Bovine Calves Research Articles

20 Young Scholar Talk PHD: Implications of Histone Toxicity and Complement System Activity in Sheep and Cattle During Immunomodulatory States Including Respiratory Disease and Pregnancy

Abstract The immunostimulatory and toxic effects of extracellular histones have been demonstrated in humans and rodents suffering from acute respiratory distress syndrome and acute lung injury. Accumulating evidence suggests intricate interactions between extracellular histones and immune complement system proteins occur as a regulatory mechanism. However, limited information is available on the interactions of complement system activity and histone toxicity during immunomodulatory events in livestock. Therefore, our current research is aimed at investigating the contributions of histone toxicity and complement system activity in relation to respiratory disease and pregnancy in wild and domestic sheep and cattle. In an initial study, feedlot heifers were evaluated for protective capacity against extracellular histones and complement activity related to subsequent disease outcomes. At feedlot arrival, serum samples were collected from 118 heifer calves (BW 229 ± 2.4 kg) and subjected to a histone toxicity assay and a 50% hemolytic complement activity assay. Heifers were retrospectively assigned as either never receiving treatment with antibiotics for bovine respiratory disease (NT; n = 80) or calves that died from bovine respiratory disease within 1 wk of entering the feedlot (DA; n = 9). Serum from DA animals was less (P < 0.001) protective against histone toxicity compared to NT heifers. Likewise, complement activity of DA animals was reduced (P < 0.05) compared to NT animals. These results suggest cattle predisposed to severe cases of respiratory disease have impaired complement system activity presumably leading to reduced protection against histone toxicity. In a second study, wild Alaskan Dall sheep (Ovis dalli dalli) and domestic sheep (Ovis aries) were evaluated for susceptibility to histone toxicity. Serum was collected from Debouillet sheep (n = 150) with no clinical signs of illness and serum of wild Alaskan Dall sheep (n = 135) was collected from live capture and release animals. Dall sheep serum was less (P < 0.05) protective against histone toxicity compared to Debouillet sheep. Low protection against histone toxicity may be related to higher reported disease states for wild sheep. Furthermore, recognizing that disease modulates immune function, it is also recognized pregnancy relies on immune system activation. Therefore, pregnant sheep serum was evaluated to determine the effect of histone toxicity and complement system activity. Serum was collected from Debouillet ewes (n = 8) and analyzed for histone toxicity protectiveness and complement activity. Serum was collected from ewes prior to breeding (d -0) and at d 1 and 17 of the estrous cycle. Serum protective capacity against histones and complement activity was not significantly different on d -0 compared to d 1 and d 17. Collectively, these data implicate the toxic effect of extracellular histones and complement system activity during respiratory disease states with less obvious observations during pregnancy.

Chromosome-encoded IpaH ubiquitin ligases indicate non-human enteroinvasive Escherichia

Until recently, Shigella and enteroinvasive Escherichia coli were thought to be primate-restricted pathogens. The base of their pathogenicity is the type 3 secretion system (T3SS) encoded by the pINV virulence plasmid, which facilitates host cell invasion and subsequent proliferation. A large family of T3SS effectors, E3 ubiquitin-ligases encoded by the ipaH genes, have a key role in the Shigella pathogenicity through the modulation of cellular ubiquitination that degrades host proteins. However, recent genomic studies identified ipaH genes in the genomes of Escherichia marmotae, a potential marmot pathogen, and an E. coli extracted from fecal samples of bovine calves, suggesting that non-human hosts may also be infected by these strains, potentially pathogenic to humans. We performed a comparative genomic study of the functional repertoires in the ipaH gene family in Shigella and enteroinvasive Escherichia from human and predicted non-human hosts. We found that fewer than half of Shigella genomes had a complete set of ipaH genes, with frequent gene losses and duplications that were not consistent with the species tree and nomenclature. Non-human host IpaH proteins had a diverse set of substrate-binding domains and, in contrast to the Shigella proteins, two variants of the NEL C-terminal domain. Inconsistencies between strains phylogeny and composition of effectors indicate horizontal gene transfer between E. coli adapted to different hosts. These results provide a framework for understanding of ipaH-mediated host-pathogens interactions and suggest a need for a genomic study of fecal samples from diseased animals.

