Pastoralism Research Articles

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.

An application for mobile devices as a decision support for the treatment and prevention of bovine fasciolosis - A survey among organic dairy farms in Bavaria

Based on health applications used in human medicine for the self-management of chronic diseases, the aim of this study was to evaluate a mobile app in veterinary medicine using the example of a decision-making aid for the control and prevention of bovine fasciolosis on dairy cattle farms. The study was carried out on 37 organic dairy cattle farms in Bavaria. The farms were divided into two groups: one group received a mobile app (n=17) as a decision-making aid, while the other group received a printed brochure (n=20) with identical content. At the beginning of the study, all participants were questioned by telephone concerning their farm, among other things. After using the respective tool, the participants were again interviewed by telephone. At the beginning of the study, the majority of participants were aware of the options for drainage (n=28; 75.7%) and fencing off wet areas (n=36; 97.3%). 37.8% (n=14) stated that they were familiar with a pasture rotation system. After using the respective aid, the majority of participants described the tool as helpful (94.1% app; 80% brochure). Many participants (app group: n=10 (58.8%); brochure group: n=16 (80%)) stated that they wanted to change their approach based on the new knowledge gained, e. g. introducing a pasture rotation system (app group: n=9 (52.9%); brochure group: n=13 (65.0%)). Both study groups enjoyed working with the tool they used. They viewed the knowledge imparted by the mobile app or brochure as helpful and useful. Most participants expressed a desire to continue using these tools in animal health management on farms in the future. The use of tools such as mobile apps may improve veterinary advice, e. g. in the management of parasitoses in cattle herds.

A Study of the Cereal Benches Based System for Protection of Soil in Algerian Oued Mellegue Tebessa Dry Lands

The study was intended to mitigate the destructive after-effects of erosion, where runoff water erodes the arable layers through the increased transport of soil particles. The study was conducted in Ain Zerga across 40 plots, covering an area of 405 hectares, during 2023 and 2024, with a focus on the dimensional evaluation of cereal beds. The evaluation mainly focused (a) on the durability of the structure, including the measurement of settlement, which indicates distribution and strength of resistance to climatic hazards, and (b) proportional sustainability and the interbank aspects. The height of benches, at 0.481± 0.086 m, and the length of 82.583 ± 24.203 m were influenced by height differences and the intensity of water flows. The retention of runoff water was influenced by the slope toward the natural spillway. Furthermore, the destructive intensity of the runoff, amplified by the sharp increase in altitude, was confirmed by statistically significant differences in the length, height, and number of cracks between the study sites (p-value = 0.000). The number of cracks per breach at the Gastel site (4.25 units) and Kef Mebdoua (3.917 units) was higher compared to Ain Zerga, Berket Frass, Ouled Mebarek, and Zlassde, where the number ranged from 0.750 to 1.583 units. The statistical significance in the number of cracks (p<0.001) signified that variation in cracks between the locations was due to the topographic steep slopes on site. The non-significant difference in width suggests that the observed differences could be due to the phenomenon of compaction following the annual infiltration of water on the ridges of cereal bench, plus the act of trampling constantly exercised by sheep and cattle herds when passing to the paths. This work proposed in this article is an attempt to structure a chain of impact analysis of risks and vulnerability of intensity via the sustainability of cereal bench carried out in the Tebessa region.

WITHDRAWN: First report of Toxocara vitulorum infection in a dairy calf in Tennessee

The ascarid nematode, Toxocara vitulorum is a destructive parasite of ruminants with a world-wide distribution that causes mortality in calves, especially those with poor nutrition. Reports of Toxocara vitulorum are scarce in the continental United States and Canada. A single gravid female T. vitulorum was discovered on the necropsy of a 2.5-month-old mini jersey calf from a dairy farm in Sparta, TN. Genetic analysis of the 18S and COI genes revealed a 100 % match to T. vitulorum samples isolated from beef calves in Iowa and a 96.73 % match to T. vitulorum isolated from a yak in Austria, respectively. Although perforation of the small intestine was seen in the calf and is the typical cause of death in calves with high burdens of this worm, it is unknown if this single nematode infection contributed to the cause of death in this case. The source of the infection in this calf also remains unknown. Fecal centrifugal flotations on the rest of the herd (n = 8) did not produce any T. vitulorum eggs, even in the 2 calves that were under 6 months old on the farm. We were unable to obtain milk to test for T. vitulorum larvae from the calf's mother. This is the first report of T. vitulorum in dairy calves in the US and the first report of this parasite in Tennessee. Given the devastation caused by this parasite in cattle and bison herds in other countries, further studies to determine the prevalence and pathogenicity of this parasite in the US are vital to prevent spread of this parasite to other vulnerable species and to prevent economic losses in the animal industry.

