• 1. Implementation of the EC meat hygiene standards (Proposal COM (89/673)) by the British abattoir industry post 1992 is likely to have a major impact on its structure. Against the background of low operating margins, many abattoirs are faced with the necessity of making substantial investment in order to conform with the standards.

• 2. The term ‘post 1992’ is used advisedly because there could be temporary derogations beyond the 1 January 1993 deadline. The possibility and current lack of definition of these is a major cause of uncertainty and anxiety over investment in the industry, and makes forecasts of industry structure difficult.

• 3. A survey was carried out during June to September 1990 to examine the projected future size and structure of the industry. Data were obtained from three sources:

• (a) a telephone survey to the managers of 80 non-EC approved abattoirs stratified by size and geographical region (carried out in August 1990),

• (b) a survey by MLC regional staff in close day-to-day contact with the industry (approximately 450 abattoirs), and

• (c) information obtained by MLC in the course of operating its Meat Plant Advisory Service (advice was provided to 150 abattoirs in 1989/90).

The data included a Judgement as to whether the abattoir would continue to operate post 1992 and an estimate of anticipated slaughtering capacity based on chiller capacity. Numbers of cattle, sheep and pigs slaughtered in each abattoir in Great Britain are available from MLC's levy records. The database is being updated regularly as new information becomes available.

Handling pigs with care before slaughter is beneficial for both animal welfare and meat quality. Water showering pigs in lalrage prior to slaughter is considered to calm pigs, improve meat quality and reduce slaughter line contamination (Logtestijn, Corstiaensen and Kruijf, 1977; Smulders, Romme, Kruijf, Eikelenboom and Corstiaensen, 1982). The objective of this experiment was to investigate whether water-spraying pigs, in the lairage of a commercial abattoir, reduced the amount of fighting and if it improved meat quality.

Meat quality forms an important part of the assessment of any production method. Some components of quality can only be assessed subjectively using sensory evaluation. Both consumer panels and trained panels have been used to assess visual appeal, tastes and odours, and each has its own advantages and disadvantages. Trained panels are better at discriminating and at describing differences between samples, but are less close to consumer reality. Because quality assessments are made from representative joints, differences among joints might add inconsistency to the results. However, comparisons between different types of panels or sampling sites have rarely been made and there is no indication how well they are associated. The present paper examines the results from different parts of the carcass and from consumer and trained panels assessing visual and taste characteristics.

Recent studies have shown that growing pigs can perform as well on diets containing up to 300 g/kg molassed sugar beet feed (SBF), (SBF substituted for cereals) as control pigs fed a conventional cereal-based diet (Bulman et al., 1989). SBF contains high levels of non-starch polysaccharides (NSP) but little or no starch. SBF NSP, unlike that of cereals, is almost totally fermented by growing pigs, the fermentation products being used to sustain growth to a similar extent as products obtained from the breakdown of cereals, when fed at levels up to 300 g/kg. The objective of this study was to determine the effect of feeding growing pigs diets containing increasing levels of NSP i.e. 0, 150, 300 or 450 g SBF/kg, on subsequent carcass and meat eating quality. The effects on meat flavour were of particular interest since reports have suggested that high levels of fermentation may result in high concentrations of skatole and tissues which would result in taint.

Greater demands have been imposed by present-day management practices on the modern dam with gilts being bred at younger ages and lower levels of back fat. This has raised questions over whether current rearing feeding practices and low pregnancy feeding regimes may have adverse influences on lifetime reproductive performance. The objectives of this experiment were to compare the reproductive performance of sows given different feeding regimes during rearing and pregnancy. Data previously reported from the experiment have shown that the weight and back fat depth of the gilt can be manipulated by feeding regime during rearing and pregnancy (Simmins et al. 1989). Sows reared on lower feed levels were more prolific in their first two litters but they also had longer farrowing intervals (Edwards et al. 1989). Further results up to the fourth parity are described here.

During lactation sows are often unable to consume sufficient feed to meet their metabolic needs and they must mobilise their body reserves to compensate for the nutrient deficit. It is generally recognised that this loss of body weight and body condition may influence subsequent reproductive performance but it is unclear what endocrine signals link the nutritional and reproductive states of the sow. The present experiments were, therefore, designed in an attempt to understand how changes in the nutritional and metabolic status of the sow during lactation influences post-weaning reproductive performance.

Previous work has shown that although the ovaries of multiparous sows are quiescent throughout lactation (McDonald, 1980; Edwards, 1982) there are episodes of oestrogen activity in the peripheral circulation which are both highly variable and at very high concentrations (Varley and Foxcroft, 1989). The suspicion is that the source of this oestrogen is the adrenal gland although it is also possible that body fat stores are capable of being involved in this. Any treatment causing adrenal regression should therefore reduce the incidence of oestrogen episodes in the peripheral circulation.