Transmission Dynamics of Cryptosporidium in Calves and Children from Southwestern Ethiopia

Introduction: Cryptosporidium is a protozoan parasite that can affect both humans and animals. The present study aimed to determine the prevalence and risk factors of cryptosporidiosis in bovine calves and children in Jimma, southwestern Ethiopia. This cross-sectional study was conducted from December 2019 to July 2020 to assess the prevalence and risk factors of the infection among calves younger than 1 year and children younger than 5 years.
 Materials and methods: Fecal samples were collected from 384 calves and 147 children and examined by the Modified Ziehl-Neelson staining method.
 Results: The overall prevalence was 8.1% in calves and 7.5% in children. The multivariable logistic regression analysis showed that the risk of Cryptosporidiosis was significantly higher in younger calves < 3 months followed by river water users and calves kept in dirty pens. Moreover, the analysis of children data indicated that the risk of Cryptosporidiosis was significantly higher in children >1 year, followed by children settled around the rural area, children whose families had a poor habit of handwashing after attending cattle, children whose their family had a high level of contact with calves, and children who were drinking river water.
 Conclusion: The present study revealed that the high prevalence of cryptosporidiosis may be due to poor hygienic status, unclean sources of water, attending farms, and contact with calves or their feces. Generally, poor personal and dairy farm hygiene and drinking river water source were the factors contributing to the disease.

Genetic diversity, frequency and concurrent infections of picobirnaviruses in diarrhoeic calves in Turkey.

Calf diarrhoea is one of the major problems in cattle farming with high morbidity and mortality in herds. Two enteric viruses, bovine rotavirus (BRV) and bovine coronavirus (BCoV), are the leading cause of gastroenteritis in young calves, whereas picobirnaviruses (PBVs) are often associated with diarrhoea. In the present study, the faecal specimens of 127 diarrhoeic bovines (less than 1-month-old) were employed to investigate the infection frequencies of these three pathogens. Results indicated that frequencies of BRV and BCoV in diarrhoeic calves were 38.58% and 29.92%, respectively. The 7.08% of bovine calf samples (9 out of 127) were found to be positive for PBV genogroup I. Sequence analysis further revealed the high genetic heterogeneity within representative PBV sequences. Additionally, both PBV-BCoV (n = 2) and BCoV-BRV-PBV (n = 1) co-infections were detected in bovine calves for the first time. Consequently, our findings pointed out the highly divergent nature of PBVs without regard to exact host or territory and the occasional co-existence with other enteric agents.

Study on tapeworm infection in bovine calves of Bardibas Municipality, Mahottari

A study on Tapeworm infection in Bovine Calves of Bardibas Municipality, Mahottari district of Nepal was conducted during March – April 2021. A total of 100 fecal samples were collected from Ward No. 1,4 and 7 and examined in the laboratory as described by Soulsby, (1976). The laboratory examination was conducted at the Parasitology Laboratory of Himalayan College of Agricultural Sciences and Technology (HICAST). The overall prevalence of Moniezia spp. in bovine calves was found to be 5% (5/100). Based on the result, the prevalence of Moniezia spp. infestation in buffalo calves was found to be higher 8% (4/50) in comparison to Moniezia infestation in cattle calves 2% (1/50). The prevalence of Moniezia spp. according to the age group was found to be higher 5.56% (4/72) in the age group of 1-3 months compared to the age group of 0-1 month 3.57% (1/28). According to the location, the prevalence of Moniezia spp. the infestation was higher in Kisannagar at 6.38 % (3/47) in comparison with the Ratmata 4% (1/25) and Sunaulo Basti 3.57% (1/28).

Validating a bovine model for lung ultrasound of bronchiolitis.

