In arid and semiarid areas, the possibility of growing high yielding forages such as corn is limited. Therefore interests have been focused on growing plants which are highly able to express their potential in hot and dry conditions. Millet has recently received considerable attention as a suitable candidate. Some advantages include: rapid growth rate, relatively high resistance to drought and salinity, moderate protein content, palatability and absence of prussic acid. The objective of this experiment was to evaluate the fermentation quality and digestibility of millet silage as affected by various additives.

Some herbaceous legumes have shown a dry tolerance and had been used as animal feed. However, some of those plants have anti nutritional compounds such as tannins that can interfere on intake and digestibility. Tannins are polyphenolic compounds originated in a secondary metabolism of the plant as protection against insects, birds and as a result of drought, temperature or soil fertility. In order to preserve the tannin for experimental purposes, it is suggested that the hay preparation should be made under shadow. The objective of this work was to compare the concentration of phenolics compounds in forage legumes havested in dry and wet seasons and under sun, shadow and air circulation dry.

During the last two decades, there has been increased interest in planting halophytes in the salty agricultural regions of central Iran for improved animal production and environmental protection. The aim of this study was to determine the chemical composition and protein digestibility of some halophytes (Atriplex sp., Sauda sp., Kochia sp. and Gamanthus sp.) using in vitro technique, and mobile nylon bag and three step procedures.

Yeasts are the first micro-organism that become active in the silage upon exposure to air, using the residual sugars and lactic acid to produce carbon dioxide. Maize silage is particularly prone to spoilage as maize silage tends to have a larger concentration of water soluble carbohydrates, which was considered to be a better substrate for micro-organisms than volatile fatty acids (Auerbach et al., 1998). The aim of this experiment was to measure the effect of inoculating maize silage with Maize-all GS (inoculant) and Sil-all Fireguard (inoculant and preservative) on aerobic stability.

In the developed world, wheat straw is commonly regarded as a waste product. An obvious application is as an animal feed source, however, the digestible sugars (cellulose and hemicelluloses) are chemically bound within lignified cell walls. This severely inhibits its digestibility and thus its energy and nutritive value by ruminants. Various methods have been used to increase its digestibility and nutritive value by breaking, or weakening the linkages between the lignin and hemicelluloses prior to it being fed to ruminants. Where grass and silage are abundant and relatively cheap sources of animal feed, it is not cost effective to try and utilize this resource. However where alternative feed sources are not readily available, low cost upgrading of an abundant source of fodder would have many benefits. The objectives of this study were to use 8 strains of white rot fungi to pretreat wheat straw to improve its in-vitro digestibility, and to determine the impact of the fungi on the in-vitro digestibility method, i.e. to see if fungi have any adverse effects on the digestibility method.

Short chain fatty acids, produced from the fermentation of feedstuffs, form the ruminant’s primary energy source, as well as being precursors of glucose, protein and milk constituents (Dijkstra et al., 2000). The analysis of rumen fluid to estimate short chain fatty acids involves the addition of internal standards and analysis by gas chromatography. NIRS has been shown to have the potential to accurately and rapidly evaluate fresh silage chemical and biological parameters, including short chain fatty acids (Park et al., 1998). This study was undertaken to evaluate the potential of NIRS to accurately estimate the chemical composition of rumen fluid when a range of diets were fed to fistulated steers.

Whole crop wheat and maize silages are becoming more widely used as additional winter forage for ruminant animals Whole crop wheat and maize forage can be produced with greater nitrogen efficiency than grass swards (Aarts et al., 1992) and it has been shown that forage maize inclusion in grass silage based diets has resulted in increased DM intake, milk yield and milk protein content (Keady et al., 2002). Consequently a robust, cost-effective method to accurately characterise the feeding value of these forages is required. Previous research at this Institute (Park et al., 1998) has shown that NIRS can be used successfully to estimate the chemical and biological parameters of grass silage. The objective of this study was to examine the potential of NIRS to predict the chemical composition of whole crop wheat and maize silages.

