Large Herd Size Research Articles

Bovine tuberculosis reactor cattle in Southwest Ethiopia: Risk factors for bovine tuberculosis

Bovine tuberculosis, caused by Mycobacterium bovis, is a chronic zoonotic disease that persists in Ethiopia despite global control efforts, impacting public health and the economy. However, little is known about the epidemiology of bovine tuberculosis in Southwest Ethiopia. This study aims to assess the prevalence of bovine tuberculosis and identify associated risk factors in dairy cattle. A cross-sectional study was conducted from October 2022 to October 2023 in four districts in the Sheka, Bench-Sheko, and Keffa zones. A multistage sampling approach was employed, resulting in the selection of 1,152 cattle from various herds. Tuberculin skin testing was performed to detect bovine tuberculosis, and data on potential risk factors were collected through questionnaires. Logistic regression models were used to analyze the association between bovine tuberculosis and various risk factors. The overall prevalence of bovine tuberculosis was 4.95% at the cow level and 22.19% at the herd level in the study areas. Significant herd-level risk factors for bovine tuberculosis included lowland areas, larger herd sizes, and the introducing new animals. At the cow level, risk factors included age, breed, body condition, herd size, introduction of new animals, and management system. The study reveals a high prevalence of bovine tuberculosis in dairy cattle in Southwest Ethiopia, identifying key risk factors. Effective control requires targeted interventions, such as improved management practices, enhanced farmer awareness, and a better understanding of and guidance on bovine tuberculosis strategies in Ethiopia. Future research should isolate and characterize M. bovis in the study areas.

Strategies of positive deviants in fodder conservation among smallholder dairy farming systems in highlands and midlands of Kenya.

Fodder scarcity and low quality affect the productivity of dairy cattle in Kenya yet only few smallholder dairy farmers show positive deviance in fodder conservation. Information on the strategies of such positive deviant (PD) farmers is scanty. The objective of this study was to determine strategies that distinguish PDs from peers (non-PDs) in fodder conservation among smallholder dairy farmers in highlands and midlands of Kenya. A cross-sectional survey was conducted among farms producing and conserving fodder in Tharaka Nithi County. Multistage sampling procedures was used; purposive sampling of the Sub-counties and locations, random selection of villages and proportional selection of 246 farms through snowball chain referral. Data were collected on demographic, socio-economic, farm characteristics and fodder conservation. Farms were categorized as PDs (n = 24) or non-PDs (n = 97). The PDs conserved fodder adequate to last dry season (about 3 months) and had milk yield 15kg/cow/day and above, while non-PDs do not qualify for both criteria. Chi-square and T-test were used to analyze categorical and continuous variables respectively. Logit regression was used to examine independent variables that influence probability of PDs. Farmers with high school and tertiary education who accessed extension services were PDs while non-PDs had non-formal and primary education and access extension less. Farms conserving hay and silage dominated PDs. Land in hectare (ha) and herd sizes in Tropical Livestock Unit (TLU) distinguished PDs (1.7ha and 9.0 TLU) from non-PDs (0.7ha and 3.3 TLU). The strategies that distinguished PDs from non-PDs were allocating land to fodder production, high milk yield kg/cow/day, large herd size and access to extension services. Increasing access to extension and resources (land) raised chances of PDs in fodder conservation. Knowledge of PDs strategies is important for fodder conservation, improve productivity and inform direction of future research.

Herd–level risk factors associated with preweaning mortality on Ontario dairy farms