An experiment was therefore carried out at Leeds University to investigate the use of an orally active progestogen, allyl-trenbolone, which is routinely used in gilts and sows for the control of oestrous cycles, on the steroid hormone status and reproduction in multiparous sows.

Body reserves play an important role in reproduction because they can be used by the sow to buffer against inadequate nutrition when metabolic demands are high, especially in late pregnancy and lactation. There is, however, little available information on the dynamic role of body reserves during reproduction and the present experiments were designed to demonstrate how the body reserves of the sow change in response to different nutritional inputs and to determine whether these influence sow productivity.

Despite being very technically efficient the United Kingdom (UK) Pig Industry only supplies around 75% of the pig meat consumed in the UK. Exports are also low, being equivalent to H.5% of UK pig meat consumption. Vertical Integration can be defined as having control of a product through more than one stage of its production cycle. On the same basis Total Integration could be defined as complete control of a production process from the raw material to the product on the shop shelf. Vertical Integration, within the UK pig industry is seen as one way to achieve a marketing edge, especially as European markets open.

Genes from the Chinese Meishan pig have the potential to enhance reproductive performance of European pigs (Bidanel, 1989; Haley and Lee, 1990). In order to allow prediction of the impact of Meishan genes In a range of alternative improvement programmes all traits of economic importance must be evaluated and genetic crossbreeding effects estimated. This paper reports the results of a crossbreeding study of meat and carcass quality traits recorded at the last rib position.

Animals were purebred Meishan (MS) and Large White (LW) pigs, and reciprocal F1 crosses: Meishan ♂ x Large White ♀ (MS x LW) and Large White ♂ x Meishan ♀ (LW x MS). The animals were born In first and second parity litters at the Institute of Animal Physiology and Genetics Research, Edinburgh and performance tested at the University of Newcastle upon Tyne. The trial was performed in two replicates of equal size, each corresponding to a single parity, with a total of 273 animals. In both replicates, females and entire males of all four genotypes were tested (approximately equal numbers of each genotype and sex). Animals were housed indoors in like sex and genotype groups of six (three pairs of full sibs). Tests started at pen mean of approximately 35 kg of weight and ended at pen mean of approximately 70 kg. Animals were fed ad libitum on a commercial ration (195 g/kg crude protein, 13.2 MJ digestible energy/kg).

Long term selection experiments with laboratory animals can provide an excellent opportunity to examine the assumptions underlying the predictions in animal breeding because of their short generation interval and high reproduction rate. The infinitesimal model of many genes each with small effect is often assumed for the analysis of economic traits in livestock species which have been selected by breeders for different objectives. Under such assumptions the genetic variance is expected to be reduced in a predictable way due to selection (Bulmer effect) and inbreeding in a selection experiment. The Animal Model with a complete relationship matrix back to the base population accounts for these reductions in genetic variance due to inbreeding and selection and thus provides an unbiased estimate of genetic variance in the base population (Sorensen and Kennedy, 1984). Lean mass in selected lines of mice was analysed using the individual animal model, to test if the infinitesimal model assumptions hold in the selected lines for this trait

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.

There is currently much interest in overcoming the seasonality of sheep meat supplies in the UK and improving carcass quality. Towards that end, much research effort has been devoted to the development of techniques to induce early or out-of-season breeding in the ewe, but little attention has been paid to the male. Rams of most breeds show marked seasonal fluctuations In reproductive performance, with a depression in testis size, libido and semen quantity and quality during the spring and summer months and a period of high fertility in the autumn/winter, coinciding with the breeding season of ewes of the same breed. Problems of subfertllity which are frequently encountered following the use of various techniques to induce out-of-season breeding in the ewe may therefore be attributable, at least in part, to the ram. The choice of terminal sire for early lambing flocks is further compromised because some breeds of ram show later testicular recrudescence than others.

In comparison to steers, bulls have produced 10% higher liveweight gain, 14% higher carcase gain and 20% more lean in the carcase. Immunological castration, which is reversible may reduce aggressive behaviour and maintain the performance advantages of bulls. Active immunization against luteinising hormone releasing hormone (LHRH) reduces testosterone production and therefore aggression in bulls. However, a controlled, predictable response to vaccination has not been achieved. Consistent immunization may be possible using a monoclonal antibody against LHRH. An anti-LHRH monoclonal antibody was developed and studies were carried out to determine the binding characteristics of the antibody and the half-life when administered to 6 post-pubertal bulls. The ability of the antibody to neutralize the bioactivity of LHRH was investigated in bulls and mice.