Strained rumen fluid (SRF) obtained from slaughtered animals has been used to estimate in vitro dry matter degradation (DMD) of feeds (Mohamed et al., 2002). This study compared in vitro methods using SRF either from fistulated or slaughtered sheep with in sacco method to estimate in vitro degradation of various feed raw materials.

Tannins can produce toxic and anti-nutritional effects in monogastric and ruminant animals: reduced feed intake, lower nutrient digestibility and protein availability. Leucaena leucocephala has high concentration of condensed tannins (about 6 % CT), however is probably the most widely in use tree legume in the world. The aim of this experiment was to evaluate different treatments to deactivate tannins in Leucaena leucocephala.

Plant cell wall polysaccharides are degraded by microorganisms provided that they produce the necessary enzymes and in sufficient quantities. Some polysaccharides, such as hemicelluloses, are highly complex branched structures, which require a wide range of enzymes for their degradation. A further complication in the hydrolysis of these polysaccharides occurs because some sugar residues are esterified to phenolic compounds, such as p -coumaric and ferulic acids. Feruloyl groups reduce accessibility of enzymes to the main chain and may also act as nucleation sites for lignification. Feruloyl esterases and arabinofuranosidases which work in synergy with main enzymes to increase the removal of phenolics, including lignin, should enable xylanolysis and cellulolysis to proceed more effectively. The effect of enzyme preparations rich in debranching enzymes on the degradation of poor quality roughage was examined.

Weaning demands a nutritional change and although piglets voluntarily consume creep feed in appreciable quantities from about 4-5 weeks of age, they still rely on milk as an important food source for a long time (Boe 1991). The purpose of this study was to investigate the differences in pre-weaning behaviour of piglets weaned at 3, 4 or 5 weeks of age.

Meat from exotic farm animals such as farmed deer and wild boar is currently widely available to the consumer within the UK. Despite a rapid growth in production there is a paucity of research that focuses on the welfare of these animals during their slaughter. The objective of this study was to survey deer and wild boar producers to establish information about current slaughter practices. In addition producers’ opinion on current practice was ascertained.

Comfort is of particular importance during the peri-partum period when cows are particularly susceptible to claw lesions. Claw lesions are reduced by housing on straw bedding which is thought to be in part attributable to the physical surface (Bergsten and Frank, 1996) but also to the fact that cows in straw yards spend more time lying down (Singh et al., 1993). The objective of this study was to determine the influence of relief areas in cubicle housing and out-wintering on a woodchip pad on behaviour and foot lesion scores of pregnant dairy heifers.

Pigs can be physiologically and psychologically affected by their environment and by interactions with other animals. Whether the psychological effects are great enough to cause depression is not known. We hypothesised that should depression occur it would be most likely in victimised pigs. In this study we investigated what behavioural measures could be used to indicate levels of victimisation.

Teeth resection is a method of controlling the injurious effects of the aggression displayed when newborn piglets fight to establish a teat order. However, recent European legislation discourages the practice (Commission Directive 2001/93/EC). The objective of this study was to assess the effect of clipping and grinding piglets’ needle teeth, compared to leaving them intact, on the welfare of piglets in farrowing crates.

Although the efficiency of transfer of N is higher in dairy cows than in growing ruminants, there is still room for improvement as only approximately 30% of the ingested N is recovered in milk protein. The remainder is excreted in faeces (30%) and urine (40%). This review will focus on the metabolic utilisation of the digested N fraction: where in the body is this N partitioned between anabolic (milk protein, tissue growth) and catabolic (urine) fates and what factors influence its efficiency of use?