Study on fungal contaminants in aborted calves of cattle herds in Iran.

Abortions in livestock herds are a major contributor to economic losses. The incidence of fungal aetiology has been reported thus far. The purpose of this study is to investigate the prevalence of abortions due to fungi in referred cases to the Center of Excellence in Ruminant Abortion and Neonatal Mortality, Veterinary Hospital of Ferdowsi University of Mashhad, Mashhad, Iran, from different provinces of Iran. A total of 200 calves were referred between 2018 and 2022. Samples were taken from the lungs, liver, spleen and abomasum. The fungi present in the cultures were analysed microscopically and morphologically. There were varying contamination levels in the liver, spleen and lungs, with prevalence ranging from 15% to 17%. Abdomasum had a 1% prevalence rate. Different fungal species, including Cryptococcus neoformans (C. neoformans), Aspergillus spp., Rhodotorula spp., Trichosporon spp., Candida spp., Geotrichum spp., Penicillium spp. and Mucor spp., were identified, indicating a diverse range of pathogens affecting calves. The specificity of fungal contaminants in certain organs, such as C. neoformans, Rhodotorula spp. and Trichosporon spp., highlighted the organ's microenvironment as a potential factor influencing fungal growth. As fungi are emerging as a significant cause of morbidity and mortality in animals, the growing role of fungi in livestock abortions should be investigated. As clinical signs are not pathognomonic, laboratory help is imperative to confirm fungal abortion diagnosis.

Screening for Japanese Black cattle herds at risk of bovine leukemia virus transmission based on the presence of persistent lymphocytosis

This study aimed to develop a screening method to identify Japanese Black (JB) cattle farms at high risk of bovine leukemia virus (BLV) transmission. We introduced a recently established lymphocyte count (LC) cut-off to detect cattle with persistent lymphocytosis (PL). To identify high-risk farms, we examined the relationship between the proportion of cattle with PL and the mean blood proviral loads (PVL) per farm. The results showed a strong correlation between the proportion of cattle with high LC, higher than the LC cut-off values for JB cattle, and the mean blood PVL per farm. This indicates that the mean blood PVL on a herd basis of JB cattle can be estimated from the proportion of cattle with high LC. Specifically, the mean blood PVL on farms with >30 % cattle having high LC was estimated to be greater than 100 copies/10 ng DNA. The higher the proportion of cattle with high LC per farm, the higher the proportion of cattle at risk as sources of BLV infection. The study demonstrated that the proportion of cattle with high LC, based on the new LC cut-off, serves as a practical index for screening high-risk farms with PL cattle that have high PVL. This finding is meaningful for prioritizing farms with a high proportion of cattle with high LC, necessitating BLV infection prevention measures, such as voluntary culling and segregation, in order to develop a regional, stepwise BLV eradication strategy.

Advances in the Characterization of Creole Cattle from Nayarit, Chihuahua, and Baja California Sur.

