Herd Performance Research Articles

The impact of the herd health interventions in small ruminants in low input production systems in Ethiopia.

Diseases have a negative impact on production and profitability of small ruminants. A good herd health program can decrease the number of sick animals and improve herd performance. In a longitudinal study, small ruminant herd health interventions such as community-based strategic gastrointestinal (GI) parasite control, prevention and control of major respiratory diseases and capacity development activities were implemented. In four districts of Ethiopia, where the Community Based Breeding Program (CBBP) is implemented, morbidity and mortality data were collected from January 2018 to July 2021 in 1047 smallholder farms with the objective of evaluating the impact of herd health interventions. A total of 2,643 sick animals and 516 deaths of small ruminants were recorded during the study period. The disease cases were categorized into eight groups: gastrointestinal, neurological, reproductive, respiratory, skin, systemic, other diseases (eye disease, foot disease etc) and unknown diseases. Chi-square and proportions were used to analyze morbidity and mortality by district, agro-ecological zone and age of the animal. The data showed that the general trend in the occurrence of cases and morbidity rate were decreasing from 2018 to 2021 in intervention villages. Overall, the morbidity rate in young animals (7.36%) was highier than in adults (3.49%) and the mortality rate difference between young and adult animals was also statistically significant (p < 0.001). The morbidity and mortality rates varied significantly (p < 0.001) among districts and among agro-ecologies. According to the data, treating and following up of infected animals reduced the mortality rate significantly. The relative risk of death in treated animals after the case reported was 0.135. Generally, the intervention impact analysis revealed that morbidity rate was significantly decreased (p = 0.009) in intervention years (6.31% in 2018 to 3.02% in 2021) and that herd health interventions provide an added value. Generally, herd health intervention had significant impact in reducing the morbidity rates in years and treatment and follow up of sick animals due to early reporting reduced mortality rate significantly. It is recommended that the herd health management should be the core activity under small ruminant production programs.

The Azawak zebu bred at the Toukounous experimental centre in Niger: reproduction performance and estimation of genetic parameters.

The aim of this study was to estimate the genetic parameters of the reproductive performance of the Azawak zebu, bred on station during the period 1981 to 2007, in order to contribute to the implementation of an effective selection programme for improving the zootechnical performance of cattle herds. The data contained records of 2453 calvings from 650 Azawak cows, daughters of 55 bulls, all bred at the Toukounous experimental centre (Niger). Non-genetic factors were evaluated using linear mixed models and genetic parameters were estimated using REML procedures with a multi-trait animal model. The effects of year and calving rank were significant (P < 0.001) for the three reproductive traits studied. Heritability was low for age at first calving (h2 = 0.09 ± 0.03) and calf birth weight (h2 = 0.07 ± 0.03). It was moderate for calving interval (h2 = 0.30 ± 0.04) indicating the possibility of genetic improvement of this trait by selection. Repeatability estimates for calf birth weight and calving interval were 0.10 ± 0.02 and 0.42 ± 0.03 respectively. Calving interval had very strong and significant genetic correlations with age at first calving (0.84 ± 0.08) and calf birth weight (-0.40 ± 0.20). There was also a significantly favourable genetic correlation between calf weight at birth and age at first calving (-0.32 ± 0.25), implying a simultaneous improvement in all three reproductive traits through selection. An increase in heritability of calf birth weight was observed after the active phase of the program, reflecting an overly open selection scheme. These genetic parameter estimates suggest that the three reproductive traits could be used in selection index with the aim to improve the three reproductive traits of Azawak cattle.

Risk factors underlining reproductive performance in smallholder beef cattle herds of South Africa

Improving the historically low reproductive performance of beef cattle in smallholder systems is essential for its productivity and profitability. Therefore, identifying and addressing risk factors associated with low performance in this system present an opportunity for improvement. The study aimed to evaluate the effect of animal and management risk factors on pregnancy rate (PR), fetal and calf loss (FC), calving interval (CI) and days open (DO) in smallholder beef cattle farms. A multi-stage selection approach was conducted in five provinces of South Africa. Cow records (3694) collected from 40 smallholder herds over two years (2018–2019) were analysed. Data on animal and herd management factors including body condition score (BCS), cow age class, breed type, lactation status, culling old/non-productive cows, record-keeping, and breeding and calving seasons were recorded. The GLIMMIX procedure was computed to determine risk factors associated with performance indicators (PR, FC, CI and DO). Risk factors highly associated with performance were breed type, BCS, cow-age class and breeding/calving season (P ≤ 0.05). Indicators FC, DO and CI increased with decreased BCS, autumn calving seasons, and in first calvers and aged cows. Whereas, PR increased with increasing odds of BCS and breeding seasons between December-March, November-February and January-March. Optimizing reproductive performance in smallholder beef cattle herds may involve managing cow body condition, breeding with adapted genotypes and synchronizing breeding with favourable seasons. Therefore, record keeping and regular monitoring of herd nutrition, climate and breed performance may be significant in improving reproductive performance in smallholder herds.

