It has been suggested that female broiler chickens, having lower growth potential, are overprovided with dietary protein and that they will benefit more than males from a choice between a commercial standard food and whole wheat. The need for an initial learning period, before animals make ‘correct’ dietary choices has been emphasised (Mastika and Cumming, 1987; Rose and Kyriazakis, 1991; Shariatmadari and Forbes, 1991), but the problem of predicting the amount of necessary sampling, the method of learning and consequently the length of the experience period, or how often it has to be repeated, remained to be considered.

Therefore, the present experiment was designed to study whether birds need a learning period when presented with two foods, a commercial standard food (N) and whole wheat (W) in a choice feeding system.

Pigs are believed to posses a strong motivation to perform exploratory behaviour, which include a range of activities such as walking, orientation towards stimuli and direct investigation. Under free-ranging conditions these activities often occur in connection with foraging (Stolba and Wood-Gush, 1989). In ad libitum fed young growing pigs the provision of straw has been found to stimulate various behaviours involving direct investigation of the straw (e.g. Fraser et al., 1990; McKinnon et at., 1989). As it is assumed that growing pigs under such ad libitum conditions ingest sufficient nutrients, it is often assumed that the straw directed behaviour is unrelated to feeding motivation. However, individual pigs offered single diets may not be able to meet their nutritional requirements (Kyriazakis et al., 1990), and this may have behavioural consequences. For example, the straw directed behaviour observed in growing pigs may be a reflection of unfulfilled nutritional demands and in fact represent appetetive foraging. The aim of the present experiment was to assess the extent to which the exploratory activity of growing pigs is affected by limitations in nutrient intake (specifically the crude protein content of the food).

The current technique for artificial insemination (AI) of ewes during the breeding season necessitates the synchronisation of oestrus with progestagen sponges and PMSG, and involves depositing semen into the posterior cervix at a fixed time after sponge removal. Extensive field trials over a number of years in the UK have indicated that a single insemination using fresh diluted semen 56 h after sponge removal generally results in a conception rate of 70%, while conception rates following a single insemination of frozen-thawed semen 57 h after sponge removal have ranged from 19% to 34% (mean 28%). Giving two inseminations of frozen-thawed semen at 50 h and 60 h after sponge removal increased the overall mean conception rate, but only up to 48%. This inability to achieve acceptable conception rates with frozen-thawed semen nullifies many of the potential benefits of AI in sheep flocks.

It is well established that the cervix presents a major barrier to sperm transport in the ewe, particularly when oestrus has been synchronised with progestagens and PMSG.

Although there is some understanding of the effects of immediate levels of nutrition on ovulation rate and embryo wastage, it is not yet possible to predict the reproductive performance of ewes at pasture in the autumn. In many situations sward height declines over the pre- and post-mating period but herbage intake and reproductive performance under these circumstances have not been described. Furthermore, responses in reproductive performance to supplementary feeding at pasture in the autumn have been variable. It may he possible to explain some of this variation in terms of sward height and the substitution rate of herbage by the supplement. This paper reports 2 experiments which were conducted to describe (1) the herbage intake by ewes grazing swards at different heights and when supplements were offered, and (2) the reproductive performance of ewes given supplements as sward height declined.

The efficient production of lean beef suitable for current consumer demand necessitates effective rationing of beef cattle. Feeding standards for beef cattle given by ARC (1980) predict that a reduction in energy intake produces a large reduction in performance with little effect on the energy or fat contents of the gain. However previous studies have shown that diets containing a high proportion of grass silage may sustain lower levels of performance and result in a greater proportion of fat in the gain in both calves and finishing cattle, than when similar quantities of energy and protein are given in the form of high-concentrate diets. The effects of a change in energy intake on performance and carcass composition of beef cattle are therefore likely to depend on whether this change is achieved by restricting the quantity of food given or changing the forage: concentrate ratio of a diet given ad libitum.The present experiment was carried out to examine the effects of forage:concentrate ratio in the diet and ad libitum versus restricted dry matter intake on the performance, carcass composition and efficiency of lean meat production by steers.