PurposeBronchiolitis is a very common acute lung disease in infants caused commonly by respiratory syncytial virus (RSV). Point-of-care lung ultrasound is increasingly used in clinical care but proof that ultrasound reflects histological disease is lacking. Bovine calves are a good model for RSV bronchiolitis. We answered the following two questions: (1) does point-of-care lung ultrasound reflect lung pathology at the histological level in a bovine calf model of bronchiolitis? and (2) are point-of-care lung ultrasound images in human infants similar to those obtained in calves?MethodsWe experimentally infected 24 five to six-week-old bovine calves with RSV and compared six window lung ultrasound with lung histology10 days after inoculation. The calves were treated with antivirals and antipyretics leading to variable severity of illness. We used canonical discriminant analysis to determine if abnormal lung ultrasound findings reflected different histological findings. We compared the ultrasounds obtained from the calves with ultrasounds obtained from 10 human infants who were diagnosed clinically with bronchiolitis.ResultsCanonical discriminant analysis generally demonstrated good class separation based on the maximal severity of ultrasound finding in each acoustic window. Lung ultrasound performed poorly at detecting bronchopneumonia. Bovine ultrasounds looked similar to human infant lung ultrasounds.ConclusionPoint-of-care lung ultrasound abnormalities reflect lung pathology at the histological level in a bovine calf model of bronchiolitis. Point-of-care lung ultrasound images in human infants are similar to those obtained in calves.

Modified technique for estimating total body water in live animals using Antipyrine substance for measuring thermal tolerances

Estimating the total body water (TBW) in the live animals using the Antipyrine (ANP) substance as a modified technique was the first objective of this research. TBW was estimated in vivo in ten native bovine calves using the conventional method (extrapolation technique) and also by the suggested modified method (equilibration technique). The averages of TBW in native bovine calves were 136.5±16 and 133.1±16 liters by convention and modified technique, respectively, without significant differences between the two techniques. The accuracy of the modified technique was 97.5 % as compared with the convention method and at the same time, the new method is an easy, simple, accurate and quick technique and more reliable. Estimation of heat adaptability of animals to heat stress conditions was the second objective of this research. Animals when exposed to high ambient temperature the TBW increases and consequently TBS (Live body weight-TBW) decreases with different percentages according to the animal response to stressful conditions. TBW or TBS values were estimated before and after heat stress exposure and the percentage change in TBW or TBS in the animal due to heat stress may be used for evaluating the animal's adaptability to heat stress. The percentage increase in TBW or the percentage decrease in TBS due to heat stress conditions may be used as an index for heat-tolerance coefficient (HTC). The most heat- tolerance animals are those with the highest HTC values.

Comparative evaluation of various diagnostic techniques for detection of Cryptosporidium infection from the faecal samples of diarrhoeic bovine calves.

Cryptosporidium, an opportunistic, zoonotic, apicomplexan parasite, is one of the most common causes of diarrhea in neonatal bovine calves around the globe. Bovine calves act as a major source of infection by excreting huge numbers of highly resistant oocysts in faeces, which can survive for a long time in extreme environmental conditions. As low as ten oocysts can cause disease and mortality, leading to the requirement of an early and accurate diagnosis for proper and favorable prognosis, management, and control. The current study was conducted with the objective to evaluate various diagnostic techniques (acid fast staining, negative staining, fluorescent, ELISA, PCR, nested PCR, and qPCR) for the detection of Cryptosporidium in the faecal samples of diarrheic bovine calves. Two hundred diarrheic faecal samples from bovine calves were collected and subjected to these techniques for Cryptosporidium diagnosis. Results of these were evaluated for diagnostic comparison. Out of 200 faecal samples evaluated, 24% (48/200) were detected positive for Cryptosporidium using a combination of two techniques as gold standard criteria. Cohen's kappa value indicated moderate to almost perfect agreement (0.616 to 0.986) among all the techniques used in the present study. Leishman staining showed the lowest sensitivity (54.17%), while nested PCR and qPCR showed the highest sensitivity (97.92%). Diagnostic specificity of all these tests ranged from 98.68 to 100%. Auramine stain was used for the first time in the bovine calves in India for the detection and diagnostic comparison of Cryptosporidium. It showed strong agreement with the molecular as well as classical diagnostic techniques, and can be used for primary screening for better diagnosis.

Farm and animal-level risk factors associated with rectal prolapse in bovine and buffalo calves in Egypt with special reference to the optimal treatment strategy.

