Two terms characterise the carcass and meat: carcass quality and meat quality. The former describes the yield of meat and the ratio of lean to fat and the farmer is paid for it, more directly in pigs. Meat quality describes the appearance and taste of meat and although these also vary and are arguably more important to consumers than yield, the industry does not obviously recognise this variation in terms of price differentials. Reasons for this include the difficulty of deciding where in the production-processing chain quality variation is introduced and the lack of reliable, easily-used measuring systems.

Outdoor reared pigs are said to suffer from less of a growth check post weaning than their indoor reared counterparts, Payne et.al (2003). Zinc oxide (ZnO) is often used to reduce the incidence of post weaning scours and the use of sodium butyrate as an additive in weaner pig diets has been shown to improve some aspects of small intestine structure (Miller et.al, 2006). The purpose of this experiment was to investigate the effects of butyrate supplemented weaner diets with or without a ZnO background (3.1 or 0g/kg ZnO) upon gut structure immediately post weaning in both indoor and outdoor reared pigs. We hypothesised that piglets reared outside would have a more developed gut than indoor reared pigs when weaned at 4 weeks and that the presence of ZnO and butyrate would further enhance gut development.

Traditionally, in most dairy cattle breeding programmes genetic evaluation of dairy sires and cows has been primarily based on 305-day lactation yield. To provide 305-day lactation yields many partial lactations have to be extended by adjustment factors resulting in overestimation or underestimation of 305-day yields which in turn leads to biased prediction of breeding values. Over the past decade there has been a considerable interest in using monthly test day records instead of 305-day lactation yield to predict breeding values of dairy cattle as early as possible and also to increase genetic gain through reducing generation interval. The main objective of present research was to estimate the genetic correlations between 305-day and monthly test day milk yields in Iranian Holstein dairy heifers.

Since the 1970's, many studies have been performed to estimate ileal digesibility using different methods for digesta collection. The methods frequently applied for quantitative collection are re-entrant cannulation or ileorectal anastomosis (IRA). Methods involving the use of a marker include the post- valve “T” caecal (PVTC) and simple ileal “T” cannula. Recent studies showed that PVTC has a number of advantages over the simple “T” cannulation methods (van Leeuwen et al, 1991; McCracken et al, 1996). The present study afforded the opportunity to (1) compare the PVTC with the IRA method, (2) compare the use of Cr2O3 and TiO2 as indigestible markers (3) evaluate the PVTC method for quantitative collection of digesta, using a range of diets of different fibre content.

The PVTC experiment was performed in Belfast. Twelve pigs, approximately 20kg, fitted with post valve “T” caecal cannulae according to the procedure introduced by van Leeuwen et al(1991), were randomized to 4 diets based on wheat (W, 760 g wheat/kg), wheat/middlings (WM, 380g wheat, 380 g middlings/kg), wheat/bran (WB,380 g wheat, 380 g bran/kg) or recombined wheat (WR,570 g flour, 130 g middlings, 60 g bran/kg) using a four period cross-over design.

Previous work has suggested that dimensional data obtained from digital image analysis (DIA) has potential to predict the slaughter liveweights of finished beef cattle (Hyslop et al, 2008). Both farmers and cattle buyers may benefit from being able to select animals to meet slaughter specifications more accurately on-farm. The objective of the current study was to assess the feasibility of an on-farm DIA system to predict a number of characteristics in beef steers at slaughter.

Social facilitation occurs when one animal increases performance of a behaviour due to the presence of another animal engaged in that same behaviour. Gonyou et al. (1992) reported that pigs in adjoining pens ate simultaneously more often if the feeders were adjacent to the common wall. Feeders which allow pigs to see pigs in the adjacent pen increase feed consumption in short trials (Hutson, 1995). Although these studies reported some form of social facilitation, the studies were either too short to detect an improvement in productivity, or none resulted. The objectives of this study were to determine if social facilitation of eating between pens of pigs can best be achieved by allowing visual contact through the wall or the feeder, and if feed consumption can be increased over an extended period of time.

