Letteratura scientifica selezionata sul tema "Turretfield Research Centre"

South Australian medium-wool (M), non- Peppin medium-wool Booroola (B) and Peppin medium-wool Trangie Fertility (TF) Merino rams were joined to M ewes at Turretfield Research Centre, South Australia, in 2 years. Carcass composition was assessed in the ewe and wether progeny at 2 mean slaughter liveweights, viz. 24 and 38 kg. When adjusted to the same carcass weight, B x M had 13% more carcass chemical fat, 15% more subcutaneous fat, 6% less bone and the same lean tissue as M. The same result was observed for TF x M in relation to M in year 2. However, TF x M had more lean and the same amount of subcutaneous and chemical fat as M in year 1. Within the Booroola strain, there were no differences between offspring from 3 sires with genotype FF and the 1 sire with + + for any of 5 variables analysed. We conclude that crossing the Booroola with the South Australian Merino produces carcasses with the same amount of lean tissue, less bone and more fat when compared at the same carcass weight. The rank of TF x M with the other strains for the major carcass components remains obscure owing to a strain x year interaction.

Trichostrongyloid nematode infections of weaner sheep were investigated at the Turretfield and Minnipa Research Centres in the cereal zone of South Australia over a three-year period (1982-1985). Acquisition of nematode larvae from pasture occurred over a limited period each year, principally during the winter months, and coincided with the elimination of, or a reduction in the numbers of adult nematodes; sheep subsequently resisted challenge by infective larvae. Faecal egg counts were elevated during the summer, but declined to negligible levels during the winter months when larval challenge was at its maximum. Scouring, which was common in untreated sheep during winter at Turretfield, did not occur in regularly treated sheep, but no adverse effects were noted at Minnipa.

Trichostrongyloid nematode infections of weaner sheep were investigated at the Turretfield and Minnipa Research Centres in the cereal zone of South Australia over a three-year period (1982-1985). Acquisition of nematode larvae from pasture occurred over a limited period each year, principally during the winter months, and coincided with the elimination of, or a reduction in the numbers of adult nematodes; sheep subsequently resisted challenge by infective larvae. Faecal egg counts were elevated during the summer, but declined to negligible levels during the winter months when larval challenge was at its maximum. Scouring, which was common in untreated sheep during winter at Turretfield, did not occur in regularly treated sheep, but no adverse effects were noted at Minnipa.

Bibliography: leaves 325-341. Skin and fleece measurements were recorded at different ages for both male and female sheep from the Turretfield Merino Resource Flock and used to estimate the heritability of each trait and the phenotypic and genetic correlations among and between the skin and fleece traits. Generally, the heritability of each trait was high, which indicates that both the fleece and skin traits should respond well to selection.

Includes bibliographical references (leaves 325-341).
xxvii, 341 leaves : ill. ; 30 cm.
Skin and fleece measurements were recorded at different ages for both male and female sheep from the Turretfield Merino Resource Flock and used to estimate the heritability of each trait and the phenotypic and genetic correlations among and between the skin and fleece traits. Generally, the heritability of each trait was high, which indicates that both the fleece and skin traits should respond well to selection.
Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 2001