Background:Rectal prolapse (RP) is a serious illness of the rectum and small intestine causing serious health problems in domestic animals. However, there is paucity in the estimation of the risk factors associated with this problem in calves.Aim:In the present study, we investigated the prevalence and risk factors associated with the rectal prolapse in both bovine and buffalo calves in Egypt, highlighting the most appropriate treatment strategy.Methods:Forty-two calves (23 bovine and 19 buffalo) suffering from varying degrees of rectal prolapse were used. From the owners’ anamnesis, the farm- and animal-level risk factors associated with each animal were collected. Fisher’s exact tests were used to determine the distribution of frequencies in the different rectal prolapse grades. Descriptive statistics were calculated in the form of mean ± standard deviation (SD) using one-way analysis of variance. Crosstabs were used to determine Spearman’s correlation between variables. According to the disease severity, the appropriate treatment strategy was accomplished either by medicinal or surgical interferences.Results:The final logistic regression form demonstrated that the statistical test, Hosmer and Lemeshow’s goodness of fit, indicates a significant result (χ2 = 8.91). Body score was the potential risk factor for the occurrence of RP in calves. Medicinal management along with dietary modification was sufficient to treat 70% of grade I in a successful manner, while 33.3% (grade I and grade II) were effectively treated surgically with reduction and application of purse-string sutures.Conclusion:The current study advocates the valid role of resection of rectal mucosa combined with manual reduction and retention in treating calves suffering from grade II rectal prolapse. The final multivariate logistic regression model indicates that the calf’s body score is a potential risk factor for the occurrence of RP.

Histopathological alterations associated with immunolocalization of Clostridium perfringens and Salmonella spp in neonatal bovine calves died of diarrhoea

Histopathological alterations associated with immunolocalization of Clostridium perfringens and Salmonella spp in neonatal bovine calves died of diarrhoea

Clinical, hematological and some biochemical alterations during diarrhea in Friesian calves naturally infected with E. coli and Salmonella

BackgroundThis study aimed to assess the clinical and hemato-biochemical changes associated with diarrhea in E. coli and Salmonella pathogens in Friesian bovine calves less than one month old as well as to examine the relationship between Vit D3 and cardiac biomarkers.ResultsThe study was carried out on 43 Friesian calves from a private farm in Ash Sharqia Governorate, 33 diarrheic calves aged 1–14 days with an average body weight 43.7 ± 1.2 kg, and 10 apparently healthy calves were kept as a control group to investigate the clinical and hemato-biochemical profiles. E. coli and Salmonella pathogens were isolated from the diarrheic calves where 76% were E. coli and 24% were Salmonella. Diarrheic calves showed signs of anorexia, weakness, dullness, staggering gait, pale mucous membranes with sunken eyes and dehydration. Analysis of clinical and hemato-biochemical profile of the diarrheic calves revealed significant increase in body temperature, respiratory rate, heart rate, white blood cells, neutrophils, serum potassium, urea, creatinine, ALT, AST, cardiac NT-proBNP and cardiac troponin I with significant decrease in hemoglobin, packed cell volume, erythrocytes, serum Vit D3, sodium, glucose, total protein and albumin concentrations.ConclusionsIt could be concluded that bacterial diarrhea has a severe negative impact on the clinical and hemato-biochemical profile of the neonatal calves with diarrhea. Serum cardiac biomarkers such as cardiac troponin I (cTn-I) and NT-proBNP were significantly higher in neonatal calves with diarrhea, and there is an important relationship between cardiac biomarkers and vitamin D levels.

Etiology and risk factors for bovine respiratory disease in pre-weaned calves on California dairies and calf ranches

