The Angora goat herd in the UK primarily produces mohair but must, as an enterprise, maximise the return from animals that are surplus to requirement. It has been suggested that the Uk producer should be aiming for fourty percent of financial output from meat and sixty percent from mohair (Thirwell 1988). Compared to cattle and sheep, knowledge of yield and quality of goat meat reared under UK conditions is limited. The role of nutrition and stage of maturity in determining levels and distribution of fat are poorly understood (Warmington and Kirton 1990).

The male castrate Angora goat was selected since this constitutes the major source of meat, being generally redundant after two years of age when fibre quality begins to decline. Animals were sequentialy slaughtered at the predetermined ages of six,12, 18 and 24 months to coincide with the commercial practice of shearing Angora goats at six monthly intervals. Fourty animals, typical of those kept for commercial mohair production in the Uk, were reared under a commercial or intensive rearing system. Twenty goats were fed on a grass based, commercial system, representing that fovouring quality fibre production. The remaining twenty were reared intensively on an ad lib. pelleted complete diet containing 8.9 MJ/kg dry matter and 11.4 percent crude protein. Five goats from each diet were slaughtered at the predetermined times. After slaughter the carcases were jointed and then dissected inio lean, fat and bone. The quantity and composition of the intramuscular fat in the longissimus dorsi was determined using the Food and Research Association (1987) method and by use of gas chromatography.

Body composition changes in animals undergoing compensatory growth and these response vary with the age or stage of maturity at which the restriction is applied and with the undegradable protein in the diet during post-restriction period (O'Donovan, 1984; Ryan, 1990).

This experiment was conducted to determine the effect of level of intake during milk-fed period and the energy/protein relationship during post-weaning period on changes in carcass, non-carcass and empty body weigth (EBW) components in lambs slaughtered at 20 Kg live weigth (LW).

A total of 16 lambs of Churra breed were used in a comparative slaughter experiment to determinate the effect of level of intake during milk-fed period (4 weeks) and the protein supplement in the diet during post-weaning period on chemical body composition at 20 Kg LW

The lambs were assigned to a 2×2×4 factorial design, defined by 2 levels of milk intake (High: 1.5 MJ GE/Kg LW°75/day and Low: 0.9 MJ GE/kg LW°75/day) during milk-fed period, 2 post-weaning concentrate supplements (HP: barley grain plus 200g/kg fish meal and LP: barley) and 4 lambs per treatment.

All lambs were individually penned. During post-weaning period low quality hay and concentrate were independently offered ad libitum. Intake and LW were recorded daily and three times a week respectively. At slaughter (20Kg LW), EBW was estimated and carcass and non-carcass chemical composition (water, fat, ash and protein) and energy content was measured.

Female deer have a long productive life but there is little information available on what effect pattern of growth from weaning to puberty have on subsequent reproductive performance. The objective of this experiment was to investigate the effect of a high level of nutrition for hind calves during their first winter on their potential life time productivity.

Sixty red deer hind calves born in May/June 1991 were weaned in mid September and on 3 October 1991 the hind calves were weighed and randomised into two treatments:

1. Ad lib silage plus appropriate level of compound supplement, from 4-10 months of age, to achieve moderate growth rate, and a bodyweight of 75-80kg by 16 months of age (M).

2. Ad lib all-compound ration, from 4-10 months of age, to achieve high growth rates (H).

The hinds were housed in pens measuring 4m x 5m in a randomised block design with three pen replicates of 10 calves per treatment. Precision chopped high quality silage (ME=10.6) was fed ad libitum in swing-over troughs to treatment M. A supplementary compound ration of 125g whole barley and 75g soya bean meal per hind was fed until 23 December and subsequently increased to 32Sg barley and 75g soya bean meal per hind. The all-compound ration to treatment H consisted of 80% whole barley and 20% soya bean meal (ME=13.3) and was fed twice daily.

The botanical species composition achieved in sown swards is largely a result of plant factors such as capacity for growth of the component species, their competitive interaction and sward canopy structure interacting with the different diet selection patterns of the grazing animals. These interactions not only control the subsequent development of plant species and their contribution to overall sward composition but also affect animal outputs.

Sown swards offer a simple model to test hypotheses for understanding diet selection and foraging strategy of novel farm animal species like goats (Gordon and lllius, 1992). Their apparent selection against legumes in temperate grasslands (Clark et al., 1982), as compared to sheep, may offer opportunities for differential niche use by sheep and goats on grass/clover pastures. This could lead to increase clover contents in grass/clover swards and enhanced animal production. Previous field studies indicate that lambs in particular gain more live-weight when grazing swards with a higher clover content (Vipond et al., 1993).

