated to milk based on the economic value of dairy farm products and expressed per kilogram of fat- and protein-corrected milk (FPCM). The results showed for a nationally representative sample of 221 grass-based Irish dairy farms in 2012 that gross profit averaged € 0.18/L of milk and € 1,758/ha and gross income was € 40,899/labor unit. Net profit averaged € 0.08/L of milk and € 750/ha and net income averaged € 18,125/labor unit. However, significant variability was noted in farm performance across each financial output measure. For instance, net margin per hectare of the top one-third of farms was 6.5 times higher than the bottom third. Financial performance measures were inversely correlated with the CF of milk, which averaged 1.20 kg of CO2-eq/kg of FPCM but ranged from 0.60 to 2.13 kg of CO2-eq/kg of FPCM. Partial least squares regression analysis of correlations between financial and environmental performance indicated that extending the length of the grazing season and increasing milk production
Herd-level prevalence and associated risk factors for Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhoea virus in commercial dairy and beef cattle in eastern, northern and northeastern China.
Sun, Wu-Wen; Meng, Qing-Feng; Cong, Wei; Shan, Xiao-Feng; Wang, Chun-Feng; Qian, Ai-Dong
Although the seroprevalence of Toxoplasma gondii, Neospora caninum, Chlamydia abortus and bovine viral diarrhea virus infection in cattle have been reported in some areas in China, most of them were conducted with small number of cattle samples and very limited districts and neglected the assessment of herd management factors associated with herd-level prevalence of these pathogen infections. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the animal-level and herd-level seroprevalence and identify herd-level risk factors associated with these pathogen infections in 4487 cattle from 134 herds in five provinces (Heilongjiang, Jilin, Liaoning, Shandong, Hebei) and Inner Mongolia Autonomous Region of China. At animal level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and bovine viral diarrhoea virus (BVDV) was 10.48, 17.14, 11.92 and 50.10%, respectively. At herd level, the true prevalence of antibodies against T. gondii, N. caninum, C. abortus and BVDV was 27.16, 29.10, 37.31 and 40.30%, respectively. Multivariate analysis of these characteristics showed that source of water and presence of felids were significantly associated with T. gondii infection in the studied cattle herds. Source of water was significantly associated with N. caninum infection in the studied cattle herds. While herd size and management system were significantly associated with BVDV infection in the studied cattle herds, this is the first report of herd-level prevalence and associated risk factors of T. gondii, N. caninum, C. abortus and BVDV infection in cattle in China.
Bach, A; Terré, M; Pinto, A
, LMR grow more than HMR calves, overcoming the difference in BW at preweaning. As a result, with the weaning scheme followed herein, providing more milk does not ensure greater performance; no differences are obtained in BW at weaning and at 228 d of life. Also, based on solid feed consumption patterns seen in this study, we determined that the optimum age to reduce MR allowances and foster solid feed intake is around 45 d of age. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Dash, Soumya; Chakravarty, A K; Singh, Avtar; Upadhyay, Arpan; Singh, Manvendra; Yousuf, Saleem
Heat stress has adverse effects on the reproductive performances of dairy cattle and buffaloes. The dairy sector is a more vulnerable to global warming and climate change. The temperature humidity index (THI) is the widely used index to measure the magnitude of heat stress in animals. The objective of this paper was to assess the decline in performances of reproductive traits such as service period, conception rate and pregnancy rate of dairy cattle and buffaloes with respect to increase in THI. The review stated that service period in cattle is affected by season of calving for which cows calved in summer had the longest service period. The conception rate and pregnancy rate in dairy cattle were found decreased above THI 72 while a significant decline in reproductive performances of buffaloes was observed above threshold THI 75. The non-heat stress zone (HSZ) (October to March) is favorable for optimum reproductive performance, while fertility is depressed in HSZ (April to September) and critical HSZ (CHSZ) (May and June). Heat stress in animals has been associated with reduced fertility through its deleterious impact on oocyte maturation and early embryo development. The management strategies viz., nutrition modification, environment modification and timed artificial insemination protocol are to be strictly operated to ameliorate the adverse effects of heat stress in cattle and buffaloes during CHSZ to improve their fertility. The identification of genes associated with heat tolerance, its incorporation into breeding program and the inclusion of THI covariate effects in selection index should be targeted for genetic evaluation of dairy animals in the hot climate.
Caulfield, H. John
There are two extremes in optimization with little ground between them. They are local optimization and global optimization. Local optimization is normally very fast, but the optimum it finds may be far from the best (global) optimum. Global optimization is very slow, but it gives the best optimum- at least in principle. Using mammal herds as rough models, we suggest a new evolutionary method that has aspects of both and achieves intermediate results most of the time: faster-than-global convergence with better-than- local performance.
Ettema, Jehan Frans; Østergaard, Søren; Kristensen, Anders Ringgaard
Cross sectional data on the prevalence of claw and (inter) digital skin diseases on 4854 Holstein Friesian cows in 50 Danish dairy herds was used in a Bayesian network to create herd specific probability distributions for the presence of lameness causing diseases. Parity and lactation stage...... probabilities and random herd effects are used to formulate cow-level probability distributions of disease presence in a specific Danish dairy herd. By step-wise inclusion of information on cow- and herd-level risk factors, lameness prevalence and clinical diagnosis of diseases on cows in the herd, the Bayesian...
Hoorfar, Jeffrey; Bitsch, V.
A total of 2585 serum samples from 62 dairy herds located in four different regions of Denmark were tested in an O-antigen (0:1,4,5,12)-based ELISA for the detection of antibodies against Salmonella typhimurium. Ten closed herds from an island with no reported occurrence of salmonellosis for seve......A total of 2585 serum samples from 62 dairy herds located in four different regions of Denmark were tested in an O-antigen (0:1,4,5,12)-based ELISA for the detection of antibodies against Salmonella typhimurium. Ten closed herds from an island with no reported occurrence of salmonellosis...... for several years, and 12 herds from a salmonella enzootic area which had had clinical outbreaks of S typhimurium were used to define a herd ELISA cut-off value. When herds with at least 5 per cent of the serum samples having an optical density of >0.5 were considered ELISA-positive, all 10 herds from...... the salmonellosis-free island were ELISA-negative, and all but one of the 12 S typhimurium-infected herds were ELISA-positive, which resulted in a herd test sensitivity of 0.92 and herd test specificity of 1.0. Eleven of the 12 S typhimurium-infected herds were negative in a blocking ELISA based on a monoclonal...
Runciman, D J; Anderson, G A; Malmo, J
Part 1: compare the use of a Metricheck device (a stainless steel probe with a semi-spherical rubber cup attached at one end) to sample the contents of the anterior vagina with a vaginal speculum examination for the diagnosis of pus in the vagina of postpartum dairy cows and to investigate the association of that pus with reproductive performance. Part 2: assess the effect of a single intrauterine infusion of 500 mg cephapirin in cows diagnosed with vaginal purulent or mucopurulent discharge 7 to 28 days after calving on reproductive performance. Six herds were visited fortnightly to examine cows that had calved between 7 and 28 days (n = 423) with both the Metricheck device and a vaginal speculum to score, by each method, the vaginal discharge from 0 (clear or absent) to 3 (purulent) for each animal included in the study. Half of the cows that had a positive discharge score (1 to 3 by either examination method) were then treated with an intrauterine infusion of 500 mg of cephapirin. The relationship between Metricheck score, vaginoscopy score, treatment and reproductive performance was assessed. There was a substantial measure of agreement between each method when scores were analysed by status. Cows that were positive with either method had inferior reproductive performance compared with cows with a score of zero. Treatment of cows diagnosed with a purulent or mucopurulent discharge with intrauterine cephapirin improved reproductive performance in both the vaginoscopy and Metricheck groups.
Santos, J E P; Bisinotto, R S; Ribeiro, E S; Lima, F S; Greco, L F; Staples, C R; Thatcher, W W
The establishment and maintenance of pregnancy in lactating dairy cows is a complex biological event that is influenced by a multitude of factors, from the reproductive biology of the cow to managerial aspects of the dairy farm. It is often mentioned in the scientific literature that fertility in dairy cows has declined concurrent with major advances in milk production. Some of this decline is attributed to the negative genetic correlation between milk production and reproduction. In the United States, yearly production per cow has increased steadily at a rate of 1.3% in the last decade and it is likely that this trend will continue in the years to come. At this rate, the average cow in the United States will be producing over 14 tons of milk per year in 2050 and technologies will have to be developed to allow these cows to reproduce to maintain the sustainability of dairy production. Despite high production, it is not uncommon for dairy herds with rolling herd averages for milk yield above 11,000 kg to overcome the challenges of reproduction and obtain satisfactory reproductive performance. Among other things, those herds have been able to mitigate some of the mechanisms that suppress reproduction in dairy cows such as extended postpartum anovulatory period, poor estrous detection, low pregnancy per insemination and, to a lesser extent, the high pregnancy loss. The success of those farms comes from an integrated approach to fertility that includes adequate cow comfort, elaborated transition cow management and nutrition, aggressive postpartum health monitoring program with preventative and curative measures to mitigate the negative effects of diseases on reproduction, and a sound reproductive program that includes manipulation of the ovarian cycle to allow for increased insemination rate. More recently, introduction of fertility traits in selection programs have created new opportunities for improved reproduction without neglecting economically important production
Murphy, T W; Berger, Y M; Holman, P W; Baldin, M; Burgett, R L; Thomas, D L
The Spooner Agricultural Research Station operated the only dairy sheep research flock in North America through 2016. The original nondairy ewe flock was "bred up" to a crossbred dairy flock through the use of rams and semen of the East Friesian (EF) and Lacaune (LA) dairy breeds. The objective of this study was to determine the environmental and nonadditive genetic effects that influence performance of dairy ewes. The traits analyzed were 180 d adjusted milk (180d MY), fat (180d FY), and protein (180d PY) yields, percentage fat (%F) and protein (%P) in milk, lactation average somatic cell score (LSCS), and number of lambs born per ewe lambing (NLB). The univariate repeatability models included the fixed effects of year of lambing, age, weaning system (except for the trait of NLB), individual breed composition, and individual retained heterosis along with the random additive genetic, permanent environmental, and residual effects. Estimates of heritability were moderate for 180d MY (0.32 ± 0.04), 180d FY (0.26 ± 0.04), and 180d PY (0.29 ± 0.04), high for %F (0.54 ± 0.04) and %P (0.61 ± 0.04), and low for LSCS (0.12 ± 0.03) and NLB (0.08 ± 0.02). Ewes that reared their lambs had lower ( ewes that had their lambs removed shortly after parturition. Relative to nondairy breeding, EF and LA breeding had positive ( ewes were predicted to have lower ( ewes. Purebred LA ewes were predicted to have a higher ( ewes. Purebred EF ewes were expected to be more ( ewes. Individual retained heterosis had a favorable ( ewe performance are important for dairy sheep producers to make more informed husbandry and breeding decisions.
Full Text Available An epidemiological study was carried out on 2823 cows from 34 dairy herds from Goiania in the State of Goias-Brazil during 2001 to 2002. The pregnancy rate was 47.8%. In 1473 non-pregnant cows, causes of reproductive failure problems were sought. The most prevalent uterine infection was endometritis (17.0%. Uterine disorders such as partial hypoplasia of the genital system (0.04%, macerate fetus (0.01%, adhesion of ovaries (0.04%, stillbirth (0.04%, retained placenta (0.01%, cervix inflammation (0.6% and abortion (0.88% also were found. Uterine swabs were collected aseptically for microbiological culture. Gram positives cocci (41.3% and Gram negatives rods (52.6% were found, and Staphylococcus aureus and Escherichia coli were the most prevalent pathogens. Susceptibility patterns of microorganisms suggested the use of chloramphenicol, gentamicin and neomycin for antimicrobial therapy.No período de março 2001 a julho 2002 foram estudadas 2823 fêmeas bovinas, em idade de reprodução, mestiças das raças Holandesa e Gir, pertencentes a 34 propriedades da bacia leiteira de Goiânia. A taxa de prenhez foi 47,8%. Entre os animais não gestantes (n= 1473, 17% apresentaram alterações inflamatórias do útero. Outras anormalidades encontradas foram: aplasia parcial do sistema genital (0,04%, feto macerado (0,01%, ovário aderido (0,04%. Casos de natimortalidade (0,04%, retenção placentária (0,01% e cervicite (0,6% e taxas de abortos (0,88% também foram registrados. Cocos Gram positivos (41,3% e bastonetes Gram negativos (52,6% foram os microrganismos mais isolados, sendo Staphylococcus aureus e Escherichia coli os principais patógenos encontrados nas infeccções uterinas. Testes in vitro mostraram que esses microrganismos apresentaram maior susceptibilidade frente ao cloranfenicol, à gentamicina e à neomicina.
