"Experientia docet" - Experience is the best teacher
The use of trichloroacetic acid as precipitant for the determination of ‘true protein’ in animal feeds (Short Communications)
The suitability of trichloroacetic acid as a protein precipitant for the determination of 'true protein' in feed samples was investigated. The TCA method compared well with the cupric hydroxide method recommended by the Association of Official Agricultural Chemists.
Fenotipiese statistieke van produksiekenmerke by Angorabokke (Kort mededeling)
Phenotypic statistics of production traits of Angora goats. Measurements of 625 unselected 2-tooth Angora goat ewes in a commercial flock were analysed. The mean and standard deviation of body mass were 22,1 and 2,91 kg and of grease fleece mass…
Genetic parameter estimates for tick resistance in Bonsmara cattle
The objectives of the study were to estimate genetic parameters for tick resistance and to evaluate the effect of the level of tick infestation on the estimates of genetic parameters for South African Bonsmara cattle. Field data of repeated tick…
The effect of ammoniation by urea on the nutritive value of wheat straw for sheep
Straw is a major by-product of the grain industry. Indirect ammoniation by urea to improve the nutritive value of straw was investigated. Ammoniated and untreated wheat straw were compared in a 2 x 2 factorial experiment at CP levels of…
The metabolizable energy content of some South African feedingstuffs evaluated with poultry
Thirteen feed ingredients, representative of those used in the feeding of poultry and pigs in South Africa, were assayed for apparent and true metabolizable energy content (AME and TME), with at least 60 determinations being made on each ingredient. The…
Evaluering van verskillende kommersiële prosesseringsmetodes op die voedingswaarde van pluimvee-afvalmeel
Evaluation of different commercial processing methods on the nutritional value of poulty byproduct meal. Poultry byproduct meal consisting of 5 volumes of feathers, 2 volumes of offal and 1 volume of blood, was processed in three different ways and evaluated…
The effect of whole and halved intravaginal sponges combined with either subcutaneous or intravenous administration of PMSG on s
The oestrous cycles of Karakul ewes were synchronized during both the breeding (February) and non breeding season (October) using either whole or halved sponges, in combination with either subcutaneous or intravenous administration of PMSG. At the time of sponge withdrawal,…
Seasonal changes in sexual activity and semen quality in the Angora ram. 2. Semen volume, quality and freezability
Seasonal changes in semen volume and quality in the Angora ram were investigated. Semen was collected by means of an artificial vagina and criteria such as ejaculate volume, semen pH, sperm concentration, sperm motility, percentage live and normal sperm and…
Phenotypic and genetic aspects of production in the Dohne Merino. III The influence of age of the ewe on reproductive performanc
To determine the influence of age of ewe on reproductive performance and the age specific death rate in the Dohne Merino, data from 1 310 individual lambings accumulated between 1975 and 1980, were used. The reproductive performance of the Dohne…
Phenotypic and genetic aspects of production in the Dohne Merino. IV. The influence of age of the ewe on production traits
To determine the influence of the age of the ewe on characteristics such as body mass, greasy fleece mass, clean fleece mass, fibre diameter and staple length, the data obtained from 500 ewes born between 1970 and 1979 were used…
Stress and adaptation in beef heifers. 2. Influence of pen conditions on thyroid activity of Shorthorn, Afrikaner and Bonsmara h
Eighteen beef heifers, representing the Bos taurus (Shorthorn), Bos indicus (Afrikaner) and intermediate (Bonsmara) types, were confined to a pen with 4,6 m2 floor space per heifer. A similar number of heifers on veld grazing served as controls. Blood samples…
Production parameters of the impala, Aepyceros melampus
From a game farming point of view, the impala is quantitatively the most important animal in the Bushveld areas of South Africa. However very little published data are available on the productive capacity of this animal. In a long-term study…
The histology of the pre-natal follicle and hair fibre in four curl types of the Karakul sheep
In the Karakul sheep of Southern Africa four major pelt types can be identified, namely pipe curl, developed shallow curl, shallow curl and watersilk types. A study of the foetal skin was undertaken to determine whether histological differences do exist…
Ovine wet carcass syndrome of unknown aetiology
A condition of unknown aetiology, known as 'the wet sheep carcass syndrome' has led to the loss of about R500 000 as a result of the condemnation and trimming of carcasses, during the past 2 years. An affected carcass has…
Estimating phosphorus intake by grazing sheep
Estimating phosphorus intake in grazing sheep is difficult since hand-picked samples of forage do not represent actual intake. Results showed that faecal P did reflect dietary P levels. A minimum of 30 sheep should be sampled to obtain an error…
Effects of hot environments on bone growth in rats
The physio-chemistry and endocrinology of bone growth was studied in rats housed under different temperature conditions. Bone lengths did not change significantly but bone widths and densities became significantly smaller in rats kept at 34 °C.The depression of bone alkaline…
The effect of temperature on the ammoniation of wheat straw by urea
The aqueous ammoniation of wheat straw by urea, as affected by temperature and moisture level, was studied in a 4 x 2 x 6 factorial experiment. Treatments included temperatures of 4, 14, 24 and 35 °C, moisture levels of 250…
Urea-ensiled rice straw as a feed for cattle in Thailand
Rice-straw was ensiled with a 5-6% urea solution for 3 weeks before being fed. Cattle fed with urea-ensiled rice straw alone can maintain weight. However, to obtain a daily weight gain of 300-450 g in Holstein Friesian heifers (8-12 months…
