Angora Goats Research Articles

Polymorphism of bone morphogenetic protein 4 gene and its relationship with litter size of Jining Grey goats

Two pairs of primers (P1 and P2) were designed to detect single nucleotide polymorphisms of exon 2 and intron 2 of bone morphogenetic protein 4 (BMP4) gene in both high fecundity breed (Jining Grey goat) and low fecundity breeds (Boer, Angora and Inner Mongolia Cashmere goats) by single strand conformation polymorphism. Results showed that no polymorphism was detected for exon 2 (primer P1) of BMP4 gene in four goat breeds. For intron 2 (primer P2), three genotypes (AA, AB and BB) were detected in Jining Grey and Inner Mongolia Cashmere goats, two genotypes (AB and BB) in Angora goats, and only one genotype (AA) in Boer goats. Sequencing revealed one mutation (2203G>A) of BMP4 gene in the genotype BB in comparison to the genotype AA. The differences of litter size between AA, AB and BB genotypes were not significant (P > 0.05) in Jining Grey goats. A pair of primer (P3) was designed to detect polymorphism in the 3' flanking region of BMP4 gene that contained dinucleotide repeated sequence (CA) in the four goat breeds by microsatellite analysis. For primer P3, three genotypes (CC, CD and DD) were detected in four goat breeds. Sequencing revealed one more CA dinucleotide in genotype DD than in genotype CC. The Jining Grey does with genotype CC had 0.55 (P < 0.05) or 0.72 (P < 0.05) kids more than those with genotype CD or DD. These results preliminarily indicated that allele C of BMP4 gene is a potential DNA marker for improving litter size in goats.

Macroanatomy of the Cranial Cervical Ganglion in Angora Goat

The cranial cervical ganglia (CCG) in the heads of six adult (three male and three female) Angora goats were dissected in detail. The ganglion was located on the ventral aspect of the tympanic bulla, cranio- ventral to the atlas, medio-ventral to the jugular process and lateral to the longus capitis muscle. The branches of the ganglion were the internal and external carotid nerves, the jugular and laryngopharyngeal nerves and the connecting branches to the vagus and glossopharyngeal nerve. The internal carotid nerve arose as three branches (cranial, caudal and medial) from the cranial region of the ganglion. The cranial branch, the profound petrosal nerve, entered the pterygoid canal. The caudal branch terminated at the trigeminal ganglion. The medial branch terminated at the cavernous sinus. The other cranial branch ramifying from the cranial region of the ganglion was the jugular nerve. The internal carotid and laryngopharyngeal nerves arose from the caudal region of the ganglion. In conclusion, compared with published data on other species, we found differences in the number and courses of the branches ramifying from the CCG of Angora goats and in the branches connected to the vagus, glossopharyngeal and hypoglossal nerves.

Effects of Cholesterol on Progesterone Production by Goat Luteal Cell Subpopulations at Two Different Stages of the Luteal Phase

The aim of the present study was to evaluate the effects of cholesterol on progesterone production during long-term culturing of luteal cell subpopulations at early and late luteal stages of the goat corpora lutea. Corpora lutea were collected from Angora goats on days 5 and 15 of the oestrous cycle. Luteal cells were isolated by collagenase digestion. The cells were separated into two distinct subpopulations by Percoll density-gradient centrifugation. Both subpopulations of luteal cells staining positively for 3β-HSD activities (5 × 10(4) cell/well) were cultured with or without 22(R)-hydroxycholesterol (22R-HC) in serum-free culture medium for periods of up to 7 days. Cells were incubated with serum (10%) for the first 18 h of incubation followed by serum-free medium. Cell treatment (10 and 20 μg/ml) was performed on days 1, 3 and 5. Treatment of cells with both concentrations of 22R-HC resulted in significant (p < 0.01) and dose-dependent stimulation (p > 0.05) on progesterone production in both fractions of cells throughout 7 days of incubation. Treatment of the cells with cholesterol resulted in 2.5- and 9.0-fold increases in progesterone accumulation on day 3 of incubation. Steroid production was maintained throughout the incubations when cells are incubated in serum-free media treated with cholesterol and ITS premix. Cells collected from higher density of percoll layers produced 2.82 and 2.32 times more progesterone, in comparison to the lover density percoll layer, on days 5 and 15 of the oestrous cycle in untreated cell groups, respectively. Progesterone accumulation was decreased as incubation time advanced in all groups of untreated cells. These results demonstrated that goat luteal cell subpopulations secrete substantial amounts of progesterone in response to cholesterol treatment at least for 7 days, and cholesterol is required as progesterone precursor for maintaining a high-level steroidogenesis during long-life culturing of both cell subpopulations.

