Normal Cattle Research Articles

Impact of STAT5A-CNVs on growth traits in Chinese beef cattle breeds

CNVs, which are a type of structural variation, make a substantial impact on diverse characteristics in multiple species. Q-PCR and data association analysis were used for STAT5A gene copy in this study. This study aimed to investigate the copy number variation (CNV) of the STAT5A gene in seven Chinese cattle breeds, namely Qinchuan cattle, Xianan cattle, Yunling cattle, Ji’an cattle, Jiaxian Red cattle, Qaidam cattle, and Guyuan yellow cattle. Blood samples were collected for CNV typing, and the correlation between CNV type and growth traits was analyzed using SPSS 23.0 software and ANOVA. The findings revealed variations in the distribution of different copy number types among the different cattle breeds. Furthermore, association analysis demonstrated a positive impact of CNV in the STAT5A gene on cattle growth: in the JX, individuals with duplication types exhibited superior performance in terms of rump length (P < 0.05). Conversely, normal GY cattle demonstrated better body height and abdomen circumference (P < 0.05), while QD cattle exhibited a significant correlation between weight and body length with normal individuals (P < 0.05). Moreover, QC bovine duplication individuals outperformed other types, with copy number variation significantly associated with chest depth, chest width, and body length (P < 0.05). The results validate the correlation between copy number variation (CNV) of the STAT5A gene and growth characteristics in five different cattle breeds, providing a reliable benchmark for the purpose of cattle breeding.

Osteofluorosis in free ranging California sea lions (Zalophus californianus)

We report the first case series of osteofluorosis in free ranging marine mammals and documentation of baseline bone fluoride concentrations in this population; however, the exact source is not known. A stranded subadult male California sea lion, one subadult male carcass, and one partial carcass, presumably adult male, demonstrated osseous (bony) proliferations on various appendicular and axial bones. The most severe lesions were from the index case with symmetrical segmental circumferential periosteal new bone proliferation on the diaphysis of both femurs and humeri. This case, and the second case, also had significant segmental periosteal new bone proliferation on the mandibles as well as increased tooth wear with dull enamel. Total fluoride concentrations in various bones of the cases ranged from 3,700 to 9,700 ppm dw, with a mean of 5,431 ppm dw, approximately twice the concentration in adult cattle with osteofluorosis. Ribs from four control California sea lions of various ages and both sexes had an average total fluoride of 1,575 ppm dw, which is three times as high as the bone fluoride concentration of normal adult cattle, but four times lower than the mean rib fluoride concentrations in the cases. This is the first report of osteofluorosis in free ranging marine mammals and documentation of baseline bone fluoride concentrations in this population. The exact source of the excessive fluoride levels is not known as male California sea lions have a large range and varied diet.

EFFECT OF MASTITIS ON MILK COMPOSITION OF CROSS-BRED (HOLSTEIN FRIESIAN X CHOLISTANI) AND SAHIWAL CATTLE

The present study was designed to investigate the effect of mastitis on various components including fat percentage, protein, total solids, solid not fat, pH, specific gravity and lactose content in milk of cross-bred (Holstein Friesian × Cholistani) and Sahiwal cattle. A total of 376 milk samples (excluding blind and nonfunctional teats) from 100 cows (50 cross-bred and 50 sahiwal) were collected aseptically. Animals of different ages, parity and stages of lactation were selected under field condition. The diagnosis of subclinical mastitis was done on basis of Surf Field Mastitis Test. For bacterial examination of milk, the samples were grown in laboratory and various biochemical tests were performed. The results of the present study indicated that solid not fat (SNF) of mastitic sahiwal and cross-bred cattle and total solids percentage of normal and mastitic cattle were significantly reduced as the severity of mastitis increased in animals. The milk pH of normal and mastitic cattle including both sahiwal and cross-bred was significantly increased in severe cases of mastitis. The specific gravity of normal and mastitic milk samples showed that there was no significant difference in specific gravity as compared to normal. The protein percentage of normal and mastitic cattle including both sahiwal and cross-bred cattle indicated that protein concentration was significantly reduced in severe cases of mastitic animals. The findings of present study highlighted that mastitis cause major alterations in composition of milk leading to poor quality of the milk.