Objective. This manuscript aims to contribute to disseminating the research conducted on creole cattle from Nayarit, Chihuahua, and Baja California, as these regions have been the focus of numerous studies. These studies include identifying the areas of opportunity that need to be addressed for the conservation of this zoogenetic resource present in Mexico. Description. Cattle farming in Mexico began with the arrival of the first bovines from the Iberian Peninsula to New Spain over 500 years ago. These cattle established itself in various regions of the country, developing specific characteristics that have allowed it to adapt primarily to harsh environmental conditions. As a result, these bovines are considered a productive alternative in various agroecological environments to address the challenges of climate change and mitigate the negative effects on the ecosystem. Limitations. To date, research on the morphological, productive, and genetic characterization, as well as the production environment of Creole cattle in Mexico, remains limited. Therefore, it is necessary to develop studies in this area to contribute to the conservation of this resource and, above all, to identify mechanisms for its rational use that justify its existence in a modern economic and productive environment. Conclusions. The documentary review conducted to present the current state of research on creole cattle herds in Nayarit, Chihuahua, and Baja California Sur revealed that the studies have primarily focused on productive aspects in various environments. Therefore, it is necessary to encourage research directed towards other productive areas of cattle, such as reproduction, animal health, and adaptation, in order to develop strategies that contribute to the conservation of this zoogenetic resource.

Microbiological and genetic typing of atypical mycobacteria identified in the Novosibirsk region

219 samples of biological material from animals and 54 samples of environmental objects from farms in the Novosibirsk region, which are free from bovine tuberculosis, were examined for isolation of the tuberculosis pathogen, microbiological and genetic typing of isolated cultures of atypical mycobacteria. Microbiologic diagnosis included culture method, biochemical tests and biological assay. During the treatment of animal biomaterial 50 cultures were isolated, and 20 cultures were isolated from the environmental objects. The isolated cultures were classified as mycobacteria on the basis of their culture and morphological properties and bacterioscopy. According to biochemical characteristics, out of 70 cultures studied, 27 isolates (38.6%) belonged to atypical mycobacteria of different species. Of these, 26 cultures (96.3%) were categorized as Group III and 1 culture (3.7%) as Group IV according to Runyon's classification. Next, a biological assay was performed by infecting nonlinear white mice with suspensions of 27 identified cultures of atypical mycobacteria. At autopsy and pathological-anatomical study of laboratory animals, changes in internal organs characteristic for tuberculosis were not found, which confirms that the cultures under study belong to atypical mycobacteria. Molecular systematization of the isolated cultures revealed the presence of Mycobacterium avium (20 cultures, 74%), M. nonchromogenicum (5 cultures, 18.5%), M. intracellulare (1 culture, 3.7%) and M. fortuitum (1 culture, 3.7%). Thus, based on the results of a comprehensive study of 70 cultures of atypical mycobacteria isolated from animal biomaterial and environmental objects from the territory of farms in the Novosibirsk region, free from bovine tuberculosis, 27 isolates belonging to atypical mycobacteria of groups III and IV were identified according to Runyon’s classification. On the basis of typing, it was found that the leading role among the identified pathogens is occupied by atypical mycobacteria of group III, in particular M. avium. The etiology of nonspecific tuberculin reactions in tuberculosis-free herds of cattle can be explained by the isolation of atypical Mycobacterium tuberculosis groups III and IV according to Runyon classification from environmental objects and their persistence in the organism of healthy animals.

A Quadruple Gene-Deleted Live BoHV-1 Subunit RVFV Vaccine Vector Reactivates from Latency and Replicates in the TG Neurons of Calves but Is Not Transported to and Shed from Nasal Mucosa.

