Sheep milk and its products are regaining popularity with approximately 15,000 sheep currently being milked in the UK. Extreme dairy type ewes such as the Friesland are expensive compared to commercial genotypes and the crossing of dairy type sires with commercial ewes to produce cross-bred daughters for milking offers an alternative route of entry into milking sheep. An investigation was carried out on a commercial unit in Aberdeenshire milking around 150 ewes to assess the relative suitability and performance of pure-bred and cross-bred dairy ewes under commercial conditions.

The study involved first lactation ewes, 5 Friesland x Scotch Halfbreds being compared with 5 pure-bred Frieslands. The ewes lambed at 15 months of age between 20 and 27 May and the ewes were grazed on ryegrass/white clover swards. Ewes nursed their lambs for four weeks after lambing and machine milking started on day 29 of lactation. Milk yield was recorded weekly while milk fat and protein were measured at two weekly intervals.

Consumer acceptability of lamb is ultimately determined by the eating quality of the meat. This paper reports on the eating quality evaluation of lean samples obtained from carcasses of crossbred lambs sired by Suffolk, Texel and Charollais rams.

The lambs used in this study were part of a larger experiment to compare the growth performance and carcass quality of lambs sired by rams of the Suffolk, Texel and Charollais breeds (Merrell, Webster and Ellis, 1990: BSAP Occasional Publication No. 14, pp. 169-172).

An upland flock of approximately 350 Mule (Bluefaced Leicester ♂ x Scottish Blackface ♀) was used to produce the lambs. Eight unrelated rams of each of the three sire breeds were mated to the ewes over two years (4 rams per breed per year). Their crossbred progeny were selected for slaughter when it was estimated that they would produce carcasses of Meat and Livestock Commission fat class 2 to 3L. All lambs had been multiple-born and reared as twins.

The use of ultra-sound scanning to estimate fat and muscle dimensions in live sheep is increasing in Britain. When used in the appropriate recording and genetic schemes these measurements, in conjunction with other information, can be used to estimate body composition in the live animal. Pollott and Guy (1992) have outlined the background and organisation of a sire-referencing scheme in the Suffolk breed, in Britain.

The use of BLUP techniques in this scheme requires the use of appropriate genetic parameters derived using the same model as that used for BLUP estimations. Computer programs utilising the Derivative-Free Restricted Maximum Likelihood (DFREML) technique with the individual animal model have recently become available for use with on-farm recorded data (Meyer, 1989,1991). Data from the Suffolk Sire-Referencing Scheme Ltd (SSRS) were analysed, using DFREML procedures, to estimate the genetic parameters of the lean meat estimators used in the scheme.

Taylor (1980) indicated the importance of mature size in the description of animals and its usefulness for standardising growth parameters. The mature size and body composition of the Gallego breed, a small meat-producing type first described by Mason (1967), have never been estimated under defined management conditions. Therefore, using the scaling rules and results of Thonney, Taylor, Murray and McClelland (1987) as a guide, a study was made to determine whether the reputation of Gallego lambs for producing lean carcases was borne out in the composition of mature animals.

Twenty-one ewes (mean liveweight, LW, 32.7, sd 5.4 kg) and eight rams (LW 47.6, sd 8.6 kg) were selected as cast animals on the basis of age ( >4 years), body condition score (BCS, >1.75), health and teeth status and group-fed on concentrate (180 g crude protein/ kg dry-matter) and hay ad libitum. LW was measured fortnightly. When all animals had a LW and BCS which were stable for 2 months, 3 subgroups were slaughtered monthly. Weights of wool, body organs and hot carcase (HC) were recorded. Dissection of the cold carcase (CC) into commercial joints (Cabrero Poveda, 1984) and total lean, bone and fat.

The Holstein and Belgian Blue double muscle type (BBDM) are two cattle breeds extremely different in extent of muscle proportion (Istasse, Van Eenaeme, Evrard, Gabriel, Baldwin, Maghuin-Rogister and Bienfait, 1990). In BBDM, the proportions of lean meat and fat are high and low respectively. Opposite trends are found in Holstein, the Belgian Blue dual purpose type (BBDP) being intermediate. This experiment was carried out to compare lipid metabolism in these 3 breeds.

Four bulls of these 3 breeds were used in a fattening trial. The initial weight was 340 kg. They were given a sugar beet pulp based diet supplemented with cereals, by-products and protein sources or vegetable origin. After a 145 days fattening period the final weight was 540 kg. Non esterified fatty acid (NEFA), triglycerides (TG) and cholesterol concentrations in the plasma were measured every 4 weeks during the fattening period. The plasma fatty acid composition was determined by gas chromatography. The 7, 8 and 9 ribs were removed at slaughter and cholesterol concentrations were measured in Longissimus Dorsi samples.

Previous studies in this area have tended to concentrate on the effects of short haulage distances on the behavioural patterns of bulls (Kenny and Tarrant, 1987) and the incidence of dark cutting beef following pre slaughter mixing (Price and Tennessen, 1981). To date, the current authors are unaware of any study which has been conducted to evaluate the effects of haulage distance and sex on the welfare of beef cattle and the eating quality of beef. As part of a much larger recording scheme such a study was conducted with 96 young continental cross beef bulls and 8 continental cross beef steers.