The Effect of Antioxidants on Post-Thawed Angora Goat (Capra hircus ancryrensis) Sperm Parameters, Lipid Peroxidation, and Antioxidant Activities.

The aim of this study was to determine the effects of the antioxidants curcumin, inositol and carnitine on microscopic seminal parameters, lipid peroxidation (LPO) and the antioxidant activities of sperm, following the freeze-thawing of Angora goat semen. Ejaculates were collected via artificial vagina from three Angora goats and microscopically evaluated and pooled at 37 ◦C. The pooled semen samples were diluted in a Tris-based extender, including curcumin (2.5, 5 or 10 mM), inositol (2.5, 5 or 10 mM), carnitine (2.5, 5 or 10 mM) and no antioxidant (control). The diluted semen was slowly (at a rate of 0.2–0.3 ◦ C/min) cooled to 5 ◦C and then cryopreserved in 0.25 mL French straws. Frozen straws were thawed indi

Effects of Hypotaurine, Cysteamine, and Aminoacids Solution on Post-Thaw Microscopic and Oxidative Stress Parameters of Angora Goat Semen.

Effects of Hypotaurine, Cysteamine, and Aminoacids Solution on Post-Thaw Microscopic and Oxidative Stress Parameters of Angora Goat Semen.

Effects of desertification on the body temperature, activity and water turnover of Angora goats

Globally, pastoral practices have transformed habitats, which often lead to desertification. With climate change predicted to exacerbate desertification, adaptation provides the best survival strategy for agriculturally important herbivores. We investigated body temperature, water turnover, physical activity and microclimate selection of Angora goats inhabiting transformed and intact sites in the Eastern Cape Province, South Africa. Although goats on both sites responded similarly under most environmental conditions, when goats were subjected to a thermal stress, imposed by shearing, those inhabiting the transformed site had a faster rate of rise in abdominal temperature (0.38 versus 0.31 °C h −1, P = 0.0009), displayed an increased 24-h abdominal temperature amplitude (1.8 versus 1.6 °C, P = 0.01) and were generally less active (3.9 versus 5.2 activity units) compared to goats inhabiting the intact site. Post-shearing, goats inhabiting the transformed site had higher water turnover rates ( P < 0.0001) and selected more variable microclimates ( P < 0.0001) than goats inhabiting the intact site, despite obtaining less water from their diet ( P = 0.01). Goats inhabiting the transformed site were more water dependent and more susceptible to thermal stresses in their environment than were those inhabiting the intact site. Coping with thermal challenges will be essential for Angora goats if the mohair industry is to thrive under future climate change scenarios.

Macroanatomy of the cranial cervical ganglion in Angora goats

The cranial cervical ganglia (CCG) in the heads of six adult (three male and three female) Angora goats were dissected in detail. The ganglion was located on the ventral aspect of the tympanic bulla, cranio-ventral to the atlas, medio-ventral to the jugular process and lateral to the longus capitis muscle. The branches of the ganglion were the internal and external carotid nerves, the jugular and laryngopharyngeal nerves and the connecting branches to the vagus and glossopharyngeal nerve. The internal carotid nerve arose as three branches (cranial, caudal and medial) from the cranial region of the ganglion. The cranial branch, the profound petrosal nerve, entered the pterygoid canal. The caudal branch terminated at the trigeminal ganglion. The medial branch terminated at the cavernous sinus. The other cranial branch ramifying from the cranial region of the ganglion was the jugular nerve. The internal carotid and laryngopharyngeal nerves arose from the caudal region of the ganglion. In conclusion, compared with published data on other species, we found differences in the number and courses of the branches ramifying from the CCG of Angora goats and in the branches connected to the vagus, glossopharyngeal and hypoglossal nerves.