Bacterial Profiles of Brain in Downer Cattle with Unknown Etiology.

Downer cow can be caused by muscular paralysis, neurological damage, metabolic disorder, and/or the complication of microbial infection. However, downer cow with unknown etiology is issued because of the non-detection of its bacterial etiological agent. In this study, differences in the bacterial community in brain tissues between downer cattle with unknown etiology and healthy slaughtered cattle are investigated. Bacterial diversity and representative genera between downer and normal cattle were significantly different (p < 0.05). There are significant differences in representative genera of downer and normal cattle, especially the significance, fold change, and area under the receiver operating characteristic curve score (p < 0.05). Furthermore, the prediction of functional genes in brain microbiota between the downer and normal cattle revealed differences in the cluster of orthologous gene categories, such as lipid transport and metabolism, secondary metabolite biosynthesis, and signal transduction (p < 0.05). This study revealed a significant difference in microbiota between the downer and normal cattle. Thus, we demonstrate that representative genera from downer cattle through 16S rRNA gene amplicon sequencing and microbiota analysis have the potential as candidates for bacterial etiological agents for downer cow.

PSI-13 Effect of Targeted Metaphylaxis Using Blood Leukocyte Status on Health, Performance, and Economic Outcomes of Auction-Derived Feedlot Heifers

Abstract The study objective was to evaluate health, performance, and antimicrobial costs of heifers where targeted metaphylaxis was guided by a commercial blood leukocyte analyzer compared to a traditional metaphylaxis regimen. Using a randomized complete block design, heifers (n=1,271; initial body weight (BW) = 233.3±1.08 kg) were randomly allocated to treatment pens (n=20; 10 blocks). Treatments were: 1) cattle administered metaphylactic treatment with gamithromycin at arrival (META), and 2) cattle administered metaphylaxis with gamithromycin according to the blood leukocyte analyzer outcome (TARGETED). The blood leukocyte analyzer indicated immune status of individual animals according to the number and proportion of different leukocytes in the blood; red signified “abnormal” and green signified “normal” status. Only cattle with a red outcome were administered antimicrobial in the TARGETED treatment. Of all cattle enrolled in the study, 73% were deemed normal and 27% were deemed abnormal by the chute side blood analyzer. Treatment groups had an equal distribution of normal (META = 73% TARGETED = 74%) and abnormal (META = 28% TARGETED = 26%) cattle enrolled in the study. Cattle were fed a common starter ration for the duration of the 62-d study. Pen riders were blinded to treatment pen status. Data was analyzed using PROC MIXED and GLIMMIX in SAS. Final BW, ADG, and feed conversion were less for TARGETED (P≤0.02). However, the arrival processing antimicrobial cost (META = 11.77 and TARGETED = $3.27/heifer) and total antimicrobial cost (META = 17.77 and TARGETED = $9.12/heifer) was reduced (P&amp;lt; 0.01) for TARGETED. TARGETED had an arrival processing antimicrobial cost savings of $8.50/heifer and an overall drug input cost savings of $8.65/heifer. The BRD morbidity rate for normal status heifers was 18.85% and more than abnormal (26.49%; P&amp;lt; 0.01). Normal status heifers had a mortality rate of 3.17 vs. 5.80% for abnormal (P=0.03). In conclusion, drug costs were reduced but performance of TARGETED was also less.

Associations between cow-level parameters and heart rate variability as a marker of the physiological stress response in dairy cows.

To maintain and enhance cow productivity and welfare, it is important that we can accurately assess and understand how cows respond to the physiological demands of gestation and lactation. Several methods have been developed for assessing the physiological responses to stressors and for detecting distress in cattle. Heart rate (HR) variability (HRV) is a non-invasive measure of autonomic nervous system activity and consequently a component of the physiological response to stress. In cattle, HRV has been successfully used to measure autonomic responses to a variety of health conditions and management procedures. The objectives of this study were to determine whether, among commercial Holstein Friesian cows and across farms, relationships exist between cow-level factors, HR and HRV. HRV parameters were compared with production records for 170 randomly selected, Holstein-Friesian-cows on 3 commercial dairy farms. Production data included parity, days in milk (DIM), milk yield, somatic cell count (SCC), % butterfat and protein, body condition score (BCS) and genetic indices. Fixed-effect, multivariable linear regression models were constructed to examine the association between cow-level variables and HRV parameters. Statistically significant relationships were found between HR and farm, temperature and BCS, and between HRV parameters and farm, rectal temperature, BCS, DIM, and percentage butterfat. Given the significant association between farms and several of the indices measured, it is recommended that care must be taken in the interpretation of HRV studies that are conducted on animals from a single farm. The current study indicated that within clinically normal dairy cattle HRV differed with the percentage of butterfat and BCS. Based on the relationships reported previously between HRV and stress in dairy cattle these results suggest that stress may be increased early in lactation, in cows with BCS <2.75 that are producing a high percentage of butterfat milk. Future work could focus on the physiological mechanisms through which these factors and their interactions alter HRV and how such physiological stress may be managed within a commercial farm setting.

