The influence of lactation on the quantity and quality of cashmere production

The aim of this study was to investigate the influence of lactation on cashmere production. Two groups of cashmere bearing goats, aged between 2 and 3 years, were used in this study. The control group included 12 non-lactating, non-pregnant subjects. The experimental group was made up of 12 goats that had given birth to twins or triplets and that had begun lactating in the second half of May. Lactation therefore had begun approximately 45 days prior to the beginning of the emergence of fibre on the body surface. Live weight was not affected by the physiological state under consideration. The decrease observed in January is too remote to have been an effect of lactation. One likely explanation is that after shearing the animals were obliged to use their body reserves for thermoregulation. Prolactin concentration was higher at the beginning of the study in both groups and it was not influenced by lactation. Albeit with a varied intensity, secondary follicles were found to be active during the entire trial period but activ- ity never reached 100% in either group. Lactation significantly suppressed the percentage of secondary follicle activity and this was more evident from June to September. Fibre length and diameter did not differ between the two groups, so lactation did not affect fibre dimensions. The period of growth was shorter in lactating goats (184 vs 226 d). This did not make a difference in fibre length in so much as the lactating goats manifested a higher daily aver- age growth rate (0.27 ± 0.03 vs 0.20 ± 0.03 mm/d; P lesser than 0.05) which compensated for the shorter period of growth. Lactation caused a decrease in productivity of an insignificant nature, therefore we hold that the negative effect of lactation on cashmere production does not depend upon the physiological status as such but, most probably, upon the level of productivity and the degree to which the lactation and fibre growth cycles overlap

Cashmere production from Scottish Cashmere kids and crossbreed Scottish Cashmere x Jonica kids

This study is part of a much wider research programme to evaluate the possibility of producing valuable textile fibres, such as cashmere, from goat breeds reared in Italy. In order to achieve this, we have used crossbreeding. The first stage of the programme consisted of evaluating cashmere production in F1 kids obtained by crossing white-haired Jonica does, which have no secondary fibres, with Scottish Cashmere bucks. The trial lasted one year starting in March 2007, and took place in the Department of Animal Production of the University of Bari (Italy). We used 14 male kids: 7 Scottish Cashmere (SC group), and 7 F1 (SC x J group) derived from crossing Scottish Cashmere bucks with does of the Jonica breed, commonly reared in southern Italy. All the parameters considered (live weight, number and active percentage of primary and secondary follicles, S/P ratio, patch weight, growth and length of guard hair and down, yield, down production and diameter, blood protein and T3 and T4) were significantly influenced (P<0.01) by age. Genotype also had a significant effect (P<0.01) on all parameters except for the active percentage of primary follicles and the blood protein level. The factors which influence down production showed the heterosis effect to a varying extent in F1, but they still produced significantly less than the SC group kids (38.5±4.04 vs 68.5±9.16 g; P<0.01). These results are largely due to both their low number of secondary follicles (30.0±1.46 vs 39.3±1.02; P<0.01), which also have a lower percentage of activity (64.7±2.47 vs 90.0±1.53; P<0.01), and also to the down length which was 28% shorter than in SC group. This genetic combination is clearly unsatisfactory so others must be sought, probably by using more rustic local breeds, as well as more productive breeds for crossbreeding

The influence of pregnancy and the beginning of lactation on pelage traits in cashmere goats

The aim of this study was to investigate the effect of pregnancy followed by the beginning of lactation on fibre traits incashmere goats. Two groups of cashmere-bearing goats aged between 2-3 years were used. The control group (A) included12 non-lactating, non-pregnant subjects. The experimental group (B) included 12 goats mated during the first weekof June, in order to have pregnancy and the beginning of lactation coincide with the period when cashmere normallygrows. As expected, Liveweight significantly varied in Group B during the last two months of pregnancy, when foetalgrowth reaches its maximum, and following delivery. Hair patch weight, because of the continuous growth of primary andsecondary fibres, increased significantly during the trial (P(Pvalues varied significantly (Ponly in November &ndash; December. Furthermore, this parameter also seems to be influenced by climatic factors and, in particular,environmental temperature, as shown by the negative correlation (r = - 0.28; Pgrowth rate and environmental temperature. Guard hair length and growth rate did not differ between the two groups,however, they were influenced by time. Cashmere yield and cashmere production were lower in group B (Pdifferences between groups were observed for cashmere diameter. Overall, pregnancy and the consequent period of lactationnegatively influenced cashmere rather than guard hair fibres. These negative effects were noted in quantitativeterms as yield and production dropped by 37% and 43%, respectively. We hypothesise that the complete overlap of pregnancyand lactation with the period of cashmere growth reduced the number of secondary active follicles and their degreeof activity and caused an increase in competition for the partitioning of nutrients between hair follicles and the graviduterus, first, and then the mammary gland, later