No abstract

The unsatisfactory nature of the methods adopted in feeding experiments at Animal Nutrition Research Institutes has been shown to be due to the neglect of the worker to control variable factors, other than those being investigated, which affect the growth rate of his animals.It has been proved that age, sex (females and castrated males), condition and previous growth rate have no effect on the rate of live-weight increase of swine in the Cambridge University herd, and the basis on which animals are allotted to groups to ensure homogeneity is fallacious.

SUMMARY AND CONCLUSIONSThe results of experiments conducted on 156 swine, from time of weaning till bacon weights were reached, are reported. One hundred and twenty of these animals were subjected to complete dietary control as regards the quantity of food consumed and the composition of the diet.Twenty-nine treatments, consisting of different amounts of Ca, P and vitamin D added to an otherwise adequate diet, were imposed.The reaction of the animals to the treatments was studied in relation to growth (increase in weight), appetite, utilisation of the food, the blood picture (concentration of serum Ca, blood inorganic phosphate, serum phosphatase and blood Hb), and the morphology and chemical composition of the bone. The results obtained are summarised in Table XVIII.

No abstract

A description is given of a peculiar condition which developed in certain animals being fed rations at present in use for the nutrition of swine in this country.The experimental treatments which were being imposed at the time bore no relation to the onset of the symptoms which appeared to develop indiscriminately.The animals refused food, adopted a swaying or “drunken” gait, at a later stage lost the power of their limbs and finally became prostrate.