Molecular epidemiological investigation on Theileria in yellow cattle from Xiangxi Autonomous Prefecture of Hunan Province

To investigate the prevalence and genetic variation of Theileria in yellow cattle in Xiangxi Autonomous Prefecture of Hunan Province. A total of 184 blood specimens were collected from Fenghuang, Huanyuan and Baojing counties of Xiangxi Autonomous Prefecture during the period from August 2018 through August 2019, and were detect using PCR assay with the specific 18S ribosomal rRNA (18S rRNA) gene targeting Theileria. The gene sequences of positive specimens were aligned with the sequences recorded in GenBank, and a phylogenetic tree was created with Plasmodium ovale 18S rRNA as an outgroup. A total of 143 blood samples were positive for Theileria, with a mean detection rate of 77.7%. Theileria was prevalent in the blood samples from yellow cattle in all three counties, with detection rates of 85.0% in Fenghuang County, 88.3% in Huayuan County and 61.0% in Baojing County, respectively. There was no significant difference in the detection rate of Theileria between Xiangxi yellow cattle and normal yellow cattle (77.2% vs. 79.5%; χ2 = 0.08, P > 0.05), while the detection of Theileria was significantly lower in the housed yellow cattle than in free-range cattle (68.9% vs. 89.7%; χ2 = 22.36, P < 0.01). A total of 18 PCR positive samples were randomly selected for sequencing and analysis, and all samples showed more than 99.0% homology with T. luwenshuni isolates. Phylogenetic analysis showed that the 18 positive samples were clustered into the same branch with T. luwenshuni, but were far away from other isolates. The prevalence of Theileria is high in yellow cattle from Xiangxi Autonomous Prefecture of Hunan Province, and T. luwenshuni may be the dominant parasite species.

Haematology and biochemical profiles of endangered local cattle of Andaman and Nicobar Islands

Andaman and Nicobar Islands have two different genetic groups of cattle namely Andaman local cattle and Trinket cattle. Andaman local cattle are distributed in Andaman group of Islands and Campbell Bay of Nicobar group of Islands. Andaman local cattle are non-descriptive and represent an admixture of different Indian breeds that had been brought to these islands in different phases of inhabitation and rehabilitation of migrated people. It is believed that the Andaman local cattle have the inheritance from Red Sindhi, Sahiwal and Hariana. It is unique cattle, well adapted to special type of tropical humid island climatic and environmental condition. The present study was designed to standardise the normal reference haematological and biochemical range for different age groups of Andaman local cattle which were maintained in the South Andaman and North and Middle Andaman district, Andaman and Nicobar Islands, India. In this study, haematological parameters, biochemical indices and antioxidant and oxidative stress profiles were estimated in healthy, normal physiological Andaman local cattle for different age groups. The present study results clearly indicated that the values of haematological, biochemical and antioxidant profiles were under the normal physiological range. These results of this study may serve as the reference values in which alterations due to metabolic, nutrient deficiency, physiological and health status can be compared for diagnostic and therapeutic purposes for Andaman local cattle in Andaman and Nicobar Islands and its neighbouring countries or other parts of the country with similar environmental and climatic conditions.

Concentration of 2,3 bisphosphoglycerate in cattle affected with acute ruminal acidosis.

