Liquid feeding of growing pigs is believed to increase feed intake and growth performance compared to a dry diet. There is little information on the comparative feed conversion efficiency of pigs on the two forms of diet or the underlying physiological basis for the differences and how liquid diets affect the absorptive mucosa of the small intestine. This study was designed to investigate differences in feed utilisation and mucosal structure in modern genotype pigs offered equal amounts of feed in dry and liquid form. Additionally, the effect of reducing the pH of the liquid diet was considered.

It is well established that villus atrophy and crypt hyperplasia occur at weaning reducing the digestive and absorptive capacity of the small intestine in piglets. Liquid feeding appears to improve intake and growth in piglets but little is known about the effects of liquid feed on the small intestine mucosa. Deprez et al (1987) reported higher villi 11 days after weaning in piglets fed a liquid diet but there is little evidence that these changes persist in older pigs or are specifically due to diet form. This study is part of a series evaluating the effect of liquid feed on pig performance and adaptive changes in the absorptive mucosa of pigs from weaning to slaughter.

Newly weaned piglet diets are normally highly digestible, and as such are composed of ingredients with high acid-binding capacities (Bolduan et al., 1988), which are potentially detrimental to the maintenance of a low gastric pH. The most active element effecting the phenomenon of acid-binding capacity (ABC) is calcium, and a high concentration in pig starter diets can significantly reduce post-weaning growth performance (Hardy, 1992). However, the mechanism by which ABC retards growth performance is largely unknown. Accordingly a preliminary study was designed to examine the effects of ABC on gut morphological characteristics such as villous height, width and crypt depth, together with digesta pH which is an independent factor influencing microflora colonisation.

Concern over the use of prophylactic antibiotics and the potential of them being banned has increased interest in other methods of controlling disease. Specifically postweaning diarrhoea in the pig, often associated with E Coli (F4 K88ac) is a candidate for an alternative strategy. If in-feed additives can be demonstrated which effectively block the binding of the F4 (K88)ac pilli to the surface of the pig enterocytes then the severe form of the disease could be controlled without the use of antibiotics. The work reported here provides a screening method to determine whether potential in-feed additives can block the binding of purified F4(K88)ac to isolated brush border membranes taken from neonatal F4(K88)ac positive pigs.

Contamination of pig feed with enteric pathogens such as salmonellae has implications for the dissemination of salmonellosis in pigs and subsequent spread of these organisms through the food chain to humans. Liquid feed has the potential to be a vector for enteropathogens unless it is sterilised. However, if liquid feed is fermented with lactic acid bacteria (LAB), the production of lactic acid and consequent reduction in pH have an antimicrobial effect that can eliminate potential pathogens from the feed. The objective of this study was to determine whether the temperature at which fermented liquid feed (FLF) is fermented and maintained and the length of fermentation time affect the ability of Salmonellae to survive in the feed.

The effective level of dietary supplementation of vitamin E and vitamin C is difficult to define because it depends of several factors such as composition of the diet, feed consumption, rate of growth, animal production and living conditions, stress, crowding and environment. Research has demonstrated that supplemental vitamin E improved litter size, increased sow serum a-tocopherol content and enhanced health status (Mahan, 1994; Wuryastuti et al., 1993). Some reports have suggested that the low plasma and tissue levels of a-tocopherol in new-born pigs, suggests a low rate of vitamin E transfer across the placenta which is not influenced by dietary supplementation of the sow during pregnancy. The aim of this experiment was to determine the effect of vitamin E and vitamin C supplementation of sow diets on transfer of vitamin E to piglet tissues via placenta, colostrum and milk.

Immediately following weaning, voluntary food intake in the young pig is low and very variable. This can lead to reduced digestive efficiency and poor physical performance. One approach to try to stimulate intake is to manipulate the physical form of the diet. Previously it has been shown that, contrary to popular belief, young pigs are very adaptable with regards to diet presentation and in particular with respect to pellet size(Edge et al., 2000). Pigs from 10 to 56 days of age would consume a 5.0mm pellet as readily as a 1.8mm pellet with no adverse effects on production variables.

