The recycling of urea to the rumen was studied in Merino ewes during different physiological states using radioactive tracers. The results showed that although the proportion of urea recycled differed, similar amounts were recycled in dry and pregnant sheep over…
Forty-five SA Mutton Merino ewes, 2 to 5 years of age, were divided into three groups. Although all ewes received the same basic diet, the diet of one group (group M) was supplemented with molybdenum and that of another group…
The effect of a copper deficiency on certain aspects of reproduction in ewes was investigated. An effective copper deficiency was induced by using the copper antagonists cadmium, calcium and sulphate. An average decline in the plasma copper concentration from 160…
Effect of intravaginal progestagens on oestrus activity of Mutton Merino ewes. Seven groups of SA Mutton Merino ewes, representing seven different stages in the oestrous cycle i.e., day 0 (ovulation), 2, 4, 6, 8, 10 and 12, were treated…
Concentrations of plasma copper and zinc as well as blood selenium were determined in single and twin lambs and their dams for a period of 120 days from the birth of the lambs, using Merino, Dohne Merino and SA Mutton…
Effect of nutrition and active immunization against androstenedione on reproduction of SA Mutton Merino ewes: Two groups of SA Mutton Merino ewes, consisting of forty ewes each, were used to determine the effect of nutritional level and immunization against…
Growth-related parameters, such as feed intake, growth rate and feed efficiency were investigated in ewe lambs of two genetically related synthetic lines and the Dorper. Ten ewe lambs in each of the three groups were individually fed in metabolism cages…
African Mutton Merino ewes as supplementary feed during late pregnancy and lactation, while grazing wheat stubble at 2 ewes/ha during 1986 and 1987. Blood glucose, urea, calcium, magnesium and zinc levels of the ewes were monitored in 1986 only. Ewes…
The objective of this study was to investigate the use of four different mathematical functions (Wood, Inverse Polynomial, Quadratic and Cubic models) for describing the lactation curve of unimproved Awassi ewes. Data were collected from 136 ewes from the same…
