• Asian-Australasian Journal of Animal Sciences
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• v.20 no.6
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• pp.821-826
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• 2007

The aim of the experiment was to detect polymorphisms in the keratin-associated protein 8.2 (KAP8.2) gene to determine associations between the genotype and fibre traits in Chinese Inner Mongolia cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Five hundred and forty-two animals were used to detect polymorphisms in the complete coding sequence of the hircine KAP8.2 gene by means of PCR-SSCP. The results identified six genotypes, AA, BB, DD, AB, AD and BD, coded for by three different alleles A, B and D. Two SNPs in the coding region were confirmed by sequencing, which were A214G and T218C respectively. The relationships between the genotypes and cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length were analyzed. There were significant differences (p<0.01) between the associations of the different genotypes with cashmere fibre diameter, cashmere weight and hair length. Cashmere length was the only trait that was not associated with the genotypes. The genotype AA (0.73) was found to be predominant in Inner Mongolia cashmere goats and the animals with this genotype had the thinnest cashmere fibre diameter compared with the other genotypes. These results suggested that polymorphisms in the hircine KAP8.2 gene may be a potential molecular marker for cashmere fibre diameter in cashmere goats.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.10
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• pp.1341-1347
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• 2011

The objective of this study was to investigate polymorphisms of keratin-associated protein 8.1 (KAP8.1) gene and its effect on fibre traits of Chinese Inner Mongolian Cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Five hundred and forty animals were used to detect polymorphisms in the complete coding sequence of the hircine KAP8.1 gene by means of PCR-SSCP. The results identified six genotypes, AA, BB, CC, AB, AC and BC, coded for by three different alleles A, B and C. Two SNPs in the coding region were confirmed by sequencing, which were T113G and G116C respectively. The relationships between the genotypes and cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length were analyzed. There were significant differences between the associations of the different genotypes with cashmere weight (p<0.01), cashmere length (p<0.05) and hair length (p<0.01). Cashmere fibre diameter was the only trait that was not associated with the genotypes. The animals of genotype AB and BB had the higher cashmere weight compared with the genotype AA. By further analysis, it appeared that the KAP8.1 genotype effects on fibre traits may be due to a mutation at the 113 locus. These results suggested that polymorphisms in the hircine KAP8.1 gene might be a potential molecular marker for cashmere weight in Cashmere goats.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.11
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• pp.1515-1520
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• 2012

Insulin-like growth factor binding protein-3 (IGFBP-3) gene is important for regulation of growth and development in mammals. The present investigation was carried out to study DNA polymorphism by PCR-RFLP of IGFBP-3 gene and its effect on fibre traits of Chinese Inner Mongolian cashmere goats. The fibre traits data investigated were cashmere fibre diameter, combed cashmere weight, cashmere fibre length and guard hair length. Four hundred and forty-four animals were used to detect polymorphisms in the hircine IGFBP-3 gene. A 316-bp fragment of the IGFBP-3 gene in exon 2 was amplified and digested with HaeIII restriction enzyme. Three patterns of restriction fragments were observed in the populations. The frequency of AA, AB and BB genotypes was 0.58, 0.33 and 0.09 respectively. The allelic frequency of the A and B allele was 0.75 and 0.25 respectively. Nucleotide sequencing revealed a C>G transition in the exon 2 region of the IGFBP-3 gene resulting in R158G change which caused the polymorphism. Least squares analysis revealed a significant effect of genotypes on cashmere weight (p<0.0001), cashmere fibre length (p<0.001) and hair length (p<0.05) of the animals. The effect of genotypes on cashmere fibre diameter was not statistically significant (p>0.05). The animals of AB and BB genotypes showed higher cashmere weight, cashmere fibre length and hair length than the animals possessing AA genotype. These results suggested that polymorphisms in the hircine IGFBP-3 gene might be a potential molecular marker for cashmere weight in cashmere goats.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.10
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• pp.1291-1298
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• 2010