Rumen fermentation and splanchnic metabolism affect the relationship between the chemical composition of the feed and the nutrients available to the mammary gland and other peripheral tissues in the dairy cow. Conventional feed evaluation systems don’t allow the nutritionist to design diets based on the demand for specific nutrients, but primarily base predicted animal responses on the energy content of digested organic matter. In a nutrient based feed evaluation system (NBFE) the chemical composition of the feed and monitoring of ruminal variables in real time can be used as input to simulation models describing fermentation and intermediary metabolism. The aim of the system is to analyse/evaluate dietary adjustments according to specific metabolic needs of the dairy cows under specified physiological conditions. It’s mandatory that NBFE systems account for all major nutrient fractions absorbed and metabolised in the dairy cow. Short-chain fatty acids (SCFA) have been particularly troublesome in this respect because it generally has been assumed that a large proportion of ruminally absorbed SCFA is metabolised by the rumen epithelium and therefore is not available to the liver or peripheral tissues. The aim of this presentation is to review the interrelations between ruminal production, portal absorption, and peripheral availability of SCFA in the ruminant and to discuss how the metabolism of SCFA might be incorporated into future NBFE systems.

The splanchnic tissues of cattle are comprised of the portal-drained viscera (PDV; the gastrointestinal tract, pancreas, spleen, and associated adipose) and the liver. The PDV and liver act as an anatomically and functionally integrated unit which monitors the flow of nutrients from the diet and integrates their metabolism with body requirements. This integration occurs via a myriad of orchestrated metabolic, neural, and endocrine signals which through interplay with the brain ultimately determine appetite, digestive function and the balance between nutrient availability and use for productive function. This review will focus on specific aspects of endocrine metabolism by these tissues in cattle, and consider their potential impact on nutrient intake during lactation.

Rations for dairy cattle are currently balanced to meet needs for energy, protein, vitamins, and minerals. While individual vitamins and minerals are considered, energy and protein terms are generally treated in aggregate, i.e. requirements have not been defined for the nutrients comprising those terms. A number of examples can be drawn from the literature demonstrating that milk yield and composition can be affected by varying the type of energy fed even when diets are isocaloric. While progress has been made towards the goal of balancing dairy rations to meet individual amino acid needs, we still have not achieved the level of sophistication realized for other commercial species. Although significant efforts have been undertaken to describe ruminal metabolism, ruminal output predictions have been largely channeled into aggregated descriptions of postabsorptive metabolism that assume constant fractional conversions of energy and protein to milk. If further progress is to be made, ruminal predictions must be matched with postabsorptive equations that track the key metabolites through that system to the tissues of interest. In that manner, the effects of individual metabolites on endocrine status and tissue metabolism can be more accurately reflected. To succeed in this latter effort, a quantitative understanding of the post-absorptive tissues is required. The splanchnic tissues are critical components of the postabsorptive system as they mediate absorption of nutrients and play a role in regulation of metabolite availability to the remaining postabsorptive tissues. The pertinent questions related to their metabolism are: 1) what proportion of each metabolite presented to the tissue is utilized by the tissue, and 2) is the proportion used constant across diets and physiological states?

The concept of using immunological strategies to boost reproductive performance in sheep and cattle is far from new, with products such as Fecundin®, which involved active immunisation against the weak androgen, androstenedione, having been released nearly 20 years ago. However, whilst effective in sheep, immunisation against androgens was not effective in inducing multiple ovulation in cattle (unpublished observations), in which the natural rate of twinning is low (<4%). The purification of inhibin in the late 1980’s and the subsequent elucidation of its role in controlling follicle stimulating hormone (FSH) release from the pituitary represented an alternative means to increase prolificacy in domestic ruminants. Intense research effort throughout the 1990’s utilising active inhibin immunisation showed that while this approach was quite successful in sheep, results in cattle were less promising due to the extreme variability of the response obtained both between animals and within a single animals across successive cycles. Further, while numerous studies have shown that with correct identification and management production of twins in cattle can lead to significant economic gains, the possibility of more than two young clearly raised welfare concerns for both sheep and cattle in terms of dystocia and post-natal welfare of both the mother and her offspring. Over recent years, however, continued research into the control of ovarian follicle development in ruminants has suggested alternate immunological strategies that could be used to modulate prolificacy in a more reliable and controllable manner.