A number of abnormal activities had been observed in a group of 30 lambs (R lambs; 10 Shetland (SH),10 Scottish Blackface (SB) and 10 Welsh Mountain (WM), half females and half entire males), on a restricted allowance (about mature maintenance intake and 0.5 of ad libitum intake), of a high quality pelleted diet (Diet A; 200g/kg crude protein, HMJ/kg ME). The lambs had been individually housed since 8 weeks of age, in pens (2m x lm), made up of metal barred gates with wooden slatted floors. Abnormal oral activities included some that caused obvious husbandry problems, such as wool-biting and slat chewing, and others which caused no overt damage, but may nevertheless be associated with impaired welfare (Cooper and Nicol 1993), such as bar-biting and repetitive licking. In a preliminary observation at 22 weeks of age, lambs only ate in the hour following food presentation (Fig 1), after which all of the allowance had been eaten, and abnormal oral activities were recorded in 30% of scans. Similar repetitive activities, described as “stereotypies” have been associated with food restriction in dry sows (Appleby and Lawrence 1987). In a series of observations, we investigated the effect of increasing weight and nutrient value of the lamb's diet on the incidence of oral stereotypies, whilst minimising any influence on the ongoing feed trial.

The primary aim of the calf rearer is to ensure a successful transition from non ruminant to ruminant status while achieving rapid growth and an early intake of solid food. Newbold, Blake and Hagges (1991), found that increasing the concentration of ME in either the starter or milk replacer will not promote more rapid growth, but will simply reduce the rate of starter consumption. This present study investigated the extent to which the energy density of a calf starter ration affected starter intake and liveweight gain in calves receiving a fixed allowance of a high energy milk replacer with ad libitum access to solid calf starter rations.

The indigenous sheep breeds of Greece, which are used mainly for milk production, produce lambs which are killed at weaning to provide carcasses (including the head, pluck, liver, spleen and the omental and mesenteric fat) of 5 to 9 Kg. The production of heavier carcases could be of benefit if they are acceptable to consumers and if they could be economically produced. The purpose of this experiment was to characterise the growth and development of the entire males and females of three Greek breeds under conditions presumed to be non-limiting.

Animals. From each of three breeds, Boutsiko (B), Serres (S) and Karagouniko (K), 20 lambs of each sex were used in a serial slaughter experiment. Four animals of each breed/sex combination were killed at live weights which were 25, 35, 50, 70 and 100% of the estimated mature values. All sheep were weaned at 6 weeks of age and the males were entire.

The continued genetic improvement for lean tissue growth rate and efficiency of pig production has allowed the liberal feeding of modern pigs without adverse effects on carcass quality or food conversion efficiency, even at heavy slaughter weights (Cole and Chadd, 1989; Webb, 1989). This genetic improvement has, however, been associated with a reduction in appetite so that the food intake of modern genotypes of pigs cannot be precisely assessed from the prediction equations established for the older and fatter genotype of pigs. The present experiment was designed to measure voluntary feed intake in order to facilitate the establishment of nutrient requirements and feeding strategies for modern pig genotypes.

Artificial drying is undoubtedly the most efficient method of grass conservation. The nutrient losses incurred in the drying process are low and, in contrast to other conservation techniques, grass drying is consistently efficient throughout the season and between seasons. However, both capital and running costs of a drying plant are high and inevitably the cost of production of dried grass is also high. Where there is a large proportion of small farms, as is the case in Northern Ireland, it appears to be out of the question for a farm unit to have a grass dryer because of costs. It is more than likely that under these conditions grass drying will be either undertaken on a cooperative or commercial basis, in the latter case the grass so used being a cash crop.