Development of an indirect ELISA for the serologic detection of bovine viral diarrhea virus based on E2 antigen sub-genotypes 1b, 1e, and 1d.

Bovine viral diarrhea virus (BVDV) causes ongoing economic losses to cattle industries, directly through reduced herd performance or indirectly through control program costs. ELISA assays, one of the most widely used techniques due to their ease of implementation, have been a valuable tool for mass surveillance and detection of BVDV. In this study, we developed a new indirect ELISA (rE2-ELISA) for serologic detection of BVDV. The assay considers three recombinant E2 protein subtypes as antigens, allowing serologic diagnosis of BVDV-1b (high prevalence worldwide), BVDV-1d and 1e (high prevalence in southern Chile) sub-genotypes. Recombinant E2 (rE2) proteins were successfully expressed in stably transfected CHO cells. Conditions for rE2 ELISAs were established after determining appropriate concentrations of antigen, blocking agent, secondary antibody, and serum dilutions to achieve maximum discrimination between positive and negative serum samples. The developed rE2-ELISA showed a sensitivity of 92.86% and a specificity of 98.33%. Clinical testing of 180 serum samples from herds in southern Chile showed high accuracy (kappa > 0.8) compared to the commercial BVDV Total Ab kit (IDEXX), with 95.37% positive and 87.5% negative predictive value. In addition, the rE2 ELISA has shown the capability to detect anti-BVDV antibodies from naturally infected animals with sub-genotypes 1b, 1e, or undetermined. These results indicate that the developed indirect ELISA could serve as a valid, and efficient alternative for identifying BVDV-infected animals, thus contributing to the success of disease control and eradication programs.

How control and eradication of BVDV at farm level influences the occurrence of calf diseases and antimicrobial usage during the first six months of calf rearing

BackgroundBovine viral diarrhoea (BVD) is one of the major cattle diseases causing economic losses worldwide. Nowadays the disease manifests mainly as virus-induced immunosuppression and early embryonic death, impacting overall herd performance and contributing to increased antibiotic usage in calf rearing.MethodsIn our study we investigated the effect of rapid BVDV control measures on calf diseases and antimicrobial usage after weaning on a large industrial dairy farm. Persistently infected (PI) animals were identified and removed from the herd within a short period of time, and all susceptible animals were vaccinated against BVDV. Recorded herd parameters and AB usage were monitored retrospectively and compared with data collected after starting the BVD control program.Results and discussionThe programme began in January 2023 with identifying and eliminating PI animals from the farm. Twenty-one PI animals were found by using RT-qPCR testing of blood sera out of the 1571 animals tested (1.33%). Subsequent testing (January and December 2023) identified further 28 PI animals amongst the 542 calves tested shortly after birth, and all were instantly removed from the farm. In parallel with the BVDV eradication measures, AB usage dropped by more than 50% compared to previous years. Calf mortality also decreased from 7.45 to 4.38% as the control program progressed. Correspondingly, both the number of respiratory and diarrhoea cases decreased dramatically on the farm while the eradication measures were in place.ConclusionOur study clearly demonstrated the positive effects of BVDV eradication on the improvement of calf health and importantly, a reduction of AB usage, contributing to the One Health perspective of farm animal production.

Effect of automated health monitoring based on rumination, activity, and milk yield alerts versus visual observation on herd health monitoring and performance outcomes