Our study objective was to estimate the magnitude of association of BRD risk factors including failure of passive immunity transfer, sex, age, and the detection of suspected BRD etiological pathogens in pre-weaned dairy calves in California. A conditional logistic regression model and a mixed-effects logistic regression model were used to estimate the association of these potential risk factors with BRD from a matched and nested case-control studies, respectively. For each exposure covariate, the odds ratio (OR) is the ratio of odds of an exposure in a BRD calf (case) to that in a non-BRD calf (control).In the matched case-control study, an interaction term between failure of transfer of passive immunity and sex of calf showed that female calves were more negatively impacted by failure of transfer of passive immunity compared to male calves. The odds ratios comparing failure of transfer of passive immunity in BRD score positive calves versus controls for male calves was 1.34 (95 % CI: 0.87, 2.06) and was 2.47 (95 % CI: 1.54, 3.96) for female calves. The model odds ratios varied from 1.74 (95 % CI: 1.26, 2.42) for Mycoplasma spp. to 9.18 (95 % CI: 2.60, 32.40) for Histophilus somni, with Mannheimia haemolytica and Pasteurella multocida having an OR of 6.64 (95 % CI: 4.39, 10.03) and 6.53 (95 % CI: 4.44, 9.59), respectively. For bovine respiratory syncytial virus positive calves, the OR was 4.60 (95 % CI: 3.04, 6.97).Findings from the nested case-control study showed that based on thoracic ultrasonography findings consistent with BRD, the odds of a calf being 1 day older compared to a day younger were 1.01 (95 % CI: 1.00, 1.02) among BRD cases. For the bacterial and viral pathogens, the OR for Mycoplasma spp. and Pasteurella multocida were 1.85 (95 % CI: 1.24, 2.75) and 1.86 (95 % CI: 1.28, 2.71), respectively. The OR values for these pathogens were similar when both thoracic auscultation and ultrasound findings were used to detect cases of BRD. Based on positive scores for BRD using the California BRD scoring system, the OR for facility type, calf ranch versus dairy farm, was 3.17 (95 % CI: 1.43, 7.01), Mannheimia haemolytica was 3.50 (95 % CI: 2.00, 6.11), Pasteurella multocida was 1.78 (95 % CI: 1.21, 2.60), and bovine coronavirus was 2.61 (95 % CI: 1.85, 3.70).Results from both study designs showed the difference in relative contributions of age, sex, immune status, and pathogens in BRD occurrence between cases and controls in pre-weaned dairy calves.

A Brief Review of Ideal Bio-Indicators, Bio-Markers and Determinants of Endemic of Fluoride and Fluorosis

Fluorosis in man and animals is the resultant of chronic exposure of Fluoride (F) for prolonged period through F contaminated drinking water and foods and industrial F pollution. However, fluoridated water and industrial F emissions are the major sources of F exposure for humans and domestic animals. Chronic F exposure not only deteriorate the health of human beings and animals but also causes diverse adverse toxic effects on hard (teeth and bones) and soft (organs) tissues. Various F induced pathological changes in teeth and bones are known as dental and skeletal fluorosis, respectively. However, skeletal fluorosis is more dangerous and highly significant since it diminishes the mobility at a very early age and develops crippling or lameness bone deformity. Thousands of people and domestic animals are suffering with fluorosis worldwide. Dental fluorosis is rampant and the commonest form of chronic F toxicosis and appears in subjects of almost all age groups. However, children and bovine calves are relatively more sensitive and highly susceptible to F toxicosis and revealed the earliest clinical sign of chronic F poisoning in the form of dental fluorosis. Hence, these are ideal bio-indicators for chronic F intoxication or fluorosis. Nevertheless, the magnitude or severity of fluorosis is much more depending on the density and rate of bio-accumulation of F. Biological samples, milk, urine, blood serum, teeth, nails, etc. are better bio-markers for F intoxication. However, urine F concentration is the best bio-marker for endemic of F and fluorosis. In this communication, ideal bio-indicators and bio-markers for endemic of F and fluorosis and diverse potential determinants influencing the severity of F toxicity (fluorosis) are considered and briefly and critically reviewed. Findings of this review are useful in making and implementation of health policy and the commencement of mitigation and control of fluorosis programme in F endemic areas where it is problematic for human and animal health.