Larsen, J W A; Webb Ware, J K; Kluver, P
To describe the epidemiology of bovine Johne's disease (BJD) in beef herds in Australia. Retrospective survey of beef herds detected with BJD between 1991 and 2006. Information about the management and physical characteristics of affected herds, index and clinical cases, testing and control programs, and attitudes to BJD were collated from existing data and personal interviews of herd owners or managers. Herds were excluded if they contained fewer than 30 breeding cows or operated as a dairy farm. Records from 109 herds demonstrated the first detected ('index') case was 3.4-fold more likely to be a beef rather than dairy breed. However, further analysis revealed association with dairy cattle was an important risk factor for introducing BJD. Index cases were most likely detected by veterinarians investigating clinical cases of scouring or ill-thrifty animals during winter, particularly bulls or aged cows. Most herds with clinical BJD had only a single case, with only one high prevalence herd detected in the survey group. Over the period of observation, test and cull programs did not eradicate BJD unless combined with culling of known high-risk animals, but removal of high-risk cattle by partial or total destocking generally restored the trading status of affected herds. Excluding cattle with dairy contact from beef herds, ensuring more effective farm biosecurity, promptly seeking veterinary advice regarding scouring cattle and sourcing replacement cattle from demonstrably low-risk herds, such as CattleMAP and 'Beef Only' herds, are simple strategies that should reduce the risk of introducing BJD infection into beef herds. © 2012 The Authors. Australian Veterinary Journal © 2012 Australian Veterinary Association.
Giuliodori, M J; Magnasco, M; Magnasco, R P; Lacau-Mengido, I M; de la Sota, R L
The objectives of this study were to assess the association of a 4-point scale of vaginal discharge score (VDS) with time to pregnancy to define criteria for a practical case of purulent vaginal discharge (PVD) in dairy cows, to test the risk factors for PVD, and, finally, the effect of a dose of PGF 2α on cure and reproductive performance. In experiment 1, grazing Holstein cows (n = 2,414) had their vaginal discharge scored at ∼32 d in milk (DIM) on a 4-point scale, the effect of VDS on the hazard of pregnancy by 300 DIM was then assessed to derive a case definition of PVD. Risk factors for PVD and self-cure were also assessed. In experiment 2, grazing Holstein cows (n = 6,326) from 5 herds were checked for PVD at ∼30 DIM. Cows with PVD were assigned to receive one dose of 500 μg of PGF 2α analog (Cloprostenol; Ciclase, Syntex SA, Buenos Aires, Argentina) per cow (odd ear tag number) or to remain untreated (even tag number). Cure was declared if cows presented clear normal vaginal discharge (VDS-0) at visit 2 (∼62 DIM). Data were analyzed with Cox's regression and mixed logistic models. In experiment 1, cows with VDS ≥1 had lower hazard of pregnancy and longer calving to pregnancy interval than cows with VDS-0. This finding was not affected by the time at which the diagnosis was performed. Therefore, a cow ≥21 DIM and having VDS ≥1 was used to define a case of PVD. The odds of PVD were greater in primiparous cows compared with multiparous, in cows with abnormal calving compared with those with normal calving, and in those losing BCS peripartum. In experiment 2, PGF 2α treatment tended to slightly increase the hazard of pregnancy (adjusted hazard ratio = 1.13). Conversely, PGF 2α had no effect on the odds of cure of PVD [adjusted odds ratio (AOR) = 1.19], pregnancy at first service (AOR = 1.03), or pregnancy by 100 DIM (AOR = 0.89) or 200 DIM (AOR = 1.27). In conclusion, cows with VDS ≥1 can be considered to have PVD because of their lower hazard
Della Riva, A.; Kristensen, Troels; De Marchi1, M.
. The results show 0.80 kg CO2eq/kg ECM in JE herd, while 0.96 kg CO2eq/kg ECM in HF herd. The main differences were due to the level of dry matter intake, milk yield and fertility traits. Indeed, JE herd showed a lower milk yield than HF herd, a lower DMI and better fertility, determining less production......Aim of the present study was to estimate the carbon footprint (CF) of milk production at farm gate considering two dairy cattle breeds, Holstein Friesian (HF) and Jersey (JE). Using Italian inventory data the emissions of CO2eq per kg ECM for dairy herds of HF and JE breed were estimated...... and consumption of feed and less replacement animals in the herd....
Maria do Carmo Pessôa Silva
Full Text Available Bovine tuberculosis is a zoonosis with worldwide distribution. Its control has a direct impact on public health and livestock production. This study estimated the prevalence of infected herds and adult bovines and evaluated risk factors associated with the presence of tuberculosis within herds in the state of Paraná. The state was divided in seven livestock regions and independent sampling was performed. A total of 1,419 farms were sampled and 16,045 animals were tested using the intradermal comparative cervical tuberculin diagnostic test. The apparent and estimated prevalence rates in farms and adult bovine animals were 2.15% (95% CI: 1.31-3.00 and 0.42% (95% CI: 0.04-0.81, respectively. It was not possible to state with 95% confidence that the disease prevalence in any region was significantly different from that in other regions. There were no positive animals in the western region, and the prevalence of positive herds and animals in the other regions ranged from 1.03% to 3.89% and 0.17% to 1.08%, respectively. The logistic regression model identified larger herd size (OR = 2.4 and mechanical cmilking (OR = 5.18 as risk factors associated with the presence of bovine tuberculosis. The combination of low prevalence with risk factors associated to larger herds and more intensive dairy farming, renders the state of Paraná a good candidate for the implementation of industry-based free-herd accreditation schemes and makes a case for planning risk-based surveillance targeted at major dairy basins.
Roelofs, J B; Krijnen, C; van Erp-van der Kooij, E
When the daily routine of a cow is disturbed, it may have a detrimental effect on the performance of activity meters to detect estrus. It is possible that during the pasture period, the daily routine of cows is disturbed, adversely affecting the performance of activity meters to detect estrus which does not happen when the cows are housed indoors. The objective of this study was to investigate whether housing conditions (pasture or indoor) affected the performance of activity meters to detect estrus in dairy cows. In this research, two types of activity meters were used, an activity meter attached to the leg and one mounted on the neck. Cows of two different herds were equipped with the Smarttag Leg and the Smarttag Neck (Nedap livestock management, Groenlo, the Netherlands). The study began during the pasture period (September) and ended during the indoor period (January). The pasture period ended at the beginning of November. So, about two months of pasture period and two months of indoor period were studied. Milk samples were collected twice a week during the morning milking and true estrus was determined by milk progesterone concentrations. In total, the dataset consisted of 95 true estrous periods and 1992 true non-estrous days of 56 cows for the pasture period and 138 true estrous periods and 3164 true non-estrous days of 65 cows for the indoor period. Overall, no differences in sensitivity, positive predictive value (PPV) and specificity were found between the pasture and indoor period for both types of sensors. There was also no difference in the performance between leg and neck activity meters. Sensitivity was between 76 and 82%, PPV was between 87 and 92% and specificity was between 99 and 100%. In conclusion, the sensitivity, PPV and specificity did not differ between the pasture and indoor period. This means that, in our study, the performance of both types of activity meters to detect estrus is not affected by housing conditions. Copyright © 2017
Full Text Available The main objective of this study is to assess dairy cattle reproduction performances from artificial insemination (Al database, using inseminators' records from 1992 to 1998, in three Al circuits established in Settat province in Morocco. Simultaneously a field survey was conducted in the same region, from January to April 1999, to determine main structural parameters of dairy farms which influence Al. Data set analysis has shown an increase in total number of Al performed from an average of 160 to 640 per circuit. Average conception rate was 48.1 %, with a continuous increase from 44.3 to 58.6 %, despite growing number of performed Al. Statistical analysis reveal a significant variation of conception rate between years, in agreement with previous works on cattle reproduction performances in harsh conditions. Mean calving interval was 404.8 days. It was significantly different between circuits (P <0.05. This resuit was explained by Al history in the three circuits (date of implementation and by their structural characteristics (number of cows and length in km. The overall improvement of Al activity (more Al performed and better conception rate could be explained by a greater inseminators' adaptation to their working environment, combined to the progressive elimination of farms with poor dairy cattle reproduction management. This trend was confirmed by discriminant analysis of field survey results, as cattle breeders with real specialisation in milk production (more than 65 % of total land devoted to forages and few sheep have been found to be fervent Al demanders, whereas farms with more interest in cereals and sheep often stop Al. Those observations show that a continuous Al programs evaluation is urgent, in order to select dairy breeders which are really interested in that technique and to avoid the dissipation of the inseminators limited time and resources.
Derks, Marjolein; van Woudenbergh, Bram; Boender, Monique; Kremer, Wim; van Werven, Tine; Hogeveen, Henk
In providing advice on herd health, veterinarians need to be aware of farmers' goals and priorities. To determine the level of awareness, 29 veterinarians from 15 practices completed questionnaires during visits to dairy farms within the scope of veterinary herd health management (VHHM) programmes. The farmers (n=30) were asked to complete a questionnaire and their discussions with the veterinarian were recorded using a voice recorder. Herd performance goals were set by the farmer and veterinarian in 24% of cases. Veterinarians who did not set goals indicated that they and the farmer 'intuitively knew' what each wanted to achieve, and that the setting of performance goals was considered 'too formal'. Veterinarians often could not identify a farmer's main goal, and typically found milk production and nutrition significantly more important (Pveterinarians did not actively seek to identify farmers' goals or problems, suggest a co-operative strategy or summarise any advice given. The findings of this survey suggest that veterinarians need to focus more on goal setting, since awareness of goals and priorities is important for both communication and compliance with advice given. The needs of farmers with respect to herd health should also be more actively sought by veterinarians as the findings indicate that most farmers do not readily volunteer such information. Copyright © 2013. Published by Elsevier Ltd.
Tegtmeier, C.; Stryhn, H.; Uttenthal, Åse
for antibodies was performed using a blocking ELISA detecting antibodies to pestivirus. Data from 815 herds were analysed statistically by the maximum likelihood method in a multinomial model. The estimated herd prevalence was 0.083 and the estimated individual prevalence within the positive herds was 0...
Carlos Augusto B. de Carvalho
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.
Young, K E; Garza, V; Snowden, K; Dobson, R J; Powell, D; Craig, T M
Diversity of parasite populations was compared between two herds of horses, one a regularly treated herd the other a feral herd which has bad no anthelmintic treatment for at least 25 years. Eggs obtained from fecal samples of both herds were tested for anthelmintic resistance by use of an in-vitro larval hatch/development assay (LDA), DrenchRite. A fecal egg reduction test was also performed with the domesticated herd using fenbendazole, pyrantel pamoate and ivermectin. Cyathostomes were the predominant group of worms present in both herds. Trichostrongylus axei was seen in both herds, but Strongylus equinus, Strongylus vulgaris, Gyalocephalus capitatus, Poteriostomum spp. and Strongyloides westeri were only found in the feral horses. Larvae of Strongylus edentatus were found in a single domesticated horse. Fecal egg reduction tests with the domesticated herd showed a 32% egg count reduction for fenbendazole, a 93% reduction with pyrantel, and a 99% reduction with ivermectin. From the LDA, anthelmintic resistance was evaluated by determining the resistance ratio of the domesticated herd compared with the feral herd. For benzimidazoles in the domesticated herd, 45% of the cyathostome population was 9.4 times more tolerant than the feral herd's parasite population. The parasite population in the domesticated herd was 1.5 times more tolerant to Levamisole, and 1.7 times more tolerant to the benzimidazole/levamisole combination than the parasite population within the feral herd. 9% of the parasite population in the domesticated herd was 90 times more tolerant to avermectins than the feral herd's parasite population, even though a subpopulation of worms in the feral herd were tolerant to low concentrations of avermectins despite never being previously exposed to this class of anthelmintic.
