There they travel long distances upstream until they reach clear and cool breeding grounds. Some individuals, however, never head to the sea. Instead, they remain in their natal streams and mature sexually at young ages and at small sizes. Such individuals are called parr and they never go ...
On both forages sheep continuously selected leaf in preference to stem where this was physically possible. Within both leaf and stem fractions of the plants selection was for material of the highest available nitrogen content. This resulted in the sheep presenting themselves each day with material ...
Weaning, or the shift of a lamb’s diet from mother’s milk to solid food, can occur at any time between the ages of five and fourteen weeks. Lambs can remain with their mothers until they are around five months old. They are known as weaners during this period, and they begin eating...
Sheep and goats of all ages may be affected although disease is typically more severe in young and/or immunologically naïve animals. An epizootic in a susceptible flock of sheep can affect over 75% of the animals, with mortality as high as 50%; case-fatality rates in young and/or ...
High numbers of IgM-, IgG- and IgA-PFC were observed when B cells and educated T cells were transferred to the recipients. Evidence is provided that B cells committed to IgA synthesis require the same degree of interaction with T cells as B cells committed to IgM synthesis, but a lower ...
Heritability, genetic and phenotypic correlations were estimated using paternal half-sib analysis for body weight at various ages and average daily gain (ADG) for different growth periods. The overall least squares mean of body weights recorded for birth weight (BW), weaning weight (WW), six ...
In OVX lambs in the permissive sequence of photoperiods (long days of 16L:8D until 18 weeks of age, followed by short days of 8L:16D), LH pulse frequency was low in the presence of estradiol early in life at 9 weeks of age, but increased at later ages. LH pulse frequency in the...
use of shelter and selection of lambing sites by shorn and jjnshorn ewes in paddocks with closely or widely spaced shelters In addition, of the shorn and unshorn sheep that lambed away from shelter in these paddocks, some 50% more than expected on the basis of even distribution lambed ...
The analysis of differentially expressed genes in muscle tissues of sheep at different ages is helpful to analyze the gene expression trends during muscle development. In this study, the longissimus dorsi muscle of pure breeding Hu sheep (H), Suffolk sheep and Hu sheep hybrid F1 generation (SH)...
the lamb developed into an important model in which to test theories based on work in other species because it has a largeblood volumeand a pubertal hiatus of 6–7months that allowed for experimental manipulations at various ages prior to puberty. The first of these to be directly tested in...