A genetic linkage map for the South African Angora goat

Despite their economical importance, relatively few molecular studies have been made on goats compared to other livestock species. The most recent goat map was published in 1998, and lacks complete genome coverage. A large number of discrepancies and especially inter-chromosomal re-assignments were reported between the 1998 goat linkage map and the sheep map. In this study 94 microsatellite markers were amplified in 12 half-sib South African Angora goat families for compilation of a genetic map, aiming to confirm or reject previously reported rearrangements and to improve the alignment between the ovine and caprine maps. The number of informative meiosis per marker ranged from 69 to 836, with an average of 518. The microsatellites were mapped to 23 chromosomes, spanning 1352 cM and resulting in an average marker interval of 23.0 cM. Marker orders were compared to the previously published goat maps, as well as to the ovine map. Six chromosomes (CHI 2, 4, 5, 11, 13 and 19) showed rearrangements in marker order compared to the 1998 Schibler et al. goat map, while nine previously unmapped markers were conclusively assigned to eight chromosomes. Four of the previously reported intra-chromosomal rearrangements between the goat and sheep maps were confirmed to be either population specific or mapping errors. The verification of rearrangements in loci order will lead to improved alignment between the two maps, as well as improved efficiency of genome and fine mapping efforts in goats.

Model Selection in Estimation of Covariance Functions for Growth of Angora Goats

Covariance functions have been proposed as an alternative to model longitudinal data in animal breeding because of their various merits in comparison to the classical analytical methods. In practical estimation, different models and polynomial orders fitted can influence the estimates of covariance functions and thus genetic parameters. The objective of this study was to select model for estimation of covariance functions for body weights of Angora goats at 7 time points. Covariance functions were estimated by fitting 6 random regression models with birth year, birth month, sex, age of dam, birth type, and relative birth date as fixed effects. Random effects involved were direct and maternal additive genetic, and animal and maternal permanent environmental effects with different orders of fit. Selection of model and orders of fit were carried out by likelihood ratio test and 4 types of information criteria. The results showed that model with 6 orders of polynomial fit for direct additive genetic and animal permanent environmental effects and 4 and 5 orders for maternal genetic and permanent environmental effects, respectively, were preferable for estimation of covariance functions. Models with and without maternal effects influenced the estimates of covariance functions greatly. Maternal permanent environmental effect does not explain the variation of all permanent environments, well suggesting different sources of permanent environmental effects also has large influence on covariance function estimates.

Factors affecting pre-weaning kid mortality in South African Angora goats

The data used for this study were collected in 12 different Angora goat studs from 2000 to 2004. Data collected on 17534 kids born alive in the different studs were included in the analyses. Average pre-weaning mortality rate was 11.5% and ranged from 8.6% to 16.5% (of the 17534 kids born alive, 2018 kids died between birth and weaning at four months of age). Mortality rate in male kids was higher than that recorded for female kids (11.9% vs. 11.1%). When comparing the management systems followed from mating up until weaning in the different studs with the corresponding pre-weaning mortality rates, it is obvious that there was no discernible trend. Of the 2018 deaths recorded, the probable cause for only 601 (29.8%) deaths was known. The most important problems were predators, small, unthrifty kids who needed help with suckling, does having little or no milk and does abandoning their kids. When combining the latter three causes with udder problems (3.5%), 35.7% of pre-weaning mortalities was due to these causes. Birth weight and sex of the kid had a significant influence on pre-weaning mortality rate. Single-born kids had the lowest mortality rate (10%), followed by twin-born (13%) and triplet-born (22%) kids. Despite large differences in mortality rate recorded between sires within flocks, a heritability of 0.04 ± 0.01 was estimated for pre-weaning mortality rate. This low overall heritability could be attributed to the fact that causes of mortality differed considerably among kids and many of these causes may have no genetic background.Keywords: Rearing environment, reproduction, weaning, birth weight

