The clinical expression and emergence of porcine circovirus 2

Since its discovery and characterization in western Canada in 1995, the distribution of post-weaning multisystemic wasting syndrome (PMWS) has grown and the syndrome is undoubtedly recognized worldwide. More recently, there is a heightened interest in several potentially related conditions including porcine dermatitis and nephropathy syndrome (PDNS), proliferative and necrotizing pneumonia (PNP), congenital tremors (CT-AII), perinatal myocarditis and reproductive failure. Although the causality of porcine circovirus type 2 (PCV2) has recently been proven [Vet. Pathol. 37 (2000) 254; J. Comp. Pathol. 122 (2000) 9; J. Vet. Diagn. Invest. 13 (2001) 185], PCV2 is present in both diseased and healthy pig populations. Furthermore, recent serologic studies have shown that there are no significant differences in PCV2 specific IgG titres between PMWS clinical and non-clinical herds (Harding et al., in press). Clearly, the transmission, epidemiology, and factors triggering clinical expression are poorly understood. With these uncertainties in mind, the objective of this paper is to review the clinical expression and emergence of PMWS and the potentially associated disease syndromes including PDNS.     

Estimation of genetic parameters among reproductive and growth traits in yearling heifers

Growth and reproductive data were obtained on 779 beef heifers at the San Juan Basin Research Center, Hesperus, Co. Genetic parameters were estimated for age of puberty (AOP), age of first calving (AOC), julian day of first calving (DOC), julian day of second calving (DOSC), birth weight, weaning weight, yearling weight, and average daily gain from weaning to yearling and to cycling weights. The least squares model included birth year, age of dam and breed as fixed effects, sire/breed as a random variable, and day of birth and percent inbreeding as covariates. Day of birth was not included in the analyses of AOC, DOC or DOSC. Paternal half-sib estimates of heritability were: AOP, .10 +/- .17; AOC, .01 +/- .12; DOC, .09 +/- .13 and DOSC, .36 +/- .18. Genetic and phenotypic correlations were generally favorable, but genetic correlations were variable with large standard errors. Inbreeding had a detrimental effect on reproductive traits, and a seasonal effect was present for AOP.     

A comparative study on certain enzymes of the granulocyte from different ruminant species

In the present study the level of enzyme hydrolases (alkaline phosphatase, myeloperoxidase, elastase, arginase, lysozyme and β-galactosidase) of polymorphonuclear cell (PMN) granules in different ruminant species and their release in response to activation was studied. Buffalo PMN alkaline phosphatase activity was higher (P < 0.01) than in PMNs of cattle and goats. Interestingly, myeloperoxidase was higher in cattle PMNs and least in goat PMNs (P < 0.01), a similar pattern was observed in the distribution of enzyme arginase. As far as lysozyme is concerned, its activity was significantly higher (P < 0.01) in PMNs of buffaloes than in the case of cattle and goat PMNs. On activation, these cells released MPO and elastase, in all the species studied, while lysozyme was secreted only in buffalo PMN cells. Activity of certain enzymes related to oxidant defence systems such as glutathione peroxidase and glutathione reductase were higher in cattle and goats compared to that in buffaloes. These observations are likely to have bearing on immunodefense roles played by PMNs and reflected differences among the ruminant species studied.     

A RETROSPECTIVE STUDY OF OSTEOMYELITIS IN DOGS AND CATS

Thirty-nine cases of osteomyelitis in dogs and cats were recorded at the Sydney University Veterinary Hospital and Clinic over a three and a half year period. In 36 cases osteomyelitis was established prior to admission. Three cases of osteomyelitis became established from a total of 502 orthopaedic surgery cases seen at the hospital in this period. In the dog the most common source of infection was open reduction of closed fractures, while in the cat, the most common source of infection was an extension from soft tissue infection. More males than females were affected. Ten cases of osteomyelitis were treated successfully, twelve cases required amputation, while euthanasia was performed on thirteen other cases. The problems and principles of treatment of active osteomyelitis as reflected in the treatment of this series of cases have been described.