Wong, Danilo Lo Fo; Dahl, J.; van der Wolf, P.J.
The aim of this study was to assess the probability of detecting Salmonella from pen faecal samples in seropositive classified finishing pig herds. The study involved 77 herds from Denmark (20), The Netherlands (20), Greece (17) and Germany (20). The serological herd status was determined...... by the blood-sampling of 50 finishing pigs. Bacteriological sampling was performed by 20 pen faecal samples per herd. Over-all, 47% of the blood samples had an OD% larger than 10 and 23% larger than 40. Salmonella was isolated from 135 (9.3%) pen faecal samples in 32 herds (42%). Twenty-eight of these herds...... (87.5%) had a within-herd seroprevalence larger than 50% at sample cut-off OD% > 10. In our study, there was an increasing probability of recovering Salmonella with increasing within-herd seroprevalence. However, this was only a moderate correlation. A correlation coefficient of 0.62 was found between...
Walsh, Robert B; Kelton, David F; Hietala, Sharon K; Duffield, Todd F
Serum and milk samples from 1229 cows on 22 Ontario dairy farms were individually tested for antibodies specific for bovine leukosis virus (BLV) and Neospora caninum by enzyme-linked immunosorbent assay (ELISA). Antibodies against BLV were present in 361 serum samples (29.4%) and 369 milk samples (30.0%). Comparing the 2 tests, agreement was almost perfect (k = 0.86; 95% CI = 0.83 to 0.90) and the proportions of samples positive were not significantly different (P = 0.56). Both tests identified the same 3 herds free of bovine leukosis virus. Antibodies against N. caninum were detected in 138 serum samples (11.2%), and 111 milk samples (9.0%). Agreement between the 2 tests was moderate (k = 0.52; 95% CI = 0.43 to 0.59). Four herds were free of neosporosis by the serum test, while 10 herds were negative by the milk test. The ELISA on milk samples facilitates sample collection to classify herds free of BLV; the milk N. caninum ELISA was less reliable in predicting herd-level infection.
Sternberg Lewerin, Susanna
The Swedish Salmonella control programme includes mandatory action if Salmonella is detected in a herd. The aim of this study was to assess the relative value of different strategies for pre-movement testing of cattle. Three fictitious herds were included: dairy, beef and specialised calf-fattening. The yearly risks of introducing Salmonella with and without individual serological or bulk milk testing were assessed as well as the effects of sourcing animals from low-prevalence areas or reducing the number of source herds. The initial risk was highest for the calf-fattening herd and lowest for the beef herd. For the beef and dairy herds, the yearly risk of Salmonella introduction was reduced by about 75% with individual testing. Sourcing animals from low-prevalence areas reduced the risk by >99%. For the calf-fattening herd, the yearly risk was reduced by almost 50% by individual testing or sourcing animals from a maximum of five herds. The method was useful for illustrating effects of risk mitigation when introducing animals into a herd. Sourcing animals from low-risk areas (or herds) is more effective than single testing of individual animals or bulk milk. A comprehensive approach to reduce the risk of introducing Salmonella from source herds is justified. Copyright © 2017 Elsevier Ltd. All rights reserved.
Crossbred cows are the main type of cattle used for milk production on smallholder and medium farms in urban and peri-urban areas of Morogoro Municipality. A study was undertaken on four medium-scale and forty five smallholder farms to investigate the reproductive and productive performance of crossbred maintained ...
To compare growth performance of Brown Swiss calves fed acidified milk replacer (AMR) at 8% of birth weight, 20 newborn calves were reared under a new calf-feeding programme. Body weights, total weight gains and gains in body measurements, feed intake and feed efficiency values determined at different stages of ...
Keshavarzi, Hamideh; Sadeghi-Sefidmazgi, Ali; Kristensen, Anders Ringgaard
Abortions, especially those occurring during late pregnancy, lead to considerable economic losses. To estimate the financial losses related to pregnancy loss, at first the influencing factors on abortion need to be identified. Thus, the objective of this study was to determine and quantify the risk...... for abortion, but due to significant interaction with mastitis it was kept in the final model. In general, it is concluded that inclusion of significant interactions in a risk factor analysis as the present is of paramount importance for a correct quantification of the risk factors for a cow with given...
Full Text Available Sustainability in livestock production system is largely affected by climate change. An imbalance between metabolic heat production inside the animal body and its dissipation to the surroundings results to heat stress (HS under high air temperature and humid climates. The foremost reaction of animals under thermal weather is increases in respiration rate, rectal temperature and heart rate. It directly affect feed intake thereby, reduces growth rate, milk yield, reproductive performance, and even death in extreme cases. Dairy breeds are typically more sensitive to HS than meat breeds, and higher producing animals are, furthermore, susceptible since they generates more metabolic heat. HS suppresses the immune and endocrine system thereby enhances susceptibility of an animal to various diseases. Hence, sustainable dairy farming remains a vast challenge in these changing climatic conditions globally.
Parámetros Genéticos para Algunas Características Productivas y Reproductivas en un Hato Holstein del Oriente Antioqueño, Colombia Genetic Parameters for Some Productive and Reproductive Traits in a Dairy Herd in Eastern Antioquia, Colombia
Katerinne Quiroz Osorio
first and second lactation and some other features related to the overall performance of cows during her life, which have wide importance in dairy cattle. Were analyzed 928 records of lactations of 184 Holstein cows born among the years 1985 to 2006 in a dairy herd in the department of Antioquia. The variance components were estimated by univariate and bivariate maximum likelihood methodology derivative free restricted and the correlations by direct estimation with phenotype information and estimated breeding values. The SAS 9.0 software was used for data editing and statistical analysis MTDFREML software was used for genetic analysis. The age and weight at first service did not have significant effect (P>0.05 on milk production in first and second lactation, neither with the total life production, However the age and weight at first fertile service had an effect highly significant (P<0.01 on production in first lactation. Heritability estimates for age and weight at first service were 0.29 ± 0.184 and 0.04 ± 0.170, age and weight at service fertile ± 0.41 0.195 ± 0.210 and 0.08 respectively.
Delaby, L; Faverdin, P; Michel, G; Disenhaus, C; Peyraud, J L
The dairy farming systems of Western Europe are based on a simple feeding system composed of grazed and preserved grass, maize silage and concentrates in variable proportions. There is, nevertheless, a great diversity of feeding strategies between dairy farms. Over 5 years, we studied the direct and delayed effects of four feeding strategies on the lactation and reproduction performances of Holstein and Normande dairy cows. The four feeding strategies (denoted Hh, Hl, Lh and Ll) correspond to two total mixed rations applied in winter from calving to turnout (maize silage with 30% concentrate or grass silage with 15% concentrate), which were subsequently crossed with two levels of concentrate supplementation at grazing to 210 days. Each year, 72 dairy cows managed in grouped winter calving were assigned to the four strategies. Finally, the results of 325 lactations and 295 inseminated cows were analysed. The four strategies resulted in considerable variation in nutrient intake and, in particular, in differences in concentrates consumed, with values of 1407, 1026, 773 and 392 kg dry matter per cow for strategies Hh, Lh, Hl and Ll, respectively. Total milk production (7567, 7015, 6720 and 6238 kg per cow for treatments Hh, Lh, Hl and Ll, respectively), milk fat content (39.0, 37.1, 40.3 and 38.5 g/kg, respectively), milk protein content (33.0, 31.8, 33.1 and 31.6 g/kg, respectively), and the character of the lactation and body condition curves were all highly sensitive to the strategies applied. While no significant interaction was detected on total lactation yield, the Holstein cows reacted more dramatically to each dietary change at each period, compared with the Normande cows. Winter feeding did not affect the production of milk at pasture whereas, at pasture, the milk from the cows of the H groups in winter was higher in milk fat and protein content. Reproduction performance was unaffected by feeding strategy. The Holstein cows, well fed and producing the most
Meirelles, C.F.; Vitti, D.M.S.S.; Abdalla, A.L.
Reproductive performance and nutritional status were assessed in Holstein cows from two dairy herds in Sao Paulo State, Brazil. In the first herd (good management, G), concentrate was fed individually to cows, complete records were kept, veterinary services were provided as necessary and the standard of husbandry practices was good. In the second herd (fair management, F), veterinary services were used only occasionally, the concentrate fed was divided equally among lactating cows and the standard of husbandry practices was only fair. Haemoglobin, haematocrit, glucose, total protein and phosphorus were measured in blood collected at various times after calving. There were no statistical differences between the blood parameters in the two herds except for inorganic phosphorus which differed significantly between farms (P < 0.01). Only plasma glucose had a significant (P < 0.01) effect on the time required by the animals to initiate post-partum ovarian activity. The proportion of cows ovulating by day 60 was 75% in herd G versus 53% in herd F (P < 0.01); by day 100 the values were 82% in herd G and 70% in herd F (P < 0.01). Calving intervals were 12.7 and 13.2 months for herds G and F respectively, suggesting comparable reproductive efficiency. However, only 1 of the 28 cows in herd G was open more than 365 days after calving, as opposed to 5 of the 30 cows in herd F. When a value of 365 open days was given for these non-pregnant cows, the average days open for the herds were then 123 and 154 days for herds G and F respectively, indicating a decided production advantage in favour of the better managed herd. (author). 16 refs, 1 fig., 2 tabs
X. W. Yi
Full Text Available The objective of the present study was to determine the effects of feeding pelletized broccoli byproducts (PBB on milk yield and milk composition in dairy cows. In Trial 1, an in vitro gas test determined the optimal replacement level of PBB in a concentrate mixture in a mixed substrate with Chinese wild ryegrass hay (50:50, w/w at levels of 0, 10%, 20%, 30%, or 40% (dry matter basis. When the concentrate was replaced by PBB at a level of 20%, no adverse effects were found on the gas volume or its rate constant during ruminal fermentation. In trial 2, 24 lactating cows (days in milk = 170.4±35; milk yield = 30±3 kg/d; body weight = 580 ±13 kg were divided into 12 blocks based on day in milk and milk yield and randomly allocated to two dietary treatments: a basic diet with or without PBB replacing 20% of the concentrate mixture. The feeding trial lasted for 56 days; the first week allowed for adaptation to the diet. The milk composition was analyzed once a week. No significant difference in milk yield was observed between the two groups (23.5 vs 24.2 kg. A significant increase was found in milk fat content in the PBB group (p0.05. These results indicated that PBB could be included in dairy cattle diets at a suitable level to replace concentrate mixture without any adverse effects on dairy performance.
