The trend of increasing cow numbers per husbandry person makes it difficult to achieve good reproductive management by traditional means. A system to predict the reproductive status of cows would be of great value. There exist time-series models for detecting oestrus from milk traits other than progesterone and decision strategies for interpreting progesterone measures have been suggested but a system combining these aspects to predict not just oestrus but reproductive status throughout the reproductive cycle is lacking. The objective of this study was to develop such a model on the basis of automated milk progesterone sampling.

Relative to purebreeding, crossbreeding in the hill flock has been shown to increase lamb growth rates from birth to weaning by up to 12% and weight of lamb weaned by up to 24%, depending on ewe and ram breeds concerned (Carson et al 2001). Traditionally crossbred females produced in the hill are sold to the lowland as replacement females, so that potential hybrid vigour effects associated with crossbreeds are not fully exploited in the hill environment. A research programme has been established in Northern Ireland to investigate the potential for retaining crossbred females in the hill environment, as replacement breeding females, to improve the genetic potential of the hill flock. This paper presents the results from the first phase of the study which involved the production of the crossbred lambs from Scottish Blackface ewes (over 3-years) and the first year of the second phase, an evaluation of the performance of crossbred ewes as breeding females in the hill sector.

X-ray computed tomography (CT) can be used to accurately assess carcass composition in sheep (Sehested, 1984; Young et al., 2001) both in research and commercially, as part of a breed selection programme. Two different CT scanning methods have been used: a) the reference scan method where tissue weights are predicted from tissue areas in a small set of cross-sectional scans at ‘anatomical landmarks’, and b) the Cavalieri method where a larger number of scans are taken along the body. It is of interest to examine the accuracy of evaluations made using these two methods and the individual merits of the two methods depending on their application.

The amount and distribution of different body tissues changes as lambs grow and mature. Ratios of muscle to bone and of fat to muscle increase with growth post-weaning, as does muscularity (Jones et al., 2002), with the rate of change differing between breeds. Growth patterns have also been found to affect carcass composition (e.g. Thatcher and Gaunt, 1992). This preliminary study investigated the effects of growth rate on in vivo body composition and shape measurements and their relationships, in two contrasting breeds of lambs.

Muscularity of lamb carcasses, which is defined as the depth of muscle relative to dimensions of the skeleton (De Boer et al., 1974), is a commercially important trait in many countries. An objective index of muscularity was defined by Purchas et al. (1991) based on the weights of the muscles around a bone and the bone length. Jones et al. (2002) proposed an objective index to assess in vivo the shape of the muscle in the hind leg using X-ray Computed Tomography (CT), which had a phenotypic correlation of 0.63 with dissection measures of muscularity, as described by Purchas et al. (1991).

The development of genetic markers and their application to farm animals has progressed rapidly, opening new prospects for identifying chromosomal regions that control quantitative traits (quantitative trait loci or QTL). However, there is less activity in QTL identification in sheep than in other livestock species. Surprisingly few QTL have been published for traits of direct relevance to sheep meat production, apart from studies of individual major genes such as the callipyge locus (Freking et al, 2002). This suggests there may be more QTL effects still to be found in sheep. Hence, this study aims to identify QTL for carcass composition and meat quality traits. This will provide a basis for targeting genomic regions to verify QTL in independent sheep populations.

Keeping goats can make an important contribution to the livelihoods of small and landless farmers in Nepal, one of the world’s poorest countries. Work with four communities in the Dhanusha district of southern Nepal identified that a key constraint to goatkeeping in this area was doe infertility. Of 114 does over 10 months old that were monitored for a 12 month period, 33 did not kid and a further six were sold because of infertility. The objective of this experiment was to determine the effect of strategic supplementation of does’ diets on doe and kid performance, and on the contribution that the goat flock made to the livelihoods of the goatkeepers.

Most studies on digestion in the equine have been carried out with animals confined to stables with little or no exercise. An increased rate of digesta passage has been reported in exercised versus non exercise horses with an associated decrease in digestibility (Pagan et al., 1998). Microbial degradation makes an important contribution to diet digestibility in the equine. It is not clear however, if exercise has any effect on the composition and activity of the microbial population within hindgut which may impact on the digestion. The aim of this experiment was to assess the impact of exercise on microbial fermentation within the hindgut of the horse.