A primary objective of this randomized trial was to compare the percentage of cows that underwent clinical examination and were diagnosed with clinical health disorders (CHD) with a health monitoring program that relied only on automated monitoring system alerts vs a program that relied only on visual observation of clinical signs of disease to select cows for clinical examination. Another objective was to compare the effects of these health monitoring programs on milk yield, the herd exit dynamics (i.e., cows sold and dead), and first service reproductive outcomes. Lactating Holstein cows (n = 1,204) enrolled in the experiment were fitted with a neck-attached sensor of an automated monitoring system (HR Tags; Merck & Co., Inc.) that generated health alerts based on rumination time and activity. Milk yield was monitored 3 times per day by automated milk meters (MM27BC, DeLaval). Cows were blocked by parity, close-up period diet, and stratified by previous lactation milk yield, and then were randomly assigned within block to different programs for monitoring health from 3 to 21 d in milk (DIM). Cows in the visual observation group (VO; n = 597) were selected for clinical examination exclusively based on visual observation of clinical signs of disease, whereas cows in the automated health monitoring group (AHM; n = 607) were selected for clinical examination based on health alerts consisting of the following: a Health Index Score < 86 arbitrary units, daily rumination < 250 min, or a reduction of > 20% in daily milk yield. Once selected for examination, the clinical exam was the same for both treatment groups. Binary data such as the occurrence of CHD, herd exit, and pregnancies per AI were analyzed with logistic regression. Daily and weekly milk yield were analyzed using ANOVA with repeated measurements. More cows underwent a clinical examination, more cows were diagnosed with at least one CHD, and more cows received treatment in the AHM than the VO treatment group. Cows in the AHM treatment had more accumulated milk than cows in the VO treatment from 2 to 21 DIM. Cows in the AHM treatment diagnosed with at least one CHD produced more milk from 3 to 18 and 20 to 21 DIM than cows diagnosed with a CHD in the VO treatment. Fewer cows left the herd up to 21 DIM for the AHM than the VO treatment. Pregnancies per AI at first service were greater for the VO than the AHM treatment at 30 d but not at 50 d after AI and no difference in pregnancy loss was detected. In conclusion, a health monitoring strategy that used automated health alerts increased the risk of undergoing clinical examination and having CHD diagnosed compared with a program that selected cows for clinical examination based exclusively on visual observation. Cows monitored with the program that relied on automated alerts also had greater milk yield in the first 21 DIM. Thus, monitoring cow health based on automated behavior and milk yield alerts might be a more effective alternative for health monitoring than exclusive use of visual observation of clinical signs of disease.

Accuracy and precision of diets fed to close-up cows on dairy farms and its association with early lactation performance

Ensuring a consistent ration is critical for maximizing lactating cow performance, but this is not known for dry cows. The objectives of this cohort observational study were to: 1) characterize close-up dry cow diets fed on commercial farms in Ontario, Canada, 2) describe the accuracy of the nutrient composition between the formulated close-up diet and the diet offered to the cows, 3) describe the precision of the close-up diets across time, and 4) explore potential associations of that accuracy and precision with blood metabolic parameters and milk yield of cows in early lactation. Forty free-stall dairy farms were visited once every 4 wk, for a total of 6 visits to each farm, from April to October 2022. At each visit, samples of the close-up diet were collected and analyzed for dry matter (DM) content and chemical composition. Close-up diet formulations were also obtained by each farm's nutritionists. During each visit, fresh cows (0 to 14 d in milk [DIM]) had blood samples taken for blood metabolites. The same cows were also monitored for milk yield up to 120 DIM. Multivariable models were used to analyze associations between variability (in relation to the formulated diet and across time) of nutrients in the close-up diet, as measured by coefficient of variation (CV), and outcomes in fresh cows. Corn silage (67.6% of farms) and straw (24.3% of farms) were the predominant primary forage sources used in the close-up dry cow diets. Soybean meal (37.8% of farms) and canola meal (18.9% of farms) were the main ingredients used as primary concentrate sources. Overall, the diets offered did not accurately represent the formulated diets. With the exception of net energy for lactation (NEL), the CVs for the other nutrients were all greater than 5%. Diet variability, both between fed and formulated diets and from visit to visit during the close-up period, was associated with metabolic markers and dairy cow production. Lower variability in non-fiber carbohydrates (NFC) between the fed and formulated diets was associated with better liver health index scores. Visit-to-visit variability in fat% and NFC% were associated with blood β-hydroxybutyrate (BHB) concentrations, while NFC% variability was associated with blood glucose levels. Serum nonesterified fatty acids (NEFA) concentrations were associated with visit-to-visit variability in DM% and CP%. These results underscore the importance of maintaining consistency between diet formulations and feeding practices over time to optimize early-lactation dairy herd performance and health, granted that these diets are correctly formulated to meet the nutritional needs of cows in the close-up period and applied with recommended feeding practices.

Development and evaluation of predictive models for pregnancy risk in UK dairy cows