Livestock systems in hill and upland areas of the UK are characterised by extensive grazing, mainly by sheep and beef cattle. These areas also represent some of the most valued semi-natural habitats and landscapes in the country, with many areas being the subject to any number of a range of types of designation. This paper explores how, within upland systems, livestock can be integrated with their environment to achieve both agricultural and environmental objectives.

In grass silage-based beef production systems, sugar cane molasses, of which the major carbohydrate is sucrose, is frequently an economically attractive supplement. However, the efficiency of utilisation of molasses appears to decline relative to barley, at high levels of dietary inclusion (Drennan, 1985) which may reflect differences in rumen fermentation. The objectives of this study were to (i) compare rumen fermentation in steers offered grass silage and a range of levels of a starch or sugar-based supplement, and (ii) since molasses has a low crude protein concentration, to determine the influence of the source of protein in a molasses-based supplement formulated to supply the same amount of nitrogen as a barley/soyabean mixture.

Most protein systems include an estimation of the proportion of protein (nitrogen x 6.25) which is immediately soluble in the rumen. However, since the procedures employed generally involve mechanically washing samples in cold water the validity of these values have been questioned. The aim of the present experiment was to compare different solvents with rumen liquor for determining the proportion of soluble dry matter (DM) in grass and grass silage.

The adverse physical effects of atmospheric ammonia on stock (Charles and Payne, 1966; Wolfe et al. 1968) and stockpeople (Kirkhorn and Garry, 2000) have been documented, but broiler chickens’ perception of this aspect of their own welfare has not been fully investigated. Previous studies have demonstrated a delayed avoidance of high ammonia concentrations (Jones et al., 2000) but we could not categorically claim that this was a true aversion to ammonia since the birds may simply have expressed a preference for fresh air based on their previous experience. This experiment was designed to establish whether avoidance of ammonia in broiler chickens was an intrinsic aversion, independent of previous atmospheric experience.

Dry matter food intake (DMFI) and digestibility (DIG) of the forage are two important nutritional aspects contributing to lambs growth and subsequent meat production. However, there is a lack of literature describing their inheritance and their phenotypic correlations with production traits, e.g. ultrasonic muscle and fat depth and growth rate, in the grazing lamb. This study aimed to investigate and quantify these parameters for grazing lambs.

This study involved 90 male Texel-Oxford lambs in 1995 and 82 in 1996. The sires in 1996 were lambs in 1995, providing genetic links between these two generations. The lambs were split equally between two lines previously selected for increased or decreased carcass lean content. The lambs were born in a five week period in March-April each year, and they were reared on, and grazed, improved mixed- species pasture, typical of a Scottish upland farm.

Disease resistance is often cited as the major challenge facing animal geneticists, with much effort directed towards finding disease-resistance genes. The PrP gene controlling resistance of sheep to scrapie is such an example. To design effective breeding strategies utilising such genes, it is critical to understand the impact that these genes have upon disease transmission. For example, it has been shown that it is not necessary to make all animals genetically resistant in order to protect the population as a whole from epidemics (MacKenzie and Bishop, 1999). Additionally, concern is often voiced over the possibility of the pathogen co-evolving with the host, reducing the utility of the genes. By combining animal breeding and epidemiology theory, this study derives strategies for using disease resistance genes to control disease transmission, and considers the co-evolution risks with such strategies.

Mauricio et al.(1997) reported that faeces as an inoculum in the gas production produced similar results to rumen liquor in terms of total gas production and OM digestibility but a greater initial lag phase was observed. Where a mathematical description is to be used to develop the gas production profiles an accurate description of the lag phase (the period prior to degradation during which multiplication and attachment of the micro-organisms occur) must be obtained. For this to be achieved when a large number of samples are to be examined, measurement of gas production has to be achieved rapidly; this is possible using a semi-automated technique (Mauricio et al., 1998). This study evaluated the effect of recording gas production using a manual (syringe) technique, with a standard 3 h interval, and at 1h and 3 h intervals using a semi-automated system.