Vagnoni, E; Franca, A; Breedveld, L; Porqueddu, C; Ferrara, R; Duce, P
Although sheep milk production is a significant sector for the European Mediterranean countries, it shows serious competitiveness gaps. Minimizing the ecological impacts of dairy sheep farming systems could represent a key factor for farmers to bridging the gaps in competitiveness of such systems and also obtaining public incentives. However, scarce is the knowledge about the environmental performance of Mediterranean dairy sheep farms. The main objectives of this paper were (i) to compare the environmental impacts of sheep milk production from three dairy farms in Sardinia (Italy), characterized by different input levels, and (ii) to identify the hotspots for improving the environmental performances of each farm, by using a Life Cycle Assessment (LCA) approach. The LCA was conducted using two different assessment methods: Carbon Footprint-IPCC and ReCiPe end-point. The analysis, conducted "from cradle to gate", was based on the functional unit 1 kg of Fat and Protein Corrected Milk (FPCM). The observed trends of the environmental performances of the studied farming systems were similar for both evaluation methods. The GHG emissions revealed a little range of variation (from 2.0 to 2.3 kg CO2-eq per kg of FPCM) with differences between farming systems being not significant. The ReCiPe end-point analysis showed a larger range of values and environmental performances of the low-input farm were significantly different compared to the medium- and high-input farms. In general, enteric methane emissions, field operations, electricity and production of agricultural machineries were the most relevant processes in determining the overall environmental performances of farms. Future research will be dedicated to (i) explore and better define the environmental implications of the land use impact category in the Mediterranean sheep farming systems, and (ii) contribute to revising and improving the existing LCA dataset for Mediterranean farming systems. Copyright © 2014
Full Text Available Introduction: The aim of this study was to investigate the relationship between body condition score (BCS determined on the dry-off day, calving day, and in the first month of lactation, its changes during the dry period and early lactation, and periparturient indices and fertility in high-producing dairy cows. Material and Methods: The experiment was conducted in two herds: A and B, located in Western Poland. The studies were conducted on 116 and 108 Polish Holstein-Friesian dairy cows respectively, with an average milk yield of >10 000 kg/305-day lactation. The experiment included the dry period (-56 d to the calving day, the calving day, and early lactation (from +1 to +56 d. The experimental factor was BCS (0 to 5-point scale. The BCS was performed by one person on day -56, on parturition day (in the first 12 h after calving and on day 30 of lactation. Results: A decrease in BCS (≥-0.25 in herd A during the dry period accelerated the planned calving period by 7.3 d. In the group of cows with BCS 3.50 in the first month of lactation (30 d resulted in the extension of uterine involution period (56 d. Improvement of BCS during the dry period shortened the anoestrus (60 d in herd A and the period of insemination service (60 d in herd B. However, in this group (IM BCS ≥ 0.25 of cows the day of the highest artificial insemination index (2.50 in herd B was analysed. Conclusion: The body condition on the dry-off day and at calving, as well as its deterioration in the first month of lactation, have a considerable effect on fertility indices in dairy cows, thus confirming the advisability of its regular monitoring during routine operations connected with the management of a dairy cattle herd.
Denis-Robichaud, J; Cerri, R L A; Jones-Bitton, A; LeBlanc, S J
The objectives of this study were to (1) quantify current reproduction management practices, and (2) assess the association between these practices and herd reproductive performance on dairy farms in Canada. A bilingual survey was developed, validated, and administered from March to May 2014 to collect general and reproduction management and performance measures [annual 21-d pregnancy rate (PR), 21-d insemination rate (IR), and conception risk (CR)]. Associations between management practices and reproductive performance measures were tested using linear regression models. A total of 832 questionnaires were completed online and by mail, representing a response rate of 9%. On average, farms had 77 lactating cows (median=50) and 13 dry cows (median=10), and Holstein was the most common breed (92% of herds). Lactating cow housing was tiestall on 61% of the farms, freestall on 37%, and bedded pack on 2%. The average voluntary waiting period was 58 d in milk (DIM). The main reproduction management practice per farm was defined as the means employed for >50% of inseminations. Farms reported their main reproduction management practice for first and subsequent inseminations, respectively, as visual estrus detection (51 and 44% of herds), timed AI (21 and 23% of herds), automated activity monitoring (AAM; 10 and 10% of herds), other management practice (bulls; 2 and 2% of herds), and a combination of management practices (16 and 21% of herds). On farms using visual estrus detection, cows were observed for signs of estrus on average 3.5 times per day, for an average total of 36 min/d. The most common use of reproductive hormones was to synchronize ovulation using Ovsynch (58% of the farms). Average PR, IR, and CR were 17.6, 44.1, and 40.5%, respectively. In linear regression analyses adjusted for confounders, pregnancy rate was significantly associated with geographic region, housing (tiestall: PR=15.4%, freestall: PR=17.6%), herd size (100 cows: PR=17.8%), voluntary waiting
Leenhouwers, J. I.; Ten Napel, J.; Hanenberg, E. H. A. T.; Merks, J. W. M.
In this study, breeding structures and commercial sow lines were evaluated by economic and genetic simulation studies for their suitability to provide the Dutch organic pig sector with replacement gilts. Sow and litter performance from over 2000 crossbred sows from 2006 to 2007 were collected on 11 to 14 Dutch organic pig herds, respectively, and compared with conventional herds. Results showed that organic herds had lower farrowing rates (3.6% to 7.5%), more live born piglets per litter (0.4...
Andreas Diomedes Soteriades
Full Text Available Applying holistic indicators to assess dairy farm efficiency is essential for sustainable milk production. Data Envelopment Analysis (DEA has been instrumental for the calculation of such indicators. However, ‘additive’ DEA models have been rarely used in dairy research. This study presented an additive model known as slacks-based measure (SBM of efficiency and its advantages over DEA models used in most past dairy studies. First, SBM incorporates undesirable outputs as actual outputs of the production process. Second, it identifies the main production factors causing inefficiency. Third, these factors can be ‘priced’ to estimate the cost of inefficiency. The value of SBM for efficiency analyses was demonstrated with a comparison of four contrasting dairy management systems in terms of technical and environmental efficiency. These systems were part of a multiple-year breeding and feeding systems experiment (two genetic lines: select vs. control; and two feeding strategies: high forage vs. low forage, where the latter involved a higher proportion of concentrated feeds where detailed data were collected to strict protocols. The select genetic herd was more technically and environmentally efficient than the control herd, regardless of feeding strategy. However, the efficiency performance of the select herd was more volatile from year to year than that of the control herd. Overall, technical and environmental efficiency were strongly and positively correlated, suggesting that when technically efficient, the four systems were also efficient in terms of undesirable output reduction. Detailed data such as those used in this study are increasingly becoming available for commercial herds through precision farming. Therefore, the methods presented in this study are growing in importance.
This is a review, written for a lay publication whose core audience in dairy producers. Control of BVD in any dairy operation must rely on the implementation of an organized strategy combining biosecurity, surveillance and increased herd resistance. This article discusses the design and implementati...
Krupová, Z; Wolfová, M; Krupa, E; Oravcová, M; Daňo, J; Huba, J; Polák, P
The objective of this study was to carry out a sensitivity analysis on the impact of various production strategies and performance levels on the relative economic values (REVs) of traits in dairy sheep. A bio-economic model implemented in the program package ECOWEIGHT was used to simulate the profit function for a semi-extensive production system with the Slovak multi-purpose breed Improved Valachian and to calculate the REV of 14 production and functional traits. The following production strategies were analysed: differing proportions of milk processed to cheese, customary weaning and early weaning of lambs with immediate sale or sale after artificial rearing, seasonal lambing in winter and aseasonal lambing in autumn. Results of the sensitivity analysis are presented in detail for the four economically most important traits: 150 days milk yield, conception rate of ewes, litter size and ewe productive lifetime. Impacts of the differences in the mean value of each of these four traits on REVs of all other traits were also examined. Simulated changes in the production circumstances had a higher impact on the REV for milk yield than on REVs of the other traits investigated. The proportion of milk processed to cheese, weaning management strategy for lambs and level of milk yield were the main factors influencing the REV of milk yield. The REVs for conception rate of ewes were highly sensitive to the current mean level of the trait. The REV of ewe productive lifetime was most sensitive to variation in ewe conception rate, and the REV of litter size was most affected by weaning strategy for lambs. On the basis of the results of sensitivity analyses, it is recommended that economic values of traits for the overall breeding objective for dairy sheep be calculated as the weighted average of the economic values obtained for the most common production strategies of Slovak dairy sheep farms and that economic values be adjusted after substantial changes in performance levels
Raylon Pereira Maciel
Full Text Available ABSTRACT The objective of the study was to assess the effects of including 0, 79.8, 159.8, and 240.0 g kg-1 crude glycerin in the total diet dry matter on the 84 days feedlot performance, nutrient digestibility, blood parameters, and carcass characteristics of crossbred dairy steers. Experimental diets were composed of 98.5 g kg-1 of sorghum silage and 901.5 g kg-1 of concentrate. Twenty-four crossbred dairy steers (337.3±39.8 kg body weight and 15 months of age were distributed in a completely randomized design with four treatments and six replicates. The intake and digestibility of the dry matter and nutrients were not altered by including crude glycerin in the diet. Crude glycerol levels did not affect the final weight (430.2 kg, daily weight gain (1.38 kg day-1, total weight gain (97.2 kg, hot carcass weight (218.9 kg, cold carcass weight (215.2 kg, hot carcass yield (0.50 kg 100 kg-1 BW, longissimus dorsi area (62.86 cm², subcutaneous fat thickness (4.05 mm, and carcass physical composition. Concentrations of serum glucose, triglycerides, total cholesterol, high-density lipoprotein cholesterol, and creatinine were not altered by including crude glycerin in the diet. Crude glycerin can be added to high concentrate diet up to 240 g kg-1 without changing the animal performance, apparent digestibility of nutrients, the main carcass characteristics, and blood parameters of finishing crossbred dairy steers.
Kang'ara, J.N.N.; Kariuki, I.W.; KIruiro, E.M.; Ngugi, F.K.; Mwangi, J.N.
Studies at PRC-Embu in 1996, indicated Kenaf to be a fast growing crop under low moisture condition. As a forage, it yielded between 2300-11300 kg ha -1 DM in AEZ LM3 and LM4, respectively. It could thus, supplement the Napier grass as a fodder for dairy cattle in the marginal and low potential areas which have perennial shortage of quality forage for dairy cattle. Trials were thus conducted to evaluate the effect supplementing Kenaf silage to Napier grass on growth and milk production of dairy cattle. First atrial using dairy calves was set to determine the effect of Kenaf silage fed at three different levels namely 0%, 50% and 100%. A second was also set using lactating dairy cattle fed with Napier at three levels of Kenaf silage viz. 50%, 25% and 0%. Results indicated that, the dry matter intake of Kenaf silage alone (3.28 kg day -1 ) was lower than a combination of Kenaf silage and Napier (3.93 kg day -1 ) and that of Napier alone (4.08 kg day -1 ). also a combination of 50:50 Napier and Kenaf silage gave a better animal performance than either Napier or Kenaf silage alone. It was concluded that, Kenaf silage is a good supplement for Napier in Marginal and low potential dairy zones of Kenaf silage
Full Text Available Complying with the carrying capacity of local and global ecosystems is a prerequisite to ensure environmental sustainability. Based on the example of Swiss mountain dairy farms, the goal of our research was firstly to investigate the relationship between farm global and local environmental performance. Secondly, we aimed to analyse the relationship between farm environmental and economic performance. The analysis relied on a sample of 56 Swiss alpine dairy farms. For each farm, the cradle-to-farm-gate life cycle assessment was calculated, and the quantified environmental impacts were decomposed into their on- and off-farm parts. We measured global environmental performance as the digestible energy produced by the farm per unit of global environmental impact generated from cradle-to-farm-gate. We assessed local environmental performance by dividing farm-usable agricultural area by on-farm environmental impact generation. Farm economic performance was measured by work income per family work unit, return on equity and output/input ratio. Spearman’s correlation analysis revealed no significant relationship, trade-offs or synergies between global and local environmental performance indicators. Interestingly, trade-offs were observed far more frequently than synergies. Furthermore, we found synergies between global environmental and economic performance and mostly no significant relationship between local environmental and economic performance. The observed trade-offs between global and local environmental performance mean that, for several environmental issues, any improvement in global environmental performance will result in deterioration of local environmental performance and vice versa. This finding calls for systematic consideration of both dimensions when carrying out farm environmental performance assessments.
Garcia-Rodriguez, A.; Arranz, J.; Mandaluniz, N.; Beltrán-de-Heredia, I.; Ruiz, R.; Goiri, I.