One suggested approach to improve the reproductive performance of dairy herds is through the targeted management of subgroups of biologically similar animals, such as those with similar probabilities of becoming pregnant, termed pregnancy risk. We aimed to use readily available farm data to develop predictive models of pregnancy risk in dairy cows. Data from a convenience sample of 108 dairy herds in the UK were collated and each herd was randomly allocated, at a ratio of 80:20, to either training or testing data sets. Following data cleaning, there were a total of 78 herds in the training data set and 20 herds in the testing data set. Data were further split by parity into nulliparous, primiparous, and multiparous subsets. An XGBoost model was trained to predict the insemination outcome in each parity subset, with predictors from farm records of breeding, calving and milk recording. Training data comprised 74,511 inseminations in 45,909 nulliparous animals, 86,420 inseminations in 39,439 primiparous animals, and 158,294 inseminations in 32,520 multiparous animals. The final models were evaluated by predicting with the testing data, comprising 31,740 inseminations in 19,647 nulliparous animals, 38,588 inseminations in 16,215 primiparous animals, and 65,049 inseminations in 12,439 multiparous animals. Model discrimination was assessed by calculating the area under receiver operating characteristic curves (AUC); model calibration was assessed by plotting calibration curves and compared across test herds by calculating the expected calibration error (ECE) in each test herd. The models were unable to discriminate between insemination outcomes with high accuracy, with an AUC of 0.63, 0.59 and 0.62 in the nulliparous, primiparous and multiparous subsets, respectively. The models were generally well-calibrated, meaning the model-predicted pregnancy risks were similar to the observed pregnancy risks. The mean (SD) ECE in the test herds was 0.038 (0.023), 0.028 (0.012) and 0.020 (0.008) in the nulliparous, primiparous and multiparous subsets respectively. The predictive models reported here could theoretically be used to identify subgroups of animals with similar pregnancy risk to facilitate targeted reproductive management; or provide information about cows' relative pregnancy risk compared with the herd average, which may support on-farm decision-making. Further research is needed to evaluate the generalizability of these predictive models and understand the source of variation in ECE between herds; however, this study demonstrates that it is possible to accurately predict pregnancy risk in dairy cows using readily available farm data.

Mother-offspring bonding revisited: A blueprint for the future of beef cattle farming

This review summarizes the status of the art of cow-calf relationships at birth and during lactation, including the physiological mechanisms throughout suckling/nursing and weaning which can impact on productive and reproductive parameters, social behaviour across the mother-offspring pairs, and the required positive cow-calf welfare approach in beef cattle. The time spent close to the calf after birth, latency to nurse, nursing time, grooming and vocalisations can be considered fair proxies of oxytocin release and maternal care during the neonatal period. Besides, maternal contact during the first days after parturition will be crucial to guarantee the adequate establishment of mother-offspring bonding and the correct social and emotional development of young calf in beef cattle. During lactation, restricted nursing systems have been demonstrated as cost-effective management alternatives to improve reproductive herd performance. As artificial weaning of calves is considered a significant stressor in the lives of beef cattle, the use of a fence-line or the two-step weaning have been proposed, although no clear benefits in reducing cow-calf distress have been found. Modelling the perspective from a productive to a welfare approach in a beef cattle system is required. The ability of cows and calves to engage in voluntary, self-generated and goal-directed behaviour must be considered in the design of tailored management practices that maintain the trade-off between animal performance, cow-calf interactions, and positive mental state. Likewise, social interactions may be considered as part of environmental optimization to provide cow-calf pairs with opportunities for positive experiences and improve cattle welfare. The Five Domains Model is proposed to develop welfare-orientated management strategies considering aspects such as maternal deprivation, behavioural stress and socio-emotional development in beef cattle. This holistic approach of mother-offspring bonding focused on nutrition (Domain 1), physical environment (Domain 2), health (Domain 3), behavioural interactions (Domain 4) and animal’s mental state (Domain 5) will help to improve management decisions and cow-calf welfare state. Some management recommendations and opportunities for future studies to deeply enlarge the welfare perspective in the dyad are discussed.

Correlation between BMPR1B Gene Polymorphism and some Reproductive Traits in Awassi Sheep

The (BMPR-1B) gene is one of the main genes for ewe fertility. This study was conducted to check the association between BMPR-IB gene polymorphisms and some traits of Awassi. This study was made in Anbar Governorate - (Agricultural Research Department) Al-Dawar. Date of experience collected from 34 ewes at the age of 4-6 years. Next, DNA was extracted and a PCR reaction was performed to amplify blood samples taken from the ewes to confirm the presence of the BMPR1B gene. The sequence was determined using Sanger sequencing technology. The data were then analyzed and compared between sample sequences to determine SNPs, genotype frequencies, allele frequencies, and their association with reproductive and growth traits. The results showed mutations in the heteroplasmy site rs410310346 (T&gt;C) and rs592447725 (G&gt;A). The results indicated that the TC genotype at the mutation site rs410310346 (T&gt;C) was significantly superior (P≤0.05) in ewes whose rates of fertility and body length were higher compared to the CC genotype. The genotypes haven’t got an important effect on the proportion of twins, fertility rate, chest circumference, front height, ewe birth weight, and lamb weight at birth. The relationship of genotype GG and GA at the mutation site rs592447725 (G &gt; A) showed a very significant effect (P≤0.01) on the percentage fertility rate and a noteworthy result (P≤0.05) on body length, height at the front and birth weight of lambs, but there isn’t a big impact. In the percentage of twins, fertility rate, chest circumference, and birth weight of ewes. Therefore, the effect of the BMPR1B gene can be used as a genetic marker to select ewes with good genotypes to improve herd performance.

