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Vitamin A is an essential nutrient and is well established to be crucial for regulating hematopoiesis, epithelial integrity, vision, and embryogenesis. In humans, vitamin A deficiency is associated with increased risk of morbidity, mortality, and a decreased immune response to vaccines. However, despite being the first vitamin discovered, little is known about its role in these outcomes in dairy cows. Dairy cows experience a significant decrease in serum vitamin A concentrations at the time of calving when cows are most at risk for disease. Previous study findings show conflicting results as to the effects of vitamin A and diseases such as mastitis in dairy cows. However, many studies with negative results are limited by their small sample size and short study period. The objective of this study was to investigate the associations between vitamin A and known disease biomarkers for fresh cow diseases as well as incidents of disease., American Association of Bovine Practitioners Proceedings of the Annual Conference, 2019

CYP enzyme induction is a sensitive biomarker for phenotypic metabolic competence of in vitro test systems; it is a key event associated with thyroid disruption, and a biomarker for toxicologically relevant nuclear receptor-mediated pathways. This paper summarises the results of a multi-laboratory validation study of two in vitro methods that assess the potential of chemicals to induce cytochrome P450 (CYP) enzyme activity, in particular CYP1A2, CYP2B6, and CYP3A4. The methods are based on the use of cryopreserved primary human hepatocytes (PHH) and human HepaRG cells. The validation study was coordinated by the European Union Reference Laboratory for Alternatives to Animal Testing of the European Commission’s Joint Research Centre and involved a ring trial among six laboratories. The reproducibility was assessed within and between laboratories using a validation set of 13 selected chemicals (known human inducers and non-inducers) tested under blind conditions. The ability of the two methods to predict human CYP induction potential was assessed. Chemical space analysis confirmed that the selected chemicals are broadly representative of a diverse range of chemicals. The two methods were found to be reliable and relevant in vitro tools for the assessment of human CYP induction, with the HepaRG method being better suited for routine testing. Recommendations for the practical application of the two methods are proposed.

An archaeological watching brief was undertaken on a water renewal scheme in the centre of Stalybridge. It was thought that groundworks may reveal the remains of Castle Hall House, shown on the 1850 Tithe Map, and demolished in 1861 may be encountered. No archaeolgoical finds/features were observed.

Many management practices can be utilized to maximize weight and increase value of calves at weaning. Combining the two management practices of castration and implanting male calves allows producers to maximize weaning weights and avoid discounts for intact males. Crossbred bull calves were randomly assigned at birth to 1 of 3 treatment groups: castrated (n = 22), banded (n = 18) or left intact (n = 20). Calves that were castrated or banded within 24 h after birth received a zeranol implant at that time. Calves in the intact group were castrated at 150 days of age and then implanted, and the calves in the other 2 treatment groups were re-implanted at that time. There were no differences in weaning weight, average daily gain (ADG) or weight per day of age between the 3 treatment groups. Castrating calves shortly after birth reduced stress on the animal compared to castration at a older age (day 150 to weaning). Also, early castration may be more acceptable as an animal welfare issue. It is concluded that combining castration and implanting allows producers to maximize weaning weight of calves as well as reduce the stress of castration at an older age., The Bovine Practitioner, Vol. 34, No. 2 (2000 May)