Cross-sectional study and genotyping of rotavirus-A infections in ruminants in Kuwait

BackgroundGroup A rotaviruses (RVA) are zoonotic pathogens responsible for acute enteritis in human and neonatal ruminants. This research aimed to determine the prevalence of RVA in ruminants (cattle, sheep, and goats) and investigate the circulating RVA genotypes in these animals in Kuwait. We conducted a cross-sectional study to detect RVA in ruminants, using an immunochromatography test (IC), direct sandwich ELISA test, and real-time RT-PCR (RT-qPCR) assay using fecal samples.ResultsA total of 400 cattle, 334 sheep, and 222 goats were examined. The prevalence of RVA was 5.3, 1.2, and 2.3%, respectively, using IC. The ELISA test detected RVA from 4.3% of cattle, 0.9% of sheep, and 1.8% of goats. There was a significant association between the occurrence of diarrhea and the presence of RVA in bovine fecal samples (p-value = 0.0022), while no statistical association between diarrhea and the presence of RVA in fecal samples of sheep and goats was observed (p-value = 0.7250; p-value = 0.4499, respectively). Twenty-three of the IC-positive samples (17 from cattle, two from sheep, and four from goats) were tested using a RT-qPCR RVA detection assay targeting the NSP3 gene. The results showed that 21 of 23 IC-positive samples tested positive by RT-qPCR. Detection of RVA genotypes revealed that G10P[11] was the predominant strain in cattle (58.8%), followed by G8P[1] (11.7%). One sheep sample was genotyped as G8P[1]. In addition, G6P[1] and G6P[14] were detected in goat samples.ConclusionThe present study revealed that the IC was more sensitive in detecting RVA antigen in fecal samples than the ELISA test. A higher occurrence of RVA infection was observed in cattle than in sheep and goats. This study suggests that RVA might be a risk factor of diarrhea in bovine calves less than 2 weeks old. This research also demonstrates the circulation of RVA in sheep and goat populations in Kuwait. Finally, the G10P[11] RVA genotype was the most prevalent genotype identified from cattle samples.

Minimally Invasive Surgical Versus Ultrasound Guided Inguinal Tube Cystostomy for Management of Obstructive Urolithiasis in Cattle

Background: Tube cystostomy, though a popular technique to relieve obstructive urolithiasis in ruminants with advantages of lower recurrences, preservation of the reproductive function of the animal and restoration of full urethral patency in successful cases, is time consuming and invasive. Tube cystostomy performed under ultrasound guidance is hypothecated to be technically easier, safer and quicker. Methods: Twelve bovine intact male calves of 3-9 months age with obstructive urolithiasis were divided into two groups of six animals each. One group was subjected to surgical and another ultrasound guided minimally invasive tube cystostomy through the inguinal approach. In group A animals, after exposing the bladder throughthe grid incision, the catheter was placed in the bladder lumen, using teat tumor extractor fixed in the eye of the Foley’s catheter. In group B animals tube cystostomy under ultrasound guidance was performed through in the skin. Incision was closed as per routine. Techniques were evaluated on the basis of various parameters like, technical feasibility, use of anesthesia, use of suture material, time taken for surgery, haematobiochemical parameters, time taken for normal urination, survival rate and intra and postoperative complications. Result: Ultrasound guided minimally invasive inguinal tube cystostomy technique was not only technically easier to perform but also required lesser time, lesser suture material with quicker onset of normal urination Obstruction of catheter occurred in one animal of each group. Survival rate of 67% without any complication was recorded in both groups.

Immunological and molecular detection of rotavirus genotype in calves with gastroenteritis in Diyala-Iraq

Aim: To explore the prevalence of rotavirus infection along with the molecular detection and genotyping of group A rotavirus (RVA) among bovine calves up to 5 months old in Diyala province-Iraq. Methods: This is a cross sectional study conducted in Diyala province-Iraq during the period of 2019-2020. One hundred bovine calves with age range of 1-5 months were included in the study. All were suffering acute gastroenteritis. Serum anti-rotavirus IgM and IgG plus fecal rotavirus Ag were tested for using ELISA techniques. Stool samples positive for rotavirus Ag were submitted for reverse transcription PCR (RT-PCR) for G and P genes, followed by sequencing and genotyping thereafter. Statistical analysis was done using SPSS version 25 and P values ≤ 0.05 were considered significant. Results: The positivity rate of anti-rotavirus IgM was 80% (P = 0.0001), and that of anti-rotavirus IgG was 79% (P = 0.0001). The rotavirus stool antigen was detected in 68% of calves (P = 0.01). A total of 45 stool samples which were positive for rotavirus Ag were submitted for RT-PCR; 13 (28.9%) were positive and 32 (71.1%) were negative (P = 0.084). 10 PCR positive samples were used for sequencing and genotyping and indicated that all investigated strains belonged to G1P[8] genotype. Conclusion: The current strains analyzed belonged to the G1P[8] RVA genotypes, affirming that employment of VP7 gene polymorphism accurately yielded uniform phylogenetic distances amongst investigated rotavirus strains and that there were no noticeable assortment events between human and animal rotavirus strains in Diyala province.

