Evaluation of the mineral status of cattle on communal grazing in the North West Province of South Africa.

Twenty five cattle were randomly selected from a herd of animals grazing communally around Mogosane village in the North West Province to evaluate their mineral status based on blood and faecal analysis. Mean faecal phosphorus (P) concentration was curvilinear, increasing from July (0.99 mg/g) to December (3.

Bone mineral response to ammonium sulphate offered as a lick supplement in beef calves.

Sixteen Bonsmara calves (4 males, 12 females) between 10 and 18 months of age were blocked according to age and sex and randomly assigned to 2 groups. They were offered licks containing bone meal and salt (50:50 ratio) (control) and bone meal and ammonium sulphate (NH4SO4) at 1.25, 2.

Bone, blood and faecal response to an acidogenic lick for range cattle using different concentrations of ammonium chloride.

Thirty Brahman-Angus cross heifers at breeding age on extensive grazing were used to test the effectiveness of NH4Cl as an acidogenic agent at 15,18, 21 and 26 % of a dicalcium phosphate lick (A+), compared to a lick of 5 parts dicalcium phosphate and 3 parts salt (A-). Blood and faecal phosphorus (P), faecal calcium (Ca) and faecal magnesium (Mg) were significantly (P<0.05) higher in A+ compared to A-animals at different stages of the experiment.

The effect of gestation and lactation on bone calcium, phosphorus and magnesium in dairy cows.

A study was conducted to monitor changes in cortical bone mineral in the dairy cow in response to demands of lactation and pregnancy using rib bone biopsies in serial sampling. Sixteen Friesian cows from the University dairy herd were used to collect 9 samples during the lactation period and 5 samples during the dry period. The data were analysed using a split-plot design analysis of variance.

Acute effects of an anionic diet on bone mineral homeostasis in the bovine.

Fifteen Friesian oxen between 12 and 18 months of age with a mean body mass of 240.7 kg were randomly assigned to diets containing 0.25% phosphorus (P) or less to evaluate the acute effects of an acidiogenic diet of -11.