Calliandra calothyrsus is a promising tropical leguminous browse, native to South America, but now planted in most parts of the tropics and subtropics. It is a fast growing plant, rich in proteins and can do well on poor soils (NRC, 1983). Its high content of condensed tannins has however limited its use as a feed for ruminants. The chemical composition and degradability in vitro in a consecutive batch culture (CBC) system were studied.

Evidence suggests that rooting behaviour in growing pigs involves elements of both foraging for food (Day et al., 1995) and exploration (Wood-Gush and Beilharz, 1983). The objective of this experiment was to investigate the relationship between rooting behaviour and foraging in growing pigs. This involved assessing the affects of food rewards and feed restriction on the performance of rooting behaviour.

Previous studies have shown that including fish oil (FO) in the diet of beef cattle resulted in increased long chain C20n-3 PUFA (C20:5n-3 and C22:6n-3) in muscle resulting in a lower n-6:n-3 ratio (Scollan et al., 2005). Fish oil is considered to be a good inhibitor of biohydrogenation in the rumen, resulting in increased production of C18:1 trans-11 (Vaccenic acid), the precursor for conjugated linoleic acid (CLA cis-9, trans-11) in muscle. This study investigated the effects of incremental levels of FO in the diet on fatty acid metabolism in the rumen.

Zinc is an essential trace element necessary for the activity of numerous enzymes. Supplemental zinc is considered normal for ruminant livestock to ensure that requirements are met. Although zinc deficiency is not generally recognised in the UK, there is considerable evidence that this supplemental zinc is beneficial. The aim of this study was to investigate the effect of partially replacing zinc oxide with a zinc proteinate in the diet of ewes in late pregnancy and lactation on performance and health of ewes and lambs.

Lipids are commonly used in ruminant diets to increase the energy density of the ration and increasingly to manipulate the fatty acid (FA) composition of the final product (meat or milk). However, lipids may have negative effects on rumen function and in particular on the extent of carbohydrate digestion, which is accompanied by alterations in volatile fatty acid proportions, towards less acetate and more propionate. These alternations are more pronounced for lipids high in polyunsaturated fatty acids particularly linolenic acid (18:3n-3; found in linseed). However, there is some evidence to suggest that the opposite is true for longer chain C20 FAs, found in fish oil (Doreau and Chilliard, 1996). This experiment has examined the impact of lipid sources differing in their FA composition (saturated compared polyunsaturated FA) on digestion of nutrients in the rumen and small intestine.

Two-stage techniques Tilley & Terry (1963) for the estimation of digestibility have 3 main disadvantages for use in developing countries with limited laboratory facilities. Carbon dioxide is needed to saturate the buffers; a centrifuge is necessary to separate residues from solubilised materials; and the methods uses pepsin as a proteolytic agent. The aim of the present study was to eliminate these three requirements for the faecal liquor method ( Omed et al., 1989), by replacing bicarbonate with phosphate buffer (Marten & Barnes, 1980), pepsin with biological washing liquid, and centrifugation with sedimentation.

Cassava root meal is a fine powder from the manufacture of chips and/or starch. Their disposal increases otherwise environmental pollution and health hazards. Nevertheless, ruminants can be fed on cassava tuberous roots, foliage, peel and residue obtained after processing cassava including cassava meal. Evidence so far shows that cassava meal is good source of energy which, when fortified, promote positive and high performance in cattle, sheep and goats. Cassava meal contains high level of energy and has been used as readily fermentable energy in the rations. However, the lack of nitrogen supplied from cassava meal that it is important to include nitrogen sources to balance the energy-nitrogen supply for the microbial activities in the rumen. The objective of this experiment was developing the new products from cassava meal namely, CASMEREA (cassava meal + urea) or commonly name “starea” or “casarea”.