Bovine herpesvirus type 1 (BoHV-1) establishes lifelong latency in trigeminal ganglionic (TG) neurons following intranasal and ocular infection in cattle. Periodically, the latent virus reactivates in the TG due to stress and is transported anterogradely to nerve endings in the nasal epithelium, where the virus replicates and sheds. Consequently, BoHV-1 is transmitted to susceptible animals and maintained in the cattle population. Modified live BoHV-1 vaccine strains (BoHV-1 MLV) also have a similar latency reactivation. Therefore, they circulate and are maintained in cattle herds. Additionally, they can regain virulence and cause vaccine outbreaks because they mutate and recombine with other circulating field wild-type (wt) strains. Recently, we constructed a BoHV-1 quadruple mutant virus (BoHV-1qmv) that lacks immune evasive properties due to UL49.5 and glycoprotein G (gG) deletions. In addition, it also lacks the gE cytoplasmic tail (gE CT) and Us9 gene sequences designed to make it safe, increase its vaccine efficacy against BoHV-1, and restrict its anterograde neuronal transport noted above. Further, we engineered the BoHV-1qmv-vector to serve as a subunit vaccine against the Rift Valley fever virus (BoHV-1qmv Sub-RVFV) (doi: 10.3390/v15112183). In this study, we determined the latency reactivation and nasal virus shedding properties of BoHV-1qmv (vector) and BoHV-1qmv-vectored subunit RVFV (BoHV-1qmv sub-RVFV) vaccine virus in calves in comparison to the BoHV-1 wild-type (wt) following intranasal inoculation. The real-time PCR results showed that BoHV-1 wt- but not the BoHV-1qmv vector- and BoHV-1qmv Sub-RVFV-inoculated calves shed virus in the nose following dexamethasone-induced latency reactivation; however, like the BoHV-1 wt, both the BoHV-1qmv vector and BoHV-1qmv Sub-RVFV viruses established latency, were reactivated, and replicated in the TG neurons. These results are consistent with the anterograde neurotransport function of the gE CT and Us9 sequences, which are deleted in the BoHV-1qmv and BoHV-1qmv Sub-RVFV.

Comparative Evaluation of the Antibiotic Resistance Profile of Staphylococcus aureus Isolated From Breeders and Livestock.

Animals are a potential source of Methicillin Resistant Staphylococcus aureus. This study evaluated the antibiotics susceptibility pattern of S. aureus isolates from breeders and livestock. S. aureus strains were isolated from 180 livestock and 48 livestock farmers and identified using standard methods. Antibiotic susceptibility profiles and MRSA status were determined via disk diffusion susceptibility method. Among farm workers, 37.5% were colonized by S. aureus, with pig farm workers exhibiting the highest prevalence (56.2%), cattle herders (37.5%), and goat farm workers (18.7%). MRSA carriage among livestock isolates was 41.3%, while, six isolates from the poultry farm worker were MRSA, representing a carriage of 33.3%. Drug susceptibility profiles revealed differential patterns between isolates from breeders and animals. Gentamicin and levofloxacin demonstrated higher efficacy against farm worker isolates compared to animal isolates. Resistance to cefuroxime was higher among animal isolates (84.1%) as against the 66.7% for the breeders. The identification of multidrug-resistant S. aureus strains underscores the risk posed to humans in contact with animals. These findings stress the importance of monitoring and managing MRSA transmission between animals and humans.

77 Differences in carcass quality and meat quality between cattle of different breed types

Abstract Crossbreeding cattle in the beef industry is a common practice to improve production and increase profitability. Introducing Bos indicus (BI) genetics into cattle herds is one potential method to improve production, as they are able to withstand higher temperatures, are better adapted to nutritional stress, and consume less water than Bos taurus (BT) cattle. However, introduction of BI genetics is known to decrease both carcass and meat quality compared with those from BT cattle. As such, the objective of this study was to determine how crossbreeding commercial Angus cows with Santa Gertrudis bulls to incorporate BI genetics impacts carcass and meat quality of the resultant offspring. This study utilized 38 steers of two different breeds: Angus (AN; n = 29; 100% BT) or Santa Gertrudis influenced (SG; n = 9; 19% BI, 81% BT). All steers were fed the same typical ration and harvested at a commercial facility once industry average body weight and backfat standards were met. Hot carcass weight (HCW), ribeye area (REA), yield grade (YG), and marbling scores were collected at harvest. Individual loins were collected for meat quality analysis. Meat quality data were collected after 14 d of wet aging at 4˚C. Meat color data was collected on d 0, 3, and 7. Statistical analysis was done using the MIXED procedure of SAS to assess the main effect of breed. Color analysis was conducted with day as a repeated measure. Least squares means were separated using Tukey-Kramer adjustments. Angus cattle had an increased (P = 0.009) REA and tended to have a reduced (P = 0.06) YG than SG cattle. However, no differences (P ≥ 0.13) between breeds were observed in HCW or marbling score. Additionally, no differences (P ≥ 0.08) were observed in meat quality (pH, drip loss, cook loss, Warner-Bratzler Shear Force, or Texture Profile Analysis) between breeds. There was not a day x breed (P > 0.65) or breed (P ≥ 0.57) effect for L*, a*, or b* color values. Day affected (P = 0.008) L*, a*, and b*, such that a* and b* both increased on d 3, then decreased on d 7, while L* increased on d 3 and remained consistent until d 7. These results are promising as they indicate there may not be differences in carcass quality and meat quality when utilizing this method to introduce BI genetics into a traditional BT production system. As such, this could be a useful tool in managing production systems in our beef herds. However, future research with a larger sample size will be necessary to gain more conclusive results.