Previous experiments have shown important differences in milk production when mixed starch sources were replaced by mixed high quality by-products in high concentrate diets with hay as the forage (Sutton et al. 1987). The purpose of the present experiment was to compare rolled barley with sugar beet feed (SBF) in both molassed and unmolassed forms when given alone with grass silage in a high-concentrate diet. Additionally the effect of altering protein concentration of the concentrates was examined.

Nine local (indigenous) Zebu cows of average body weight 156 kg. were used to examine the performance in their first lactation given either fishmeal or wheat bran diets.

Fishmeal diet (A) consisted of 11.5 kg urea treated straw, 4 kg green grass and 0.25 kg of fishmeal. This diet contained an estimated 63 MJME, 518 g of rumen degradable protein (RDP) and 146 g of undegraded dietary protein (UDP). The wheat bran diet (B) consisted of 11.6 kg urea treated straw, 4 kg green grass and 0.5 kg wheat bran. This diet contained an estimated 66 MJME, 523 g of RDP and 91 g of UDP. Total dry matter intake of the two diets, A and B were 7.5 and 7.83 kg/d respectively. Therefore the two diets differed mainly in UDP levels. The composition and nutritive value of the ingredients of the two diets are given in Table 1 and 2.

The diets for growing-fattening bulls in Belgium are usually high in concentrate (Van Eenaeme, Istasse, Gabriel, Clinquart, Maghuin Register and Bienfait, 1990). The fat content of such diets in usually low at about 0.025. Over the recent years, feed manufacturers have incorporated fat in fattening diets. The incorporation rates are usually rather low so that the ether extract content is about 0.05 in fat supplemented regimes. At such rates upsets of intake and digestion and depression of growth could be avoided (Zinn, 1989). The fat concentrates which are incorporated are usually blends of various and very often unknown origins. Conflicting observations were reported on the effects of fat supplementation. Two experiments were carried out to assess the effects of soya oil on metabolism in the rumen and on apparent digestibility.

The technology to measure individual feed consumption of pigs in groups using electronic feeders is a recent development. As well as providing information on total feed consumption and consequently feed efficiency it is also possible to examine feeding behaviour under normal social conditions (ad libitum feeding in groups). Changes in feeding behaviour over a performance test are of particular interest to determine if growing pigs increase consumption by larger meals, more frequent feeding or a combination of both.

Selection for high lean growth rate may lead to changes in both feeding behaviour and duration of feeding which could have undesirable side effects in a genetic selection programme. Increased feeding activity may lead to aggression and lost efficiency of feed conversion due to greater activity.

A considerable amount is now known about the endocrine and neuro-endocrine control of parturition. Far less is understood however about the effect of events which may be considered stressful on the parturition process, despite its broad relevance to animal welfare and farm animal production. There is evidence that stress can have highly disruptive effects during parturition. For example, it has been suggested, that in pigs the behaviourally restricting farrowing crates used in commercial farming practice give rise to increased inter-piglet birth intervals and piglet mortality (Vestergaard and Hansen, 1984). Recent work on rodents has suggested that inhibtion of oxytocin secretion mediated by endogenous opioids, might be responsible for prolonged parturition following an acute stress such as a mid-partum change of environment. The aim of the present work was to extend the study of the effects of stress at parturition to a large animal model. We report two studies on the effects on parturition and oxytocin secretion of movement in mid-parturition to a novel environment (environmental disturbance). In Experiment 1 the effect of this disturbance on inter-piglet interval was investigated. In Experiment 2 a fuller investigation was made of the effects of environmental disturbance on a range of measures including inter-birth interval, behaviour of the sow and plasma oxytocin and Cortisol levels. The role of opioids was investigated in both experiments by administration of the opioid antagonist naloxone.

Glucosinolate levels are thought to be the major factor limiting the use of rapeseed meals in pig diets. The greatest differences In glucoslnolate content between samples of rapeseed appear to be attributable to variety and site of cultivation. A growing pig feeding trial was set up to Investigate varietal and site differences in the nutritive value of different rapeseed meals.