The objective of this study was to evaluate the effects of chitosan (CHI) supplementation on production performance and blood parameters in dairy ewes. Twenty-four multiparous Latxa dairy ewes at d 16 of lactation were divided into two groups of 12 ewes each. Ewes were fed one of two experimental concentrates (0.840 kg dry matter/d), control or supplemented with 1.2% CHI, on a dry matter basis. Ewes also had free access to tall fescue hay, water, and mineral salts. The experimental period lasted for 25 d, of which the first 14 d were for treatment adaptation and the last 11 d for measurements and samplings. Supplementation with CHI decreased total (p=0.043) and fescue (p=0.035) dry matter intake (DMI), but did not affect concentrate DMI. Supplementation with CHI, moreover, increased plasma glucose (p=0.013) and BUN concentrations (p=0.035), but did not affect those of non-esterified fatty acids. Dietary supplementation with CHI, however, did not affect milk yield, 6.5% FCM, milk composition, or BW, but it improved dietary apparent efficiency by increasing the milk yield-to-DMI (p=0.055) and 6.5% FCM-to-DMI (p=0.045) ratios. In conclusion, dietary supplementation of chitosan maintained ewe performance while reducing feed intake and improving dietary apparent efficiency. (Author)
Kjær, Anne Mette; Mwebaze, Tom
elites who wanted to build a support base in their home area. In addition, the elites had special interest in dairy farming, since key elite members owned dairy cattle themselves hence have played key role in promoting the dairy sector. Liberalisation enhanced the competitiveness of the dairy sector......) established to promote efficiency in marketing of milk. With the existence of DDA, to a considerable extent there has been an improved organization of dairy farmers and traders and also the quality and safety of milk enhanced amidst conflicts....
Kim, Tae Hyong; Johnstone, Jennie; Loeb, Mark
Vaccination ideally protects susceptible populations at high risk for complications of the infection. However, vaccines for these subgroups do not always provide sufficient effectiveness. The herd effect or herd immunity is an attractive way to extend vaccine benefits beyond the directly targeted population. It refers to the indirect protection of unvaccinated persons, whereby an increase in the prevalence of immunity by the vaccine prevents circulation of infectious agents in susceptible populations. The herd effect has had a major impact in the eradication of smallpox, has reduced transmission of pertussis, and protects against influenza and pneumococcal disease. A high uptake of vaccines is generally needed for success. In this paper we aim to provide an update review on the herd effect, focusing on the clinical benefit, by reviewing data for specific vaccines.
Kim, Tae Hyong; Johnstone, Jennie; Loeb, Mark
Vaccination ideally protects susceptible populations at high risk for complications of the infection. However, vaccines for these subgroups do not always provide sufficient effectiveness. The herd effect or herd immunity is an attractive way to extend vaccine benefits beyond the directly targeted population. It refers to the indirect protection of unvaccinated persons, whereby an increase in the prevalence of immunity by the vaccine prevents circulation of infectious agents in susceptible pop...
Full Text Available Objective The objective of this study was to examine the effects of alfalfa flavonoids on the production performance, immunity, and ruminal fermentation of dairy cows. Methods The experiments employed four primiparous Holstein cows fitted with ruminal cannulas, and used a 4×4 Latin square design. Cattle were fed total mixed ration supplemented with 0 (control group, Con, 20, 60, or 100 mg of alfalfa flavonoids extract (AFE per kg of dairy cow body weight (BW. Results The feed intake of the group receiving 60 mg/kg BW of AFE were significantly higher (p<0.05 than that of the group receiving 100 mg/kg BW. Milk yields and the fat, protein and lactose of milk were unaffected by AFE, while the total solids content of milk reduced (p = 0.05 linearly as AFE supplementation was increased. The somatic cell count of milk in group receiving 60 mg/kg BW of AFE was significantly lower (p<0.05 than that of the control group. Apparent total-tract digestibility of neutral detergent fiber and crude protein showed a tendency to increase (0.05
Huuskonen, A; Tuomisto, L; Kauppinen, R
Very limited information is available on the effects of drinking water temperature on dairy calves. Therefore, the present experiment was designed to study the effects on performance, health, and water consumption of dairy calves offered drinking water either warm (16 to 18 °C) or cold (6 to 8 °C). The calves (60 calves/treatment) were housed in an insulated barn in pens (3.0 × 3.5m; 5 calves in each) providing 2.1m(2)/calf. During the experimental period (20 to 195 d of age), the calves had free access to water from an open water bowl (depth 80 mm, diameter 220 mm, 2-L capacity, 1 bowl/pen). During the preweaning period (20 to 75 d of age), all calves received milk replacer (7.5L/calf daily) and had free access to commercial starter, grass silage, and hay. During the postweaning period (75 to 195 d), the weaned calves had free access to grass silage and hay and were given 3 kg/d (air-dry basis) of a commercial concentrate mixture. During the preweaning period, the water intake of the calves offered warm water was 47% higher than that of the calves offered cold water. Water intake in both treatments increased rapidly during weaning and for a few days following weaning. At 180 to 195 d of age, the calves consumed approximately 18 to 20 L of water daily. Calves offered warm water drank 7 and 8% more water during the postweaning period and overall during the experimental period, respectively, compared with those offered cold water. No treatment differences were observed in dry matter or energy intakes, body weight gains, or feed conversion rates. Furthermore, total serum IgG concentrations of the calves did not differ during the preweaning or postweaning periods. Dairy calves consumed more warm than cold water, but the increase in water intake did not influence feed intake, body weight gain, or health parameters. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Lyimo, H L N; Laswai, G H; Mtenga, L A
and was formulated using locally available feed resources. Twenty-seven (27) male calves, with birth weight 32 ± 1.5 kg were randomly allocated to three treatments, whereby Treatment 1 (DC) calves were fed the developed concentrate, Treatment 2 (FC) calves were fed a common home made dairy cow concentrate (CP 130 g......An on-farm study was carried out in Tanzania to assess the performance of crossbred (Frisian/Ayrshire x Tanzania Shorthorn Zebu) dairy calves fed on a concentrate, previously developed and tested on-station. The developed concentrate contained 189 g crude protein (CP) and 13 ME MJ per kg DM...... and ME 13 MJ per kg DM) used by farmers in the study area. Treatment 3 (FP) was a control, where farmers followed their normal calf rearing practice with no interference. Restricted suckling, ad libitum feeding of forages and up to 1 kg concentrate were used for the calves on DC and FC. Weaning was at 12...
Luciano Soares de Lima
Full Text Available The effects of inactive dry yeast (Saccharomyces cerevisiae from sugar cane were studied in 18 primiparus Saanen dairy goats (51.07±1.43 on dry matter intake and digestibility, milk production and quality. Animals were distributed in a completely randomized design during 90 days (from day 60 of milking. Diets were composed of soybean meal; soybean meal + dry yeast; or dry yeast, as protein sources, and ground corn, mineral supplement and corn silage (40%. Animals fed the dry yeast diet showed lower intake of dry matter (DM, organic matter (OM, crude protein, ether extract and neutral detergent fiber. Diets did not influence milk yield; however the milk production efficiency (kg of milk produced/kg of crude protein ingested was better in goats fed the dry yeast diet. Acidity, somatic cell counts and milk urea nitrogen values were not affected by treatments. Animals fed the soybean + dry yeast diet had higher fat and total solids than those fed the dry yeast diet. The digestibility of DM, OM and total carbohydrate was lower for soybean only and soybean + dry yeast diets. Total digestible nutrients were higher for dry yeast and soy bean diets than soybean + dry yeast diet. Dry yeast from sugar cane is a good alternative protein source for feeding lactating dairy goats and can be recommended because it maintains the production performance.
Full Text Available The aim of this study was to determine the effect of selected bean cultivars with different levels of anti-nutritional substances on performance and metabolism of dairy cows. In the current twelve-week-long study, 32 dairy cows at 3 to 6 weeks after parturition were divided into four groups. Diets were balanced to have an analogical content of crude protein and energy. Experimental groups (MI, ME, MET were mixed to the milking concentrate consisting of 20% bean seeds (MI - MISTRAL cultivar with a low content of anti-nutritional substances; ME - MERKUR cultivar with high content of anti-nutritional substances; MET - MERKUR cultivar with technologically reduced the amount of anti-nutritional substances. Clinical evaluation of dairy cows’ health and feed intake showed no negative effect of the bean supplementations. Energy, nitrogen and mineral metabolisms were not impaired either. No significant differences were found between groups in milk performance (daily milk yield, protein and lactose production during the study. On the basis of these results, the bean can be used in 20% in the milking concentrate of dairy cattle. Health risks associated with anti-nutritional content of the native bean are not significant for high-producing dairy cattle.
Reproductive performance of dairy cows resynchronized after pregnancy diagnosis at 31 (±3 days) after artificial insemination (AI) compared with resynchronization at 31 (±3 days) after AI with pregnancy diagnosis at 38 (±3 days) after AI
Pereira, R. V.; Caixeta, L. S.; Giordano, J. O.; Guard, C. L.; Bicalho, R. C.
, metritis, or retained placenta was associated with a reduced hazard of pregnancy at P2. An economic analysis was performed by simulating a 1,000-cow commercial dairy herd using a decision support tool to estimate the net present value (NPV; $/ cow per yr) from using the 2 different pregnancy diagnosis methods. The analysis revealed minor differences in NPV between the programs, depending on the cost to perform ULTRA or PALP. In summary, we observed no difference in the reproductive performance and only a minor and fluctuating economic difference when using either PALP or ULTRA for pregnancy diagnosis of dairy cows. PMID:24094532
Full Text Available The aim of this study was to analyse the effect of supplementary feeding of DHA (Docosahexaenoic Acid rich algae product (Algae STM Alltech Inc. on production of milk, fat and protein as well as on reproduction of high yielding Holstein dairy herd. Field trial was set up on Top 10 dairy farm in western part of Slovakia, under commercial conditions. The data of high yielding dairy cows, separated in two groups of 30 (control and 29 (trial animals, were recorded for period of 3 subsequent months from October to December 2015. Animals were fed once a day Total Mixed Ration based diet with different feed mixture composition in trial group (+100 g Algae STM Alltech Inc. per cow and day. Performance data were collected in accordance with official milk recording system of Breeding Services of Slovak Republic s. e. and milk samples were collected once per month according to the A4 standard methodology. The control group showed higher level of milk production compared to trial. Our study indicated that the feeding of algae caused milk fat depression and generally lower protein content in milk. Significant impact of algae feeding was found also for the level of urea in milk. In addition, the supplementary feeding of DHA may represent effective strategy to increase the percentage of pregnancies per inseminations in lactating dairy cows.
Lima, F S; Bisinotto, R S; Ribeiro, E S; Ayres, H; Greco, L F; Galvão, K N; Risco, C A; Thatcher, W W; Santos, J E P
The objectives were to determine the effects of one or three timed artificial insemination (AI) before natural service (NS) in lactating dairy cows not observed for detection of estrus on hazard of pregnancy, days nonpregnant, and 21-days cycle pregnancy rate. A total of 1050 lactating Holstein cows were subjected to a double Ovsynch program for their first postpartum AI. On the day of first AI (78 ± 3 days in milk), cows were blocked by parity and randomly assigned to receive either one timed AI (1TAI, n = 533) or three timed AI (3TAI, n = 517) before being exposed to NS. Cows assigned to 1TAI were exposed to bulls 7 days after the first AI. Nonpregnant cows in 3TAI were resynchronized with the Ovsynch protocol supplemented with progesterone twice, with intervals between AI of 42 days, before being exposed to NS 7 days after the third AI. Cows were evaluated for pregnancy 32 days after each timed AI, or every 28 days after being exposed to NS. Pregnant cows were re-examined for pregnancy 28 days later (i.e., 60-day gestation). Exposure to heat stress was categorized based on the first AI being performed during the hot or cool season, according to the temperature-humidity index. Body condition was scored at first AI. All cows were allowed a period of 231 days of breeding, after which nonpregnant cows were censored. Pregnancy to the first AI did not differ between 1TAI and 3TAI on Day 60 after insemination (30.8 vs. 33.5%). Cows receiving 3TAI had a 15% greater hazard of pregnancy and a 17% greater 21-days cycle pregnancy rate than 1TAI and these benefits originated from the first 84 days of breeding. These changes in rate of pregnancy reduced the median and mean days nonpregnant by 9 and 10 d, respectively. Despite the long inter-AI interval in cows subjected to 3TAI, reproductive performance was improved compared with a single timed AI and subsequent exposure to NS. In dairy herds that use a combination of AI and NS, allowing cows additional opportunities to AI
Christensen, Jette; Gardner, Ian A.