PSVII-4 A novel deletion in exon 3 of the myostatin (MSTN) gene is identified in a Raramuri criollo cattle herd

Abstract Several polymorphisms in the coding region of the myostatin (MSTN) gene have been associated with the double-muscled (DM) phenotype in different species. An experimental herd of purebred Raramuri criollo cattle in Chihuahua, Mexico, has been selectively managed for beef production during the last 15 yr. Recently, two calves where visually identified as DM animals. The aim of this study was to identify changes in the MSTN gene sequence, associated with the two DM individuals and to screen for carriers of the potential polymorphisms within this herd. The DM paternity of the calves was verified by the SeekSire bovine parentage testing of NEOGEN (Lincoln, NE). A 6.6 Kb fragment of the MSTN gene were amplified by PCR and sequenced using Illumina DNA prep kit in a MiniSeq platform. The resulting reads were analyzed using different bioinformatic programs. SNPs were generated in VCF files and filtered by the following criteria: variant confidence normalized by depth of variant samples (QD) < 2.0, mapping quality (MQ) < 40.0, strand bias(FS) > 60.0. The deduced myostatin protein and the three-dimensional model were obtained with bioinformatic tools. Once a novel variant was identified, a real-time PCR protocol was developed to genotype 100 and 97 herdmates, the allelic and genotypic frequencies were estimated. A 9-bp deletion was identified at the same position as the 11-bp deletion (g.821to 831del11) of the Belgian Blue MSTN allele (Figure 1). Although the latter allele has been found in three Spanish cattle breeds ancestrally related to Raramuri criollo, this is the first report of the 9-bp deletion in the MSTN gene. Such deletion results in the loss of three highly conserved amino acids residues (274, 275 and 276) in MSTN, but does not lead to a premature stop codon as in the case of the 11-bp deletion characteristic to DM Belgian Blue. The in silico three-dimensional MSTN conformation obtained for this allele has some structural differences compared with the protein reference model. The allelic frequencies were 0.85 and 0.15 for the MSTN+ and MSTNdel alleles, respectively, whereas the genotypic frequencies were 0.71, 0.01 and 0.28 for MSTN+/MSTN+, MSTNdel/MSTNdel MSTN+/MSTNdel genotypes, respectively. Controlled mattings to generate different genotypes in the research herd would allow to continue studying the effects of this MSTN gene variant on productive performance, forage behavior, husbandry and carcass and meat quality traits known to be affected by the DM phenotype in beef cattle.