Rapeseed of the double low varieties Tapidor, Cobra, Libravo and Ariana were obtained from each of two sites (High Mowthorpe EHF, North Yorkshire and Bridgets EHF, Hampshire) where agronomic practices at both sites were very similar. These materials were solvent extracted to yield eight rapeseed meals of commercial type.

The utilization of diets high in fibre (defined here as non-starch polysaccharide - NSP) is dependent on the extent to which the NSP is fermented by the gut microflora, and the subsequent utilization by the animal of the end-products of fermentation - the VFAs. It has frequently been assumed that fermentation of NSP in the pig occurs almost exclusively in the hind-gut. However, a number of studies using pigs fitted with ileal-cannulas have suggested that some fermentation of NSP may occur prior to the hind-gut (e.g. Graham et al., 1985). The aim of this study was to determine the relative roles of the small and large intestine in a) the digestion of feeds containing non-starch polysaccharides, and b) the subsequent utilization of energy by growing pigs. This was achieved by comparing the abilities of intact or ileo-rectomised pigs to digest and grow on cereal-based diets containing 0 or 300 g/kg sugar beet pulp.

A breed improvement programme has been initiated at both ADAS Redesdale (Scottish Blackface) and ADAS Pwllpeiran (Welsh Mountain) to improve carcass conformation of hill ewes. From a base population of 1100 Welsh Mountain and 1600 Scottish Blackface ewes, nucleus flocks of 60 ewes have been established. Selection of ewes into the nucleus flock at each site has been based on their ability to consistently produce wether lambs crops with good conformation and above average carcass weights when selected for slaughter at a fat class 2/3L. The next objective is to replicate these ewes through multiple ovulation and embryo transfer (MOET) since theoretical studies (Smith, 1986) indicate that this can substantially increase the rates of genetic improvement through the female line. However, to date little work has been conducted to determine whether this technology can be successfully applied to hill sheep maintained in harsh hill environments in the UK, and this formed the basis of the current study.

Mating is one of the most critical processes influencing the success of any breeding pig enterprise since the efficiency of this process establishes the potential output of pigs. A study was conducted on 100 recently weaned sows during the mating process to determine potential sources of inefficiency.

The study was conducted in a large commercial herd with Large White (LW) x Landrace (LR) first cross sows. 4 genotypes of boar were in use, these being LW, LR, LW x LR and Duroc. The parity of the 100 sows involved in the study ranged from 1 to 9. Sows were housed in small groups of 5 to 6 following weaning at a mean of 18 days post partum and were taken daily to an oestrus detection area to test for standing oestrus (SO). Boars were housed around this area and SO was detected using the back pressure test Within 5 minutes of SO being confirmed, each sow was paired with a boar in a specialist 2.9 v 2.65 m mating pen. This pen had a 15 cm floor covering of sawdust-based deep litter which provided good foothold and comfort Boar-sow behavioural interactions, general behaviour of the mating partners and sow vocalisations were recorded from the first pairing in the pen to the dismounting of the boar following mating.

On hill farms where breeding cattle are kept there are advantages in retaining until the following spring at least a proportion of the surplus calves. The ability to winter them presents wider scope in choice of markets, while the sale of calves in spring, in addition to the dung produced, can provide a greater profit margin if wintering costs are minimised. Grass used efficiently in autumn offers an opportunity to reduce the requirement of the relatively expensive hay, silage, other crops and purchased feed. The value of extended grazing throughout autumn and winter months has been demonstrated by Smith (1953-4) for Blackface ewe hoggs, and for store stock and in-calf heifers by Hughes (1954) and Corbett (1954). In the case of calves, however, the period when late grass can be utilised depends on the continuance of moderate temperatures and availability of shelter from wind and rain, and therefore in most seasons will be relatively short. With these considerations in mind it was decided to compare the performance of two groups of weaned calves, one of which was housed and fed in courts immediately after weaning, while the other remained on grass for several weeks prior to court feeding.