Climate Change and Photochemical Ozone Creation Potential Impact Indicators of Cow Milk: A Comparison of Different Scenarios for a Diet Assessment

An estimate of the environmental impact of dairy farms in Northern Italy producing milk for hard cheese (protected designation of origin) has been obtained through a comprehensive life cycle assessment. The estimate focused on climate change (CC) and photochemical ozone creation potential (POCP) indicators, which were evaluated according to the Intergovernmental Panel on Climate Change (IPCC) guidelines and interpreted with the aid of the feeds’ composition evaluated using near-infrared reflectance spectroscopy (Foss NIR-System 5000) as well as with a diet evaluation according to the NRC (National Research Council) or the CNCPS (Cornell Net Carbohydrate and Protein System) nutrient requirement modeling. Herds were classified into high-, mid-, and low-performing based on the daily milk yield per cow. A lower impact on indicators was observed as herd performance increased. The high-performing herds had a lower contribution from enteric fermentation (6.30 × 10−1 kgCO2-eq), and the more milk that they produced allowed for a differentiation of CC from land use and transformation (2.39 × 10−1 kgCO2-eq), compared to low-performing herds (3.66 × 10−1 kgCO2-eq). Compared to the IPCC approach, the CC and POCP indicator estimates were reduced when addressing the feed’s quality, particularly in mid- and high-performing herds. The results could be helpful in the dairy sector as they provide an insight into how diet quality affects the environmental impact of milk.

284 Relationship between sow caliper measurements with sow reproductive performance and longevity in the herd

Abstract Ideal conditioned sows are desired because they maximize herd performance, improve female well-being, and optimize financial outcomes. Sow productivity has increased, and body composition of females has changed, with sows being leaner and having less adipose tissue compared with their predecessors. Our objective was to determine the relationship between sow caliper measurements with sow reproductive performance and longevity in the herd. Data collected in four different production systems located in the US and Brazil were used, with 3,083, 356, 7,456, and 26,773 individual PIC Camborough observations represented within each of these databases. Caliper measurements were collected at due to farrow and weaned sows and were recorded in units, standardized to an ideal range of 12 to 15 units. Caliper change in lactation was determined as the caliper units at weaning minus the caliper units pre-farrowing. Response variables included proportion of born alive and stillborn piglets, lactation feed intake, as well as removal and mortality risk for all causes, or specifically for reproductive and pelvic organ prolapse (POP) causes. Data were analyzed using generalized linear mixed models, hazard ratio analysis, and survival models with the lmer, glmer, and surv functions of R. Sow served as the experimental unit. Caliper measurements at farrowing had curvilinear associations (P &amp;lt; 0.05) with percentage born alive piglets and percentage stillborn piglets. Increasing caliper units at farrowing resulted in linear reduction (P &amp;lt; 0.05) in lactation average daily feed intake and in linear increase (P &amp;lt; 0.05) in caliper losses during lactation. Sows losing 1 to 2, 3 to 4, or 5 and greater caliper units in lactation had 1.5, 1.8, and 2.4 times, respectively, greater risk (P &amp;lt; 0.05) of being removed from the herd in the next cycle compared with sows that gained 0 or more units. Reduced caliper units in due-to-farrow sows resulted in reduced probability (P &amp;lt; 0.05) of survival in the next cycle considering prolapse removal reasons. Sows with due to farrow caliper units of 12 to 15 had 1 to 1.6 times (95% Odd Ratio Confidence Interval), 9 to 11 had 1.2 to 2.1 times, and less than 9 caliper units 3.1 to 3.2 times greater risk of death or being removed from the herd due to POP compared with those with &amp;gt;15 units. Reduced caliper units in due-to-farrow sows resulted in reduced probability of survival in the next cycle considering all removal and mortality causes. Specifically, sows with less than 9 caliper units at farrowing had 2.0 times greater risk (P &amp;lt; 0.05) of removal and 4.4 times greater risk (P &amp;lt; 0.05) of mortality compared with sows with over 15 caliper units. In summary, both under and over-conditioned sows have reduced productivity. Underconditioned sows are at greater risk for mortality and for POP related removal.