7 Role of the preovulatory follicle in oocyte metabolic and developmental competence for pregnancy

Abstract A majority of bovine pregnancy loss occurs in the first 7 d of gestation. The oocyte is a key driver of embryo viability during this time, and its competence for embryo development and pregnancy establishment is greatly influenced by the surrounding microenvironment during oocyte maturation. Assisted reproductive technologies allow for more efficient propagation of superior genetics and improved reproductive management of the cattle herd; however, many assisted reproductive technologies alter the normal microenvironment of the maturing oocyte and negatively impact oocyte competence for early embryo development. For example, oocytes induced to ovulate from preovulatory follicles of lesser physiological maturity (decreased estradiol production and smaller diameter) have reduced blastocyst development, poorer embryo quality, and a hastened rate of embryo development compared with those ovulated from follicles of greater maturity. Our overarching hypothesis is that the intrafollicular milieu of physiologically mature preovulatory follicles provides the necessary microenvironment to metabolically program maturing oocytes for successful embryo development. Studies by our team have demonstrated that the follicular fluid metabolite milieu during in vivo oocyte maturation differs between preovulatory follicles of greater and lesser maturity and that such differences have direct effects on the maturing oocyte. Numerous follicular fluid metabolites involved in glucose and amino acid metabolism were more abundant in preovulatory follicles of greater versus lesser physiological maturity. Additionally, abundance of transcripts encoding glycolytic enzymes was higher in cumulus cells from follicles of greater maturity, and both ATP and levels of key transcripts in the mitochondrial respiratory chain were higher in oocytes collected from preovulatory follicles of greater versus lesser maturity. We supplemented in vitro maturing oocytes with follicular fluid from preovulatory follicles of greater or lesser maturity to determine causality of differing follicular fluid milieu on cumulus-oocyte metabolism and oocyte competence for early embryo development. Follicle maturity status had robust effects on cumulus-oocyte complex consumption or production of key metabolites in glucose, purine, and amino acid metabolism pathways during oocyte maturation. We also observed hastened development rate in embryos arising from in vitro matured oocytes supplemented with lesser maturity follicular fluid, mirroring past in vivo findings by others. Furthermore, RNA-sequencing of resulting blastocysts of identical stage and quality suggested more efficient metabolism and Wnt/β-catenin signaling in blastocysts derived from oocytes matured in preovulatory follicular fluid from greater maturity follicles. In contrast, transcriptome profiles of blastocysts from oocytes matured in preovulatory follicular fluid from lesser maturity follicles indicated oxidative stress and dysregulated cell division. These recent findings by our lab indicate that impacts of follicle maturity and the resulting follicular fluid microenvironment on the maturing oocyte withstand throughout early embryo development and hold promising roles to improve reproductive efficiency in cattle.

Explanatory models and animal health-seeking behavior for East Coast fever in rural Kenya: an ethnographic study.

Explanatory models of disease focus on individuals' and groups' understandings of diseases, revealing a disconnect between livestock keepers and animal health providers. Animal health providers rely on models grounded in their veterinary training and experience. At the same time, livestock keepers may construct models based on traditional knowledge and their lived experience with East Coast fever in their cattle herds. To better understand East Coast fever and develop more efficient management strategies, this ethnographic study used the explanatory models' framework to provide a structured way for comprehending and contrasting different beliefs and understandings of East Coast fever as perceived by the livestock keepers across the different livestock production systems. Multiple data collection methods were employed, including unstructured observations, 30 in-depth interviews (IDIs), 18 focus group discussions (FGDs), and 25 key informant interviews (KIIs). Adult cattle, calves and sheep were perceived as susceptible to East Coast fever. However, there were varying perceptions of livestock susceptible to East Coast fever in the different livestock production systems. East Coast fever was attributed to multiple factors, including ticks, tsetse flies, mosquitos, birds, stagnant, dirty, or contaminated water, and livestock-wildlife interactions. However, some aspects were specific to the production system. Livestock keepers classified diseases based on observable signs, grouping diseases with similar signs under the same classification. Moreover, livestock keepers described different forms of East Coast fever ranging from treatable to fatal, which could be distinguished by the signs they presented. Self-treatment with drugs from the local agro-vet shops was the initial course of action during suspected cases of East Coast fever. Animal health practitioners were the last resort if self-treatment did not produce the desired outcome. Livestock keepers perceived avoidance of stagnant or contaminated water, tick control, and fencing as effective control measures for East Coast fever in their livestock herd. Very few livestock keepers were aware of an East Coast fever vaccine. Mechanistic explanations hold little significance in controlling East Coast fever. Instead, understanding and addressing livestock keepers' beliefs regarding ECF is crucial for promoting behaviors that support interventions across different livestock production systems.

The Prevalence and Molecular Characterization of Bovine Leukemia Virus among Dairy Cattle in Henan Province, China.