Beef productivity of steers when feeding protein-vitamin-mineral additive and protein-vitamin-mineral concentrate

The purpose of the work was to study the influence of protein-vitamin-mineral additive and protein-vitamin-mineral concentrate on the growth, development and meat productivity of steers. Studies have been carried out on the rearing of steers when using the protein-vitamin-mineral additive based on extruded soybean with bentonite in the preweaning period and the protein-vitamin-mineral concentrate (with urea concentrate) when fattening steers. During the first research and production experiment in the calves of the 1st experimental group 30 % and in the bovine calves of the 2nd experimental group 40 % milk replacer have been replaced with a protein-mineral-vitamin additive. At the beginning of the experiment the calves of all groups had almost the same live weight. Starting from the age of 1,5 months the growth of the animals of the experimental groups began to prevail over the control group. Thus, the bull calves of the 1st experimental group at 2 months of age were larger than the control ones by 5,1 %, by the end of the experiment their superiority was 7,6 % (P < 0,01). The total gain in live weight of the bull calves of the 2nd experimental group was 9,4 % higher (P < 0,001) than in the control group. During the second research and production experiment on the use of protein-vitamin-mineral concentrate the difference in feeding was that the steers of the experimental group consumed complete feed, which included protein-vitamin-mineral concentrate (with urea concentrate) and bentonite. The gain in live weight of calves for 5 months of experiment in the control group was 136,7 kg, and in the experimental group it was 11,4 % more. The expenditures of feed per 1 kg of gain in EFU were by 10,1 % lower in the experimental group compared to the control group. The level of profitability of beef production in the control group was 16,1 %, and in the experimental group it was 26,5 %, which was more by 10,4 abs.%.

Presence of Human G Rotavirus Genotypes Amongst Bovine Calves and its Combination with P Genotypes

Background: Bovine Rotavirus is one of the most important viral etiological agent responsible for causing neonatal diarrhea incurring severe economic loss to farmers. The presence of large genome size, segmented nature and absence of proof reading activity of RNA polymerase leads to frequent reassortment and thus emergence of new G and P types with ability of interspecies transmission. Methods: During an epidemiological study (July 2016 to July 2019) 200 diarrheic fecal samples were screened for Bovine Rotavirus A using ELISA and RNA-PAGE. Further, twenty two positive samples for RVA were subjected to molecular detection for VP6, VP4 and VP7 genes. Result: Ten (20/200) and 11(22/200) percent diarrheic fecal samples were found positive using ELISA and RNA-PAGE respectively. Twenty samples found positive in ELISA were also found positive in RNA-PAGE. Amongst which 22 (100%) samples were found positive for VP6, while 15 (68.18%) samples showed amplification for VP4 and VP7 gene. All Rotavirus A positive samples were genotyped by multiplex RT-PCR assay. G1G3 was found to be most predominant (53.33%) followed by G3 (26.66%), while one sample each showed the presence of G1G5 and G3G8 (6.66%). Ten samples showed mixed genotype (66.66%). One sample was non typeable (6.66%). Among the P types, P[11] was the most predominant (73.33%), while one sample each showed the presence of P[5] and P[5]P[11] (6.66%) and 02 samples were non typeable (13.33%). The G and P genotype combination determined in 12 samples were as follows; G3P [11] found in two samples (16.66%), G3P[5] in 01(08.33%), G1G5P[11] in 01(08.33%), G1G3P[11] in 07 (58.33%), while 01 (08.33%) sample had mixed genotype G1G3P[5]P[11] combination.