The main objective of the study conducted here was to estimate the concentration of 2,3‐Bisphosphoglycerate (2,3‐BPG), 1,3‐Bisphosphoglycerate (1,3‐BPG), bisphospho‐glycerate mutase (BPGM) and 3‐phosphoglycerate (3PG) in cattle clinically diagnosed with acute ruminal acidosis. A secondary objective was to examine the physical and chemical characteristics of the ruminal fluid in affected cattle. A total of 20 cattle clinically diagnosed with acute ruminal acidosis and eight clinically normal cattle were included in this study. The results showed that decrease of ruminal pH changed the ruminal fluid colour, odour and consistency, as well as decreased the sedimentation time, increased the methylene blue reduction time, and decreased ruminal microflora motility. The study indicated that the concentration of 2,3‐BPG, BPGM and BPGP decreased with the decrease of ruminal pH, while 3‐PG concentration was not affected with the decrease of ruminal pH. In conclusion, 2,3‐BPG could play a role in the pathogenesis of ruminal acidosis, and thus, the intravenous administration of sodium bicarbonate is important, particularly in severe cases, to correct any systemic acidosis that can decrease 2,3‐BPG concentration and results in tissue hypoxia.

Effects of various doses of lubabegron on calculated ammonia gas emissions, growth performance, and carcass characteristics of beef cattle during the last 56 days of the feeding period.

Lubabegron (LUB; Experior, Elanco, Greenfield, IN, USA) was approved by the U.S. Food and Drug Administration in 2018 and is indicated for the reduction of ammonia (NH3) gas emissions·kg−1 body weight (BW) and hot carcass weight (HCW) when fed to feedlot cattle during the final 14 to 91 d of the finishing period. LUB demonstrates antagonistic behavior at the β 1 and β 2 receptor subtypes and agonistic behavior at the β 3 receptor subtype in cattle and is classified by the Center for Veterinary Medicine as a “beta-adrenergic agonist/antagonist.” This report describes a randomized complete block study that evaluated LUB dose (0, 1.5, 3.5, and 5.5 mg·kg−1 dry matter) during the last 56 d of the feeding period on calculated NH3 gas emissions, live weight, carcass weight, and associated ratios in beef feedlot cattle. Carcass characteristics, mobility, and health were also evaluated. All cattle received monensin and tylosin throughout the study. Ammonia gas emissions were calculated using the equation developed by Brown et al. (Brown, M. S., N. A. Cole, S. Gruber, J. Kube, and J. S. Teeter. 2019. Modeling and prediction accuracy of ammonia gas emissions from feedlot cattle. App. Anim. Sci. 35:347–356). The reduction in calculated cumulative NH3 gas emissions with LUB ranged from 1.3% to 11.0% (85 to 708 g/hd). When NH3 gas emissions were expressed on a live weight (unshrunk) and carcass weight basis, calculated NH3 gas emissions decreased by 3.0% to 12.8% and 3.8% to 14.6%, respectively. Daily dry matter intake was 2.3% greater (Ptrt < 0.05) for steers that received LUB. Average daily gain was 13.7% greater (Ptrt < 0.05; 1.68 vs. 1.91 kg), while gain efficiency was 10.8% greater (Ptrt < 0.05; 0.167 vs. 0.185) for steers fed LUB. Animal mobility was scored in the pen approximately 1 wk prior to harvest, when cattle were loaded on trucks scheduled for harvest, and at antemortem inspection during lairage. No treatment differences (Ptrt ≥ 0.170) were observed at any time for the percent of cattle receiving mobility scores of 1 or 2 (normal or minor stiffness but moving with the normal cattle, respectively). Cattle mobility scored as a 1 or 2 equaled or exceeded 92% at all times. Final BW and HCW increased (Ptrt < 0.05) 11.6 to 15.7 kg and 11.3 to 17.1 kg, respectively, in cattle receiving LUB compared to cattle receiving monensin plus tylosin alone.