The growing need to diversify animal agriculture in the UK has increased interest in the production of fibre and meat from goats. Previous studies (e.g. Shahjalal, Galbraith & Topps 1992, Anim. Prod. 541, 405–412; Deaville & Galbraith 1992, Anim. Fd. Sci. Technol. 38, 127–133) have suggested that protein supplementation can influence growth rate and fibre characteristics of Angora goats. The aim of the work reported here was to provide more detailed infirmation on the effect of level of protein supplementation on growth performance, carcass yield and fibre characteristics of British crossbred Cashmere goats.

Wool is the most neglected agricultural commodity in the UK. In many sheep enterprises the returns from wool represent less than 2% of the gross income and in some cases the value of the wool produced is less than the cost of shearing. Wool production, however, represents a potential avenue for agricultural diversification and, being a non-food commodity and suited to production in the Less Favoured Areas, accords with the agricultural policies of the UK government and the EU.

Significant increases in return from wool can come only from improvements in quantity and/or quality, two traits which in most breeds are negatively correlated. The most important determinant of wool quality, is fibre diameter. An analysis of prices of wools of different qualities over a four year period (1987-1990 inclusive) showed that the relationship between these variables could be described by the equation

There is a scarcity of information in the scientific literature on the effects of seasonal and nutritional factors on fibre production in the South American camelids. Without such information it is difficult to develop systems of management incorporating nutritional regimes and fibre harvesting strategies which will optimise the efficiency of fibre production. This paper presents preliminary results from an experiment designed to provide basic information on the effects of season and nutrition on fibre growth in llamas.

The experiment was conducted on 12 adult entire male llamas which were individually penned indoors under conditions of natural photoperiod and ambient temperature in north-east Scotland.

Two levels of nutrition were applied: the lower level (L) was calculated to supply approximately maintenance energy requirements (calculated as 0.44 MJ/kg0.75) and the higher level (H) to supply twice maintenance. The feeding comprised only hay for the L level and hay plus a proprietary cattle concentrate for the H level.

Angora and Cashmere goats produce two distinctive major fibres. The hair coat of the Angora goat consists essentially of a single fleece of Mohair grown by secondary hair follicles with a limited production of guard hair from primary follicles. The average fibre diameter ranges from 22 to 45 urn. In contrast, the Cashmere bearing goat has a double coat comprising coarse guard hair produced by primary follicles with the fine cashmere underhair (preferably 19 μm diameter or less) produced by secondary hair follicles. In the Angora goat, the fibres grow essentially continuously while in cashmere, hair follicle activity is determined largely by seasonal changes in photoperiod. The objective of this study was to investigate the effects of prolactin and melatonin, hormones implicated in the photoperiodic response, on the pattern of growth of secondary hair follicles isolated and maintained in vitro.

Hair fibre represents an important biological process to many feral and domesticated animals, both for environmental protection and as an aid to thermoregulation. Mohair which is the fine fibre produced by secondary hair follicles of the Angora goat grows essentially independent of season, with typical growth rates of 0.5-1 .0mm/day and annual yields typically 2-3kg. In contrast, down production from secondary hair follicles of double coated goats, classified as cashmere, is dependent on season. Fibre grows from around the summer to the winter solstice or later, with growth rates in this period of 0.3-0.7mm/day and annual yields maximally 600g but typically less than 100g. Questions arise as to how the seasonal stimuli affect fibre growth, and what determines the differences in fibre production between the two genotypes at the follicle level.

In the work described here, based on the in vitro isolation and culture technique developed for the Angora and Cashmere goats by Ibraheem et al (1993, 1992 repectively) we have compared fibre volume produced in vivo and in vitro, examined the DNA concentration and protein depositional capacities of mohair and cashmere secondary follicles. In addition the effects of the hormones prolactin and melatonin as mediators of photoperiod in vivo, on in vitro protein deposition in mohair and cashmere secondary hair follicles are also examined.

The sheep is a highly social animal and isolation from others members of the same species causes acute emotional stress (Kilgour & De Langen, 1970). Emotional or psychological stress rather than physical stress appears to activate the hypothalamo-pituitary-adrenal system (Mason, 1968). As part of a study of the effect of stress on reproduction, we have investigated the effect of temporary isolation of sheep on the release of β-endorpbin and concomitant secretion of LH. Previous reports have shown that isolation causes β-endorphin release from the pituitary (Matven, 1987 and Al-Gahtani & Rodway, 1991), but there is little information available on the effect of isolation stress on LH release. The purpose of this work was to examine the temporal relationship between β-endorphin release and LH secretion in sheep during isolation.