The aim of this research was to investigate the dynamic changes of the level of total prolactin receptor (PRLR) mRNA and the short form prolactin receptor (S-PRLR) mRNA in skin of cashmere goats from the initiation of cashmere fibre growth to active growth. Eighteen half-sib wethers were allocated randomly to two groups. Melatonin implants were used in order to initiate growth of cashmere fibre before the normal time and reduce blood plasma prolactin (PRL) concentration. Real-time reverse transcription quantitative polymerase chain reaction (real-time PCR) was used to determine PRLR mRNA expression levels of skin from June to November. The results showed that, in Chinese Inner Mongolia cashmere goats, there were seasonal variations in expression of total PRLR mRNA in skin with levels decreasing from June to October. Synchronously, the cashmere fibre growth rate gradually increased during this period, but the expression levels of S-PRLR mRNA did not decrease along with seasonal variation from initiation to active growth of cashmere fibre. These results suggest that expression levels of S- PRLR mRNA might be involved in the process of cashmere growth. It was also possible that the change of alternative splicing of PRLR occurred in the skin of cashmere goats from proanagen to anagen.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.10
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• pp.1496-1502
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• 2007

The roles of melatonin in the control of deiodinase (MD) activity in cashmere goat skin and associated cashmere fibre growth were investigated. Eighteen half-sib Chinese Inner Mongolia cashmere wethers were allocated randomly to two groups (n = 9/group). One group was implanted subcutaneously with melatonin (2 mg/kg BW) at three 2-monthly intervals while the other group served as a control. All goats were maintained under natural photoperiodic conditions and were grazed on natural pasture. The plasma melatonin concentration showed a significant difference (p<0.01) between the implant group (M) and the control group (C) but plasma $T_4$ (or $T_3$) showed no significant difference (p>0.05). The monodeiodinase type II (MDII) activity in skin tended to increase gradually from the summer solstice to November. During July and August, the activity of MDII for the M group was higher (p<0.05) than that of the C group; also during this period, there was a significant positive correlation between MDII activity of skin and cashmere fibre growth rate. The monodeiodinase type III (MDIII) activity and the ratio of MDIII and MDII tended to decrease from the summer solstice to November. The ratio of MDIII and MDII for the M group was lower (p<0.05) than that of the C group in July and August. The cashmere fibre growth rate of the M group was significantly greater than that of the C group in July (p<0.01), August (p<0.001) and September (p<0.05). The cashmere fibre diameter and guard hair and body weight were not influenced (p>0.05) by melatonin implantation. The results demonstrate that melatonin plays an important role in the regulation of skin MD activity. Simultaneously, the cashmere fibre elongation stimulated by melatonin may result from enhanced MDII activity during a period of two months after melatonin treatment.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.12
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• pp.1843-1848
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• 2007

Thirty-six 1.5 year-old Inner Mongolian White Cashmere wether goats (body weight $28.14{\pm}1.33$ kg) were used to determine the effects of dietary copper (Cu) concentration on ruminal fermentation, nutrient digestibility and cashmere fibre characteristics. Wethers were fed a basal diet (containing 7.46 mg Cu/kg DM) that was supplemented with either 0 (control), 10, 20 or 30 mg Cu/kg DM. To ensure full consumption, animals were fed restrictedly with 0.75 kg feed (DM) in two equal allotments per day. The results indicated that: (1) supplemental 10 mg Cu/kg DM in the basal diet significantly (p<0.05) decreased ruminal fluid pH value and total VFA concentrations were significantly (p<0.05) increased on all Cu treatment groups. (2) Cu supplementation had no influence on DM intake and digestibility of DM, CP and ADF (p>0.05); however, NDF digestibility of groups supplemented with 10 and 20 mg Cu/kg DM were significantly higher than that of the control group (p<0.05). Apparent absorption and retention of copper were decreased with increasing level of supplementation. (3) 20 mg Cu/kg DM treatment significantly (p<0.05) improved cashmere growth rate, but cashmere diameter was not affected by Cu supplementation (p>0.05). In conclusion, supplementation of cashmere goats with Cu at the rate of 10 to 20 mg/kg DM in the basal diet resulted in some changed rumen fermentation and was beneficial for NDF digestibility, while supplementation of 20 mg Cu/kg DM improved cashmere growth. Collectively, the optimal supplemental Cu level for cashmere goats during the fibre growing period was 20 mg/kg DM (a total dietary Cu level of 27.46 mg/kg DM).