peer reviewed | The purpose of this work was to study electrocardiographic features of double-muscled beef cattle. Electrocardiograms were recorded on one to six occasions from each of a group of 18 conventional calves of the Friesian breed and 29 double-muscled calves of the Belgian White and Blue breed. Ages of the calves at the times of examination ranged from eight to 348 days. The Holmes semi-orthogonal lead system was used. The waves and interval durations and the tridimensional P, QRS, and T modal vector orientation and amplitude were calculated. The magnitude of the cardiac vectors was significantly lower and the ventricular waves and QT interval duration significantly shorter in the double-muscled than in the conventional calves. The P modal vector pointed significantly less downwards and the QRS modal vector pointed significantly more forwards and less up- and rightwards in the Belgian White and Blue, than in the Friesian group. Most of the observed differences might be a consequence of the bodily, and more specifically the thoracic, conformation of the former calves. However, the lower cardiac vector magnitude and shorter wave and interval durations might also reflect lower cardiac mass in the double-muscled subjects. | Le but de cette étude était d'etudier les spécificités électrocardiographiques des bovins de boucherie de conformation hypermusclée. Des enregistrements électrocardiographiques ont été réalises de une a six reprises chez chacun des 18 veaux conventionnels de la race Frisonne et des 29 veaux hypermusclés de la race Blanc Bleu Belge investigués et repartis en deux groupes. L'âge des veaux au moment des investigations était compris entre huit et 348 jours. Le système de dérivation semiorthogonal de Holmes a été applique. La durée des ondes et des intervalles électro-cardiographiques ainsi que l'orientation et l'amplitude des vecteurs cardiaques tridimensionnels P, QRS et T ont été calculées. L'amplitude des vecteurs cardiaques était significativement plus petite et la durée des ondes ventriculaires et de l'intervalle QT significativement plus courte chez les veaux hypermusclés que chez les veaux conventionnels. Le vecteur P était oriente dans une direction significativement moins ventrale et le vecteur QRS dans une direction significativement plus craniale et moins dextro-dorsale chez les veaux hyper musclés que chez les veaux conventionnels. La plupart des différences observées pourraient être attribuées a une conformation corporelle, et particulièrement thoracique, spécifique chez les veaux hyper musclés. Cependant, la plus faible amplitude des vecteurs cardiaques et la durée plus courte des ondes et intervalles électro-cardiographiques pourraient également constituer le signe d'une réduction de la masse myocardique chez ces derniers.

Differing conditions in captive breeding and in the wild have impact on the mineral profile of the pheasant carcass and its heavy metal contents. This may be an indicator of environmental contamination. The study evaluated the nutritional composition and selected macro- and trace element contents (heavy metals in particular) in usable sections of pheasant breast and thigh muscles originating from captive breeding and wild birds. The tests were performed on the breast and thigh muscles of 20 wild and 20 farm bred birds from around Lublin, Poland, with equal sex representation. The nutrient and lead, cadmium, chromium, and nickel contents were determined using inductively-coupled plasma atomic emission spectroscopy. The farmed pheasants had a higher proportion of breast muscle. The thigh muscles of all birds had a higher fat content than the breast muscles (5.1 g vs. 3.4 g per kg of natural weight). The macroelement level depended on the muscle type and bird origin. The trace element content also did and gender dependence was also evident. The wild birds contained more cadmium in the breast muscles and lead in both muscles than the farm-raised ones. The high quality and usefulness of wild and farmed pheasant meat is confirmed. It has advantageous macro- and trace element contents and permissible heavy metal contents except for lead in wild birds. The heavy metal level can be a bioindicator of their environmental occurrence. In wild birds, the lead level may also reflect birdshot remnants.

The aim of the study was to describe the process of neuron death in the cerebral cortex caused by embryonic carbofuran exposure. 81 mouse foetuses from 27 breeding mice were used in the study. Carbofuran was administered by gavage from the 6ᵗʰ to the 15ᵗʰ day of gestation to two groups: one at 0.0208 and the other at 0.0417 mg/kg b.w. On the 17ᵗʰ day, the mice were sacrificed and the foetuses were taken to measure the ROS (malondialdehyde/MDA and superoxide dismutase/SOD) activity in brain tissue, the number of apoptotic embryonic cerebral cortex neurons using a TUNEL assay, and necrotic cells using HE staining. Examination of p53 and caspase 3 expression was done by immunohistochemistry. Data were analysed using analysis of variance (ANOVA) and Duncan’s test. Increased activity of cerebral ROS characterised by significant elevation of the MDA level (P < 0.05), decreased SOD (P < 0.01), increased p53 and caspase 3 expression, and cerebral cortical neuron death either by necrosis or apoptosis (P < 0.05) were found. At the low dose carbofuran increased expression of p53, caspase 3, and apoptosis. At the high dose it increased levels of MDA and necrosis. Increased expression of p53 and caspase 3 and apoptosis indicated that carbofuran may cause apoptosis through the intrinsic pathway. The increased apoptosis grants an opportunity to prevent and treat the effect of ROS due to gestational carbofuran exposure.