The objective of this cross-sectional, herd-level study was to identify associations between calf management practices and herd-level preweaning mortality on Ontario dairy farms. From April to August 2022, a convenience sample of 100 dairy farms from Ontario, Canada, were visited once. A questionnaire, covering farm biosecurity, calving, colostrum management, preweaning nutrition, and housing, was verbally administered at each farm visit. Furthermore, data regarding preweaning calf mortality were retrieved from each farm's herd management software or records, including the total count of calves that survived, were culled, or died during the preweaning period for the 365 d before the farm visit. Preweaning mortality was defined as the proportion of calves that died between ≥48 h and 60 d of age divided by the total number of calves alive after 48 h of age. The herd-level preweaning mortality risk on sampled farms ranged from 0 to 15.9%, with an average of 2.8% (SD = 3.8%). A multivariable Poisson regression model was used to evaluate associations between 22 explanatory variables and preweaning mortality. Factors associated with greater herd-level preweaning mortality were larger herd size; having treatment protocols for diarrhea, pneumonia or navel infection written in collaboration with a veterinarian (compared with farms with the same treatment protocols developed without a veterinarian), and the herd-veterinarian never inquiring about calf health (compared with farms where the herd veterinarian inquired sometimes). Factors associated with lower herd-level preweaning mortality were using the calving pen for sick cows, having more than 4 people working with calves, offering calves a minimum volume of ≥9 L of milk/day, and farmers with a level of formal education higher than secondary school. These results indicate that producers may be able to reduce preweaning calf mortality by providing adequate labor for calf care, offering calves sufficient volumes of milk, being proactive in communicating with their veterinary practitioners about calf health, and potentially by engaging in continuous education.

Risk factors for the introduction of Salmonella spp. serogroups B and D into Dutch dairy herds

Salmonella spp. infections in animals are a concern due to their zoonotic nature, welfare effects and economic impact on the livestock industry. To enable targeted surveillance, it is important to identify risk factors for the introduction of Salmonella spp. in a herd. Since 2009, Dutch dairy processors require herds delivering milk to their plants to participate in a Salmonella programme. In this programme, bulk milk is tested three times a year (i.e. test rounds) by ELISA on presence of antibodies against Salmonella spp. serogroups B and D. Based on these bulk milk results we identified newly infected herds, and aimed to identify associated risk factors. Effects of putative risk factors for becoming newly infected were studied using a multivariable population average logistic regression (PA-GEE) model with binomial distribution. Per test round in 2019–2021, 0.85–4.10 % of the Dutch dairy herds at risk became newly infected, with large regional differences. Several risk factors for becoming newly infected in the context of the low herd-level prevalence were identified. The most evident risk factors that were identified were having at least one infected or recently recovered dairy herd within 500 m (OR = 2.67), on-farm presence of pigs (OR = 1.63), introduction of more than 2 cattle from other herds in the previous 12 months (OR = 1.17), being in an area with a relative soil moisture of >0.54 % (OR = 1.31), being located in an area with a high water surface area (>2 %; OR = 1.14) and a larger herd size (OR = 1.65). These results indicate that, in addition to introduction of cattle, local transmission plays an important role in the between-herd transmission of Salmonella spp. Information on risk factors for becoming newly infected based on regularly collected data, can be used to improve surveillance and to implement targeted control measures against salmonellosis.

Evolving Dairy Cattle Systems in Chile: Structural Shifts and Adaptation Strategies.

This study examines the structural and geographical changes in Chile's dairy cattle systems from 1997 to 2021, using data from agricultural censuses. It focuses on variables like animal stocks, herd sizes, pasture utilization, and stocking rates, analyzed through descriptive statistics, multivariable analysis, and geographical mapping. The findings show a significant decrease in dairy farms (-69%) and dairy cattle stocks (-25.4%), with regional disparities: southern farms increased in importance while central farms declined. There is a trend towards intensification, with higher stocking rates and larger herd sizes. Grassland utilization shifted, with a decrease in natural pastures and an increase in improved and sown pastures. The study identifies four typological groups based on stocking rates, dimensions, and pasture use, reflecting distinct evolutionary paths influenced by climate change, land use, economic dynamics, and technology. Geographical analyses highlight regional variations. This research provides insights into the dynamics of Chile's dairy farming sector and its sustainability challenges and opportunities amidst changing environmental and socioeconomic conditions.

Farm management practices and host species richness associated with higher likelihood of tuberculosis positive farms in Western Spain