Correct classification of the true status of herds is an important component of epidemiologic studies and animal disease-control programs. We review theoretical aspects of herd-level testing through consideration of test performance (herd-level sensitivity, specificity and predictive values......), the factors affecting these estimates, and available software for calculations. We present new aspects and considerations concerning the effect of precision and bias in estimation of individual-test performance on herd-test performance and suggest methods (pooled testing, targeted sampling of subpopulations...... with higher prevalence, and use of combinations of tests) to improve herd-level sensitivity when the expected within-herd prevalence is low....
Colazo, Marcos G; Mapletoft, Reuben J
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.
Data from 69,145 Holstein cows that calved for the first time in 2005 were evaluated to determine the influence of age at first calving (AFC) on first lactation and lifetime production in commercial dairy herds. A DHI database was divided into four herd management criteria (HMC). The four HMC were: ...
Full Text Available The aim of the study was to analyse the effect of feeding of different sources of NPN on nutrient utilization and production performance of dairy cows under field conditions. Balancing diets for crude protein without consideration of protein quality or rumen degradability often led to overfeeding of nitrogen and less than optimum production. High yielding dairy cows separated in two groups with 85 resp. 80 cows in each were set up for the trial. Groups were consistent according the stage of production and reproduction cycle as well as age structure. Both groups were fed concentrate mixture with the same composition with only difference in NPN/ microbial protein source, with same dosage of 100 g per cow and day. Field trial was performed for period of 3 subsequent months. Performance data were collected in accordance with official milk recording. In both groups majority of cows were on first lactation. Significant differences in daily milk production were observed 2.87 kg (P<0.01 for group 2, in fat content 0.07 % for group 2 non-significant, whereas in protein content 0.18% for group 1 significant (P<0.01 in case of first lactations. If considering first tree lactations, group 2 produced 1.7 kg milk per day more (P<0.08, with 0.05% fat more and 0.002 % protein less than group 1. The space created in dry matter intake by a concentrated slow-release NPN can be filled with high quality forage that could reduce the cost of feeding while maintaining levels of production.
Duncan, A J; Teufel, N; Mekonnen, K; Singh, V K; Bitew, A; Gebremedhin, B
Smallholder dairy production represents a promising income generating activity for poor farmers in the developing world. Because of the perishable nature of milk, marketing arrangements for collection, distribution and sale are important for enhanced livelihoods in the smallholder dairy sector. In this study we examined the relationship between market quality and basic feeding and breeding practices at farm level. We define market quality as the attractiveness and reliability of procurement channels and associated input supply arrangements. We took as our study countries, India with its well-developed smallholder dairy sector, and Ethiopia where the smallholder dairy industry has remained relatively undeveloped despite decades of development effort. We conducted village surveys among producer groups in 90 villages across three States in India and two Regions in Ethiopia. Producer groups were stratified according to three levels of market quality - high, medium and low. Data showed that diet composition was relatively similar in India and Ethiopia with crop residues forming the major share of the diet. Concentrate feeding tended to be more prominent in high market quality sites. Herd composition changed with market quality with more dairy (exotic) cross-bred animals in high market quality sites in both India and Ethiopia. Cross-bred animals were generally more prominent in India than Ethiopia. Herd performance within breed did not change a great deal along the market quality gradient. Parameters such as calving interval and milk yield were relatively insensitive to market quality. Insemination of cross-bred cows was predominantly by artificial insemination (AI) in India and accounted for around half of cross-bred cow inseminations in Ethiopia. Data on perceptions of change over the last decade indicated that per herd and per cow productivity are both increasing in high market quality sites with a more mixed picture in medium and low-quality sites. Similarly dairy
Jørgensen, Carina; Spörndly, R; Bertilsson, J
to be determined by several factors including duration of the treatment and post-treatment feeding level. The most important factor though appears to be the magnitude of over- or underfeeding (i.e., a strong relationship between the treatment period feeding level and the subsequent response in production).......In comparison with the intensive research on the direct effects of energy supply on dairy cow lactation performance, little attention has been paid to the effect of early lactation feeding on subsequent production. The present paper reviews 9 studies carried out with the aim of quantifying...... the immediate and subsequent responses in milk production and body weight to early lactation feeding. Most results showed that a more generous feeding in early lactation caused a positive carryover effect on subsequent production, whereas an inadequate level of feed in early lactation has been shown to reduce...
The term "herd immunity" for the indirect effect of meningococcal conjugate vaccines is inaccurate. A more appropriate term is "herd protection," because this term correctly describes the public effects imparted by vaccination campaigns against the meningococcus.
Full Text Available The effect of barley grain processing and source of supplemental fat on performance of lactating dairy cows were studied in a replicated 4 × 4 Latin square design with 21-d periods and a 2 × 2 factorial arrangement. Eight Holstein cows with mean body weight (BW of 572 ± 71 kg and 45 ± 10 days in milk were allocated to 4 dietary treatments including 1 ground barley with cottonseed 2 pelleted barley with cottonseed 3 ground barley with canola seed 4 pelleted barley with canola seed. The nitrogen intake and fecal N were higher in cows fed ground barley in comparison with those fed pelleted barley. Source of supplemental fat or barley processing had no effect on milk fat and milk protein contents. Milk SNF yield was higher in cows fed canola as supplemental fat source and ground barley (P < 0.05. Milk yield was affected by method of barley grain processing and was 0.64 to 1.9 kg/d higher in cows fed ground barley compared with those fed pelleted barley (P = 0.04. Plasma concentrations of glucose, NEFA, BHBA, cholesterol, triglycerides and blood urea nitrogen were similar in all treatments. Dry matter intake was affected by barley grain processing. The cows fed ground barley consuming 1.15 to 2.18 kg/d more DM compared with those fed pelleted barley (P = 0.04.Total tract digestibilities of DM, crude fat, ADF, NDF and OM were not affected by the barley grain processing as well as source of oilseed. The results indicated that interactions between barley grain processing and source of supplemental dietary fat can improve the performance of lactating dairy cows, However, more detailed studies are required
Rutherford, Andrew J; Oikonomou, Georgios; Smith, Robert F
Our aims were to investigate the influence of subclinical ketosis (SCK) on physical activity at estrus using a neck accelerometer device and on future reproductive performance. Two hundred three Holstein-Friesian cows were studied on 3dairy farms in Northwest England between September 2013 and March 2014. Seventeen percent (35 of 203) of the enrolled cows were affected with SCK between 7 and 21d in milk, defined as a blood β-hydroxybutyrate concentration of 1.2 to 2.9mmol/L. Time to event analyses and multivariable regression analyses were used to assess the effect of SCK on reproductive performance and activity at estrus. The SCK cows exhibited a lower peak activity (measured as the number of standard deviations above mean activity) and shorter duration in activity clusters associated with first estrus and first insemination postpartum, compared with non-SCK cows. Peak activity and cluster duration associated with the insemination that led to a pregnancy were not different between SCK and non-SCK cows. Calving to first estrus, calving to first insemination, and calving to pregnancy intervals were prolonged in SCK cows. First insemination was 4.3 times (95% confidence interval=1.6 to 15.0) less likely to be successful in SCK cows compared with non-SCK cows. Adjusted mean number of inseminations per pregnancy was 2.8 for SCK cows and 2.0 for non-SCK cows. The current study confirms the long-lasting effects of SCK on reproductive efficiency. Furthermore, it is indicated that physical activity around estrus is reduced by SCK in early lactation, but this negative effect appears to diminish as cows progress through lactation. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Dairy goat husbandry amongst the household agriculture: herd and economic indexes from a case study in Rio de Janeiro, Brazil A caprinocultura leiteira na agricultura familiar: índices zootécnicos e econômicos de um estudo de caso no estado do Rio de Janeiro, Brasil
Ricardo Augusto Mendonça Vieira
Full Text Available Two dairy goat systems conducted according to the household model were evaluated in terms of income generation. An enterprise budget analysis was performed using data collected from August, 2004, to July, 2005. Farms named A and B were smallholdings and raised Saanem goats intensively. Herd indexes, incomes, taxes, fuel, energy, concentrates, opportunity costs and interest in capital were computed. Net present value and internal rate of return were estimated to appreciate the business appeal in terms of income generation. Herd indexes were mostly affected by management decisions interfering on the amounts and time-trends related to milk production. Seasonal variation was reduced at unit B due to heat induction, a decision not shared by farmer A. The daily body weight gain of doelings after weaning (89 and 76 g/d for A and B was low if compared to current recommendations. Average records of lactation (441 and 606 L/doe and fertility (86.95% and 85.71% were amongst the literature range. Daily tasks related to unit B consumed 5 hours and 55 minutes for an average milk production of 40.9 L/d, whereas 8 hours and 16 minutes on average were daily spent at unit A in order to produce 32.2 L/d. Unit B presented a total production cost (R$ 0.79548/L lower than unit A (R$ 1.50239/L, but operated profitably. Unit A presented a positive gross margin (R$ 0.284/L, but operated unprofitably. The income generated on B was equivalent to a monthly salary of R$ 732.96 (US$ 278.52, a competitive income compared to the Brazilian minimum wage of R$ 300.00 (US$ 114.00 paid monthly. These results corroborate the hypothesis that the dairy goat husbandry fits adequately to the household production model and generates income competitively.Dois sistemas de produção de caprinos leiteiros praticados de acordo com o modelo familiar foram avaliados quanto à geração de renda. Um teste para verificação de viabilidade econômica do empreendimento foi executado utilizando
Maria Amélia Menck Soares
Full Text Available Three different regions of the alpha s1-casein gene (CSN1S1 were investigated to determine the frequencies of major alleles for null, low, intermediate and high milk protein expression in a herd of dairy goats raised in the southeastern region of Brazil. Genomic DNA samples were obtained from leukocytes of 145 dairy goats and regions of interest in the gene were amplified through Polymerase Chain Reaction (PCR, then evaluated in both agarose (O and E allele and polyacrylamide gels (F allele. For better characterization of the F allele, a PCR-RFLP (PCR-Restriction Fragment Length Polymorphism study was performed employing the endonuclease XmnI. The allelic frequencies in the herd of 62 Saanen goats studied were: CSN1S1E = 0.35; CSN1S1F = 0.30; CSN1S1O1 = 0.02; CSN1S1A+B+C = 0.30, other alleles = 0.03. In another group of 83 Alpine animals, the frequencies were: CSN1S1E = 0.48; CSN1S1F = 0.28; CSN1S1O1 = 0.01; CSN1S1A+B+C = 0.20, other alleles = 0.03. In the region of exon 9 and intron downstream, where mutations that characterize the F allele occur, it was verified that different intragenic haplotypes may exist, involving the deletion of the 23rd nucleotide in the ninth exon in addition to the insertion of 11bp on intron. These haplotypes may be used to make direct association with other alleles. Although rare, a higher number of combinations were found in this work by evaluating in conjunction the region of the insertion of 3bp in the referred intron, which may allow a higher number of associations. A complete characterization of these combinations will allow elaborating simplified protocols to identify animals concerning the alleles of CSN1S1 gene in goats.Foram investigadas três regiões do gene da alpha s1-caseína (CSN1S1 para determinar as frequências dos principais alelos para nula, baixa, média e alta expressão desta proteína no leite em um rebanho de cabras leiteiras na Região Sudeste do Brasil. O DNA genômico foi isolado a partir
This study explored the effect of feeding different starch concentrations and conventional or brown midrib corn silage on the performance of lactating dairy cows. Forty-eight Holstein cows were assigned to 1 of 4 diets using a randomized complete block design with a 2-wk covariate period followed by...