The diseases in poultry cause huge losses in the form of mortality in acute infections or as substandard performance due to chronic illness. Biosecurity and vaccination are considered as two important primary strategies for disease prevention in poultry. On the other hand, breeding for disease resistance is an alternate strategy to combat the damages of diseases. Although, attempts were initiated to develop disease resistant poultry by breeding almost a century before, this branch of science renewed the interest among scientists because of catastrophic emerging and reemerging diseases like Avian influenza. It has proven over a period of time that poultry  exhibits genetic resistance to viral diseases like avian leukosis complex, Marek’s disease, avian influenza and Newcastle disease, bacterial disease like salmonellosis and may parasitic infestations. The key genes responsible for resistance to specific diseases have also been demonstrated. The breeding attempts for developing disease resistant poultry has yielded positive results with varying degree of success. The advent of sophisticated molecular methods like genomic selection using highdensity SNP chips, RNA-seq technique and identification of key marker genes and transgenesis could complement the conventional breeding methods to a larger extent in developing disease resistant poultry.

An attempt was made to document the management practices of the backyard goat production in Cauvery Delta zone of Tamil Nadu. The primary data were collected by interviewing 180 backyard goat farmers selected by multi-stage random sampling using pre-tested interview schedule and analyzed through descriptive statistics. About 46.11 per cent of the respondents kept their animals under open system of housing and floor of the goat shed was mud type in 96.67 per cent of the sampled farmers. All the farmers stored manure in an open place. Majority of goat farmers raise their goats solely on browsing and grazing stubble of field crops, natural pasture and tree leaves. Majority of farmers did not possess their own breeding buck but they use community buck for breeding purpose. Middlemen (57.22 per cent) played a major role in marketing of goat in all categories of flocks, followed by butcher (36.11 per cent). Only one-fifth of flock owners dewormed their flocks yearly twice. None of the sample respondents vaccinated their goat against infectious diseases. Goats were marketed round the year (87.78 per cent) and about 12 per cent marketed their goats on special occasions. The major reasons for marketing was found to be the want of money to overcome financial problem (61.07 mean score) in case of bucks / male kids and culling due to old age (66.00 mean score) in case of breeding does. Majority of the sample backyard goat farmers did not follow scientific  management practices at their farm level, which warrants intensive extension programmes. Implementation of best management practices among backyard goat farmers in Cauvery Delta zone of Tamil Nadu would improve the profitability.

Porcine reproductive and respiratory syndrome virus (PRRSV) can be devastating to commercial breeding operations. The objective of this study was to evaluate a novel European PRRSV vaccinal strain for safety and efficacy in bred gilts. In 2 experiments, 110 gilts were vaccinated intramuscularly and the vaccine was evaluated for safety and efficacy. Gilts in Experiment 1 were evaluated for local and systemic reactions and gilts in both experiments were observed for clinical signs of disease through farrow. In both experiments, piglet clinical observations, piglet average daily weight gain (ADWG), gilt serology [determined by enzyme-linked immunosorbent assay (ELISA)], gilt and piglet viremia [determined by quantitative real-time polymerase chain reaction (qPCR)], as well as piglet lung lesion scores and PRRS virus in lung tissue (qPCR) were determined. The vaccine was shown to be safe as there were no significant differences among groups in either experiment. Efficacy was established in Experiment 2 as both vaccinated groups were associated with desirable significant differences in percentage of gilts with abnormal clinical findings; gilt viral load post-challenge [day 125, day of farrowing (DOF), and DOF + 13]; percentages of alive, healthy live, weak live, and mummified piglets per litter at farrowing and weaning; percentage of piglets per gilt that were positive for viremia; percentage of piglets per gilt with clinical disease; and piglet viral load on DOF. It was concluded that a vaccine formulated from the PRRSV modified live virus (MLV) strain 94881 is a safe and effective method of protection against the detrimental effects of virulent PRRSV infection in breeding female pigs.

Pododermatitis is a disease of concern for mink breeders in Canada and worldwide, as it causes discomfort and lowers the breeding rates on farms affected by the disease. Unfortunately, the etiology and pathogenesis of pododermatitis are still unknown. In this study, we compared Staphylococcus spp. and Streptococcus canis isolates from healthy mink with isolates from animals with pododermatitis on 2 farms in Ontario. Almost all hemolytic Staphylococcus spp. isolated were shown to be Staphylococcus delphini Group A by 16S ribosomal ribonucleic acid (rRNA) sequence analysis and polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE) did not reveal any S. delphini or S. canis clonal lineages specifically associated with pododermatitis, which suggests that these bacteria do not act as primary pathogens, but does not dismiss their potential roles as opportunistic pathogens. While S. delphini and S. canis were the most prevalent bacterial pathogens in mink pododermatitis, they were also present in samples from healthy mink. Arcanobacterium phocae is occasionally isolated from pododermatitis cases, but is difficult to recover with conventional culture methods due to its slow growth. A quantitative real-time PCR was developed for the detection of A. phocae and was tested on 138 samples of footpad tissues from 14 farms. The bacterium was detected only in pododermatitis-endemic farms in Canada and was at higher concentrations in tissues from infected footpads than in healthy tissues. This finding suggests that A. phocae is involved in the pathogenesis of pododermatitis.