Despite enormous efforts, complete animal tuberculosis (TB) eradication has only been achieved in few regions. Epidemiological analyses are key to identify TB risk factors and set up targeted biosecurity measures. Here, we conducted an in-depth characterization of 84 extensive beef cattle farms from a high TB prevalence region in Western Spain, and assessed how farm management and wildlife presence on farms contribute to cattle TB risk. Twenty-six out of 84 variables were associated with cattle farm TB positivity. Farm management variables associated with TB positivity included older cattle, larger herd size, highly fragmented farm structure and greater connectivity between farms. TB-positive farms provided supplemental feed over a higher number of months, used calf feeders, and had higher number of waterholes. Detecting Eurasian wild boar (Sus scrofa), red fox (Vulpes vulpes), European badger (Meles meles), roe deer (Capreolus capreolus), or Egyptian mongoose (Herpestes ichneumon) on cattle farms was also associated with farm TB positivity. The best ordinal regression model indicated that in farms with a large herd size (> 167 animals) the odds of being positive or recurrently positive (versus negative) was 7.34 (95% CI = 2.43–23.51) times higher that of farms with small herd size. Further, for every additional host species detected in the farm premises, the odds of being TB-positive increased 56%. We conclude that both cattle management and wildlife need to be targeted for successful TB control in grazing-based farming systems.

Impacts of rangeland ecological compensation on livelihood resilience of herdsmen: an empirical investigation in Qinghai Province, China

The increasing use of the payment for ecosystem services (PES) represents a prominent institutional shock triggered by external interventions on livelihoods of natural resource managers. To reconcile the needs for both conservation and development, a deep understanding on the influence mechanisms of PES on farmer livelihood resilience is paramount, particularly in dynamic and uncertain contexts. Taking the Rangeland Ecological Protection Subsidy and Reward scheme that has been implemented in pastoral China since 2011 as a case study, the paper empirically investigates the impacts of PES on livelihood resilience of livestock farmers in Qinghai Province. Based on a comprehensive evaluation of herder livelihood resilience from three dimensions—buffering, self-organizing and learning capacities, multiple linear regression was applied to examine the PES impacts. Resilience enhancement was mainly found in buffering capacity for herders with a medium to large herd size. Results of univariate parallel mediation models further reveal that household income growth and diversification and livestock upsizing were three key intermediary processes that mediated the enhancement and together contributed 28.83% of the total effect. The findings help narrow a knowledge gap in understanding whether, how and for whom PES contributes to improve farmer livelihood resilience. To achieve “win-win” outcomes, we stress that greater attention should be given to tailoring design and implementation of PES programs to align with the specificity of local contexts.

Swine influenza A virus infection dynamics and evolution in intensive pig production systems.

Swine influenza A virus (swIAV) is one of the main viral pathogens responsible for respiratory disease in farmed pigs. While outbreaks are often epidemic in nature, increasing reports suggest that continuous, endemic infection of herds is now common. The move towards larger herd sizes and increased intensification in the commercial pig industry may promote endemic infection; however, the impact that intensification has on swIAV infection dynamics and evolution is unclear. We carried out a longitudinal surveillance study for over 18 months on two enzootically infected, intensive, indoor, and multi-site pig production flows. Frequent sampling of all production stages using individual and group sampling methods was performed, followed by virological and immunological testing and whole-genome sequencing. We identified weaned pigs between 4 and 12-weeks old as the main reservoir of swIAV in the production flows, with continuous, year-round infection. Despite the continuous nature of viral circulation, infection levels were not uniform, with increasing exposure at the herd level associated with reduced viral prevalence followed by subsequent rebound infection. A single virus subtype was maintained on each farm for the entire duration of the study. Viral evolution was characterised by long periods of stasis punctuated by periods of rapid change coinciding with increasing exposure within the herd. An accumulation of mutations in the surface glycoproteins consistent with antigenic drift was observed, in addition to amino acid substitutions in the internal gene products as well as reassortment exchange of internal gene segments from newly introduced strains. These data demonstrate that long-term, continuous infection of herds with a single subtype is possible and document the evolutionary mechanisms utilised to achieve this.

Study of Milk Cost Production in Buffaloes of Telangana State

Background: Telangana state stands 13th position in milk production with 5.61 MT of milk production during 2019-20 as compared to 4.2 MT in 2014-15. The profitability of dairy enterprise is determined by sale price of milk and of late there is lot of uproar from farming community on lack of proper support price for milk. So having adequate data on cost of milk production in different sized farms in buffaloes will enable policy makers to arrive at a minimum support price for milk, so that the farmer will not be put to loss. Methods: An investigation was carried out to study the cost of milk production in buffaloes of dairy farmers in Karimnagar, Khammam and Rangareddy districts of Telangana. The data was collected from 240 farmers spread over 24 villages in 6 mandals in the selected districts. The 240 respondents were interviewed as per the questionnaire. Result: Average milk production per day per animal, sale price of milk per kg per animal per day was 8.63 lit, Rs.35.42 respectively. Cost of milk production in large, medium and small herd size was found to be Rs.26.32, Rs.26.68, Rs.27.08, respectively. Average cost of milk production per animal per day was found to be Rs.26.49. The average net income from cow was Rs.77.03. The average profit/litre of milk was calculated as Rs.8.92/lit. The average benefit-cost ratio was found to be 1.33.