Optimizing Feed Formulation Strategies for Attaining Optimal Nutritional Balance in High-Performing Dairy Goats in Intensive Farming Production Systems

Abstract Genetic factors play a pivotal role in shaping feed formulation strategies for dairy goats, influencing milk production, composition, and overall productivity through the modulation of genetic parameters and polymorphisms associated with milk protein fractions and yield. Moreover, environmental challenges, including heat stress and feed availability fluctuations, pose significant hurdles in achieving optimal nutrition and performance, necessitating precision livestock farming and the utilization of local by-products to mitigate their impact on herd health and productivity. In addition, nutritional interventions, such as supplement utilization and alternative feed incorporation, offer promising avenues for addressing specific deficiencies and enhancing overall performance, from fatty acid supplementation to herbal feed additives, while balancing rations to meet evolving nutritional needs and ensuring long-term sustainability remains paramount for optimizing herd nutrition, health, and performance in intensive dairy goat production systems. The aim of this study was to explore the multifaceted influences of genetic factors, environmental challenges, and nutritional interventions on feed formulation strategies and overall herd nutrition, health, and performance in intensive dairy goat production systems.

Comparisons of recycled manure solids and wood shavings/sawdust as bedding material—Implications for animal welfare, herd health, milk quality, and bedding costs in Swedish dairy herds

Increasing shortages and costs of common bedding materials have led dairy farmers in Sweden to consider using recycled manure solids (RMS), which are readily available and low cost, as an alternative bedding material. The main risks are effects on udder health and milk quality, but RMS could also affect animal welfare and claw health. The advantages and disadvantages of using RMS bedding have not been fully investigated, and findings in other countries cannot be directly applied to Swedish conditions and climate. This observational cross-sectional study investigated the use of RMS as bedding, regarding associations with certain aspects of animal welfare, herd health, milk quality, and bedding costs in Swedish dairy herds. Thirty-four dairy farms using RMS or wood shavings/sawdust (each n = 17) were compared. Each farm was visited 2 times during the housing period from 2020 to 2021, once from October to December and once from March to May. Dairy barns were observed, animal welfare was assessed, and freestall dimensions were measured. Farm owners were interviewed about housing system characteristics, herd performance, and herd management. Data on milk production and herd health were obtained from the Swedish official milk recording scheme for the indoor period from October to March. The prevalence of claw disorders and abnormal claw conformation were collected from the national claw health database for the period from October to May. On each farm visit, composite samples of unused bedding outside the barn and used bedding material from the freestalls, respectively, were taken for total bacterial count and DM analysis. Samples of bulk tank milk for determination of total bacterial count were taken in connection to the visits. In addition, samples of unused and used bedding material and manure from alleys for analysis of 3 Treponema species associated with digital dermatitis (DD) were gathered and analyzed. Total bacterial count was significantly higher in unused (8.50 log10 cfu/g) and used RMS bedding (9.75 log10 cfu/g) than in wood shavings/sawdust (used 4.74; unused 8.63 log10 cfu/g), but there were no significant differences in bulk milk total bacterial count (median 4.07 vs. 3.89 log10 cfu/mL) or SCC (median 243,800 vs. 229,200 cells/mL). The aspects of animal welfare assessed did not differ significantly between the 2 bedding systems, whereas the prevalence of total claw disorders (25.9% vs. 38.0% of trimmed cows), dermatitis (6.9% vs. 16.2% of trimmed cows) and sole ulcers (2.0% vs. 4.0% of trimmed cows) were significantly lower in the RMS herds. Treponema spp. were not detected in unused RMS material, but all RMS herds had presence of DD recorded at foot trimming. An economic assessment based on the interview results and price level from winter 2021 revealed that the costs of RMS bedding varied with amount of RMS produced. Thus, RMS is a potential alternative bedding material for dairy cows in Sweden and can be a profitable option for large dairy herds. However, the high level of total bacteria in the material requires attention to bedding and milking routines as well as regular monitoring of herd health.

Neospora caninum antibodies in bulk tank milk from dairy cattle herds in Italy in relation to reproductive and productive parameters and spatial analysis

Among the available diagnostic techniques, antibody detection in bulk tank milk (BTM) represents a useful tool to estimate and monitor Neospora caninum herd prevalence.To evaluate the prevalence of N. caninum and the effect of parasite infection on herd performances, BTM samples collected from 586 dairy herds located in one of the largest dairy production areas in Italy (Lombardy) were analyzed by an indirect ELISA to detect anti-N. caninum specific antibodies. Generalized linear models (GLMs) were developed. A purely spatial analysis scanning for clusters with high or low rates for N. caninum using the Bernoulli model was performed. A maximum entropy approach was used to estimate the probability of distribution of the parasite based on occurrence records together with environmental variables.Overall, 180 herds resulted positive for N. caninum antibodies on bulk tank milk (P = 30.7 %). A higher risk of seropositivity was evidenced in the provinces of Milano, Cremona, Brescia, and Bergamo (P = 32–40 %); a lower risk was evidenced in Lodi, Pavia, and Mantova (P = 13–24 %). A higher risk of seropositivity was revealed for small-medium farms (101–300 animals) (O.R.=2.8) and for older animals with more than 4 years (O.R.=4.4).Regarding the effect of N. caninum infection on herd performances, the number of inseminations for conception was higher (> 3 inseminations), and the period from calving to conception was longer (> 150 days) for positive farms (O.R.=2.0 and O.R.=2.3, respectively); besides, lower head daily milk production (<20 kg and 21–25 kg) and mature equivalent milk yield (<11,000), and somatic cell counts higher than 300,000 cells/ml were observed for N. caninum positive herds (O.R.=0.4, O.R.=0.4 and O.R.=1.9 respectively).The geographical distribution of N. caninum positive farms with the highest level of probability covers the central sector of the Po Plain where a significant cluster for high risk of parasite infection was shown by spatial scan statistic and Maximum entropy ecological niche modelling. A further significant cluster of low risk occurred in the southern. The climatic and environmental variables with the highest training gain when used in isolation resulted altitude, land use/land cover, and other variables related to temperature and precipitation.Neosporosis is widely distributed in Italian dairy herds and an impact of the parasite on herd performances could be hypothesized. Even if the role of N. caninum in alterations of reproductive and productive parameters should be further explored, veterinarians and farmers should be aware of neosporosis, and control plans should be adopted.