50 beef bulls and 8 beef steers from similar farms were subjected to a road journey of some 250 miles lasting about 480 minutes to an abattoir near Aberdeen. A further 46 beef bulls, which had originally come from similar farms to those outlined above, were subjected to an average road journey of 10 miles to the same abattoir, this journey lasting approximately 20 minutes.

The incidence of human coronary heart disease has been correlated with the serum cholesterol level and a high consumption of saturated fat. Furthermore the cholesterol level can be raised by shorter chain fatty acids (Rose, 1990). It was therefore interesting to compare breeds extreme in terms of fatness. The adipose tissue proportion of the Belgian Blue double muscled type (BBDM) is low while that in Holstein is high, the Belgian Blue dual purpose (BBDP) type being intermediate. The present experiment was designed to investigate how large difference in degree of fatness can be associated with differences in fatty acid composition.

Four bulls of the 3 breeds were used in a fattening trial. Their initial weight was 340 kg. Biopsy samples were taken from the Longitimus Dorsi (LD) at weeks 5 and 16 of the fattening period. They were slaughtered after 145 days. The 7-8-9 ribs and perirenal fat (PR) were removed at slaughter. Intramuscular (M) and intermuscular (IM) fats of the LD were obtained after dissection of the 7-8-9 ribs.

There has been substantial interest in the possible increased usage of the Duroc by the British pig industry. This followed several reports which indicated improved meat quality traits and advantages for Duroc cross females in sow productivity. An evaluation of productivity, carcase and meat quality traits of Duroc crosses was carried out as the second trial at the Stotfold Pig Development Unit.

Large White x Landrace, Duroc x Landrace and Duroc x Large White females were mated to either Large White, Duroc x Large White or Duroc males to produce slaughter generation pigs. Sibling same sex pairs of entire males, castrated males and females were reared on either ad libitum or restricted feeding regimens to slaughter weights targeted to produce carcases of 55 kg, 65 kg and 85 kg.

The fatty add profile of pig fat has profound effects upon both the eating and keeping quality of pig meat. Fatty adds within carcass fat may arise from two discrete sources, being de novo synthesis and direct deposition from fatty acids present In the diet. The relative contribution of these two routes, together with the fatty acid profile of dietary fat, will Influence the chemical composition of carcass fat. It is well established that diets containing high levels of unsaturated fatty acids will result in softer and oilier carcass fat and It Is often considered inappropriate to feed such diets during the finishing phase of pig growth. However the speed with which carcass fat reflects a change in dietary fat has not been quantified. The objective of the current trial was to measure the rate of change in fatty acid profile of carcass fat of finishing pigs following major changes in dietary fat.

If bovine spongiform encephalopathy were found to be transmitted vertically it might become necessary to remove the spinal cord intact from all beef carcasses. One way of achieving this would be to chine the carcass, thus avoiding contamination of the edible carcass with spinal cord during carcass splitting. In line with this possible development, this study examined whether hot chining would help to tenderise beef longissimus dorsi muscle through a tenderstretch effect. Ten beef animals were slaughtered, dressed and split in the conventional way. One side from each carcass was then chined at 50 min post slaughter and chilled overnight at 1 to 2°C.

Since the early 1980's there has been a growing interest in the Italian Piemontese breed as a crossing sire breed for use on dairy cows in the United Kingdom. Early interest was centred on ease of calving, growth performance and carcass yields but more recently there have been claims that the Piemontese breed produces meat which ranks highly for tenderness. The aim of this study was to evaluate carcass and meat qualities of Piemontese - sired cattle out of the British dairy herd by comparing these characteristics with similar and contemporaneous Charolais - sired cattle.

Several studies (Bryce Jones, 1964; Rhodes, 1970; Dransfield et al, 1984) have attempted to examine the comparative eating qualities of beef from entire male cattle with that from steers. In the past, most sensory evaluation studies have used specialised taste panels (Shearer Dunn, 1990) and/or objective measurements (Dransfield et al, 1984). Few have considered the preferences and opinions of the general public. A study was therefore conducted with 100 members of the general public to determine whether the quality parameters of texture, flavour and overall acceptability did in fact differ between bull and steer beef samples. A second aim of the experiment was to establish if any of the variability in personal preferences was related to the demographic factors tested. These were the respondents’ sex, age, area of residence and the frequency with which they consumed beef.

The Simmental is replacing the Hereford for crossng on dairy herds. To improve the productivity of the Hereford, bulls of the Canadian strain have been imported. The objectives of the present work were (1) to compare the growth and carcass composition of Friesian, Canadian Hereford x Friesian and Simmental x Friesian steers, and (2) to determine the effects of two levels of supplementary concentrates during finishing, and duration of the finishing period on carcass weight and composition.

