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…
A simplified method, whereby tick resistance in cattle is assessed by counting all ticks under the tail and on the scrotum or udder only, was compared to the Australian method, where tick resistance is assessed by counting successful females on…
An experiment was conducted to (i) determine the effect of heat treatment and thermal ammoniation on dry-matter digestibility and true metabolizable energy content of high-tannin grain sorghum in a digestion trial with roosters and (ii) to determine the relative nutritive…
In a chick growth assay over a 10-day period, no significant difference could be established between the effects of DL methionine, methyl maleic methionine and the methyl hydroxyl analogue of methionine on growth rate and efficiency of feed conversion. However,…
Sixty-two piglets weaned at three weeks of age were allotted, in pairs, to four experimental diets (14 piglets to one diet and 16 piglets to each of the other three diets), and fed until 10 weeks of age. The diets…
An experiment with 200 day-old male broiler chickens was conducted to investigate the effect of the dietary supplementation of turmeric rhizome powder (TRP) on plasma lipoprotein concentrations, and the meat quality and fatty acid composition of the thigh muscle of…
The relationship between beef bull libido and conception rate following a 21-day breeding period was investigated over two seasons. Libido was defined as the number of services completed during a 10-minute exposure to a restrained oestrous female. In the first…
Testicular development from 3 to 14 months of age was examined in Dorper (DD), Dohne Merino (DM) and crossbred (Meatmaster; MM) rams. Testicular measurements included testis volume (TV), diameter (TD), length (TL) and scrotal circumference (SC). Both TD and SC…
The repeatability of reproduction rate at 2 years or up to 3 years of age was investigated by regression methods considering subsequent reproduction averaged over a number of lambing opportunities or within subsequent age groups. Results from the study suggested…
Data of the Tygerhoek Merino flock were used to obtain estimates of genetic correlations of 18 months wool and pre-mating live mass traits with average reproduction over two to five lambing opportunities, as well as between pre-mating live mass and…
Data of the Tygerhoek Merino flock were used to obtain halfsib heritability estimates for the components of reproduction rate within age groups as well as averaged over a number of lambing opportunities. Two separate sets of data were considered. The…
The effects of energy and crude protein (CP) supplementation on feed intake of lactating ewes grazing native pasture (veld) were studied during two autumn (1981 and 1982) and two spring (1983 and 1984) lambing seasons. The CP content of the…
The effects of energy and crude protein (CP) supplementation on diurnal and seasonal variations in rumen pH and concentrations of ammonia (NH3) in lactating ewes grazing native pasture (veld) were studied during two autumn (1981 and 1982) and two spring…
The experiment was conducted to compare the mobile nylon bag technique (MNBT) with conventional digestibility techniques for the estimation of digestible energy (DE) in pig diets. Factors investigated were the effect of washing after retrieval, predigestion time, particle size, retention…
Two experiments were conducted to (i) determine the effect of thermal ammoniation (NH3BPS) and heat treatment (HBPS) of birdproof sorghum (BPS) on energy and N metabolism, measured with intact and ileo-rectal anastomosed pigs and (ii) to evaluate NH3BPS and untreated…
Five experiments were conducted to devise a feeding strategy to reduce fat deposition in broiler chickens. From these experiments it was determined that early feed restrictions, beginning at 7 days of age, decreased body fat, improved FCE, and had little…
Ovarian activity was studied in 36 dry, Bos taurus cows fed to achieve different rates of body mass loss and gain in a 2 x 2 factorial experiment. Cows were fed hay to supply either 70% (Treatments 1, 2) or…
Urea-supplemented wheat straw (UWS) was substituted stepwise by urea-ammoniated wheat straw (AWS) in diets fed to SA Mutton Merino ewes during late pregnancy and lactation. The experimental animals were fed ad libitum under zero grazing conditions over the last 8…
Problems relating to the anticipation and elimination of poor production due to mineral deficiencies in grazing livestock will be examined in this paper. Its concern is with subclinical problems rather than catastrophic clinical problems. The ways in which hypothetical models…
