Moredun Foundation

In this chapter, developments at the interface between mineral nutrition in animals and humans are considered: the particular relationship between mineral nutrition of of livestock that affects humans or human activity that affects the mineral nutrition of livestock which includes: the impact of the mineral nutrition of livestock on the environment; the impacts of climate change on mineral nutrition of livestock and of livestock production on climate change; manipulating the composition of edible products to enhance market value; the impact of regulations to reduce hazards to humans on animal production; and applying advances in assessing mineral status in humans to animals.

BOVINE viral diarrhoea virus (BVDV) is an outstandingly successful virus. It is best known as the cause of a variety of clinical conditions resulting in economic losses in cattle, but understanding its biology has shown that BVDV and other pestiviruses have features unique among viruses. View this table: Veterinary Record publication times BVDV causes both transient and persistent infections and can escape the host's immune responses during both events. Transient infection occurs in cattle of all ages. Oronasal infection results in transient viraemia and virus excretion is low before it is eliminated by a standard immune response. The innate interferon response is followed by adaptive cell-mediated and humoral responses so that specific anti-BVDV antibody can be detected within three weeks of infection. Antibody levels continue to rise over the next two months and a solid immunity to that virus is maintained for years. However, if infection occurs in a pregnant animal, the virus escapes by crossing the placenta to the fetus where it infects a wide variety of cells without killing them. The tight bovine placentation prevents the dam's immune response from assisting the fetus. Before 120 days' gestation, a fetus lacks a mature adaptive immune response; all viral antigens are accepted as ‘self’ and are forever seemingly ignored by the fetus' or calf's cell-mediated and humoral adaptive responses. The fetus is immunotolerant to those viral antigens and will not respond to them throughout the rest of its life. The virus has simply escaped the host's adaptive immune response resulting in an animal that is persistently infected. The virus also has to circumvent the host's innate immune response, which is fully functional from the embryo's early development, from the first day of fetal infection throughout the host's life. BVDV is able …

Abstract The sources, functions, and metabolism of calcium in livestock and poultry animals are discussed. Highlights of the chapter focused on the importance of calcium for dairy cows as well as on the diagnosis and treatment of calcium disorders in animals.

Abstract In this chapter, the factors that affects mineral absorption in livestock as well as ways of controlling mineral intake in animals are discussed. Topics include: selective grazing, diet selection, clinical and pathological changes, biochemical indicators of mineral deprivation, differentiation of mineral deprivation, criteria of dysfunction, physiological and developmental effects, functional forms and indices, correction of mineral imbalance, mineral supplementation, and mineral sources.

Abstract In this chapter the significant role played by potassium in livestock and poultry animals was discussed with emphasis on the functions, dietary sources (forages, concentrates, roots and by-products), absorbability, requirements, metabolism, excretion, deficiencies, and its toxicity in animals.

Abstract This chapter presents the functions, metabolism, and risk factors involved in supplementing the diets of farm animals with the potentially toxic elements (aluminium, arsenic, cadmium, fluorine, lead, and mercury).

The concentrations of trichloroacetic acid (tca)-soluble copper and caeruloplasmin were determined in 345 serum samples taken from cattle in March 1998 by eight Scottish Agricultural College veterinary disease surveillance centres serving areas with soils ranging from being ‘high’ in molybdenum (Thurso) to ‘low’ (Perth and St Boswells). The mean concentrations varied significantly between the centres, with Thurso having the lowest values for both variables. There were strong linear regressions (r>0·8) between caeruloplasmin and tca-soluble copper for each centre but no significant differences in slope or intercept between the areas with the highest and lowest soil molybdenum, and the pooled regression accounted for 88 per cent of the variation. The distribution of the ratios of caeruloplasmin to tca-soluble copper, unlike those of the individual variables, was not normal, and 70 per cent of the values fell within 10 per cent of the mean ratio of 20·3 mg/μmol and close to the 22 mg/μmol copper expected in pure caeruloplasmin. Low ratios were generally associated with low tca-soluble copper. Ratios above 24 were found in 8 per cent of the samples and were probably attributable to acute-phase reactions and the non-specificity of the assay for caeruloplasmin.