Diagnostic studies on some infectious diseases affecting skin in bovine and buffaloes calves at EL-Dakahlyia province, Egypt

Background: Infectious cutaneous diseases are major threat of bovine and buffaloes calves in Egypt and cause huge economic impact as a result of hide damage, decreased growth rate and mortality rate. Material & methods: A retrospective study was conducted between October 2016 and January 2020 to identify different infectious diseases affecting skin in 5000 examined bovine calves from ten local dairy farms located at El-Dakahlia province. Clinical signs, morbidity and mortality rates were reported. Gross examination of lesions was applied. Skin biopsies were collected from lesion and surrounding areas and part of these samples fixed in 10% buffered formalin for routine hematoxylin and eosin (H&E) staining. Periodic acid Schiff stain (PAS) and immunohistochemistry (IHC) were also applied for diagnosis. The other part of skin samples was kept at-80°C for viral isolation by real time- polymerase chain reaction (RT-PCR). Results: Four infectious diseases were detected in 2220 examined bovine calves out from 5000 (44.4%) including warts (150 cattle calves), FMD (1500 cattle calves and 500 buffaloes calves), LSD (45 cattle calves and 5 buffaloes calves) and ring worm (20 cattle calves). Special staining using PAS was sufficient to diagnose ring worm. Histopathology and IHC diagnosed few cases infected with LSD that showing inclusion bodies in 10 out of 50 calves (0.2%). No inclusion bodies were seen in any infected specimens with FMD or papillomas. Viral nucleic acids of FMD, papillomatosis and LSD virus were detected in infected skin samples. Conclusion: cattle calves showed higher susceptibility to these infectious skin diseases than buffalo calves. FMD caused higher morbidities than in other diseases. Mortalities were reported with FMD and LSD infection. Histopathology was not sufficient to diagnose viral infection. IHC cannot diagnose LSDV in all infected cases. PCR should be used for accurate detection LSD, FMD and papilloma viral nucleic acids in skin samples.

Laparoscopic Ovum Pick-Up Followed by In Vitro Embryo Production and Transfer in Assisted Breeding Programs for Ruminants.

Simple SummaryIn vitro embryo production from oocytes collected by laparoscopy has the potential of producing more offspring from genetically superior females of ruminant species (e.g., sheep, goats, cervids) or ages (e.g., prepubertal cattle and buffalo) that are too small to be eligible for oocyte collection by the transvaginal ultrasound-guided method used in cows. This article reviews the multiple applications of the technology, how it is done, the pros and cons, the limitations to widespread use, and the envisioned improvements that are expected in the years to come. In small ruminants, where conventional embryo recovery is most commonly done by surgery, the technology offers a less invasive approach, i.e., more animal welfare-friendly and with minimum risks of surgical sequels. Thereby, it enables repeating the procedure in the same animals exponentially more times, resulting in the potential for an increased number of offspring born from elite donors. Furthermore, the emerging most attractive application is for the in vitro production of embryos from prepubertal animals at very young ages, which allows having progeny born from genetically superior donors before they reach the age and weight to be bred for the first time.The potential of laparoscopic ovum pick-up (LOPU) followed by in vitro embryo production (IVEP) as a tool for accelerated genetic programs in ruminants is reviewed in this article. In sheep and goats, the LOPU-IVEP platform offers the possibility of producing more offspring from elite females, as the procedure is minimally invasive and can be repeated more times and more frequently in the same animals compared with conventional surgical embryo recovery. On average, ~10 and ~14 viable oocytes are recovered by LOPU from sheep and goats, respectively, which results in 3–5 transferable embryos and >50% pregnancy rate after transfer. LOPU-IVEP has also been applied to prepubertal ruminants of 2–6 months of age, including bovine and buffalo calves. In dairy cattle, the technology has gained momentum in the past few years stemming from the development of genetic marker selection that has allowed predicting the production phenotype of dairy females from shortly after birth. In Holstein calves, we obtained an average of ~22 viable oocytes and ~20% transferable blastocyst rate, followed by >50% pregnancy rate after transfer, declaring the platform ready for commercial application. The present and future of this technology are discussed with a focus on improvements and research needed.