MEASUREMENT OF OVARIAN FOLLICLES AND VAGINAL TEMPERATURE OF BALI CATTLE THAT EXPERIENCE SILENT HEAT

This study aimed to improve Bali cattle's efficiency and productivity by measuring ovarian follicles and vaginal temperature in Bali cattle that experienced a silent heat using ten bali cattle with normal estrus and bali cattle that experience a silent heat. The research samples were divided into two groups: Bali cattle that showed normal estrus (grup I) and Bali cattle that experienced a silent heat (grup II), with each group consisted of 5 replications. Furthermore, all the cows were measured for vaginal measurements at the time of estrus and 24 hours after estrus. While ovarian follicles are measured at the time of estrus. The results showed that the average vaginal temperature of Bali cattle was 38.40 ± 0.130 C and 38.04 ± 0.130 C respectively for Bali estrus cattle and Bali cattle which experienced a silent heat and statistically showed a significant difference (P&lt;0.05). The Bali cattle follicles' average diameter is 10.60 ± 1.14 and 7.32 ± 0.37 mm, respectively, for the normal estrus and which experience a silent heat, and statistically show a significant difference (P&lt;0.05). From the results of the study, it can be concluded that the vaginal temperature of bali cattle with normal estrus is higher than that of bali cattle which experience a silent heat, and ovarian follicle diameter in normal estrus is greater than the diameter of the ovarian follicles of bali cattle that experience silent heat.

Mineral Composition of Serum from and Dermatophilus Infected Zebu Cattle Under Grazing Conditions in Nigeria

SERUM zinc (Zn), copper (Cu), calcium (Ca), magnesium (Mg) and potassium (K) were determined by atomic absorption spectrophotometry in Zebu cattle with dermatophilosis and in normal cattle under grazing conditions during the rainy season in Northern Nigeria. The mean serum Zn, Ca, Mg and K levels in cattle with dermatophilosis were found to be significantly lower than in normal cattle. The serum Zn, Ca and Mg values in Nigerian Zebu cattle during the rainy season appear to be lower than values found by most other workers for cattle found elsewhere. The converse is true for Cu and K. The differences in serum mineral values between Nigerian Zebu cattle and cattle in other countries may be due, among other reasons, to differences in the nutrient quality of the natural forages upon which grazing cattle subsist.

THE PREVALENCE OF MORAXELLA BOVIS IN CLINICALLY NORMAL CATILE EYES: ITS SIGNIFICANCE TO INFECTIOUS BOVINE KERATO-CONJUNCTIVITIS

In a study to determine the prevalence of Moraxella bovis in clinically normal cattles eyes in the Maiduguri area of Nigeria, 35 adult cattle (70 eyes) and 25 calves (50 eyes) were sampled. Three each of the adult and young cattle making a total of 6 (5%) were positive for M.bovis (the aetiological agent of infections bovine Keratoconjunctivitis) out of the 120 eyes sampled. Branhamella catarrhalis, Branhamella mucosa and Escherichia coli were each isolated respectively, from 2 (1.6%) of the 120 samples. The other bacterial species isolated were Bacillus (5:4.2%), Corynebacterium (17; 14.2%), Streptococcus (9; 7.7%) and Staphylococcus (21/17.5%), could be regarded as commensals. The epidemiological implications of finding M. bovis in clinically normal cattle eyes are discussed.

Haematology of normal and trypanosome infected Muturu cattle in southeastern Nigeria

Blood parameters of 23 Muturu cattle in a herd were studied between April and August 1998 by monthly examination of their blood samples. Fourteen of a total of 110 blood samples analysed (5 samples were unsuitable for analysis) were infected with Trypanosoma vivax. Data from the trypanosome-infected blood were included to evaluate the role of trypanosome infection. The blood values of infected animals were except for the erythrocyte indices of MCH and MCHC indistinguishable from those of uninfected animals. There were variations due to age and physiological status (Open heifer, pregnant and lactating). Mean RBC and WBC count, MCV and monocyte count were lower in calves than older animals. Open heifers had higher mean RBC and monocyte count, and lower WBC count, MCV and MCH than pregnant and suckling cows.