Exploring policy options to transform traditional dairy system in Ethiopia: A system dynamics approach

Despite having a larger herd size and a favourable climate, Ethiopia generally lags behind developing nations in terms of both production and consumption of dairy products. For the purpose of finding and assessing ways to increase milk production by the traditional dairy system in Ethiopia's West Shewa zone, we integrated system dynamics (SD) modelling with a participatory model building approach. The main objective of the research was to develop SD model for West Shewa dairy value chain and apply it to assess ex-ante milk production and dairy household profit impacts of various interventions. The interventions evaluated in the study include enhanced urea treatment of crops residue, increased production of improved feed, and investment in more dairy cows. Analysis reveals that policies targeting feed development can boost milk production and household profits above the baseline. They also lead to a higher seasonal variability in milk production. Through the feed development strategy producers can achieve a 70 % and 735 % increase in milk production and household profit, respectively. However, the implementation of improved feed policy still leaves a gap in the average feed protein requirement of a dairy cattle in the study area. On the other hand, policy of increasing cow herd is not profitable. In addition, improved feed policy in drought results in reduced herd size, yet it leads to a higher milk output and household profit. Hence, with the feed development options explored in this study, increasing herd size is not a recommended course of action for improvement of the West Shewa dairy value chain. Therefore, future research should explore for further enhancement of the supply as well as quality of feed resources and the potential of investment in improved breeds.

Risk information sufficiency & seeking of southeastern United States beef producers

Of all cow-calf producers in the United States, one-third reside in the Southeast where operations face unique challenges and risks due to their geographical location. Cow-calf herds in the region are relatively small in terms of head counts as well as percentage of household incomes, making their operators less likely to participate in risk-reducing programs. Targeted risk communication is one way to help producers better understand and manage the multiple and complex risks they face. This study adapted the risk information seeking and processing model to inform a quantitative survey method that examined southeastern U.S. beef cow-calf producers’ perceived risks area knowledge gaps and the communication channels participants used to seek risk information. Participating producers were found to have gaps in knowledge for all risk areas in beef cow-calf management; the largest was economic and marketing/selling animals risks. No matter the risks area, producers prefer their risks information from magazines and Extension publications. Therefore, communication practitioners are encouraged to tailor risk management communications that help southeastern U.S. cow-calf producers fill their largest knowledge gaps in marketing/selling and economic risk management. Furthermore, this information is of the greatest need for producers with more beef production experience and larger herd sizes. Magazines and Extension publications offer communicators the best channels to readily reach southeastern U.S. cow-calf producers as this is where they are currently seeking risks information.

Seroprevalence and related risk factors of Brucella spp. in livestock and humans in Garbatula subcounty, Isiolo county, Kenya.