Enzootic bovine leukosis, a neoplastic disease caused by the bovine leukemia virus (BLV), was the primary cancer affecting cattle in China before 1985. Although its prevalence decreased significantly between 1986 and 2000, enzootic bovine leukosis has been re-emerging since 2000. This re-emergence has been largely overlooked, possibly due to the latent nature of BLV infection or the perceived lack of sufficient evidence. This study investigated the molecular epidemiology of BLV infections in dairy cattle in Henan province, Central China. Blood samples from 668 dairy cattle across nine farms were tested using nested polymerase chain reaction assays targeting the partial envelope (env) gene (gp51 fragment). Twenty-three samples tested positive (animal-level prevalence of 3.4%; 95% confidence interval: 2.2, 5.1). The full-length env gene sequences from these positive samples were obtained and phylogenetically analyzed, along with previously reported sequences from the GenBank database. The sequences from positive samples were clustered into four genotypes (1, 4, 6, and 7). The geographical annotation of the maximum clade credibility trees suggested that the two genotype 1 strains in Henan might have originated from Japan, while the genotype 7 strain is likely to have originated from Moldova. Subsequent Bayesian stochastic search variable selection analysis further indicated a strong geographical association between the Henan strains and Japan, as well as Moldova. The estimated substitution rate for the env gene ranged from 4.39 × 10-4 to 2.38 × 10-3 substitutions per site per year. Additionally, codons 291, 326, 385, and 480 were identified as positively selected sites, potentially associated with membrane fusion, epitope peptide vaccine design, and transmembrane signal transduction. These findings contribute to the broader understanding of BLV epidemiology in Chinese dairy cattle and highlight the need for measures to mitigate further BLV transmission within and between cattle herds in China.

The role of traditional ecological knowledge, given the transformation of pastoralism in Central and Eastern Mongolia.

Mongolian nomadic herders traditionally pass on ecological knowledge intergenerationally, mainly within families. However, little is known about how current societal transformation processes may impact the application and transfer of traditional ecological knowledge (TEK) amongst herders. Combining quantitative household survey data with qualitative interviews, we show that TEK is still widely applied amongst herders. Our data show that households living under conditions of greater societal transformation apply TEK more often in order to adapt to the situation than households under lower transformation pressure. High transformation pressure goes along with high human population and livestock density and thus competition for good pastureland. In addition, our results show that intragenerational knowledge transfer between families is gaining more importance nowadays. For Mongolia, we recommend facilitating access to and strengthening the exchange of TEK to prepare herders for the future due to the high level of uncertainty accompanying societal transformations.

Epidemiological Investigation of Animal Brucellosis in Domestic Ruminants in Greece from 2015 to 2022 and Genetic Characterization of Prevalent Strains.

Brucellosis is one of the most important zoonotic diseases in Greece, causing a significant burden on both human and animal vitality as well as economic loss. The present study was conducted from 2015 to 2022 on 711,415 serum samples by determining the seroepidemiology of Brucellosis among livestock in 24 geographical areas in Greece using the Rose Bengal Test (RBT) and the complement fixation test (CFT) and further performing genetic analysis of Brucella spp. by species-specific real-time PCR and MLVA Brucella analysis. A total of 3086 serum samples from goats, sheep, and cattle showed positive results using the RBT and CFT, and only strongly positive samples (n = 800) were preserved in the Βlood Bank of the Veterinary Laboratory of Brucellosis. From these, 212 sera samples were randomly selected for molecular and genetic analysis. The results indicated that the incidence rate of Brucellosis is higher in cattle herds in comparison with other animal species. Overall, 48 samples tested positive by real-time PCR, of which forty-seven of them were B. abortus and one was B. melitensis. Genetic analysis of two B. abortus samples revealed a common pattern, indicating two Bruce04, two Bruce18, four Bruce07, two Bruce09, three Bruce16, and four Bruce30 for both samples, which, interestingly, were not identical with the known genotypes in the public MLVA Brucella database. Our findings substantiate that animal Brucellosis remains a health issue in Greece, with a stable but apparent incidence rate, and further investigation is needed to fully characterize the newly identified Brucella strains in Greece.

Identification and phylogenetic analysis of bovine herpesvirus 4 isolated from aborted bovine foetuses in Türkiye.

