ABSTRACT The objective of this study was to investigate the effects of the method and dose of cyclophosphamide (CPA) administration on cashmere shedding. Thirty-two castrated Liaoning cashmere goats were randomly allotted to four groups, with eight replicates in each group. Goats in the four groups were injected intravenously or intramuscularly with CPA at doses of 20 or 25 mg kg−1 body weight (BW), respectively. Feed intake and BW were recorded, and erythrocyte count, hemoglobin content, and cashmere weight were determined. It was found that the CPA administration method had no significant effect on feed intake or BW of cashmere goats. Cyclophosphamide injection can significantly decrease the erythrocyte count and hemoglobin content of cashmere goats, but the effects are dependent on injection method and CPA dose. The injection method and dose did not significantly influence cashmere weight, but the method had significant effects on time to initiate shedding and regrown hair length. Regrown hair was longest by intramuscular injection with 20 mg kg−1 BW, which also caused the least erythema on the epidermis during the days after shedding. The results indicate that the CPA administration method can significantly influence cashmere shedding. Intramuscular injection of CPA at a dose of 20 mg kg−1 BW was found to be relatively beneficial for hair removal and regrowth in cashmere goats.

This study was conducted to investigate effects of inorganic and organic sulfur supplements on cashmere growth and their differences. Thirty-six six-month-old female Liaoning cashmere goats with a body weight of approximately 25 kg and good health were randomly assigned to three treatments: control, ZnSO4 and HMBi (2-hydroxy-4-(methylthio) butyric acid isopropyl ester). The three groups were fed a basal diet, a ZnSO4 diet (supplemented with 0.63% ZnSO4.H2O) and an HMBi diet (supplemented with 1.27% HMBi), respectively. Blood and cashmere samples were collected at the end of the three-month experimental period. The plasma concentrations of total protein, urea nitrogen, ammonia and amino acids; the cashmere content of amino acids and sulfur contents; the cashmere growth rates; and the diameter of the cashmere fibres were determined. The results indicated that dietary supplementation with ZnSO4 or HMBi can decrease the plasma urea nitrogen concentration and increase concentrations of total protein and methionine in plasma. In addition, the two types of sulfur supplements appeared to increase the methionine, cysteine and sulfur contents in cashmere fibres. Furthermore, the supplements can accelerate cashmere growth, with no significant effect on cashmere fineness. The promotion of cashmere growth probably stems from the improvement in the protein metabolic balance, sulfur retention and sulfur-containing amino acids synthesis in cashmere goats following the ZnSO4 or HMBi supplementation. In general, the ZnSO4 supplement promotes greater cashmere growth than the HMBi supplement under the experimental conditions.

The impact of dietary 2-hydroxy-4-(methylthio) butyric acid isopropyl ester (HMBi) on rumen fermentation in cashmere goats was investigated to determine the effect of this ester on cashmere production. Four healthy castrated Liaoning cashmere goats with permanent rumen cannulas were assayed for four periods. In each period, goats were fed a different diet: control diet (containing 0% MetaSmart (an HMBi product)), diet I (containing 0.85% MetaSmart), diet II (containing 1.27% MetaSmart) or diet III (containing 1.70% MetaSmart). Rumen pH, ammonia-N concentration, volatile fatty acid (VFA) concentrations and total protein concentration were determined after feeding in each period. Results showed that rumen pH significantly increased and rumen ammonia-N concentration significantly decreased when the diet was supplemented with 0.85%, 1.27% and 1.70% MetaSmart. Diets with 1.27% and 1.70% MetaSmart increased rumen total VFA concentration, and 3 hours post feeding all three HMBi diets increased acetic acid concentration. Rumen total protein concentration significantly increased in the goats fed 1.27% or 1.70% MetaSmart. Thus, diets supplemented with HMBi significantly affected rumen pH, ammonia-N concentration, VFA concentrations and total protein content. Dietary HMBi can promote rumen fermentation in cashmere goats.