Wool sulfur concentration and output in fleeceweight-selected and control Romney rams

Abstract

Wool sulfur concentration and output of Romney sheep from fleeceweight-selected and control lines were measured with a view to determining their potential use as genetic markers for fleeceweight. Midside wool samples were collected at 28 day intervals from 4 to 14 months of age from 35 fleeceweight-selected and 30 control rams. Clean wool growth during each sampling period was calculated. Wool samples were digested using an open wet digestion method and the wool sulfur concentration was determined by plasma emission spectrometry. Fleeceweight-selected rams had significantly greater midside wool growth than the control animals throughout the trial except on day 56. Average wool sulfur concentration in both lines increased over the sampling period to a peak at day 308. The wool sulfur concentration of control rams was significantly higher than that of fleeceweight-selected rams only on days 28 and 280. Total sulfur output (the product of midside wool growth rate and sulfur concentration) was significantly higher in the fleeceweight-selected than in the control rams on days 84-140 (March-May) and 196-308 (June-October). It is concluded that midside wool sulfur concentration and output of 4 to 14 month-old-Romney hoggets are unlikely to be useful genetic markers for fleece production.

Responses to betaine and inorganic sulphur of sheep in growth performance and fibre growth

“…The greasy wool samples were washed using a standard procedure (Min et al., ). Then, the growth rates (Lee and Williams, ) and yields (Antram et al., ) of clean wool were calculated. Wool staple length (cm) was determined by measuring the length of 10 randomly chosen staples (ASTM, ).…”

Metabolic response of sheep skin to a chronic infusion of a variant of insulin-like growth factor I

“…Subsamples of wool (0.2 g) were weighed in the constanthumidity and -temperature room into flasks and digested using Br2 in carbon tetrachloride and CHNO3 [21]. Sulphur in the acid digests was determined by plasma emission spectrometry (model 34000; Applied Research Laboratories, Sunland, Los Angeles, CA, U.S.A.) operated as described previously [22].…”

“…In the six sheep allocated to LR3IGF-I treatment, one venous catheter failed to sample past the preinfusion period and so no metabolic measurements were made. The arterial catheters remained patent in all sheep for the 21 Each sheep was killed with an overdose of barbiturate (Pentobarb 500; South Island Chemicals, Christchurch, New Zealand) through the jugular catheter.…”