Digesta passage rate may have influenced previously reported work on the intakes, apparent digestibilities and nutritive values of complete pelleted diets containing unmolassed sugar beet pulp (USBP) at levels ranging from 0-800 g/kg dry matter (DM) when offered to ponies (Hyslop, 2002). This study’s objective was to compare total tract mean retention time (TMRT) of digesta using two algebraic calculation methods in the same ponies.

Recently, the costs of eight sheep diseases were calculated by Bennett and IJpelaar (2003). The highest annual costs were estimated for enzootic abortions in ewes (EAE) £20 M and toxoplasmosis £12M. In a survey among its members, the Moredun Foundation (1997) identified internal parasites (GI parasites), sheep scab and footrot as the most important sheep diseases, but these three diseases were not analysed by Bennett and IJpelaar (2003). The aim of this study is to estimate the benefits of reductions in the incidence or severity of these diseases, using the methodology of Bennett et al. (1999), and the benefits of reductions in disease incidence or severity. From this, marginal economic values for resistance are calculated and applied in selection index scenarios that mimic current sheep breeding schemes.

Gastrointestinal nematodes cause major losses to the UK sheep industry. As anthelmintic resistance is becoming a widespread problem alternative control methods are now sought. Breeding for improved parasite resistance is a possible control method (Woolaston and Windon, 2001). As genetic markers are now widely available there is considerable potential for application to livestock breeding through quantitative trait loci (QTL) detection and subsequent marker-assisted selection schemes. Although much work is underway, there are few published studies that identify QTL associated with parasite resistance. Therefore this study aims to identify QTL associated with parasitic nematode infection in a population of Scottish Blackface lambs using faecal egg count and Immunoglobulin A activity.

Osteochondrosis (OC) in pigs is an abnormal condition in the bone development which has high economic and welfare implications. Select for OC resistance would be difficult to achieve due to low polygenic heritability (∼0.06 – 0.15; Kadarmideen et al., 2004), unless a major gene exists. Segregation analysis provides evidence for major gene using only phenotypic data. Bayesian Segregation Analysis (BSA) method via Gibbs sampling is suitable for pedigreed animal population as shown in the application of this methodology to milk flow in dairy cattle (Ilahi and Kadarmideen, 2004). The main objective of this study was to conduct a BSA to determine whether osteochondral disease in pigs has mixed inheritance (major + polygenes).

The ▵9-desaturase enzyme adds a cis-9 double bond to fatty acids in adipose and mammary tissue. In the mammary gland, this reaction converts C14:0 to C14:1, C16:0 to C16:1, C18:0 to cis-9 C18:1 (oleic acid), and trans- 11 C18:1(vaccenic acid) to cis-9, trans- 11 conjugated linoleic acid (CLA). Oleic acid is of interest in human nutrition as a component of the “Mediterranean diet” and CLA has been shown to have numerous health benefits. Conversion of vaccenic acid to CLA in the mammary gland accounts for 75-80% of CLA found in milk (Lock and Garnsworthy, 2002), but activity of the Δ9-desaturase enzyme varies among individual cows irrespective of dietary manipulations (Lock and Garnsworthy, 2003), suggesting that it may have a genetic component. The objective of this study was to estimate the genetic variation in Δ9-desaturase activity in dairy cows using milk fatty acid profiles.

Cattle breeders, farmers and vets believe that the decline in fertility seen in recent years can be partially attributed to changes in rump angle with selection being for more angular cows. This suggests that animals with pin bones that sit above the hip bones (high rump angle) will have poorer fertility. Few studies have shown a significant relationship between fertility and rump traits. This study investigates the popular belief that high rump angle equates to poor fertility by examining the genetic and phenotypic correlation between rump angle and fertility traits. The relationship between rump angle and fertility was also examined to see if there was an intermediate optimum or threshold of rump angle for good/bad fertility. The correlation of other type traits (udder and composite traits) with fertility was also examined to see if they had potential to add information to the estimation of fertility breeding values.