Brucellosis is a neglected zoonotic disease that affects both animals and humans, causing debilitating illness in humans and socio-economic losses in livestock-keeping households globally. The disease is endemic in many developing countries, including Kenya, but measures to prevent and control the disease are often inadequate among high-risk populations. This study aimed to investigate the human and livestock seroprevalence of brucellosis and associated risk factors of Brucella spp. in a pastoralist region of northern Kenya. A cross-sectional survey was conducted using a two-stage cluster sampling method to select households, livestock, and humans for sampling. Blood samples were collected from 683 humans and 2157 animals, and Brucella immunoglobulin G (IgG) antibodies were detected using enzyme-linked immunosorbent assays. A structured questionnaire was used to collect data on potential risk factors associated with human and animal exposures. Risk factors associated with Brucella spp. exposures in humans and livestock were identified using Multivariate logistic regression. The results indicated an overall livestock Brucella spp. seroprevalence of 10.4% (95% Confidence Interval (CI): 9.2-11.7). Camels had the highest exposure rates at 19.6% (95% CI: 12.4-27.3), followed by goats at 13.2% (95% CI: 9.3-17.1), cattle at 13.1% (95% CI: 11.1-15.3) and sheep at 5.4% (95% CI: 4.0-6.9). The herd-level seroprevalence was 51.7% (95% CI: 47.9-55.7). Adult animals (Adjusted Odds Ratio (aOR) = 2.3, CI: 1.3-4.0), female animals (aOR = 1.7, CI: 1.1-2.6), and large herd sizes (aOR = 2.3, CI: 1.3-4.0) were significantly associated with anti-brucella antibody detection while sheep had significantly lower odds of Brucella spp. exposure compared to cattle (aOR = 1.3, CI: 0.8-2.1) and camels (aOR = 2.4, CI: 1.2-4.8). Human individual and household seroprevalences were 54.0% (95% CI: 50.2-58.0) and 86.4% (95% CI: 84.0-89.0), respectively. Significant risk factors associated with human seropositivity included being male (aOR = 2.1, CI:1.3-3.2), residing in Sericho ward (aOR = 1.6, CI:1.1-2.5) and having no formal education (aOR = 3.0, CI:1.5-5.9). There was a strong correlation between human seropositivity and herd exposure (aOR = 1.6, CI:1.2-2.3). The study provides evidence of high human and livestock exposures to Brucella spp. and identifies important risk factors associated with disease spread. These findings emphasize the need for targeted prevention and control measures to curb the spread of brucellosis and implement a One Health surveillance to ensure early detection of the disease in Isiolo County, Northern Kenya.

Population distribution and breeding practices of livestock in different districts of Bangladesh

The objectives of this study were to determine the farmers’ socio-economic characteristics, livestock population dynamics, and breeding practices followed by the farmers. Out of 1487 farmers, a major proportion (53.12%) of farmers was middle-aged. Most of the farmers (71.22%) were associated with agricultural activities and had low income per month (52.32%). Livestock keeping patterns of farmers were cattle, goats, buffalo, and combinations of these animals. Female animals were inferred to be more prevalent in different districts (cow 85.08%, doe 81.29%) than males (bull 14.92%, buck 18.71%). In case of cattle and goats, the highest number of farmers maintained a medium size herd, whereas buffalo farmers had a large herd size. In terms of breeding practices, the majority of the farmers (75.55%) performed artificial insemination (AI) in cattle and found it convenient to service their cows. When considering buffalo, and goat, the majority of the farmers (94.12% and 98.50%, respectively) practiced natural services. The findings also demonstrated that the majority of the farmers (73.8% and 82%, respectively) raised crossbreed cattle and buffalo, while just a tiny portion (26.18% and 18%, respectively) raised indigenous breeds. However, this situation was vice versa in case of goat. For choice of the breed according to the farmers, 39.17% of farmers preferred Black Bengal goat, 60.83% preferred cross breed. This study represents a comprehensive overview of livestock status and existing breeding practices employed by the farmers in different districts of Bangladesh, which may be utilized to implement relevant livestock improvement programs in Bangladesh. Asian Australas. J. Biosci. Biotechnol. 2023, 8(3), 38-48