Influence of body weight, age and management system on reproduction of South African Angora goat does

The effect of doe age, body weight and different management systems, as practiced in various Angora goat studs, on reproductive performance of does was investigated. The data used were collected from 2000 to 2004 on 12 Angora goat studs kept under different management systems. The data set analysed for this study contained data of 6271 does, each with a varying number of kidding opportunities. This amounted to 14644 doe records where each record included body weight before mating, body weight at scanning (ultrasound scanning for pregnancy diagnosis) and all reproductive performance data. There was a wide range pertaining to reproductive performance among the various studs. Apart from a high kid mortality rate, which is regarded by breeders as the most important factor contributing to low weaning percentages, nearly 20% of the does did not conceive or lost their foetuses before birth. Body weight of does before mating ranged from 13.0 kg to 59.6 kg (average = 34.6 kg) among animals, while body weight at scanning ranged from 18.0 kg to 67.0 kg (average = 38.6 kg). All reproductive parameters recorded had a typical inverted U-shaped relationship with age of dam, where the 2- and 3-year-old does and does older than 9 years of age fared significantly worse than the 4- to 9-year-old does. Management system had a significant influence on reproductive performance of does in the different studs. Higher reproductive rates were recorded under those management systems where additional or supplementary feeding at various stages of the reproductive cycle were supplied. Body weights before mating and at scanning had significant positive relationships with reproduction. For every kilogram increase in body weight before mating, 0.0237 and 0.0218 more kids will be born and weaned, respectively. Body weights before mating of young does that were kept on pastures until 18 months of age were higher than those of maiden does in the other management systems, resulting inhigher reproductive rates. Number of kids scanned, born and weaned per maiden doe at first kidding increased with an increase in body weight at first mating. From the results it is evident that body weight, age of the doe and management system all have a significant effect on the reproduction of Angora goats.Keywords: Nutrition, mating, pregnancy, kidding performance

Body Measurements, Growth, Quantity and Quality of Fleece in Angora Goat

Zeitschrift für Tierzüchtung und ZüchtungsbiologieVolume 61, Issue 2 p. 131-158 Body Measurements, Growth, Quantity and Quality of Fleece in Angora Goat K. Bilgemre, K. Bilgemre College of Agriculture, University of Ankara, Turkey, Zootechnical InstituteSearch for more papers by this author K. Bilgemre, K. Bilgemre College of Agriculture, University of Ankara, Turkey, Zootechnical InstituteSearch for more papers by this author First published: January‐December 1953 https://doi.org/10.1111/j.1439-0388.1953.tb00435.xCitations: 3AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Citing Literature Volume61, Issue2January‐December 1953Pages 131-158 RelatedInformation

Physiological limits to growth and the related effects on meat quality

Commercialisation of animal agriculture changed the phenotype and production characteristics of livestock. The sigmoidal growth curve and sequence of physiological events remained virtually unchanged, but the rate and extent of these processes increased remarkably. Physiological limits to growth are apparent in species selected for accelerated growth and production, like stress sensitivity, PSE and DFD syndromes in livestock, double-muscled cattle, the callipage gene in sheep, ascites and associated metabolic defects in broilers, leg problems in layers, abortions in Angora goats, wet carcass syndrome in sheep, and other tissue defects as well as reproductive failure due to interactions between the growth hormone cascade, gonadotrophic axis and endocrine factors that regulate metabolism like thyroxin and leptin. Although, the physiology of animals is generally quite forgiving, there are warning lights on the horizon. The challenge in livestock production should shift towards synchronising the best genotypes in a specific environment with the most appropriate and environmentally acceptable technologies available to produce consistently high quality meat. Manipulation of the quality of animal products through feeding, breeding and physiology will become increasingly important, provided that these technologies are practical, economical and do not detract from the intrinsic and extrinsic attributes of animal products, or any other aspect relating to environmentally acceptable or ethical livestock production.