The effects of melatonin implants in advancing the breeding season and enhancing both ovulation rate (OR) and litter size in the ewe are well documented (Haresign et al., 1990; López and Inskeep, 1991). Likewise, oestrous activity and OR in the early breeding season can be stimulated by a moderately and constant body condition (BC) in Mediterranean sheep breeds (Forcada et al., 1992). However, little information is available in relation to the effect of nutritional status in ewes receiving exogenous melatonin on reproductive parameters. The present study was carried out to determine the effects of a constant BC throughout the year, and implant or reimplant of exogenous melatonin on onset of oestrous activity and OR in a reduced seasonality sheep breed.

The experiment was designed as a 2x2 factorial. Factors were two constant BC levels (≤2.50; L, and ≥2.75; H) and two forms of melatonin treatment (one implant -Melovine™- placed the 8th April; M, and a second implant 49 days later; 2M).

Surveys of flocks in the Near East have shown that lambing percentages of Awassi ewes are rarely above 85% and often as low as 65%. This is a major cause of the low output of sheep systems in the region. The low fertility results from a combination of poor nutrition, poor management, disease and possibly the effects of high temperatures at mating, which generally occurs in mid-summer.

Studies by Kassem et al (1989) and Thomson and Bahhady (1988) indicated that the reproductive performance of Awassi ewes is affected by body condition at mating. Neither of these studies was specifically designed to investigate the effects of weight or body condition and level of nutrition before mating on reproduction in Awassi ewes. The experiment reported here is the second in a series specifically designed to investigate the effects of body condition at mating, and level of nutrition before and after mating, on the fertility of Awassi ewes.

Factors influencing voluntary forage intake in ewes during the last two months of gestation are not sufficiently documented. The effects of hay quality and level of concentrate were studied by Orr and Treacher (1984) but other factors such as prolificacy or level of body reserves are poorly understood (Theriez et al., 1987). Furthermore most of the results come from animals kept in individual pens abolishing the effect of behavioural interactions. The purpose of the present experiment was to examine the effect of the number of gestated lambs and level of concentrate on voluntary intake of hay by ewes kept in a group.

A flock of 120 multiparous Manchega dairy ewes were synchronised using intravaginal progestagen and injected with 400 IU of PMSG (Chronogest, Intervet). After ultrasonic pregnancy diagnosis at 60 d after mating (Toshiba Sonolayer, Mod.Sad-32B, 5.0 MHz), two groups of 30 twin or single pregnant ewes were selected and distributed in a factorial design 2x2x3. Factors were number of foetus (S = l, T=2) and level of concentrate (H=600 g/d, L=300 g/d) with 3 replicates of 5 ewes each.

Open nucleus breeding systems have been shown to result in higher genetic gains and lower rates of inbreeding than closed systems. The organisation of an open nucleus system is, however, complex and the long term success depends upon a consistency of objectives among, and strong commitment from the participating breeders. Initial genetic differences between flocks ultimately result in a greater advantage of the open nucleus system, but the short term effect, for the better flocks, is a reduction in genetic gain compared to closed flock selection. The open nucleus system also involves the physical transfer of breeding stock between flocks, which may represent a risk to sheep health.

There are, at present, a number of sire referencing schemes operating in pedigree sheep populations. These schemes involve the mating of ‘reference’ sires to randomly nominated ewes in a number of flocks. The genetic links that are created between flocks enable accurate comparisons of estimated breeding values and therefore accurate selection across flocks.

Finished lamb production in the UK is based upon the use of terminal sire breeds, selected for carcass characteristics, mated to crossbred ewes, chosen for maternal attributes. Previous experiments have shown that even where good quality terminal sires were used too high a proportion of finished lambs produced carcasses of moderate quality (Merrell, Webster and Ellis 1990; Merrell 1993). Ultimately, an improvement in the carcass attributes of crossbred ewes should help to alleviate this problem. A long term experiment which aims to compare the performance of crossbred ewes bred from two crossing-sire breeds was set up in 1989. During the first phase of this experiment (1989 - 1992) selected ewe lambs were retained to produce the two crossbred ewe flocks, surplus ewe lambs and all wether (castrated male) lambs were finished. Data are presented for finished wether lambs produced during this initial phase.

Dicalcium phosphate accounts for 70% of the total costs of mineral mixtures in Brazil and studies have been made of the use of alternative supplementary phosphorus sources for ruminants (SILVA FILHO et al, 1992). The aim of this work was to evaluate monoammonium phosphate (MAP), triple superphosphate (TSP) and Tapira rock phosphate (TRP) as alternative P sources to the expensive dicalcium phosphate (DCP) by studying the kinetics of radiophosphorus (32P) in the blood of sheep given such supplements.