A meta-analysis comparing the effect of vaccines against Mycoplasma hyopneumoniae on daily weight gain in pigs

Our aims were to evaluate the published literature concerning the effect of swine vaccination against Mycoplasma hyopneumoniae on the average daily weight gain (ADWG). This was done by re-evaluating the influence of selected factors on ADWG by a meta-analysis of published studies from 1991 to 1999, fulfilling certain inclusion criteria.With ADWG as the outcome, an analysis of variance was performed for such variables as treatment, vaccination schedule, age during study, housing system and publication quality. Each clinical trial was considered as a random effect and the numbers of pigs in each trial were weightings.Of 63 published studies, 16 describing three commercial vaccines fulfilled the criteria for the meta-analysis. Due to few studies with one of the vaccines (n=3), only two vaccines were included.Vaccinated pigs gained an average of 592g (S.E.=15) with Stellamune and 590g (S.E.=15) with Suvaxyne compared to non-vaccinated pigs that gained an average of 569g (S.E.=14)(P<0.01) when adjusted for age during the study. Vaccine type, vaccination schedule, housing system and publication quality were not significantly associated with ADWG.     

Sprain of the short radial collateral ligament in a racing greyhound

Severe carpal lameness in a racing greyhound due to a sprain of the straight part of the short radial collateral ligament is described. The dog subsequently developed an enthesiopathy at the origin of the ligament. Treatment was by kennel rest and the dog returned to successful racing.     

In vitro effects of beta-hydroxy-beta-methylbutyrate (HMB) on cell-mediated immunity in fish

beta-Hydroxy-beta-methyl butyrate(HMB) has been shown to counteract many of the negative effects of intensive animal production methods and results in increased growth and protection against diseases. In the present study, the effect of HMB on the immunocompetence cell activity in rainbow trout (Oncorhynchus mykiss) and carp (Cyprinus carpio) was examined. Pronephric phagocytes and lymphocytes were isolated from the fish and grown in culture medium (RPMI-1640) containing either 0, 0.1, 1, 5, 10, 25, 50 or 100 microg HMB/ml of medium. The effects of HMB on the respiratory burst activity (RBA) stimulated by phorbol myristate acetate (PMA), the potential killing activity (PKA) and lymphocyte proliferation stimulated by either concanavalin A (Con-A) or lipopolysaccharide (LPS) were examined. The addition of HMB to the culture medium increased the RBA by up to 84% (p<0.01) over that of cells grown without HMB. Similarly, the PKA of the phagocytes was also increased with HMB addition to the medium by up to 140% (p<0.01) over that of cells grown without HMB. Lymphocyte proliferation stimulated by both ConA and LPS was also increased approximately two-fold (p<0.01) when HMB was added to the culture medium at concentrations between 10 and 100 microg HMB/ml in both rainbow trout and carp. The greatest effects of HMB on RBA and PKA activities were observed at a concentration >50 microg HMB/ml while lymphocyte proliferation was maximally stimulated at 25 microg HMB/ml. In conclusion, the current study shows that HMB could potentially improve immunocompetence cell activity in fish through increased cell proliferation and functionality.     

Equine bullous pemphigoid IgG autoantibodies target linear epitopes in the NC16A ectodomain of collagen XVII (BP180, BPAG2)

Bullous pemphigoid (BP) is an autoimmune subepithelial blistering dermatosis of humans, dogs, cats and pigs. It is characterized by skin-fixed and circulating IgG autoantibodies that target one or both BP antigens. An immunological homologue of BP in humans was diagnosed in two horses with cutaneous and mucosal ulcerations as well as microscopic subepithelial vesiculation. Immunological investigations revealed similar findings for both the horses. Direct immunofluorescence demonstrated the presence of IgG deposited linearly at the dermoepidermal junction in mucosal and skin biopsy specimens. Indirect immunofluorescence testing confirmed the existence of circulating basement membrane-specific IgG autoantibodies. Using intact and salt-split epithelial substrates, serum IgG were shown to target antigens situated not only at the basal, but also at the lateral and apical aspects of stratum basale keratinocytes. Immunoblotting and ELISA corroborated that the IgG from affected horses, but not those from normal controls, exhibited high immunoreactivity against the NC16A extracellular domain of type XVII collagen (BPAG2, BP180). Equine BP could be proposed, therefore, as another spontaneous model of this most common basement membrane autoimmune dermatosis of humans.     

Ultrasonography of the equine neonatal kidney

Ultrasonography is important in the clinical examination of the foal. The ultrasonographic appearance and size of the neonatal kidneys were defined and an imaging protocol established in 6 normal Thoroughbred foals (mean age +/- s.d. 5.0 +/- 3.2 days). Characteristically, in both the heart-shaped right kidney and bean-shaped left kidney, the renal cortex was more echogenic than the medulla. The terminal recesses, renal crest and pelvis were identified, as was the ureter, which contained anechoic urine in its lumen. The renal, interlobar and arcuate vessels were seen. For the right kidney, the ultrasonographic probe was placed at the 14-17th intercostal spaces and paralumbar fossa. For the left kidney, the probe was at the 16th or 17th intercostal spaces and paralumbar fossa. Perirenal structures, including the caudate lobe of the liver, the dorsal extremity of the spleen, the adrenals, the aorta and caudal vena cava were also identified. An understanding of the ultrasonographic appearance of the normal neonatal kidney, accompanied by a routine imaging protocol to ensure that all regions of each kidney are examined, permit a more informed interpretation of renal images in the first few days postpartum.     

绿头野鸭与我国主要地方鸭品种遗传多样性研究

利用17个微卫星标记,采用PCR扩增,8%非变性聚丙烯酰胺凝胶电泳、银染,对绿头野鸭种群和我国9个主要地方鸭品种的遗传多样性进行了检测,统计了各群体的平均有效等位基因(Ne)、平均遗传杂合度(H)、多态信息含量(PIC)、群体间的遗传距离(Ds)和相似系数(I)。采用UPGMA和NJ法构建系统发生树。结果表明:17个微卫星座位在绿头野鸭种群和我国9个主要地方鸭品种中的多态信息含量均为高度多态,所有鸭种的平均PIC、H、Ne分别为0.6506、0.6896、4.1±1.5,基因多态性和遗传多样性相对较高;家鸭各品种间的遗传距离在0.1631~0.6844范围内,绿头野鸭与家鸭品种间的遗传距离分别在0.3096~0.8219之间。根据系统发育树推断中国主要地方鸭品种不是单一起源于绿头野鸭。中国主要地方鸭品种大致可以分为5支。一支为北京鸭、荆江鸭,一支为中山鸭、建昌鸭及高邮鸭,一支为靖西大麻鸭和金定鸭,连城鸭为一支,绍兴鸭为另一支。