Falconer and MacKay (1996) note that the measurement of a trait in two different environments may be considered as two traits rather than one. In this way it is possible, through the calculation of genetic correlations, to estimate to what extent the two measurements under different conditions are in fact the same characteristic and are determined by the same genes. The widespread use of AI in pig production has faltered due to problems with dilution and cryopreservation of semen and yet an industry split, where breeders and nucleus herds use AI extensively but multipliers and commercial producers do not, is becoming apparent. Reproductive traits are increasingly seen as an important component of overall pig production and while the genetic correlation between reproductive and production traits has been explored, little work has focused on the genotype by environment interaction of such fertility traits. The present study reports the genetic relationship of number born alive (NBA) in litters conceived naturally and by AI, and in rate of weaning to first service (WTFS-1).

A key to long-term sustainable enhancement of viable livestock production is the introduction of genetic traits that ensure that fertility and meat quality characteristics are compatible with farming environments and market needs. For example, the sheep industry could benefit if daughters of hill-breed ewes were of a crossbred genotype that enhances both carcass characteristics and fertility traits. Use of sires that confer better conformation is an option but does not significantly boost prolificacy. Introduction of the ‘Inverdale’ fecundity gene could change this. On a flock basis in the Romney breed, mean ovulation is increased by 1.0 and litter size by 0.6 in adult ewes carrying a single copy of this gene (designated as FecXI because it is on the X chromosome; Davis et al. 1992). Carrier males transmit it to all of their female offspring, these being heterozygous carriers of the gene unless it also is maternally inherited. In the latter instance, young would be infertile the homozygous genotype confers an undesirable ‘streak ovary’ phenotype. Although a number of sheep breeds world-wide exhibit significant ‘single gene’ effects on ovulation and litter size (Montgomery et al. 2001), Scottish hill sheep breeds show no evidence of this. Consequently, all ewe lambs generated by crossing these hill ewes with a ram carrying the Inverdale gene should be heterozygous. To ascertain whether such animals exhibit enhanced fecundity, an on-farm study investigated ovulation incidence in cyclic ewe lambs born to Cheviot or Scottish Blackface ewes that had been bred to Texel rams carrying a single copy of the ‘Inverdale’ gene.

There are many studies that show that breed, gender, age and feeding regime influence animal growth rate, meat yield and composition. These factors, together with slaughter and post-slaughter conditions, are thought to influence tenderness and flavour attributes of meat (Thompson, 2002)). Low variability is highly desirable and processes such as ‘A blueprint for improved consistent quality beef’ (MLC, 1999) in the UK has attempted to improve the level and consistency of beef eating quality. This project was designed to test a package of best-practice techniques, both on-farm and in-abattoir, on the eating quality of Scottish beef as assessed by a trained sensory panel and a recruited take-home panel.

There are many studies that show that breed, gender, age and feeding regime influence animal growth rate, meat yield and composition. These factors, together with slaughter and post-slaughter conditions, are thought to influence tenderness and flavour attributes of meat (Thompson, 2002)). Low variability is highly desirable and processes such as ‘A blueprint for improved consistent quality lamb’ (MLC, 1999) in the UK have attempted to improve the level and consistency of lamb eating quality. The purpose of this trial was to test whether the adoption of several key enhanced on–farm and in-abattoir practices led to improved eating quality throughout the lamb production season, especially for heavier, lean carcasses.

Whilst many of the on-farm factors identified as enhancing pigmeat meat eating quality are already standard commercial practice, variability in quality is still a problem whose reasons are poorly understood. Particular uncertainty exists about the effect on eating quality of increasing slaughter weight, a current development which facilitates reduced cost of production by spreading carcass overhead costs between more kg of saleable meat. However, this strategy means that pigs will be older at slaughter, which carries uncertainties about the risk of increased toughness and boar taint. In targeting a market for branded pigmeat of high eating quality, there may also be beneficial strategies for adoption in carcass selection and post-slaughter management. These questions were addressed as part of a research project on the improvement of meat eating quality in the Scottish red meat sector.

Currently 53 and 47% of prime beef production in Northern Ireland originates from beef and dairy herds, respectively. The beef herd comprises of a diverse range of genotypes which result in major variability in carcass weights, conformation and fat classification. The present study was undertaken to investigate the effect of genotype, carcass weight and fat classification, and pelvic hanging technique on meat quality.