Relevance of Individual Data When Assessing the Gastrointestinal Nematode Infection Level, Nutritional and Productive Variables in a Tropical Farm Context: The Median Isn't the Message.

We evaluated the relationship between individual and herd GIN infection level, nutrition, production performance and anemia parameters in a tropical farm context. Fifty-four female goats were monitored to assess their body condition score (BCS, nutritional status indicator), live weight (LW) and LW gain (LWG, both used as production level indicators), FAMACHA© and hematocrit (HT, both used as anemia indicators). Goats browsed for 4 h in a tropical forest and received balanced feed and chopped grass. The eggs per gram of feces (EPG) indicated the GIN burden, with fecal samples obtained at 7:00 (AM) and 15:00 h (PM.) from each goat at six sampling points during the study. The variables and their relationship with GIN burdens were analyzed using Kruskall-Wallis, ANOVA and Friedman tests and Spearman correlations. The fecal samples obtained in the AM and PM can be equally representative of parasitic burdens (similar and highly correlated). However, the EPG of individual goats from periods of 30 days apart can be considered independent. The BCS and LWG varied between sampling times (p < 0.05), whereas EPG, LW and HT did not (p > 0.05). The GIN burden was negatively correlated with HT and BCS (-0.21, p = 0.01 for each one). The individual pattern of infection demonstrates the true impact of GINs on their hosts. Additionally, feeding and nutritional status may present important variations influencing the performance of the goats more than the impact of GINs under the farm conditions of the present study. However, GIN infection contributed to the variation in goat health and productivity in this tropical farm.

Lactation traits and reproductive performances of Sahraoui female camel in two breeding systems at Algerian Sahara.

The main objective of this study is to determine the impact of the camel livestock system on individual and herd performances of milk production, lactation curve, fats, and protein concentrations. For this purpose, 13 she-camels of Sahraoui breed from the south eastern Algeria and belonging and semi-intensive system (N = 6) and intensive system (N = 7) were studied. Recording and sampling of milk were carried out at regular intervals during a full lactation. The lactation curve was estimated using Wood's gamma function and the t-test of independent groups was carried out to compare lactation performances, lactation curve, and reproductive parameters. The overall average daily milk (DMY), fat (DFY), and protein (DPY) yield were 6.77 ± 0.82kg/day, 4.15 ± 0.91%, and 4.49 ± 0.20%, respectively. The mean of total milk yield (TMY) was 2696.39 ± 343.86kg during a mean lactation length (LL) of 398.38 ± 20.65days. The peak of milk production (6.79 ± 0.68kg) was reached at 93.9 ± 55.8days after calving. The open day (DO) and inter-calving interval (ICI) recorded in this study were 348.38 ± 30.33 and 723.38 ± 30.33days, respectively. There is no significant difference (p > 0.05) between intensive and semi-intensive breeding systems for TMY (2795.39 ± 261.88kg vs. 2580.89 ± 414.43kg), DMY (6.96 ± 0.66kg vs. 6.55 ± 1.00kg), and LL (402.14 ± 21.18days vs. 394 ± 21.03days). However, the total amount of fat was significantly higher in intensive system (182.02 ± 33.91kg) and the DPY content was significantly higher in semi-intensive system (4.60 ± 0.13%). The parameters α, β, and γ of lactation, fat, and protein curves between the two systems showed a highly significant difference (p < 0.01) for the parameters (α and β) for the milk production curve, significant (p < 0.05) for the time to reach peak yield, and no significance for the other parameters. The corresponding values of the coefficient of determination (R2) were 0.62, 0.35 for milk yield (p > 0.05), 0.12, 0.13 (p > 0.05) for fat, and 0.03, 0.11 (p < 0.05) for protein, in the intensive and semi-intensive systems, respectively. In addition, DO and ICI were not significantly different between the livestock systems, but were higher in the intensive system than the semi-intensive system (337.17 ± 26.26 vs. 712.17 ± 26.26, respectively). The study concluded that the intensive system had a higher milk performance with a more efficient lactation curve. The incomplete gamma model (Wood) used in this study was inappropriate for estimating milk yield, but acceptable for fat and protein.