Bovine herpesvirus 4 (BoHV-4) is responsible for reproductive disorders and abortions in cattle. The aim of this study was to investigate the potential role of BoHV-4 in abortions in dairy cows when the possible aetiological cause could not be determined in Türkiye. The study also provided the molecular characterization of BoHV-4 strains based on the gB gene. In this study, foetuses (n = 188) and serum (n = 50) were retrospectively used for PCR and indirect ELISA assays, respectively. In addition, foetuses with BoHV-4 were tested for the isolation of the BoHV-4 strain in MDBK cell culture. The BoHV-4 gB gene was detected in the brain, liver, lung, kidney, and spleen tissues of three foetuses out of 188 aborted foetuses. The BoHV-4 strain was isolated from the kidney of one foetus in MDBK cell culture. The three aborted foetuses were from different cows in the same herd in 2021. On this dairy farm, the BoHV-4 seroprevalence rate in cattle with a history of abortion was 96% (48/50). Phylogenetic analysis revealed that the detected strains belong to genotype II. The present study shows that the impact of BoHV-4 on abortions in cattle should not be ignored. It can therefore be informative to focus on BoHV-4 in routine laboratory diagnostics for abortions without a proven aetiology or in cattle herds that have previously been infected with BoHV-4.

Multivariate analysis of herd structure and genetic resource indicators in seedstock beef cattle herds.

Genetic, environmental, technological and financial resources are used differently in cattle herds that participate in the same breeding programme. The percentages of calves sired by sires within their own herd or from external herds vary across herds, as do the intensities of use of reproductive biotechnologies. These divergences may be related to differences in the indicators of genetic performance for economic traits. The aim of this study was to determine the factors related to herd structure and genetic resource utilization that exert the greatest influence on the genetic merit of seedstock herds within a Nellore breeding programme. The database comprised 21 factors, along with genomic-enhanced expected progeny differences (GE-EPDs) for growth, reproductive and carcass traits, as well as a selection index of animals from 128 herds. By combining principal component analysis and cluster analysis, we were able to group the herds. We identified statistically significant differences (p < 0.05) in the mean values of the factors, GE-EPDs and genetic trends among the groups of herds. Differences in the percentage of sires from external herds and in sire age between the groups of herds were the factors most associated with differences in mean GE-EPDs and genetic trends. Using young sires from other herds or lineages is an effective strategy in animal breeding. By enhancing genetic variability, this approach does not only improve the genetic quality of herds but also accelerates genetic progress in desired traits over time. Therefore, to ensure the success of this strategy, it is crucial that seedstock herds undergo a thorough selection process aimed at maximizing the genetic potential of future generations of beef cattle.

Body type and morphological indicators of the udder of red-motley cows in the Republic of Khakassia

Relevance. Creating a highly productive dairy herd of cattle, characterized by good health and a long service life, suitable for industrial milk production technology, is impossible without a systematic assessment of animals based on the exterior and morphofunctional properties of the udder.Methods. The research was carried out in 2023 in the breeding reproducer of “Tselinnoye” LLC, Shirinsky district. The exterior was studied in cows of the first, second, third and older lactation, as well as on the herd average by measuring body measurements and calculating body composition indices. The assessment of the morphological properties of the udder of the studied cows was carried out at 2–3 months of lactation, 1–1.5 hours before milking.Results. In terms of the size of the exterior measurements, red-motley cows correspond to the indicators of the desired type (on average for the herd, height at the withers is 136.15 cm, chest depth is 74.60 cm, chest width is 43.83 cm, chest girth is 198.45 cm, oblique length of the body — 159.57 cm, width at the hip joints — 53.50 cm, at the hip joints — 50.58 cm, oblique length of the butt — 53.55 cm, semi-circumference of the butt — 107.20 cm, metacarpus circumference — 19.54 cm), according to body indexes, they are characterized by a milk-meat body type (extension index — 117.25%, chest — 58.78%, hip-thoracic — 82.07%, tightness — 124.54%). The udder measurements are quite large (length — 44.48 cm, width — 34.42 cm, girth — 136.45 cm, depth of the anterior lobe — 31.72 cm, posterior — 31.30 cm), however, it is necessary to improve the uniformity of size and location nipples through selection for this trait.