Energy Expenditure and Activity of Different Types of Small Ruminants Grazing Varying Pastures in the Summer

Beker, A., Gipson, T.A., Puchala, R., Askar, A.R., Tesfai, K., Detweiler, G.D., Asmare, A. and Goetsch, A.L., 2009. Energy expenditure and activity of different types of small ruminants grazing varying pastures in the summer. J. Appl. Anim. Res., 37: 1–14. Objectives were to determine the activity energy cost for different types of goats as well as a breed of sheep and to evaluate methods of prediction. Eight animals each of yearling Angora, doeling goats, yearling Boer wether goats, yearling Spanish wether goats and Rambouillet wether sheep slightly more than 2 yr of age were used. Two animals of each type were randomly allocated to one of the four pastures 9.3, 12.3, 4.6 and 1.2 ha in area. Forage conditions varied markedly among pastures. The experiment was conducted in the summer with three periods, 30, 26 and 26 d in length. Energy expenditure (EE) was estimated from heart rate (HR) on pasture and EE:HR for each animal determined in a calorimetry system. A leg position/movement monitoring system and a GPS collar with position and movement sensors were used to estimate distance traveled and. time spent grazing/eating, resting while lying, resting while standing and walking without grazing/eating. EE attributable to activity (EEa%), expressed as a percentage of the ME requirement for maintenance plus activity in confinement, was determined based on total EE, BW and ADG. ADG was similar among animal types. Distance traveled was affected by an interaction (P<0.05) between animal type and period (Angora goats: 2.98, 2.33 and 2.47; Boer goats: 3.17, 3.46 and 2.68; Spanish goats: 2.85, 5.28 and 3.30; sheep: 3.04, 3.43 and 2.25 km in periods 1, 2 and 3, respectively (SE = 0.423). Time spent grazing was lowest among animal types (P<0.05) for Angora goats (4.3, 8.4, 7.8 and 6.8 h/day) and time spent walking without grazing was lower (P<0.05) for Angora goats and sheep than for Boer goats (1.7, 2.4, 2.1 and 1.2 h/day for Angora goats, Boer goats, Spanish goats and sheep, respectively). Total EE was affected by an interaction (P<0.05) between animal type and period (Angora, goats: 5.89, 5.55, and 5.16; Boer goats: 9.63, 10.92 and 8.55; Spanish goats: 6.73, 8.17 and 7.02; sheep: 12.54, 11.84 and 12.93 MJ/day in periods 1, 2, and 3, respectively (SE = 0.442). EEa% was affected by an interaction (P<0.05) between animal type and period (Angora goats: 15.7, 17.4 and 15.1; Boer goats: 59.7, 67.4 and 34.4; Spanish goats: 46.2, 61.7 and 41.6; sheep: 22.3, 11.8 and 21.9% in periods 1, 2 and 3, respectively (SE = 6.07). EEa% of goats was predicted with moderate accuracy (R2 = 0.40–0.41) and without bias from estimates of 5.79 and 5.05%/h spent grazing/eating and grazing/eating plus walking, respectively, determined in a companion experiment; however, these methods were not suitable for sheep.

Influence of stocking rate and mixed grazing of Angora goats and Merino sheep on animal and pasture production in southern Australia. 1. Botanical composition, sward characteristics and availability of components of annual temperate pastures

