Potential role of hares in the spread of liver fluke in the Netherlands

Hares (Lepus europeanus) sharing pasture with cattle from six locations in the Netherlands were examined for the presence of liver fluke (Fasciola hepatica) and shown to have prevalences of infection ranging from 0 to 41%. The mitochondrial haplotypes of liver flukes present in the hare populations were determined and compared with those found in cattle from a farm where triclabendazole resistance has been reported. Phylogenetic analysis indicated that the flukes present in the hares belonged to the same clades as those present in the cattle. A consideration of the life cycle of the liver fluke and the seasonal breeding pattern and ecology of hares supports the suggestion that hares may act as a refugia for liver fluke and as a vector for the spread of drug-resistant genotypes.     

Prior and concomitant dehydroepiandrosterone treatment affects immunologic response of cultured macrophages infected with Trypanosoma cruzi in vitro?

DHEA, a steroid hormone synthesized from cholesterol by cells of the adrenal cortex, plays an essential role in enhancing the host's resistance to different experimental infections. Receptors for this hormone can be found in distinct immune cells (especially macrophages) that are known to be the first line defense against Trypanosoma cruzi infection. These cells operate through an indirect pathway releasing nitric oxide (NO) and cytokines such TNF-α and IL-12 which in turn trigger an enhancement of natural killer cells and lymphocytes which finally secrete pro and anti-inflammatory cytokines. The effects of pre- and post-infection DHEA treatment on production of IL-12, TNFα and NO were evaluated. T. cruzi infected macrophages post treated with DHEA displayed enhanced concentrations of TNF-α, IL-12 and NO. Probably, the mechanisms that induced the production of cytokines by infected cells are more efficient when the immune system has been stimulated first by parasite invasion, suggesting that the protective role of DHEA is greater when administered post infection.     

Genetics of hyperpigmentation associated with the Fibromelanosis gene (Fm) and analysis of growth and meat quality traits in crosses of native Indian Kadaknath chickens and non-indigenous breeds

1. The study investigated the extent of hyperpigmentation (a trait fixed in native Indian Kadaknath chickens), bodyweight, carcase quality and leanness at 12 weeks of age in F(1) and back-crosses of Kadaknath with White Leghorn, White Plymouth Rock and Aseel Peela chickens. 2. The objective of the study was to determine if hyperpigmentation was affected by the major gene Fibromelanosis (Fm) and to evaluate the effects of different proportions of Kadaknath genes on growth and carcase quality. 3. The pigmentation pattern of skin indicated that Fm behaved as the primary locus affecting dermal-hyperpigmentation and that the sex-linked Id locus produced an epistatic effect. 4. The results suggested that variable allelic forms of Id were acting in different crosses, which resulted in variation in melanosis of the host. However, no conclusive pattern for shank pigmentation could be explained through genotyping of the Id and Fm loci. 5. Analysis of quantitative traits indicated the positive impact of a Kadaknath genomic proportion of 50% or more on meat texture and carcase leanness. Improvement in leanness occurred in White Rock crosses but not in White Leghorn and Aseel Peela crosses. 6. Thigh-meat texture was influenced more by enhanced Kadaknath genomic proportions than the breast-meat. It was concluded that introgression of Kadaknath genomic proportion beyond 50% in a cross with meat-type chickens, irrespective of the impact Fm, brought improvement in meat quality whereas no such advantage was obtained for growth traits. 7. The beneficial impact of the Kadaknath genome on meat quality calls for further studies to identify causative genes for their selective use to improve meat quality in Kadaknath crossbred chickens.     

Effects of sex and inclusion of dried distillers grains with solubles on slaughter yield and meat characteristics of Pekin ducks

1. The effects of dried distillers grains with solubles (DDGS) dietary inclusion concentration, and sex, on body weight, slaughter efficiency and meat characteristics of Pekin ducks (Anas platyrhynchos f. domestica, strain P55) were studied.

2. Sexed ducklings (n?=?160) were divided randomly into 4 groups (each with 4 replicates). From d 1 to d 21, all the birds received the same commercial feed, then from 22 to 49 d of age the ducks were fed in the following groups: control (commercial feed) and three experimental groups (15%, 25% and 30% inclusion of DDGS). All ducks were weighed individually at d 1, 21 and 49. On the day of slaughter, 5 males and 5 females, of body weight close to the average weight for group and sex, were selected from each group, slaughtered and the following parameters were evaluated: slaughter yield, weight, and percentage of particular elements of carcase, physical and chemical characteristics of meat.

3. The results obtained showed that DDGS included from 22 to 49 d of rearing, at concentrations up to 30%, in a commercial Pekin duck diet did not affect the live body weight, slaughter yield, weight, and percentage of breast and leg muscle, skin with subcutaneous fat, and abdominal fat. There were no differences in physical characteristics (pH₁₅, pH_24, meat colour values L*, a*and b*, and hygroscopicity) of breast muscle, as well as in cholesterol content. DDGS addition at 30% significantly increased fat content in male, and crude protein in female, breast meat. Sex effect was observed only in a few traits and was diet dependent. Final body weight of females fed 30% DDGS was significantly lower than males; in the control and 15% DDGS group females had higher percentage of skin with subcutaneous fat.

4. The results obtained, and relative costs of feeds produced, allows the recommendation of DDGS addition at up to 30% to commercial Pekin duck diets from 22 d of age.     