Detection of the CD18 gene mutation as a marker of BLAD genetic disorder of Holstein-Friesian cattle in West Java

&lt;p class="MDPI17abstract"&gt;&lt;strong&gt;Objective: &lt;/strong&gt;Bovine Leukocyte Adhesion Deficiency (BLAD) is a genetic disorder in Holstein-Friesian (HF) cattle that have a significant economic impact on dairy cattle breeding. Mutation c.383A&amp;gt;G in Cluster of Differentiation Molecule 18 (CD18) gene was known as related to BLAD. This study aimed to detect the CD18 gene mutation that causes BLAD of HF cattle in the West Java Province.&lt;/p&gt;&lt;p class="MDPI17abstract"&gt;&lt;strong&gt;Methods: &lt;/strong&gt;The genomic DNA was extracted from 88 blood samples of HF cattle from Cibungbulang-Bogor (n=34), Ciampea-Bogor (n=31), and Sukabumi (n=23) by the GB300 DNA extraction kit, Geneaid&lt;sup&gt;TM&lt;/sup&gt;. The CD18 gene mutation was detected by PCR-RFLP analysis using the &lt;em&gt;Taq&lt;/em&gt;I restriction endonuclease.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;p class="MDPI17abstract"&gt;&lt;strong&gt;Results: &lt;/strong&gt;All samples in this study produced two fragments DNA, i.e., 359 bp and 260 bp with the monomorphic homozygote genotype (BB). HF cattle with BB genotype indicated as normal cattle and did not carry BLAD.&lt;strong&gt;&lt;/strong&gt;&lt;/p&gt;&lt;strong&gt;Conclusions: &lt;/strong&gt;All samples in the three populations of West Java were free of BLAD genetic disorder. Identification of BLAD on HF cattle in other places, including bulls in the Center of Semen Production in Indonesia was needed to prevent this genetic disorder.

Urine protein-to-creatinine ratio in cattle with subclinical renal disease.

Urinalysis is not routinely used in bovine medicine, and there is no evidence as to whether urine protein-to-creatinine ratio (UPC) could be used for the diagnosis of renal diseases in cattle. The goal of the study was to determine alterations in UPCs observed with different subclinical renal diseases in clinically healthy cattle and to investigate whether UPC can efficiently differentiate cattle with and without subclinical renal pathology. Kidney and urine samples from 57 clinically healthy adult dairy (44) and beef (13) cattle were collected after slaughter. Urinary protein and creatinine concentrations were measured in an automatic analyzer, and urinary-specific gravity (USG) was measured using a temperature compensated refractometer. Kidney samples underwent histopathologic examination, and the cattle were classified as NL (no renal lesion) and L (lesions detected even in one kidney). Based on USG, the cattle were divided into the Normal USG (≥1.020) and Low USG (<1.020) groups. The cattle with either histopathologic lesions or low specific gravities were considered to have renal disease. Renal lesions were detected in 37 cattle. UPC values were significantly affected (P<.05) by USG values, and not by the type of lesion detected, breed, or age, and their interactions (P>.05). The analysis revealed that a UPC of ≥0.19 provided an optimal cut-off point for the differentiation between normal animals and those with renal disease with 66.0% sensitivity and 90% specificity. The UPC calculation is a useful tool for the differentiation of normal cattle and those with renal disease. A UPC of less than 0.19 is associated with the absence of renal damage, whereas higher values raise suspicion for renal disease.

The Number and Types of Bacteria in the Bali Cattle’s Vagina during Estrus and Pregnant

Bali cattle have very good potential for meat and calf supply, because they have good adaptability with good quality reproductive properties. However, good reproductive nature is threatened by diseases caused by bacteria. This study aims to determine the number and types of bacteria in the vagina of Bali cattle that are estrus and pregnant. Sample using vaginal swabs from 30 cows. The sample consisted of 10 swabs from non-estrus and not pregnant (control / normal) cattle, 10 swabs from estrus cows, and 10 swabs from pregnant cows. After the swab is carried out using a cotton bud, the results of the swab are stored in Stuart transport media. Samples planted in blood media to be identified and the number of colonies counted, then followed by Gram staining and biochemical tests then the results were presented descriptively. The result is the highest number of estrous cow colonies (1034 colonies), compared to non-estrous and non-pregnant cows (407 colonies) and pregnant (376 colonies). This type of bacteria is dominated by Klebsiella sp. (42.85%), Eschericia coli (28.7%), Streptococcus sp. (14.28%) and Bacillus sp. (14.28%).