The effects of animal species (AS; Angora goats, Merino sheep or goats and sheep mixed grazed together at ratio 1 : 1) and stocking rate (SR; 7.5, 10 and 12.5 animals/ha) on the availability, botanical composition and sward characteristics of annual temperate pastures under continuous grazing were determined in a replicated experiment from 1981 to 1984. AS and SR had significant effects on pasture availability and composition and many AS × SR interactions were detected. The pastures grazed by sheep had significantly reduced content and proportion of subterranean clover and more undesirable grasses compared with those grazed by goats. There were no differences in dry matter availabilities between goat- and sheep-grazed pastures at 7.5/ha, but at 10 and 12.5/ha goat pastures had significantly increased availabilities of green grass, dead and green clover and less weeds compared with sheep pastures. There was a significant AS × SR interaction for the density of seedlings in May following pasture germination. Between July and January, the height of pastures was greater under goats than sheep but from January to March pasture height declined more on goat-grazed than on sheep-grazed pastures. There was an AS × SR interaction for incidence of bare ground. Increasing the SR increased bare ground in pastures grazed by sheep but no change occurred on pastures grazed by goats. Changes in pasture characteristics due to increased SR were minimised on pastures grazed by goats but the grazing of sheep caused larger and faster changes and the pastures were damaged at the highest SR. Goats did not always select the same herbage material as sheep, changed their selection between seasons and were not less selective than sheep. Angora goats were flexible grazers and continually adapted their grazing behaviour to changing herbage conditions. Goat grazing led to an increase in subterranean clover, an accumulation of dead herbage at the base of the sward, reduced bare ground, taller pastures in spring and a more stable botanical composition. Mixed-grazed pasture characteristics were altered with SR. With careful management Angora goats on sheep farms may be used to manipulate pasture composition, to speed up establishment of subterranean clover, to decrease soil erosion and to reduce weed invasion.

Influence of stocking rate and mixed grazing of Angora goats and Merino sheep on animal and pasture production in southern Australia. 3. Mohair and wool production and quality

The effects of animal species (AS; Angora goats, Merino sheep, mixed-grazed goats and sheep at the ratio of 1 : 1) and stocking rate (SR; 7.5, 10 and 12.5 animals/ha) on fibre production and quality were determined in a replicated experiment on improved annual temperate pastures in southern Australia from 1981 to 1984. Separately grazed sheep produced the most total clean fibre/ha at each SR. Mixed-grazed treatments produced amounts of clean fibre/ha similar to the arithmetic mean of sheep and goat treatments at 7.5/ha (21.9 versus 21.3 kg/ha), 10% more at 10/ha (28.3 versus 25.3 kg/ha, P &lt; 0.05) and 7% more at 12.5/ha (31.6 versus 29.6 kg/ha, P &lt; 0.10). Clean wool production/head was affected by AS and SR but not year. Clean mohair production was affected by SR and year but not AS. Variation in mean fibre diameter (MFD) accounted for 67 and 71%, respectively, of the variation in clean wool and clean mohair production/head. There was an AS × SR interaction for clean fibre production/t pasture. Growth rate of mohair was highest in autumn and least in summer. In each season, an increase in the SR reduced the clean mohair growth rate. Growth rate of wool was highest in spring and least in summer. Wool and mohair MFD were affected by an AS × SR interaction. Mohair MFD was also affected by year and season. At 10/ha, wool from mixed-grazed sheep had a greater MFD than wool from separately grazed sheep (20.2 versus 18.9 μm) and mixed-grazed goats grew mohair 1 μm coarser than separately grazed goats. At 12.5/ha mixed-grazed goats grew mohair 1.9 μm finer than separately grazed goats. Mohair MFD was predicted by a multiple regression that included average liveweight for the period of fleece growth, season of growth (summer 1 µm finer than winter) and year (range 1.27 µm). Mohair MFD increased 4.7 µm/10 kg increase in average fleece-free liveweight (P = 6.4 × 10–14). Fleece-free liveweight alone accounted for 76.4% of the variation in mohair MFD. There was an AS × SR interaction for the incidence of kemp and medullated fibres; under severe grazing pressure their incidence was suppressed. This experiment indicated that the principles associated with the effects of SR on wool production on annual temperate pastures apply to mohair production. Mixed grazing of Merino sheep and Angora goats produced complementary and competitive effects depending on the SR. Angora goats should not be grazed alone or mixed-grazed with sheep on annual temperate pastures at SR greater than that recommended for Merino sheep.