Echocardiographic Assessment of Left Ventricular Systolic Function in Colic Horses

The use of echocardiography to study hemodynamic disturbances in colic horses has not been reported. The aim of this study was to noninvasively assess the effect of colic-related endotoxin shock on equine cardiac function. Fifty horses were admitted to the clinic on emergency for colic. A shock score from 1 to 4 was established for each horse on the basis of clinical evaluation, noninvasive systolic blood pressure, and blood tests. Left ventricular echocardiographic and Doppler parameters were compared between the four groups according to the shock score (1 = no or discrete signs of shock, n = 11; 2 = mild shock, n = 17; 3 = moderate shock, n = 12; 4 = severe shock, n = 10), using a multivariate analysis. Horses with a shock score of 1 were considered as controls. Significance was set at P < .05. The stroke volume, stroke index, ejection time, ejection time index corrected for heart rate, aortic velocity time integral, aortic flow acceleration time, and aortic flow deceleration time were significantly lower, whereas acceleration rate of aortic flow ejection and heart rate were significantly higher in shocked horses, as compared with the horses in the control group. Cardiac output was not significantly different between groups. Although these results are difficult to interpret because of the shock-induced changes in loading conditions of the heart, they suggest that alterations in some indicators of systolic function can be quantified by Doppler echocardiography in horses with colic-induced endotoxemic shock. Ultrasonographic monitoring of cardiovascular function could therefore be of interest in equine intensive care.     

Comparison of Insulin Sensitivity of Horses Adapted to Different Exercise Intensities

Diets high in concentrates and soluble carbohydrates are associated with reduced insulin sensitivity in horses. Exercise training could protect against diet-induced insulin resistance. The objective of this study was to determine the intensity of exercise training required to affect insulin sensitivity in stabled horses fed a diet high in concentrates but moderate in soluble carbohydrates. In all, 31 stabled horses underwent three different exercise regimens: turnout, light exercise, and moderate exercise, while being fed a diet containing 60% concentrate. Blood was sampled monthly and analyzed for insulin. Insulin sensitivity was assessed using basal insulin concentrations and calculated insulin sensitivity (reciprocal of the square root of insulin) and compared across months by analysis of variance with repeated measures. Insulin sensitivity (reciprocal of the square root of insulin) was higher during periods of moderate and light physical activity as compared with turnout. These results indicate that turnout alone may not be adequate to improve insulin sensitivity in horses fed high amounts of concentrate.     

A retrospective study of the rate of postoperative septic arthritis following 353 elective arthroscopies

Objective : To report the rate of postoperative septic arthritis following elective diagnostic and surgical arthroscopy in small animals within a clinical setting. Methods : A retrospective case review from the case log of one veterinary surgeon. Results : Of the 353 procedures included, performed on 305 animals, there were three cases of postoperative sepsis (0·85%). Clinical Significance : Interventional arthroscopy including both diagnostic and surgical arthroscopy in small animals is a safe technique and poses a risk of postoperative sepsis of approximately 1%.     

Analysis of the effect of the bovine adenosine triphosphate-binding cassette transporter G2 single nucleotide polymorphism Y581S on transcellular transport of veterinary drugs using new cell culture models

In commercial dairy production, the risk of drug residues and environmental pollutants in milk from ruminants has become an outstanding problem. One of the main determinants of active drug secretion into milk is the ATP-binding cassette transporter G2/breast cancer resistance protein (ABCG2/BCRP). It is located in several organs associated with drug absorption, metabolism, and excretion, and its expression is highly induced during lactation in the mammary gland of ruminants, mice, and humans. As a consequence, potential contamination of milk could expose suckling infants to xenotoxins. In cows, a SNP for this protein affecting quality and quantity of milk production has been described previously (Y581S). In this study, our main purpose was to determine whether this polymorphism has an effect on transcellular transport of veterinary drugs because this could alter substrate pharmacokinetics and milk residues. We stably expressed the wild-type bovine ABCG2 and the Y581S variant in Madin-Darby canine kidney epithelial cells (MDCKII) and MEF3.8 cell lines generating cell models in which the functionality of the bovine transporter could be addressed. Functional studies confirmed the greater functional activity in mitoxantrone accumulation assays for the Y581S variant with a greater relative V(MAX) value (P = 0.040) and showed for the first time that the Y581S variant presents greater transcellular transport of the model ABCG2 substrate nitrofurantoin (P = 0.024) and of 3 veterinary antibiotics, the fluoroquinolone agents enrofloxacin (P = 0.035), danofloxacin (P = 0.001), and difloxacin (P = 0.008), identified as new substrates of the bovine ABCG2. In addition, the inhibitory effect of the macrocyclic lactone ivermectin on the activity of wild-type bovine ABCG2 and the Y581S variant was also confirmed, showing a greater inhibitory potency on the wild-type protein at all the concentrations tested (5 μM, P = 0.017; 10 μM, P = 0.001; 25 μM, P = 0.008; and 50 μM, P = 0.003). Differential transport activity depending on the genotype together with the differential inhibition pattern might have clinical consequences, including changes in substrate pharmacokinetics (and subsequently pharmacodynamics) and more specifically, changes in secretion of ABCG2 substrates into milk, potentially implying important consequences to veterinary therapeutics.     

Staying current by searching the veterinary literature

The body of knowledge in veterinary medicine and the biomedical sciences continues to grow logarithmically, and learning about new developments in veterinary medicine requires successful navigation of recently published literature worldwide. This article examines how veterinarians can use different types of automated services from databases and publishers to search the current and past literature, access articles, and manage references that are found.