"Experientia docet" - Experience is the best teacher
Waarnemings oor die voorkoms van bronstigheid by Afrikaner en Jerseykoeie onder ekstensiewe toestande in Noord-Kaapland
Observations on the occurrence of oestrus in Africander and Jersey cattle under extensive conditions in the Northern Cape Data concerning the occurrence of oestrus in Africander and Jersey cattle under extensive conditions were obtained from a crossbreeding program at Vaalharts…
The flowpaths taken by ground supplements in the stomachs of sheep
The object of this experiment was to find out whether ground supplements could be conveyed to the abomasa of sheep via the reticular grooves. If ruminal fermentation could be avoided in this way, suitable supplements would be more efficiently utilized…
Growth and laying performance of medium-type pullets subjected to quantitative and qualitative food restriction
The growth rate of medium-type pullets was manipulated by various quantitative and qualitative food restriction treatments in order to ascertain which of these methods produced the most satisfactory economic results. The results were based on food intake during the growing…
The effects of three methods of food restriction on growth and subsequent laying performance
A total of 2 400 medium type pullets was used in an experiment to compare three methods of nutrient restriction from 2 to 20 weeks of age. The treatments consisted of the following: two quantitative food restriction treatments designed to…
Carcass amino acid composition and utilization of dietary amino acids by chickens
In an experiment involving the feeding of different protein sources to one-week old chickens, no statistically significant differences occurred in the amino acid content of the chicken carcasses despite considerable differences in body mass changes as a result of the…
Incorporation of DPW, urea and fish meal with varying molasses levels in cattle feedlot rations
With the increasing shortages and costs of conventional protein-rich feedstuffs such as oilcakes and fish meal, and with the ever increasing cost of yellow maize, it was decided to investigate alternative protein and energy sources for use in cattle feedlot…
The use of South African bred opaque-2 maize in pig growth diets
The purpose of this study was (1) to compare South African bred opaque-2 (or high lysine) maize with normal maize in pig diets that contain an equivalent sub-optimum protein percentage and (2) to determine the protein sparing effect of a…
Changes in plasma progesterone and LH concentrations during the progesterone synchronised oestrus in sheep
The effect of progesterone synchronisation on the plasma progesterone and luteinizing hormone (LH) concentrations in sheep were studied. During their normal breeding season 10 Merino ewes were injected with l0 mg progesterone daily for 15 days to synchronise their oestrous…
The effects of feed restriction, oestrogen priming and stage of the oestrous cycle on GN-RH- induced release of LH in ewes
The effect of underfeeding during autumn lactation, oestrogen priming and stage of the oestrous cycle on the release of LH in response to GnRH was studied in Merino ewes. The basal LH level prior to GnRH administration was not influenced…
Genetiese parameters van speeneienskappe by Afrikanerkalwers
The inheritance and interassociation of weaning traits of 1142 Afrikaner calves, the progeny of 27 sires, were studied over a period of 25 years. The estimates of heritability of the weaning traits were as follows: 0,184 ± 0.071 for birth…
A micro-radioimmunoassay for measurement of rat luteinizing hormone
A sensitive and reproducible double antibody radio-immunoassay for rat LH measurement, which requires at most 50 μl of serum or plasma per tube, is described for use with l25I and rabbit anti-rat LH serum. The assay has a sensitivity of…
Die tyd van ovulasie by Karakoelooie na sinchronisasie van die estrussiklus met behulp van Repromap-plus
The influence of medroxyprogresterone acetate impregnated intravaginal sponges and 300 IU pregnant mare serum (PMSG) , the latter injected at different times before sponge withdrawal, on the length of oestrus, the interval from sponge withdrawal to the commencement of oestrus…
The influence of breed, castration and age on muscle fibre type and diameter in Friesland and Afrikaner cattle
Bulls and steers from Afrikaner and Friesland cattle fed ad lib. were slaughtered at different ages from birth to 24 months inclusive. Samples were taken from the M. semimembranosus and M. semitendinosus (dark and light) and histochemically treated with succinic…
Die teeltstruktuur van die Suid-Afrikaanse Vleismerino
Samples consisting of 1 262 and 2 291 pedigrees were employed in the analysis of the breed structure of the S.A. Mutton Merino for l961/62 and 1971/72 respectively. The breed structure was not stabilised in either analysis since the first…
The chemical composition of milk from Afrikaner cows
The chemical composition of milk of Afrikaner cows kept under ranching conditions of feeding and management were determined. –The contents of non-casein and globulin nitrogen as well as phosphorus and calcium were statistically significantly influenced by age. Stage of lactation…
Minerals and nitrogen in poultry manure
Poultry manure, potentially suitable as a ruminant f'eedstuff, was obtained from various sources Samples consisted of pure excreta from birds kept in batteries, broiler excreta on deep litter systems and pullet and breeder excreta on deep litter systems. Large variations…