Influence of stocking rate and mixed grazing of Angora goats and Merino sheep on animal and pasture production in southern Australia. 2. Liveweight, body condition score, carcass yield and mortality

The effects of animal species (AS; Angora goats, Merino sheep, mixed-grazed goats and sheep at the ratio of 1 : 1) and stocking rate (SR; 7.5, 10 and 12.5 animals/ha) on the liveweight, body condition score, carcass yield and mortality of goats and sheep were determined in a replicated experiment on improved annual temperate pastures in southern Australia from 1981 to 1984. The pattern of liveweight change was similar for both species with growth from pasture germination in autumn until maturation in late spring followed by weight loss. In winter, sheep grew faster than goats (65 versus 10 g/day, P &lt; 0.05). In mixed-grazed treatments between November and December goats either grew when sheep were losing weight or goats lost less weight than sheep (P &lt; 0.01). Both AS (P &lt; 0.001) and SR (P &lt; 0.001) affected liveweight of sheep and an AS × SR interaction (P &lt; 0.05) affected liveweight of goats. Mixed-grazed sheep were heavier than separately grazed sheep at all SR with a mean difference at 10 and 12.5/ha of 4.6 kg. Mixed-grazed goats at 10/ha were heavier than separately grazed goats from the end of the second year of the experiment, but at 12.5/ha, separately grazed goats maintained an advantage over mixed-grazed goats, with a 9.4-kg mean difference in December (P &lt; 0.05). Body condition scores of goats and sheep declined with increasing SR; they were highest in late spring and were highly correlated with liveweight (r2 &gt; 0.8). Both AS and SR affected (P &lt; 0.001) carcass weight and GR tissue depth as a direct result of differences in liveweight. Adjusting for differences in carcass weight negated AS effects on GR tissue depth. The carcass weights of sheep and goats increased by similar amounts for each 1-kg increase in liveweight. Mortality of sheep (3.1% p.a.) was unaffected by AS or SR. An AS × SR interaction indicated mortality of separately grazed goats at 12.5/ha and mixed-grazed goats at 10 and 12.5/ha were higher (P &lt; 0.05) than all other goat (29 versus 9%) and sheep treatments, primarily because of increased susceptibility to cold stress. Disease prevalence differed between sheep and goats. Mixed grazing of Merino sheep and Angora goats produced complementary and competitive effects depending upon the SR. Goats used summer pasture better but winter pasture less well for liveweight gain than sheep. Angora goats should not be grazed alone or mixed grazed with sheep on annual temperate pastures at SR greater than that recommended for Merino sheep and the evidence indicates a lower SR will reduce risks associated with mortality.

Influence of grain supplements during winter on liveweight, mohair growth and mohair quality of weaner Angora goats

To identify methods to improve growth and mohair production of weaned Angora goats (mean liveweight 18–20 kg) during their first winter, two supplementary feeding experiments using whole-grain barley and lupins were conducted on a farm in southern New South Wales, in a region where weaner illthrift had been reported. Experiment 1 was a 2 × 2 + 1 factorial with 16 replicate goats; two feeding levels (115 or 230 g/day of whole-barley grain) × two periods of feeding (4 or 8 weeks) + Control (grazing only). Experiment 2 had five treatments × 13 replicate goats; three treatments fed 230 g/day of whole-barley grain for periods of 2 or 3 months and two treatments fed a 50 : 50 mixture of lupin and barley grain at 350 g/day for 2 or 4 months. Goats were individually fed and then all returned together for grazing. There were no effects of feeding in Experiment 1 and variations of feeding 230 g/day of barley in Experiment 2 provided no benefit. Feeding lupin/barley for 4 months increased liveweight (gain 59 g/day), mohair production, mohair fibre diameter and the incidence of medullated fibre. About 25% of this ration was not eaten by eight goats, reducing treatment average intake to 295 g/day. By the end of spring, there was no difference in treatment liveweights. Regression constants indicated that for each 1 μm increase in mean fibre diameter, greasy fleece weight increased 35 g and for each 1 kg increase in pre-shearing liveweight, greasy fleece weight increased 26 g. The results show that Angora weaner goats can grow during winter, provided their energy and protein needs for growth are met. Improved pasture management and higher levels of supplementary feeding to weaned Angoras are indicated compared with current practices on farms in Australia.

