The development of molecular biological techniques has created new possibilities for the selection and genetic improvement of livestock. The discovery of the PCR had a major impact on the research of eukaryotic genomes and contributed to the development and application…
Simulation modelling is an active part of animal nutrition which relies on mathematical functions to predict the performance of an animal. The Gompertz equation is one such function that is simple, but fits animal growth data well, and when used…
To test whether animals grown under ideal temperature conditions would have different growth parameters to animals grown in more conventional housing, sixty Large White x Landrace male pigs from three genotypes were housed in six temperature-controlled chambers. The results were…
The alkane method of measuring herbage intake in ruminants was compared with actual intake determined by transponder-controlled feed gates (Calan gates). Kikuyu (Pennisetum clandestinum) intakes of yearling bulls (Holstein-Friesland and Hereford) were measured for a period of seven days. No…
Damage to ostrich skins in the form of cuts and scratches obtained during growth result in lower quality skins that fetch lower prices. This represents a major financial loss to the ostrich industry. The stage at which such damage occurs…
The present study was carried out with the aim of determining the effects of storage temperature and storage position on embryonic mortalities of ostrich eggs. A total of 229 ostrich eggs was collected from two commercial ostrich farms. The effects…
Data were recorded for annual reproduction, wool traits and pre-joining live weight of between 992 (for staple strength) to approximately 1200 production records of Merino ewes over the period from 1997 to 2002. The resource population has been divergently selected…
The effect of divergent selection for ewe multiple-rearing ability over a 15-year period on mutton quality was examined on the M. longissimus dorsi and M. semimembranosus of entire rams (R) and ewes (E) derived from two Merino lines. The selection…
The aim of this study was to determine the chemical composition and digestibility of cowpea in poultry diets. Three cowpea cultivars, Glenda, Agrinawa and Indigenous were evaluated. The cultivars showed a wide range of protein contents (253.47 to 264.27 g/kg)…
Standard Lactation Curves were derived for South African Holstein and Jersey cows, using twenty herd -, eighteen age - and six season classes. Six herd classes were below and 13 above the average production level for both breeds. A standard…
A study was conducted to investigate the growth response to diet protein level of growing indigenous chicken between 14 and 21 weeks old. The chickens were offered diets ad libitum with 100, 120, 140, 160 and 180 g crude protein…
The aim of this experiment was to evaluate the efficacy of Neem seed extract (10% water solution) for tick control in goats in the Kilimanjaro area of Tanzania. Eighteen Small East African (SEA) and Toggenburg (TB) female goat kids between…
One thousand two hundred and fifty sexed day-old broiler chicks obtained from a commercial hatchery were randomly divided into five treatment groups of 250 birds each (negative control, antibiotic and essential oil combination at three levels). Each treatment group was…
Separate-sex rearing of slaughter ostriches was investigated as a management strategy to minimize skin damage. Day-old ostrich chicks were divided into three treatment groups; a group of mixed-gender and two single-sex groups, one male and one female. At three months…
Oviposition and egg quality traits were studied in dwarf and naked neck layers in Maputo (Mozambique), during a 28-d period at 35 weeks of age. Birds were caged individually in a laying house with natural light and ventilation. Average daylight…
A breeding policy to improve milk production in the Elsenburg Holstein-Friesland herd was adopted in 1984. Cow selection was based on partial (90 days) and completed (300 days) lactation records of 4% fat corrected milk and protein yields during first…
Grain samples were produced at 10 different locations in the Western Cape region of South Africa, on 2.1m x 6m experimental plots, over a period of 3 years. Twenty different cereal grain cultivars were used in the study. A randomised…
In order to study the embryo recovery rate using the transcervical technique in Saanen goats raised in the tropics, 20 donors were submitted to an oestrus synchronisation treatment using intravaginal progestagen sponges for 11 days. On the ninth day of…
The foliage of three Combretum species, C. apiculatum, C. molle and C. zeyheri, as well as that of Colophospermum mopane was collected over a period of two years. The chemical composition, in vitro organic matter digestibility (IVOMD) and the rumen…
The purpose of this article is to review the development of breeding objectives in beef cattle breeding and the derivation of economic values. There seems to be general consensus that definition of breeding objectives should be the primary step in…