Outdoor access practices in the Canadian dairy industry

Dairy cows are highly motivated to access pasture and have a partial preference for alternative forms of outdoor access (e.g., deep-bedded outdoor sand or wood-chip packs). In addition, Canadians value the provision of outdoor access to dairy cows as they perceive it as important for good cow welfare. In contrast to Europe, Oceania, and the USA, little data exist on the use of outdoor access on Canadian dairy farms. Therefore, our objective was to assess current outdoor access practices for dairy cows in Canada. An online questionnaire was used to determine housing and outdoor access practices for lactating cows, dry cows, pregnant heifers, and weaned, nonpregnant heifers on Canadian dairy farms. The questionnaire was distributed by the 10 provincial milk boards between November 2020 and August 2021, resulting in an 8.9% response rate (n = 903 completed questionnaires). In total, 75% (n = 675) of respondents provided some form of outdoor access to at least 1 cattle class on their farm. Pasture was the most frequently used form of outdoor access for all cattle classes. A total of 28 and 44% of Canadian dairy farms provided lactating and dry cows, respectively, access to pasture whereas for youngstock, these numbers were 44 and 24% for pregnant heifers and weaned, nonpregnant heifers, respectively. Herd size (for each cow class), indoor housing system, and region were all associated with the provision of pasture. Farms with larger lactating herds less often provided access to pasture; larger herd sizes in terms of weaned, nonpregnant heifers, pregnant heifers, and dry cows were also associated with a lower likelihood of access to pasture. Farms using indoor bedded pack housing for their lactating cows more often provided pasture to this cattle class than farms with freestall or tiestall housing; this likelihood did not differ between farms with tie or freestall housing for this cattle class. Dry cows or pregnant heifers housed in a tiestall were more often provided pasture than freestall-housed dry cows or pregnant heifers. Housing type for weaned, nonpregnant heifers was not associated with the likelihood of pasture provision. Farms in British Columbia or on Canada's East Coast (i.e., Nova Scotia, New Brunswick, and Prince Edward Island) more often provided lactating cows pasture compared with farms in other regions. For the other 3 cattle classes, farms on the East Coast of Canada more often provided pasture than farms in other parts of Canada. These results will inform future decisions regarding outdoor access for Canadian dairy cattle and may also aid in identifying future areas of research. For example, our results may aid in designing housing systems that facilitate outdoor access in larger herds and in areas that are subject to more extreme weather conditions.

Rotational grazing with cattle‐free zones supports the coexistence of cattle and wild herbivores in African rangelands

Abstract African wildlife populations are declining at an alarming rate. To stop further population declines and restore ecosystems, more areas for wildlife are needed. Community‐based conservation with wildlife‐livestock coexistence in the vast rangelands of Africa presents a major opportunity. However, the efficacy of wildlife conservation in mixed land‐use areas remains an outstanding question. To assess the ecological outcomes of land‐sharing between regulated livestock herds and wildlife populations in African savannas, we test how rotational cattle grazing affects spatiotemporal dynamics of 15 large herbivore species in the Maasai Mara, Kenya. First, we tested how wild herbivore distributions across the Greater Mara Ecosystem (the Mara, ~2600 km2) are related to cattle density and environmental variables using 584,561 observations of wild herbivores (ecosystem scale). In a second analysis, we tested how rotational cattle grazing affects wild herbivore distributions in a 300 km2 subsection of the Mara using 30,583 observations (landscape scale). Finally, we tested how functional traits of wild herbivores affect species‐level spatiotemporal responses to cattle grazing. At the ecosystem scale, the presence of five wild herbivore species was positively correlated with cattle density, while cattle effects on wild herbivore abundances were species‐dependent with both increases and decreases. At the landscape scale, rotational cattle grazing strongly impacted the spatiotemporal habitat selection of wild herbivores, resulting in distinct lag periods with which different species are attracted to areas previously grazed by cattle. These lag periods were linked to functional traits, with body mass and herd size explaining 35% of the interspecific differences. Small to medium‐sized herbivores with large herds select areas recently grazed by cattle, whereas large species with large herd sizes and small species with small herd sizes avoid recently grazed areas. Synthesis and applications: Our results revealed that the effect of cattle on wild herbivores varies considerably among species, suggesting that cattle‐wildlife interactions range from facilitation to competition. To maintain species that strongly avoid cattle, designated livestock‐free zones remain essential, also in rotational grazing systems. Rotational grazing systems with regulated livestock densities present an important opportunity to better manage wildlife‐livestock coexistence and thus improve wildlife conservation in African rangelands.

An evaluation of parameters which affect dairy herd movement on Irish pasture-based farms

AbstractIn pasture-based grazing systems, farm roadways are a pivotal link to connect paddocks on the grazing platform to the milking parlour. However, their effectiveness in the efficient movement of the dairy herd between the grazing paddocks and the milking parlour has yet to be fully quantified. A validation experiment was conducted on a research farm to analyse characteristics on farm roadways that may affect cow throughput, which was observed as the number of cows per minute (CPM) passing a specified location. Roadway width (R2 = 0.96) and surface condition score (SC) (R2 = 0.78, respectively) were both positively associated with CPM. Public road crossings imposed a 32.7% reduction in CPM in this study. CPM increased from 12.4 CPM on a one-metre-wide roadway with a SC of Index 1 to 107.6 CPM on a five-metre roadway with a SC of Index 5. This exercise allowed for CPM on commercial farms to be predicted. Farm roadways were examined across 55 Irish dairy farms. Greater roadway width, reduced verge width and greater water run-off were each associated with higher SC on commercial farms. Larger herd sizes had a lower CPM relative to herd size in contrast to smaller herd sizes, resulting in a significantly longer total time to move the dairy herd through any specific point on the farm roadway network. The findings from this study have quantified the parameters which affect both CPM on commercial farm roadways and parameters which may be associated with SC on commercial farm roadways.