Genetics of fibre production and fleece characteristics in small ruminants, Angora rabbit and South American camelids

This paper reviews genetics of fibre production and fleece characteristics in small ruminants, Angora rabbit and South American camelids with a special distinction between single-coated (SC) and double-coated (DC) species. Considering the biology of fibre production, there are variations in coat composition and structure, fibre growth pattern and fibre structure and quality between these two main kinds of fibre-producing animals. In SC species, all fibres are nearly similar in dimensions and are produced from individual follicles that have a very long period, essentially permanent, of active growth without a synchronous phase of rest between follicles. In contrast, in DC species the fleece comprises a coarse outer coat and a fine inner coat with variations of coat composition and structure, and fibre growth pattern according to the season with a well-defined duration of fibre growth. Genetic basis of hair growth pattern, coat composition and fibre structure are different between species. In small ruminants, these coat characters are additive and because of several genes whereas in rabbit, several autosomal recessive genes determine fibre growth, coat composition and structure. In alpaca, the fleece type (Suri or Huacaya) is determined by a single dominant gene. This paper also reviews genetic parameters of fibre production traits in Angora goat, Angora rabbit and alpaca in which many aspects of the genetic basis of fibre production are analogous. There are many traits controlling both fibre quality and fibre quantity, and most of these traits tend to be moderately to strongly inherited so that a rapid genetic progress in any traits is possible and indeed has been achieved. However, there are differences in breeding programmes. In DC Angora rabbit, selection for one single trait, the easy measurable total fleece weight has general beneficial effects on fleece quality. However, because of antagonistic relations between qualitative and quantitative traits in SC species, achieving this goal requires a multi-trait selection index approach. Gene mapping studies have recently identified several putative quantitative trait loci and major genes affecting fibre and fleece characteristics in sheep, goat and rabbit are reviewed. The whole genome sequence of sheep and rabbit will be available in the near future and the use of high-density single nucleotide polymorphism chip will allow fine mapping and dissection of the genetic basis of many production traits including fibre production and fleece characteristics. The application of these techniques will thus contribute to improving the efficiency, profitability and sustainability of small ruminant and rabbit fibre production.

Fibre production by beef cows

Cattle grow and shed fibre which assists them adapt to seasonal changes in the environment. In the absence of cattle fibre production data for southern Australia, Angus, Hereford, Simmental and Limousin cows and crosses between these breeds grazing perennial pastures at Hamilton, Victoria were sampled in late winter. The fibre-growing area on the sides of cattle was measured, fibre sampled at the mid-side site and the sampling area determined. Fibre was tested for fibre diameter distribution, clean washing yield and fibre length measured. Cows were 3–7 years of age, liveweights were 412–712 kg and the mean fibre-growing area was 2.2 m2. This produced an average 682 g of total fibre (range 346–1175 g). The mean fibre diameter of all fibres was 51.7 µm (range 43–62 µm) and 18% of fibres were &lt;36 µm (range 6–39%). The clean washing yield was 92.4% (range 87.4–95.8%). Fibre length averaged 21 mm. Increasing the age, liveweight and condition score of cows and increasing weight of clean fibre were associated with significant increases in mean fibre diameter. Breed of cattle did not affect fibre production (P &gt; 0.1) but did affect mean fibre diameter (P &lt; 0.05). The quantity of fibre production indicates potential for low value textile production. The high level of total fibre production, twice that of an earlier report, and fibre shedding from cattle suggests that white fibre-producing animals such as Merino sheep, Angora and cashmere goats and alpaca should avoid using cattle-handling facilities, particularly in the month before shearing.