Zijderveld, van S.M.; Fonken, B.C.J.; Dijkstra, J.; Gerrits, W.J.J.; Perdok, H.B.; Fokkink, W.B.; Newbold, J.R.
Two experiments were conducted to assess the effects of a mixture of dietary additives on enteric methane production, rumen fermentation, diet digestibility, energy balance, and animal performance in lactating dairy cows. Identical diets were fed in both experiments. The mixture of feed additives
Conclusion: The norgestomet Crestar® treatment carried out during 9–10 days did not improve reproductive performance in dairy cattle. However, these data demonstrate that this hormonal protocol can be used to obtain high oestrus cow rates to initiate correct timing of insemination.
Cui, K; Guo, X D; Tu, Y; Zhang, N F; Ma, T; Diao, Q Y
The effect of long-term dietary supplementation with rutin on the lactation performance, ruminal fermentation and metabolism of dairy cows were investigated in this study. Twenty multiparous Chinese Holstein cows were randomly divided into four groups, and each was offered a basal diet supplemented with 0, 1.5, 3.0 or 4.5 mg rutin/kg of diet. The milk yield of the cows receiving 3.0 and 4.5 mg rutin/kg was higher than that of the control group, and the milk yield was increased by 10.06% and 3.37% (p cows supplemented with 0 or 3.0 mg rutin/kg of diet were used to investigate the effect of rutin supplementation on blood metabolites and hormone levels. Compared with the control group, the serum blood urea nitrogen (BUN) concentration of the 3.0 mg rutin/kg group is significantly decreased (p cows with permanent rumen fistula and duodenal cannulae were attributed in a self-control design to investigate the peak occurrence of rutin and quercetin in different parts of the gastrointestinal tract, ruminal fermentation and microbial population in dairy cows. The cows supplemented with 3.0 mg rutin/kg in the diet differed from the control period. Samples of rumen fluid, duodenal fluid and blood were collected at 1, 2, 3, 4, 5, 6, 7 and 8 h after morning feeding. Compared to the control group, the pH, ammonia nitrogen concentration, number and protein content of rumen protozoa and blood urea nitrogen were lower, but the concentration of total volatile fatty acid (TVFA), microbial crude protein (MCP) and serum lysozyme content were higher for the cows fed the rutin diets. The addition of 3.0 mg rutin/kg to diets for a long term tended to increase the milk yield and improve the metabolism and digestibility of the dairy cows. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.
Keywords: Dairy cows, Perennial ryegrass, Rumen fill, Clearance, Degradation, Grazing behaviour.In temperate environments, perennial ryegrass is the most widely used species for feeding dairy cows. That is because of its high productivity, palatability, digestibility and nutritive
Full Text Available The present experiment aimed to evaluate the effect of HMBi on the production performance and metabolism in dairy cows. Thirty multiparous Holstein dairy cows under similar conditions were randomly assigned to three dietary treatments; i Control, a basal diet; ii T1, a basal diet plus HMBi (0 g prepartum and 18 g postpartum; and iii T2, a basal diet plus HMBi (10 g prepartum and 18 g postpartum. Treatments were initiated 21 d before expected calving and continued through 91 d postpartum. HMBi was top-dressed onto the total mixed ration of each cow. Treatments did not affect dry matter intake, plasma urea nitrogen, peak milk yield, days to peak milk yield, nonesterified fatty acid, glutamate pyruvate transaminase, glutamic oxalaetic transaminase, milk fat content, milk protein content, milk lactose content, and milk solid non-fat content. The milk composition yields were increased by the HMBi-supplemented treatment. The T1 and T2 treatments increased the yields of 4% fat-corrected milk yield, milk fat, milk protein, and milk lactose compared with the control. Although there was no difference in the milk composition of the control and T2-treated cows, the T2-treated cows exhibited higher milk fat yield (increased by 74 g/d, lower milk urea nitrogen (reduced by 3.41%, and plasma β-hydroxy butyrate than the control cows. The results indicate that HMBi supplementation to diet has beneficial effects, and that there is no difference between supplementation at prepartum and starting only at parturition.
Drong, C; Meyer, U; von Soosten, D; Frahm, J; Rehage, J; Breves, G; Dänicke, S
This work examined preventive effects of a dietary and a medical intervention measure on postpartum (p.p.) ketogenesis in dairy cows overconditioned in late pregnancy. Sixty German Holstein cows were allocated 6 weeks antepartum (a.p.) to three high body condition score (BCS) groups (BCS 3.95 ± 0.08) and one low BCS group (LC, BCS 2.77 ± 0.14). Concentrate proportion in diet a.p. was higher (60% vs. 20%) and increase in proportion p.p. from 30% up to 50% decelerated (3 vs. 2 weeks) in high BCS groups. High BCS cows received a monensin controlled-release capsule (CRC) (HC/MO), a blend of essential oils (HC/EO) or formed a control group (HC). Performance parameters and energy status were evaluated in three periods [day (d) -42 until calving, one until 14 days in milk (DIM), 15 until 56 DIM]. Feed efficiency was 65% and 53% higher in HC/MO than in LC (p cows (107 mg/kg; p cows. Prevalence of subclinical and clinical ketosis was 54% and 46%, respectively, in HC group. Monensin decreased the prevalence to 50% and 7% respectively. Ruminal fermentation pattern showed higher proportions of propionate (23.43 mol % and 17.75 mol %, respectively; p dairy cows while essential oils failed to elicit any effect. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.
Kleber Regis Santoro
Full Text Available Foram utilizados registros de controle leiteiro diário, semanal, a cada 20 dias e mensal, obtidos em ordenhas da manhã, da tarde e total do dia, no período de 1988 a 2003, para estimar a produção de leite da raça Holandesa em um rebanho localizado no agreste de Pernambuco. Os dados foram relativos a 117.196 produções no dia do controle, mensuradas em 414 lactações de 188 vacas da raça Holandesa puras de origem e de alto potencial genético de produção. Nas análises estatísticas utilizou-se o modelo autorregressivo de primeira ordem. Observou-se que as autocorrelações preditas entre controle diário, semanal, a cada 20 dias e mensal foram superestimadas, em qualquer período da lactação, principalmente entre duas produções próximas e no intervalo de um a 30 dias. Independente do intervalo de controle considerado constatou-se que as correlações de Pearson foram altas entre as produções de leite da manhã, da tarde e a total diária foram altas e significativas. Assim, dentre os intervalos de ordenha estudados qualquer um pode ser indicado para estimar a produção total de leite, e fica a critério do produtor a definição entre as produções de leite da manhã, da tarde e a total diária. Independentemente do intervalo de controle adotado, se o produtor optar pela produção total do dia deve atentar para o tempo decorrido entre duas ordenhas para compor essa produção, pois o manejo da ordenha e o número de ordenhas podem afetar a fisiologia do úbere e, consequentemente, a produção de leite.Daily, weekly, monthly, and every 20 days milk records, obtained at milking in the morning, afternoon, and days totals from 1988 to 2003 were used to estimate milk production of Holstein cows in a herd located in Agreste region on Pernambuco state. The data set had 117,196 entries, acquired from 414 lactations of 188 Holstein cows and pure source of high genetic potential for production. The statistical analysis was performed
Kolling, G J; Stivanin, S C B; Gabbi, A M; Machado, F S; Ferreira, A L; Campos, M M; Tomich, T R; Cunha, C S; Dill, S W; Pereira, L G R; Fischer, V
Plant extracts have been proposed as substitutes for chemical feed additives due to their potential as rumen fermentation modifiers and because of their antimicrobial and antioxidant activities, possibly reducing methane emissions. This study aimed to evaluate the use of oregano (OR), green tea extracts (GT), and their association as feed additives on the performance and methane emissions from dairy between 28 and 87 d of lactation. Thirty-two lactating dairy cows, blocked into 2 genetic groups: 16 Holstein cows and 16 crossbred Holstein-Gir, with 522.6 ± 58.3 kg of body weight, 57.2 ± 20.9 d in lactation, producing 27.5 ± 5.0 kg/cow of milk and with 3.1 ± 1.8 lactations were evaluated (means ± standard error of the means). Cows were allocated into 4 treatments: control (CON), without plant extracts in the diet; oregano extract (OR), with the addition of 0.056% of oregano extract in the dry matter (DM) of the diet; green tea (GT), with the addition of 0.028% of green tea extract in the DM of the diet; and mixture, with the addition of 0.056% oregano extract and 0.028% green tea extract in the DM of the diet. The forage-to-concentrate ratio was 60:40. Forage was composed of corn silage (94%) and Tifton hay (6%); concentrate was based on ground corn and soybean meal. Plant extracts were supplied as powder, which was previously added and homogenized into 1 kg of concentrate in natural matter, top-dressed onto the total mixed diet. No treatment by day interaction was observed for any of the evaluated variables, but some block by treatment interactions were significant. In Holstein cows, the mixture treatment decreased gross energy and tended to decrease the total-tract apparent digestibility coefficient for crude protein and total digestible nutrients when compared with OR. During the gas measurement period, GT and OR increased the digestible fraction of the ingested DM and decreased CH 4 expressed in grams per kilogram of digestible DMI compared with CON. The use
Morais, E C; Esmerino, E A; Monteiro, R A; Pinheiro, C M; Nunes, C A; Cruz, A G; Bolini, Helena M A
The addition of prebiotic and sweeteners in chocolate dairy desserts opens up new opportunities to develop dairy desserts that besides having a lower calorie intake still has functional properties. In this study, prebiotic low sugar dairy desserts were evaluated by 120 consumers using a 9-point hedonic scale, in relation to the attributes of appearance, aroma, flavor, texture, and overall liking. Internal preference map using parallel factor analysis (PARAFAC) and principal component analysis (PCA) was performed using the consumer data. In addition, physical (texture profile) and optical (instrumental color) analyses were also performed. Prebiotic dairy desserts containing sucrose and sucralose were equally liked by the consumers. These samples were characterized by firmness and gumminess, which can be considered drivers of liking by the consumers. Optimization of the prebiotic low sugar dessert formulation should take in account the choice of ingredients that contribute in a positive manner for these parameters. PARAFAC allowed the extraction of more relevant information in relation to PCA, demonstrating that consumer acceptance analysis can be evaluated by simultaneously considering several attributes. Multiple factor analysis reported Rv value of 0.964, suggesting excellent concordance for both methods. © 2015 Institute of Food Technologists®
Subclinical ketosis in post-partum dairy cows fed a predominantly pasture-based diet: defining cut-points for diagnosis using concentrations of beta-hydroxybutyrate in blood and determining prevalence.
Compton, C W R; Young, L; McDougall, S
associated with reproductive performance in mainly pasture-fed New Zealand dairy cattle. Controlling SCK may therefore result in improvements in herd reproductive performance. However considerable variation exists among herds in the incidence of SCK and in the timing of peak prevalence which means that herd-specific monitoring programmes are required to define herd SCK status accurately.