It was postulated that the induction of twin ovulations in cattle may require a combination of two appropriate stimuli. The first putative requirement is an increase in the circulating FSH concentrations and/or a decrease in inhibin concentrations to induce the development of additional potentially ovulatory follicles. The second putative requirement is an increase in LH pulse frequency during the follicular phase of the cycle to enhance the stimulus for follicle maturation and ovulation. On the basis of studies reported in the literature, it was suggested that such stimuli may be provided by immunization against inhibin and against a steroid hormone such as androstenedione, respectively. This experiment was designed to determine the effects of immunization against androstenedione and inhibin, either separately or together on the endocrine status of heifers and on the associated patterns of ovarian follicle development and ovulation rate.

ß-adrenergic agonists are powerful repartitioning agents, increasing muscle protein accretion and reducing fat deposition in a variety of species. Their exact mode of action is not fully understood but some of their effects are similar to those elicited by exogenous growth hormone administration. Whilst there are few reports of plasma growth hormone (GH) concentrations being elevated in animals treated with ß-agonists, several in vitro studies have clearly demonstrated a direct stimulation of GH release from perifused or cultured pituitary or adenohypophyseal cells on administration of these agents. More recently, a brief, rapid rise in plasma GH has been demonstrated in rats infused intra-atrially with isoproterenol and this was sustained when the animals were pre-treated with somatotropin release inhibitory factor (somatostatin; SRIF) antiserum. This raises the possibility that ß-adrenergic agonists do stimulate GH release in vivo but that this response is rapidly counteracted by SRIF release.

The aim of this work was to attempt to enhance the repartitioning effect of ß-adrenergic agonists by immunizing young cattle against SRIF whilst administering cimaterol.

Animal feed manufacturing involves the use of a variety of raw materials to produce complete diets. These diets are defined according to nutritional and technological specifications to meet the requirements of several animal species. Some raw materials, for example certain legume seeds, can satisfy these specifications only after some form of processing.

A large variety of processes - physical, chemical and/or biotechnological - is currently applied to cereals (Table 1).

Among physical treatments, grinding is the most comnon ; it does not modify the chemical characteristics of the grains but improves the accessibility of the enzymes of the gut to their substrates by disrupting endosperm and aleuron cell walls. Thus, milling exposes the interior parts of the grain to the digestive enzymes. Some physical processing of barley grain, such as rolling, is necessary to give optimum digestion of the nutrients by cattle (ORSKOV, 1976). This treatment, applied to barley, appears to be beneficial for young species (KREFT and BOYLES, 1989). Pigs eat whole or very coarsely milled grain reluctantly (MAXWELL et al., 1970) and utilize whole barley poorly (LAWRENCE, 1970). For this reason, barley grain is commonly milled before feeding. Grinding of maize using a roller mill does not modify average daily gain, feed intake, feed conversion and fattening time of pigs. However, sensory evaluation tests, meat from control pigs fed untreated maize is preferred to meat from pigs given rolled maize (ITOH et al., 1986). However, finely ground barley causes a strong increase in the frequency of oesophagogastric lesions whereas diets countaining coarsely ground barley or crushed oats caused few lesions. Balance trials on lamb indicate that whole maize have more digestible, metabolizable and net energy than ground maize (BONSEMBIANTEE et al., 1988).

Many tens of thousands of tonnes of manufactured feed are consumed by farm animals each year and yet the incidence of infectious diseases contracted from this source is extremely low.

The potential disease hazards include, in alphabetical order, anthrax, botulism, bovine spongiform encephalopathy, foot and mouth disease, listeriosis, Newcastle disease (pigeon paramyxovirus infection), salmonellosis, swine fever and swine vesidular disease. The control of each of these diseases involves a number of different procedures, including the appropriate handling and treatment of the feed, the use of suitable management techniques on the farm, the vaccination of susceptible stock and either the treatment or slaughter of infected animals, or those animals in contact with them.

Several of the diseases (foot and mouth disease, swine fever and swine vesicular disease) have been eradicated from the U.K. while others (anthrax and botulism) occur only infrequently. On the other hand, the presence of salmonellas in feed does constitute a continuing problem since, although organisms do not usually cause disease in animals consuming the feed, they may ultimately cause gastroenteritis in people who either handle or consume meat derived from the animals concerned.

Tannins are phenolic compounds which possess antinutritional properties. Studies to assess the effects of tannins have either used bean cultivars containing differing levels of tannins (Jansman, Huisman and van der Poel, 1989) or tannin extracts (Marquardt, Ward, Campbell and Cransfield, 1977). This experiment evaluated the effect of tannins on the utilization of dietary energy and nitrogen by broiler chicks using two lines of field beans which were isogenic except for tannin content. Chicks were used because of their sensitivity to nutritional changes in the diet.