Objective—To determine the chemoprophylactic effect of gallium maltolate on the cumulative incidence of pneumonia caused by Rhodococcus equi infection in foals. Animals—483 foals born and raised on 12 equine breeding farms with a history of endemic R equi infections. Procedures—Group 1 foals were treated with a placebo and group 2 foals were treated with gallium maltolate (approx 30 mg/kg, PO, q 24 h) during the first 2 weeks after birth. Foals were monitored for development of pneumonia attributable to R equi infection and for adverse effects of gallium maltolate. Results—There were no significant differences in the cumulative incidence of R equi pneumonia among the 2 groups. Conclusions and Clinical Relevance—Chemoprophylaxis via gallium maltolate administered orally at approximately 30 mg/kg daily for the first 2 weeks after birth failed to reduce the cumulative incidence of pneumonia attributable to R equi infection among foals on breeding farms with endemic R equi infections. Further investigation is needed to identify strategies for control of R equi infections.

Age-related changes in skin color and histologic features of hairless descendants of Mexican Hairless dogs were investigated and compared with those of haired descendants of Mexican Hairless dogs and Beagles. According to age, dogs studied were allotted to 4 groups: 0 to 2 weeks, 4 to 5 months, 1 to 1.5 years, and 3 to 4 years old. Skin color, histologic features, and numbers of dihydroxyphenylalanine (DOPA)-positive melanocytes were examined. The luminance values measured, using a spectrophotometer, decreased with advancing age up to 1.5 years, but they increased again at 3 to 4 years in hairless dogs. The number of DOPA-positive melanocytes in hairless dogs decreased with advancing age, whereas there were no DOPA-positive melanocytes in haired dogs and Beagles. Histologically, the epidermis of newborn hairless pups was thick. The border between the epidermis and dermis was wavy, and epidermal ingrowths were found projecting into the dermis. As hairless dogs grew older, the epidermis became thinner and flatter. Although numbers of hair follicles and sebaceous and apocrine sweat glands were apparently fewer in hairless dogs than in haired dogs and Beagles, these structures were detected at least up to 4 years of age. On the other hand, haired dogs and Beagles had a thin epidermis at birth and aging had little effect on their epidermal structures. The dermis of hairless dogs contained fewer mast cells than did that of haired dogs and Beagles.

The study reported here was part of a long-term investigation of the effects of genotype on growth, reproduction, and metabolism in cattle grazing common Bermuda grass and endophyte-infected fescue pastures. In June 1990, blood samples were collected from the tail vein of yearling heifers and steers (Angus [AA], Brahman [BB], and their reciprocal crosses [AB, BA], n = 97). Serum amylase activity was assayed enzymatically; serum Ca and Mg concentrations were determined by atomic absorption spectrophotometry. The effects of endophyte-infected fescue depended on genotype (P < 0.001). In yearlings having at least 1 Angus parent (AA, AB, BA), grazing endophyteinfected fescue was associated with higher serum amylase activity than was grazing Bermuda grass. But serum amylase activities of BB yearlings consuming either forage were similar. Moreover, for either forage, substantial differences were related to genotype (P < 0.007) and gender (P < 0.05). Angus yearlings had higher serum amylase activity than did Brahman yearlings; AB and RA yearlings had intermediate values. Heifers had higher amylase activity than did steers. The relationship among serum values of amylase, Ca, and Mg depended on forage. Yearlings consuming endophyte-infected fescue and having at least 1 Angus parent had a moderate negative correlation between serum amylase activity and Ca concentration (r = -0.53; P < 0.0005); that is, in calves of genotypes with increased amylase activity while consuming endophyte-infected fescue (AA, AB, BA), the higher the amylase activity, the lower the serum Ca concentration. However, in yearlings consuming Bermuda grass, serum amylase and Ca values were not correlated. Conversely, grazing Bermuda grass was associated with moderate positive correlation between Ca and Mg concentrations (r = 0.46; P < 0.0003), but in yearlings grazing endophyte-infected fescue, Ca and Mg concentrations were independent. The cause, pathophysiologic mechanism, and clinical importance of these effects remain to be determined. In conclusion, serum amylase activity in yearling cattle was influenced by genotype, gender, and consumption of endophyte-infected fescue. We speculate that yearlings having at least 1 Angus parent may develop a persistent subclinical derangement of the exocrine portion of the pancreas when exposed to common environmental toxins associated with endophyte-infected fescue grass, and that purebred Brahman yearlings can resist this aspect of fescue toxicosis.