Trends and factors associated with dairy calf early slaughter in Ireland, 2018-2022.

Dairy systems require that each cow calves annually to have an efficient milk production cycle. In systems where milk production is maximized, the male offspring from dairy breed sires tend to have poor beef production traits and, therefore, can be of low economic value. Few studies have been published on the factors impacting early slaughtering of calves in peer-reviewed literature. Here we present an analysis of national data on calves slaughtered from 2018 to 2022 in Ireland. Data (Jan 2018-May 2022) on all cattle <6 months of age were collated at a national level and were described at calf-, herd-, and county-levels. These data were statistically analyzed at per-capita slaughter rates (calves/calf born) using negative binomial regression models with an offset. There were 125,260 calves slaughtered early (1.09% of total births) recorded in the dataset from 1,364 birth herds during the study period, of which 94.8% (118,761) were male. 51.7% were classified as Friesian-cross (FRX), 11.5% Friesian (FR) and 32.1% Jersey-cross (JEX). The median age at slaughter was 16 days (Mean: 18.9 days; IQR: 13-22). The median calves/herd slaughtered was 16 (mean: 91.8); median calves/herd/year slaughtered was 21 (mean: 42.0). There was substantial variation in counts of calves slaughtered across herds, years, and counties. Herd calf slaughter rates and per capita calf slaughter rates increased significantly in 2022, with the highest rates over the time series. Calf slaughter rates varied significantly with herd size, year, and major breed (Jersey; JE). Herds which were more recently established tended to have higher calf slaughter rates. Herds that repeatedly slaughtered calves over 2 or more years tended to be larger and slaughtered more calves/herd/year. The slaughtering of calves is not widespread across the dairy industry in Ireland. The distribution of calves slaughtered per herd demonstrate that a small number of herds contributed disproportionately to calf slaughter numbers. Such herds tended to be very large (herd size), more recently established (2016 onwards), and have higher proportions of JE/JEX breed cattle. The outcomes of the present study provide an evidential base for the development of targeted industry-lead interventions with the aim of ending the routine early slaughter of calves.

Influence of dairy farmers’ knowledge on their attitudes towards breeding tools and genomic selection

Understanding farmers' attitudes towards traits is critical for developing appropriate breeding goals for dairy production. In response to a research gap in regards to the influence of farmers' knowledge of breeding tools, this study aimed to determine the effect of farmers' knowledge on their attitudes towards the use of breeding tools and traits in typical family-owned farms in Slovenia. An online questionnaire was sent to dairy farmers affiliated with Slovenian breeding associations, and 256 dairy farmers responded. The analysis was conducted in three steps. First, the basic response patterns according to the farmers' knowledge level were determined using latent class analysis. Second, farmers' attitudes towards breeding tools were assessed by 15 statements using principal component analysis. Finally, we were interested in the relationship between farmers' attitudes and knowledge about selection. The results showed that farmers had more knowledge about the benefits of genomic selection, followed by general knowledge about breeding values and the definition of genomic selection, and they had the least knowledge about the reference population. Farmers with more knowledge were statistically significantly more likely than farmers with less knowledge to have higher education, be younger, have a larger herd size, have higher milk production per cow, have the intent to increase herd size and milk quantity, and use genomically tested bulls. No significant relationship was found between belonging to a specific knowledge class and the main breed in the herd, the farmer's gender, production system, or farming in less-favoured areas. The results also show that farmers basically agree that they need written recorded performance data about a bull/cow to know exactly how good the animal is, that the genetic merit (breeding value) of bulls/cows adds to the performance of their progeny, that it is very important to maintain the breed characteristics of bulls/cows, that cooperation in being able to compare animals with other farmers is essential for improving herd performance, and that the possibilities of selecting dairy cows with genomic selection and monogenetic traits must be fully exploited, indicating a positive attitude towards genomic selection. The level of knowledge was shown to influence attitudes towards various aspects of breeding. It was found that the higher the level of knowledge, the more positive the attitude towards genetic and genomic selection, and the more negative the attitude towards traditional selection.