Imaizumi, Hugo; De Souza, Jonas; Batistel, Fernanda; Santos, Flávio Augusto Portela
Cottonseed meal (CSM) is an alternative source of protein, and previous studies have been shown that it can replace soybean meal (SBM) without decrease animal performance. However, Brazilian CSM has a different chemical composition compared with the usual CSM reported in the literature. The objective of this experiment was to evaluate the effects of replacing SBM for Brazilian CSM on performance and energy balance of mid-lactating dairy cows. Forty-two Holstein cows were used in a replicate 3 × 3 Latin square design. Increasing contents of CSM (0, 15, and 30% of dry matter (DM)) were fed in diets to replace SBM. Milk yield and feed efficiency were linearly reduced with the replacement of CSM for SBM (P = 0.001). Milk fat content tended to increase quadratically (P = 0.07) with CSM addition. Replacing SBM for CSM affected milk protein content quadratically (P = 0.05). Milk urea nitrogen and plasma urea nitrogen (PUN) tended to respond quadratically (P = 0.06 and 0.10) when CSM replaced SBM to the diets. Variation in body weight (BW) also responded quadratically as CSM replaced SBM (P = 0.05). Altogether, the findings suggest better performance when cows receive SBM diet compared with the Brazilian CSM diet.
Lobago, Fikre; Bekana, Merga; Gustafsson, Hans; Kindahl, Hans
A two-year longitudinal study was conducted to assess the reproductive and lactation performances of smallholder crossbred dairy cattle in Fitche, central Ethiopia. Twenty-four smallholder dairy farms were monitored and data on reproductive, breeding, lactation and management aspects of crossbred dairy cows (n=69) were collected and analysed. Moreover, milk samples were collected and analysed for progesterone. The overall Least-squares means for calving interval (CI), calving to conception interval (CCI) and first observed oestrus after calving were 516, 253 and 141 days, respectively. Suckling significantly prolonged these intervals. The mean first onset of luteal activity (OLA) after calving was 52 days, while 67.4% n=43) had a delayed (>55 days) return to cyclicity after calving. Suckling and parity number significantly (p < 0.05) influenced the OLA. The mean lactation length was 54.4 weeks. The overall daily mean milk yield for the first 43 weeks of lactation after calving was 11.7 L/day. The estimated daily milk yield increased slowly and reached peak (13.8 L/day) around the 11th week post partum and declined gradually and steadily. Suckling status, season of calving and parity number significantly influenced the estimated daily milk yield. In conclusion, the present study indicated that the smallholder crossbred dairy cows in the study area had prolonged intervals to first oestrus after calving, to conception and to the next calving, and thus their reproductive performance is unsatisfactory. Delayed first onset of luteal activity (postpartum anoestrus) contributed to these extended intervals. Further detailed investigation is suggested to examine the effects of other relevant factors on the reproductive and lactation performances of smallholder crossbred dairy cows for appropriate intervention.
Mutimura, Mupenzi; Ebong, Cyprian; Rao, Idupulapati Madhusudana; Nsahlai, Ignatius Verla
Rearing heifers for dairy cow replacement is a challenge in smallholder dairy farms in the tropics due to feed shortage. The objective of this study was to evaluate Brachiaria hybrid cultivar Mulato II as a forage resource for improving growth performance of dairy heifers under cut-and-carry feeding system in Rwanda. Sixteen crossbred (Ankole × Jersey) heifers (mean weight 203 ± 35 kg) were randomly allocated to two dietary treatments viz: Mulato II with 2 kg/day of commercial concentrates (MCC) and Napier grass (Pennisetum purpureum) with the same supplement (NCC), for a period of 12 weeks. Mineral lick and water were provided ad libitum. Daily feed intake and fortnightly live weight were measured. Average daily gains and feed conversion ratio (FCR) were calculated. Results showed that absolute daily dry matter intake (g DMI/day) and relative intake (g/kg of metabolic body weight--BW(0.75)) were higher in heifers fed on MCC than in heifers fed on NCC (P weight (FBW) and body weight gain (BWG) did not differ between the two groups of heifers (P > 0.05). Average daily weight gain (ADWG) also not differed significantly (P > 0.05). Based on numerical body weight changes and nutritive values, Mulato II showed potential to be integrated into local cut-and-carry feeding systems for better heifer rearing to facilitate dairy cow replacement.
Langley, David J.; Tan, Chee-Wee; Worm, Daniël
The online environment offers a fertile breeding ground for anti-brand herds of disgruntled consumers. Firms are often caught off guard by the unpredictability of such herds and, as a consequence, are forced into a reactive, defensive stance. We conduct a social media analysis that aims to shed...... light on the formation, growth, and dissolution of online anti-brand herds. First we expand on the concept of environmental turbulence to advance core properties unique to online herd behavior. Next, based on evidence gathered from 40 online anti-brand herd episodes targeting two prominent firms from...... the Netherlands, we develop an analytical model to investigate drivers of herd formation, growth, and dissolution. Finally, combining environmental turbulence literature with our empirical findings, we derive a novel typology of online anti-brand herd behaviors, and put forward six propositions to guide theory...
Erich, Sarah; Kuschel, Beatrice; Schwarz, Thilo; Ewert, Jacob; Böhmer, Nico; Niehaus, Frank; Eck, Jürgen; Lutz-Wahl, Sabine; Stressler, Timo; Fischer, Lutz
The industrially utilised β-galactosidases from Kluyveromyces spp. and Aspergillus spp. feature undesirable kinetic properties in praxis, such as an unsatisfactory lactose affinity (KM) and product inhibition (KI) by galactose. In this study, a metagenome library of about 1.3 million clones was investigated with a three-step activity-based screening strategy in order to find new β-galactosidases with more favourable kinetic properties. Six novel metagenome β-galactosidases (M1-M6) were found with an improved lactose hydrolysis performance in original milk when directly compared to the commercial β-galactosidase from Kluyveromyces lactis (GODO-YNL2). The best metagenome candidate, called "M1", was recombinantly produced in Escherichia coli BL21(DE3) in a bioreactor (volume 35 L), resulting in a total β-galactosidase M1 activity of about 1100 μkatoNPGal,37 °C L(-1). Since milk is a sensitive and complex medium, it has to be processed at 5-10 °C in the dairy industry. Therefore, the β-galactosidase M1 was tested at 8 °C in milk and possessed a good stability (t1/2=21.8 d), a desirably low apparent KM,lactose,8 °C value of 3.8±0.7 mM and a high apparent KI,galactose,8 °C value of 196.6±55.5 mM. A lactose hydrolysis process (milk, 40 nkatlactose mLmilk,8 °C(-1)) was conducted at a scale of 0.5L to compare the performance of M1 with the commercial β-galactosidase from K. lactis (GODO-YNL2). Lactose was completely (>99.99%) hydrolysed by M1 and to 99.6% (w/v) by K. lactis β-galactosidase after 25 h process time. Thus, M1 was able to achieve the limit of lactose per litre milk, which is recommended for dairy products labelled as "lactose-free". Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.
Dechow, C D; Rogers, G W
Expectation of genetic merit in commercial dairy herds is routinely estimated using a 4-path genetic selection model that was derived for a closed population, but commercial herds using artificial insemination sires are not closed. The 4-path model also predicts a higher rate of genetic progress in elite herds that provide artificial insemination sires than in commercial herds that use such sires, which counters other theoretical assumptions and observations of realized genetic responses. The aim of this work is to clarify whether genetic merit in commercial herds is more accurately reflected under the assumptions of the 4-path genetic response formula or by a genetic lag formula. We demonstrate by tracing the transmission of genetic merit from parents to offspring that the rate of genetic progress in commercial dairy farms is expected to be the same as that in the genetic nucleus. The lag in genetic merit between the nucleus and commercial farms is a function of sire and dam generation interval, the rate of genetic progress in elite artificial insemination herds, and genetic merit of sires and dams. To predict how strategies such as the use of young versus daughter-proven sires, culling heifers following genomic testing, or selective use of sexed semen will alter genetic merit in commercial herds, genetic merit expectations for commercial herds should be modeled using genetic lag expectations. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Mohd Nor, N; Steeneveld, W; Mourits, M C M; Hogeveen, H
Dairy farmers often keep almost all their newborn heifer calves despite the high cost of rearing. By rearing all heifer calves, farmers have more security and retain flexibility to cope with the uncertainty in the availability of replacement heifers in time. This uncertainty is due to mortality or infertility during the rearing period and the variation in culling rate of lactating cows. The objective of this study is to provide insight in the economically optimal number of heifer calves to be reared as replacements. A herd-level stochastic simulation model was developed specific for this purpose with a herd of 100 dairy cows; the biological part of the model consisted of a dairy herd unit and rearing unit for replacement heifers. The dairy herd unit included variation in the number of culled dairy cows. The rearing unit incorporated variation in the number of heifers present in the herd by including uncertainty in mortality and variation in fertility. The dairy herd unit and rearing unit were linked by the number of replacement heifers and culled dairy cows. When not enough replacement heifers were available to replace culled dairy cows, the herd size was temporarily reduced, resulting in an additional cost for the empty slots. When the herd size reached 100 dairy cows, the available replacement heifers that were not needed were sold. It was assumed that no purchase of cows and calves occurred. The optimal percentage of 2-wk-old heifer calves to be retained was defined as the percentage of heifer calves that minimized the average net costs of rearing replacement heifers. In the default scenario, the optimal retention was 73% and the total net cost of rearing was estimated at €40,939 per herd per year. This total net cost was 6.5% lower than when all heifer calves were kept. An earlier first-calving age resulted in an optimal retention of 75%, and the net costs of rearing were €581 per herd per year lower than in the default scenario. For herds with a lower or
Romero, J J; Macias, E G; Ma, Z X; Martins, R M; Staples, C R; Beauchemin, K A; Adesogan, A T
The objective of this experiment was to examine effects of adding 2 exogenous fibrolytic enzymes (EFE) to the total mixed ration (TMR) on the performance of lactating dairy cows (experiment 1) and the kinetics of ruminal degradation of the diet (experiment 2). Twelve EFE had been screened in a series of in vitro assays that identified the most potent EFE and their optimal doses for increasing the digestibility of bermudagrass. In experiment 1, 66 Holstein cows (21±5 d in milk) were grouped by previous milk production and parity (45 multiparous and 21 primiparous) and assigned randomly to 1 of the following 3 treatments: (1) control (CON, untreated), (2) Xylanase Plus [2A, 1mL/kg of TMR dry matter (DM); Dyadic International, Jupiter, FL], and (3) a 75:25 (vol/vol) mixture of Cellulase Plus and Xylanase Plus EFE (3A, 3.4mL/kg of TMR DM; Dyadic International). The EFE were sprayed twice daily onto a TMR (10% bermudagrass silage, 35% corn silage, 5% alfalfa-orchardgrass hay mixture, and 50% concentrates; DM basis) and fed for a 14-d training and covariate period and a 70-d measurement period. Experiment 2 aimed to examine the in situ DM ruminal degradability and ruminal fermentation measurements of the diets fed in experiment 1. Three ruminally fistulated lactating Holstein cows were assigned to the diets. The experiment had a 3×3 Latin square design with 23-d periods. In experiment 1, application of 2A increased intakes (kg/d) of DM (23.5 vs. 22.6), organic matter (21.9 vs. 20.9), and crude protein (3.9 vs. 3.7) and tended to increase yields (kg/d) of fat-corrected milk (41.8 vs. 40.7) and milk fat (1.48 vs. 1.44). In particular, 2A increased milk yield (kg/d) during wk 3 (41.2 vs. 39.8, tendency), 6 (41.9 vs. 40.1), and 7 (42.1 vs. 40.4), whereas 3A increased milk yield (kg/d) during wk 6 (41.5 vs. 40.1, tendency), 8 (41.8 vs. 40.0), and 9 (40.9 vs. 39.5, tendency). In experiment 2, EFE treatment did not affect ruminal DM degradation kinetics or ruminal pH, ammonia
A survey of eight integrated farms in four local government areas of Sokoto state in north-western Nigeria revealed the following about dairy production on such farms:breed of cattle kept, Sokoto Gudali, Friesian, and Sahiwal; average dairy herd size,69.4 head; husbandry system was largely semi-intensive; milking was ...
A cross-sectional study was conducted from October 2007 to April 2008 on Holstein and Holstein-Zebu cross breds lactating dairy cows in and around Mekele to determine the prevalence, major risk factors and major bacterial pathogens of bovine mastitis in the study area.