A method is presented for predicting the genetic superiority of rainbow trout (Salmo gairdneri) selected by multistage selection for body mass at ten months of age. Trout selections are currently based on successive gradings for body width at 2, 4…
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…
A triticale/oat grain mixture (2: 1) was enriched with either a commercially available formula or a locally composed supplement in addition to different protein sources (urea, urea plus fish-meal, urea plus cottonseed oilcake, urea plus bitter lupins or bitter lupins…
Thermo-ammoniated maize residues supplemented with 1% urea (Diet 2) or 4.5% fish-meal (Diet 3) and untreated maize residues supplemented with 2% urea (Diet 1), were compared on an isonitrogenous base. The in vitro dry matter digestibility for Diets I, 2…
The chemical composition and in vitro dry matter digestibility of a number of forages, namely lucerne (Medicago sativa), Italian rye grass (Lolium multiflorum), triticale (Triticale hexaploide), oats (Avena sativa), tall fescue (Festuca arundinacea), babala (Penniseturn typhoides), forage sorghum (Sorghum bicolour…
The effect of exercising Merino rams on the lambing performance of 2 227 Merino ewes was investigated. The ewes were divided into three groups of which two were mated to exercised rams and the third to non-exercised rams. No significant…
One hundred and twenty Simmentaler and 120 Afrikaner cows were randomly divided into four herds of each breed. Supplements were compared in terms of cow and calf performance and costs. Either a rumen-stimulating lick (RSL), which contained approximately 26% crude…
Data of Dormer (n = 290) and SA Mutton Merino (n = 306) lambs, born by ewes which were observed continuously during lambing in 1989-1991, formed the basis of this investigation. Progeny of SA Mutton Merino ewes were heavier at…
Italian ryegrass was evaluated over four seasons at stocking rates (SR) of 20, 24, 28, 32 and 36 ewes with lambs/ha. During each of three seasons, between 19 and 24 ewes per SR were milked for 10 weeks, from three…
The mineral composition of poultry manure and litter from poultry enterprises throughout South Africa was determined. The manure contained high concentrations of macro and micro minerals. Ash content levels in more than 40% of the Breeder and Pullet litter and…
Twenty-four sets of full-sib ram lambs, each born from a different sire, were kept individually in pens and hand-reared from birth up to 50 kg live mass. Feed intake and mass of each lamb were determined every third day. Growth…
Data from purebred and crossbred cattle, consisting of the Hereford (H), Simmentaler (S) Afrikaner (A) breeds, were analysed to estimate breed additive effects, individual heterotic effects, breed maternal and average maternal heterotic effects. The traits studied were birth mass, weaning…
Records of the Elsenburg stud where the Dormer sheep breed originated in 1941, were analysed from 1941 to 1990 to investigate non-genetic factors contributing to early growth traits. The fixed effects, identified as having a significant (P < 0.01) effect…
Records of the Elsenburg stud where the Dormer sheep breed originated in 1941, were analysed from 1941 to 1990 to investigate non-genetic factors contributing to early growth traits. The fixed effects, identified as having a significant (P < 0.01) effect…
Data of the Elsenburg Dormer sheep stud which was kept closed since its inception, were collected over a period of 50 years (1941-1990). These data were analysed to monitor the increase in actual level of inbreeding and to investigate the…
Correlations were estimated from a total of 7740 lamb records, collected from 1943 to 1990, from the progeny of 215 sires of the registered Elsenburg Dormer sheep stud. Phenotypic correlations were generally positive and medium to high except for a…
Data from the Elsenburg Dormer sheep stud were used to estimate genetic and environmental change in early growth traits from 1943 to 1990. Best linear unbiased predictions (BLUP) of breeding values were obtained by Restricted Maximum Likelihood (REML) procedures fitting…
In an investigation of the subjective categorization of pelt traits in Karakul lambs it was demonstrated that the common practice of treating the categories of a trait as equally spaced intervals is invalid.