Foot and Mouth Disease in Adama and Boset districts, East Shewa zone, Ethiopia: Seroprevalence and Virus serotyping

Foot and mouth disease (FMD) is consistently ranked as the most economically important viral disease, and ranks among the top five important livestock diseases in Ethiopia. The status of FMD is barrier for the international trade of livestock and livestock products; thus, continuous epidemiological studies are necessary to develop efficient control strategies. This study determined the seroprevalence of FMD, associated risk factors for its occurrence, and FMD serotypes in the Adama and Boset districts of the East Shewa zone of Oromia Regional State, Ethiopia. A total of 305 blood samples were randomly collected from cattle and subjected to a 3ABC enzyme-linked immune-sorbent assay (ELISA) to detect antibodies against non-structural proteins of FMD virus (FMDV) and Solid-Phase Competitive ELISA for FMDV serotype identification. Evaluation of the associated risk factors was conducted using a multivariable logistic regression model. In this study, an overall seroprevalence of 28.2% (95% CI: 25.7% - 36.2%) was recorded. The risk of being FMD positive was significantly higher in exotic crossbreds [38.60%; OR= 2.23 (95% CI: 1.34 – 3.71); p&lt;0.001] as compared to local breeds. The seroprevalence of FMD was significantly higher in large herd sizes [54.41%; OR=4.2 (95%CI: 3.05 - 15.87), P &lt; 0.001] compared to medium and small herd sizes. Three FMD serotypes namely serotype O, A, and SAT-2 were identified. Besides, mixed serotypes O and A, serotypes O and SAT-2, serotypes A and SAT-2, and serotypes A, O, and SAT-2 were recorded. By considering the detection of multiple serotypes of the FMDV and the lack of cross-protection among the serotypes, the use of polyvalent FMD vaccine against the serotypes of the virus circulating under field conditions is highly recommended.

Seroprevalence and Factors Associated with Toxoplasma gondii, Neospora caninum, and Besnoitia besnoiti Infections in Cattle and Goats in Selangor, Malaysia.

Apicomplexan parasites such as Toxoplasma gondii, Neospora caninum, and Besnoitia besnoiti are widely recognized as causes of production diseases in ruminants. This study aimed to investigate the serological occurrence of T. gondii, N. caninum, and B. besnoiti in cattle and goats from smallholder farms in Selangor, Malaysia. A cross-sectional study was conducted on 19 farms by collecting 404 bovine (n = 225) and caprine (n = 179) serum samples, which were then essayed for T. gondii, N. caninum, and B. besnoiti antibodies using commercially available ELISA test kits. Farm data and animal characteristics were documented, and the data were analyzed using descriptive statistics and logistic regression models. The seroprevalence of T. gondii at animal and farm levels in cattle was 5.3% (95% CI 1.2-7.4%) and 36.8% (95% CI 22.4-58.0%), respectively. Animal-level seropositivity for N. caninum was 2.7% (95% CI 0.4-4.2%) and 5.7% for B. besnoiti (95% CI 1.3-9.4%) with corresponding farm-level seropositivity of 21.0% and 31.5%, respectively. For the goat samples, a high animal- (69.8%; 95% CI 34.1-82.0%) and farm-level (92.3%) seropositivity was recorded for T. gondii, but was relatively lower for N. caninum antibodies, at 3.9% (95% CI 1.5-6.2%) and 38.4% (5/13). The factors associated with T. gondii seropositivity were older animals (above 12 months) (OR = 5.3; 95% CI 1.7-16.6), semi-intensive farms (OR = 2.2; 95% CI 1.3-6.2), the presence of either dogs or cats (OR = 3.6; 95% CI 1.1-12.3), a large herd size (>100 animals) (OR = 3.7; 95% CI 1.4-10.0), and a single source of replacement animals (OR = 3.9; 95% CI 1.6-9.6). These findings are vital in developing effective control measures against these parasites in ruminant farms in Selangor, Malaysia. More national epidemiological research is required to elucidate the spatial distribution of these infections and their potential impact on Malaysia's livestock industry.