New Zealand Holstein-Friesian cows (n = 4) were used to quantify the importance of endogenous synthesis of cis-9, trans-11 conjugated linoleic acid (CLA) via Delta(9)-desaturase in cows fed a fresh pasture diet. The experiment was a 4 x 4 Latin square design with treatments arranged in a 2 x 2 factorial. Treatments lasted 4 d and were pasture only, pasture plus sterculic oil, pasture plus sunflower oil, and pasture plus sunflower oil plus sterculic oil. Abomasal infusion of sterculic oil inhibited Delta(9)-desaturase and decreased the concentration of cis-9, trans-11 CLA in milk fat by 70%. Using the changes in cis-9 10:1, cis-9 12:1 and cis-9 14:1 to correct for incomplete inhibition of Delta(9)-desaturase, a minimum estimate of 91% of cis-9, trans-11 CLA in milk fat was produced endogenously in cows fed fresh pasture. Dietary supplementation of a pasture diet with sunflower oil increased the proportion of long chain fatty acids in milk fat; however, the increase in vaccenic acid concentration was small (18%) and there was no increase in cis-9, trans-11 CLA concentration. Overall, results show that endogenous synthesis is responsible for more than 91% of the cis-9, trans-11 CLA secreted in milk fat of cows fed fresh pasture. However, the failure of plant oil supplements to increase the concentration of cis-9, trans-11 CLA in milk fat from pasture-fed cows requires further investigation.

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Felis catus papillomavirus 2 (FcaPV-2) causes premalignant skin lesions in cats and has also been found in a proportion of cutaneous squamous cell carcinomas (SCCs) -a common and potentially fatal cancer of cats. Whilst this could suggest a role of the virus in cancer development, FcaPV-2 has also been detected in skin swabs of normal cats, making it difficult to discern whether the papillomavirus is causing the cancer or merely an 'innocent bystander'. To distinguish between these two possibilities, real-time PCR was used to determine the viral copy number and the transcriptional activity of FcaPV-2 infections present in 70 formalin-fixed paraffin-embedded skin lesions including 10 papillomavirus-induced premalignant lesions and 60 SCCs. FcaPV-2 gene expression was found in 21 of 60 (35 %) SCCs, all 10 premalignant lesions and none of 10 normal skin samples. The results showed two distinct subsets of SCCs. The majority of the SCCs had low copy numbers of FcaPV-2 DNA (mean of 17 copies per copy of reference gene DNA) and no FcaPV-2 gene expression, suggesting the virus was an incidental finding. In contrast, 20 SCCs had detectable FcaPV-2 E6/E7 gene expression and very high copy numbers of FcaPV-2 DNA, with a mean of 32 930 copies per copy of reference gene DNA. The relative quantity of E6/E7 gene expression and the viral copy number in this group were similar to those found in the papillomavirus-induced premalignant lesions, suggesting that FcaPV-2 may play a role in the development of a subset of feline cutaneous SCCs.

The pasture probe, rising plate meter (RPM), ward height and visual assessment methods were compared for the estimation of the herbage mass of dairy pastures. The pasture probe and calibrated visual assessment were slightly more accurate than others. Visual assessment without calibration was less accurate than all other methods. There was little difference between operators of the pasture probe and RPM, but operator variation was large with visual assessment. Variation between calibrations from different days, seasons, and sites was large. Only dead material content was identified to influence this variation. Pooling of calibrations, double sampling procedures, and derivation of different calibration slopes for each day from an equation fitted to calibration data are procedures discussed for the estimation of herbage mass by farmers, advisors and researchers. Wide adoption of methods such as the pasture probe or RPM with "universal" calibrations could reduce inconsistent advice offered to farmers, and can be used with confidence. Keywords: capacitance probe, rising plate meter, visual assessment, ward height, grassland management, pasture composition, pasture assessment.

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The objective of this study was to determine whether the differences in the composition of milk from cows of different beta-lactoglobulin beta-LG) phenotypes are affected by the amount of pasture available and, hence, pasture dry matter intake. Twenty-two Friesian cows of each of the AA and BB variants of the beta-LG phenotype were subjected to ad libitum grazing or restricted grazing in crossover experiments during spring (early lactation, approximately 60 d in milk) and summer (mid to late lactation, approximately 180 d in milk). Milk samples were collected from each cow at the end of each 8-d treatment period and analyzed for composition. Cows of the AA variant of the beta-LG phenotype had higher concentrations of whey protein and beta-LG, but lower concentrations of casein (CN), alpha-CN, kappa-CN (summer only), and BSA, than cows of the BB variant. Compared with cows with a restricted allowance, cows grazing ad libitum had higher milk yields and concentrations of protein, casein, whey protein, and all individual proteins except BSA and immunoglobulin. There were no interactions between effects of pasture allowance and phenotype on milk yield or composition. The data show that having adequate pasture for grazing cows is important not only to maximize milk yield, but also to optimize concentrations of protein and casein, and hence the manufacturing potential of milk. Further, the differences in composition of milk from cows of differing beta-LG phenotypes persisted during short-term restrictions in pasture allowance, and between spring and summer.

Papillomaviruses (PVs) are well established to cause hyperplastic papillomas (warts) in humans and animals. In addition, due to their ability to alter cell regulation, PVs are also recognized to cause approximately 5% of human cancers and these viruses have been associated with neoplasia in a number of animal species. In contrast to other domestic species, cats have traditionally been thought to less frequently develop disease due to PV infection. However, in the last 15 years, the number of viruses and the different lesions associated with PVs in cats have greatly expanded. In this review, the PV life cycle and the subsequent immune response is briefly discussed along with methods used to investigate a PV etiology of a lesion. The seven PV types that are currently known to infect cats are reviewed. The lesions that have been associated with PV infections in cats are then discussed and the review finishes with a brief discussion on the use of vaccines to prevent PV-induced disease in domestic cats.