In recent years there has been an increasing trend in the UK to develop low input (organic) systems for the production of agricultural commodities such as meat, milk and milk products, grains, vegetables and fruits. This trend is driven by a combination of consumer demand, environmental concerns and premium payments for such produce. There is also a consumer presumption that produce obtained ‘organically’ and animals reared under organic regimes are more natural and thus ‘better’ than products produced using more intensive systems. In the case of cattle there is evidence (Younie and Halliday, unpublished data) that animals grazed on ‘organic’ pasture perform less well and tend to be less healthy than their counterparts fed conventionally. To maintain ‘organic’ status essential micronutrients such as vitamins and minerals cannot be supplied from synthetic mineral and vitamin premixes. It is well documented that the fat soluble vitamins and their precursors are important factors in maintaining the nutritional and immune status of animals as well as the storage properties of meat. (Bendich, 1989, 1991, Ranken, 1989). The purpose of the work was to assess the fat soluble vitamin status of extensive and intensive pastures and the effect of grazing these on the blood levels in steers.

Straw (barley or wheat) is an important component of the diet of ruminants in developing countries but straw has a poor nutritive value due to the extensive lignification. The nutritive value of straw can be improved by several types of treatment (chemical, physical etc.). A number of workers have investigated different techniques of chemical treatment to improve the nutritional value and dry matter intake of straw (e.g. Homb, 1984, Rexan and Knudsen, 1984). Most of the workers have studied the nutritional improvement of treated straw in vitro but relatively few have investigated the potential of this feed, of improved nutritional value and high pH as a complement and buffer to acidic grass silage.This study was planned to investigate the optimum dietary inclusion level of alkali (NaOH) treated straw without affecting adversely animal performance and the economics of feeding.

Beef meat, in Belgium, is produced mainly from growing fattening bulls (38%) and culled cows from both dairy and beef breeds (38%). Meat from steers and veal calves is a smaller proportion (24%) of the total meat. Most of the beef meat is produced by specialized farmers in commercial units of large size with hundreds of animals slaughtered per year. The remaining production is done, at little scale, by some of the breeders. The success of beef production is associated with different factors such as genetic, housing conditions, diet and management. Nearly all the bulls which are slaughtered are from the Belgian Blue breed double muscled type. Belgian Blue is a breed of large size selected for meat production. The mam characteristics are high live weight gain, low feed conversion ratio, high dressing percentage and lean carcass (Hanset et al., 1989; Istasse et al., 1990).

Winter feed restriction of cows is a method frequently used to reduce production costs in spring calving suckler herds. In Ireland and the UK the main source of suckler dams is the dairy herd. Traditionlly, Hereford and Aberdeen Angus were the crosses most readily available from this source but supplies of Continental (Limousin, Charolais, Simmental) crosses have increased in recent years. This paper reports the effects of winter feeding level during the first four pregnancy/early lactation periods for Hereford x Friesian (HF) and Limousin x Friesian (LF) dams on performance of cows and their progeny.

The Piemontese breed is reputed to produce high quality carcasses, but its potential in U.K. beef production systems is unknown. Data from the United States on crossbred progeny (Cundiff et al., 1990) and from Italy on both pure breeds (La Carne Bovina, 1988) and crossbreds (Gigli et al., 1990) shown the Piemontese to be a light boned, low fat, high meat yield breed with a high dressing out proportion. Furthermore the meat quality data show that it produced the most tender meat of all breeds tested and this was achieved at a low marbling fat content. This trial compares the performance of Piemontese x Friesian and Charolais x Friesian steers and heifers when fed on an indoor silage beef system. The meat quality characteristics of the carcasses produced are reported elsewhere (Fisher et al., 1992).

Grass silage is a major constituent of the diet of ruminants but a reduction in voluntary feed intake has been observed by many workers (e.g. Osboum 1967, Taylor 1967) when compared with hay feeding. This reduction in feed intake is often accompenied by decreased production (e.g. live weight gain). The exact reasons for this reduction have not yet been confirmed but the low pH of silage is considered to be one of the many reasons because it prevents the animal eating large amounts of silage with problems. If animals are also getting concentrate with the silage, the situation may become worse as the animal has to face an enormous task of buffering so that blood pH can be maintained. Animals can produce saliva to buffer the low pH of silage and the acids produced by rumen fermentation. Thus feeds which stimulate saliva production such as straw, can help the animal (Webster 1988). Although straw is not highly digestible, due to lignification, after treatment with NaOH its digestibility can be improved and it could have a role in buffering acidic silage and the acid produced in the rumen, as well as stimulating saliva production. For this purpose a study was planned to investigate the use of straw (treated or untreated) in the diets of growing beef animals.

Previous studies have indicated that low body condition (LBC) at calving increases the duration of the postpartum anoestrous period in suckling beef cows (Henricks et al 1986; Wright et al 1987). The results of recent experiments also suggest that animals in LBC have a reduced incidence of LH pulses (Wright et al 1990) which is associated with a reduction in the incidence of large, oestrogenic, potentially ovulatory ovarian follicles (Prado et al 1990).

An experiment was designed to determine a) whether or not the normal process of follicular development can be accelerated in LBC cows by infusion of pulses of GnRH, so that their postpartum anoestrous period was as short as that of cows in HBC and b) the effect of GnRH pulse infusions on associated gonadotropin profiles.