Mapping of CD4+ T-cell epitopes in bovine leukemia virus from five cattle with differential susceptibilities to bovine leukemia virus disease progression

BackgroundBovine leukemia virus (BLV), which is closely related to human T-cell leukemia virus, is the etiological agent of enzootic bovine leukosis, a disease characterized by a highly prolonged course involving persistent lymphocytosis and B-cell lymphoma. The bovine major histocompatibility complex class II region plays a key role in the subclinical progression of BLV infection. In this study, we aimed to evaluate the roles of CD4+ T-cell epitopes in disease progression in cattle.MethodsWe examined five Japanese Black cattle, including three disease-susceptible animals, one disease-resistant animal, and one normal animal, classified according to genotyping of bovine leukocyte antigen (BoLA)-DRB3 and BoLA-DQA1 alleles using polymerase chain reaction sequence-based typing methods. All cattle were inoculated with BLV-infected blood collected from BLV experimentally infected cattle and then subjected to CD4+ T-cell epitope mapping by cell proliferation assays.ResultsFive Japanese Black cattle were successfully infected with BLV, and CD4+ T-cell epitope mapping was then conducted. Disease-resistant and normal cattle showed low and moderate proviral loads and harbored six or five types of CD4+ T-cell epitopes, respectively. In contrast, the one of three disease-susceptible cattle with the highest proviral load did not harbor CD4+ T-cell epitopes, and two of three other cattle with high proviral loads each had only one epitope. Thus, the CD4+ T-cell epitope repertoire was less frequent in disease-susceptible cattle than in other cattle.ConclusionAlthough only a few cattle were included in this study, our results showed that CD4+ T-cell epitopes may be associated with BoLA-DRB3-DQA1 haplotypes, which conferred differential susceptibilities to BLV proviral loads. These CD4+ T-cell epitopes could be useful for the design of anti-BLV vaccines targeting disease-susceptible Japanese Black cattle. Further studies of CD4+ T-cell epitopes in other breeds and using larger numbers of cattle with differential susceptibilities are required to confirm these findings.

Aging of bovine spinal cord: an alteration of myelinated nerve fibers in the white matter

To gain more knowledge of age-related changes in the spinal cord of the bovine species, the structure of 15 clinically normal aged cattle (Holstein-Friesian cows 8–13 years of age) was histopathologically examined. In 12 (80%) of the 15 animals, the common histopathological features identified were alteration of a small number of myelinated nerve fibers in the white matter, with less than 4 nerve fibers affected per cross-sectional area of the spinal cord. Alteration of nerve fibers was characterized by dilation of myelin sheaths with loss of axons or macrophage infiltration, resembling features of Wallerian axonal degeneration. The occurrence of this nerve fiber alteration had a predilection for the lateral and ventral white matter funiculi. In eight cattle, so-called axonal spheroids were rarely present in the white matter. There was little evidence of glial reaction against nerve fiber alteration. Gray horn neurons were unremarkable. Lipofuscin granules were recognized in neurons, glial cells, and neuropil of the medulla oblongata examined in six cows. The changes observed in the spinal cord white matter of the present cows were similar to those described previously in aged human beings and domestic and laboratory animals, and thus were likely to have been a phenomenon which was closely related to aging. The strict clinical significance of the histopathological changes in the spinal cord white matter remains undetermined.

Vertebral heart size in healthy Australian cattle dog.

The vertebral heart score or size (VHS) measurement is routinely used to provide a more objective measurement of cardiomegaly in dogs. However, breed or body conformation can influence the VHS.To assess the specific VHS for the Australian Cattle Dog, left-to-right lateral, right-to-left lateral, dorsoventral and ventrodorsal thoracic radiographs from 20 individuals free from cardiac and pulmonary disease were obtained. The mean VHS was significantly higher in Australian Cattle Dog (10.5±0.4 vertebrae), when compared with the average VHS for 100 normal dogs of different breeds that had been initially published (9.7±0.5 vertebrae). This emphasizes the importance of breed-specific VHS ranges. In our study group of normal Australian Cattle Dogs, the mean VHS was 10.5±0.5 vertebrae (mean ±SD) on right lateral and 10.3±0.5 vertebrae on left lateral radiographs. The VHS on right lateral views was significantly larger than on left lateral views. The VHS was 10.5±0.6 vertebrae on dorsoventral and 11.1±0.6 vertebrae on ventrodorsal radiographs. The VHS on ventrodorsal views was significantly larger than on dorsoventral views.