Evaluation of parity and its interaction effect with season of calving, period of calving on production and reproduction traits in Hardhenu (Bos taurus × Bos indicus) dairy cattle

AbstractThis study investigated the impact of parity, period of calving, and season of calving on various production and reproduction traits in Hardhenu cattle. Third‐parity cows outperformed first and second‐parity cows, exhibiting significantly higher total milk yield (TMY), 305 days milk yield (305d MY), peak yield (PY), and artificial insemination per conception (AIPC) (p &lt; .01). The Lactation length (LL) was inversely related to parity, with first‐parity cows having extended lactations (p &lt; .05). The period of calving had a substantial influence on production traits. The season of calving was critical, affecting production traits differently across parities. First‐parity cows had the highest TMY and 305d MY during winter and summer calving, with summer calving associated with shorter LL (p &lt; .05). Second‐parity cows showed higher TMY and 305d MY during summer calving, while third‐parity cows had higher TMY in winter (p &lt; .01). PY followed similar patterns to TMY, with LL affected by the season of calving. Additionally, the study explored interactions between parity, period of calving, and season of calving on reproduction traits. Third‐parity cows had higher AIPC compared to first and second‐parity cows (p &lt; .01). Reproduction traits were also significantly affected by the period of calving, with cows calving in the 2017–2021 period displaying longer service period (SP), calving interval (CI), dry period (DP), and AIPC (p &lt; .01). These findings highlight the complex interplay of biological, environmental, and management factors in shaping the productivity and reproductive efficiency of Hardhenu cattle, emphasizing the need for multifaceted considerations to optimize herd performance.

Farmers' Perceptions on Implementing Automatic Milking Systems in Large USA Dairies: Decision-Making Process, Management Practices, Labor, and Herd Performance.

Automatic Milking System (AMS) installations are increasing in the USA despite the higher investment cost than conventional systems. Surveys on AMSs conducted outside the USA focused on small-medium herds, specific regions, or aspects of AMS milking. This study described farmers' perceptions about the decision-making process of adopting an AMS in the USA's large dairies (≥7 AMS boxes) regarding changes in technology, housing, management practices, labor, herd performance, and health. After being contacted, 27 of 55 farmers from large AMS herds completed the survey. The main reasons for adopting an AMS were labor costs, cows' welfare, and herd performance. Most farms constructed new barns, used a free-flow traffic system, and changed their feed management. Increases in water and energy use were perceived by 42% and 62% of farmers, respectively. Farmers estimated decreases in labor costs of over 21%, and AMS employees worked 40-60 h/week. Milk production increases were reported by 58%, with 32% observing higher milk fat and protein content. Easier sick cow detection, better mastitis management, and improvements in pregnancy rates were reported. Thus, farmers transitioning to AMSs perceived altered resource utilization, labor cost savings, and improvements in employee quality of life, animal welfare, and farm management. While 54% of respondents would recommend an AMS to other farms, 38% suggested considering additional aspects prior to adoption.

Fluctuations of testosterone and cortisol levels in male dromedary camels in response to behavioral and management situations.

Biostimulation is a management practice that improves the reproductive parameters, potentiates the desire, and improves the reproductive efficiency during the short breeding season in camels. This study aims to investigate the concurrent changes in hormonal profiles in response to management and behavioral situations on camel farms in the Eastern region of Saudi Arabia. A total of 10 male and 50 female camels were used in this study. The hormonal profile of male camels was evaluated weekly starting from December to August. The results show that both serum testosterone and cortisol levels increased (p < 0.01) from December to March compared to April to August. A strong negative correlation was observed between testosterone levels and temperature (r = -0.81, p < 0.05), and a similarly robust negative correlation was found between cortisol levels and temperature (r = -0.83, p < 0.05). The dominant rutting males showed higher levels of testosterone than the submissive males. Serum testosterone levels increased (p < 0.01) in males out of rutting after hearing the sounds of other couples before and during mating. Hearing sounds emitted during mating increases the testosterone output, and improves the libido of male camels during the nonrutting period. It is important to keep two individually housed males for mating purposes. One male joins the herd alone in winter (winter rutter), and the other joins in spring (spring rutter), this could keep the libido extended rutting and improve the reproductive performance in camel herds.