In intensive pig production systems piglets are weaned at between 21 and 28 days of age and it is common for piglets to take a few days to discover and accept solid food as a source of nutrients and this results in a loss of weight (the weaning growth lag). Therefore, if a means could be found to encourage the acceptance of solid food by piglets, benefits in terms of their growth and welfare would ensue. The transmission of information about foods from one animal to another has been demonstrated in the rat (Galef, 1993) and ruminants (Provenza and Balph, 1987) but there have been no studies with pigs at the time of weaning. Therefore, piglets were tested in pairs of experienced and inexperienced animals, with varying degrees of contact, with constant access to food over a period of seven days after weaning of the inexperienced animals.

Standards for organic pig production recommend that growing pigs are maintained on pasture. There is currently no information on the nutritional implications of such a system, since grazing intakes have not been recorded in pigs of this production stage. This study used n-alkane methodology previously validated in sows (Wilson et al., 1999) to measure the herbage intakes of individual pigs under such conditions.

Recent increases in mechanisation, a trend towards larger dairy units and current financial pressure on dairy farmers all combine to result in a reduction in labour and therefore time available to spend with the animals. increasing numbers of stock per attendant allowing them less time and opportunity to spend with their animals. If we view the reduction in human-animal interaction in routine husbandry tasks as positive because it frees up more quality time to spend with the stock; how will this best be spent to enhance the animal-worker bond, is it feasible in a practical situation and can we back this ideal up with monetary values and benefits to the different interested parties of the industry? This survey was designed to compliment some experimental work being carried out at Newcastle University (see companion paper). The objective was to gather information from dairy farmers on the heifer rearing systems currently in use; establish the different levels of human interaction the heifer experiences during rearing in commercial practice and explore whether this relates to other indices of welfare and production.

The quality of hoof horn is related to 3 factors: architecture of the Stratum corneum (number of tubules and inter-tubular space), cellular factors (type of keratinization, orientation of keratin fibres) and inter-cellular factors (amount and chemical composition of the inter-cellular substance (Pellman et al., 1993). Kempson and Logue (1993) related poor hoof horn quality at 1 month before calving to the occurrence of moderate to severe solar haemorrhage at 10 to 20 weeks after calving. The objective of this experiment was to develop the use of texture analysis as a method to measure the structural strength of hoof sole tissue and assess the influence of sample width and bruising on structural strength.

Claw horn lesions are the most common cause of lameness in dairy cows and the development of lesions is related to the days in lactation. The lameness caused by this lesions is influenced by different factors (Offer et al., 2000). The objective of this experiment was to study the relationship of severity of lameness and severity of scoring for hoof horn lesions.

Activity of fast growing broiler chickens is known to decrease at two to three weeks of age, whereas slower growing hybrids are not only more active, but remain so throughout the growth period (Reiter and Bessei, 1998). The present experiment aimed to monitor diurnal patterns and time courses of activity in groups of commercial broilers fed one of two feed types differing in energy content. Activity was assessed using passive infrared detectors (PIDs), which sense movement of an object with a temperature different from that of the background.

Whilst the lying space requirements for housed pigs have been scientifically defined (Petherick, 1983) it may not be appropriate to extrapolate these directly to the hut space requirement in the outdoor situation, where understocking carries a potential thermal penalty. However, it is important that hut space is adequate for all sows to obtain shelter when desired. The objective of this study was therefore to determine the preferred hut space requirements for outdoor sows, with the rationale that an inadequate hut space allowance would increase the number of animals forced to rest outside in a suboptimal thermal environment.

Although often described as “welfare-friendly”, the greater freedom of movement and choice of environments offered by communal farrowing systems does have potential welfare risks, primarily for the piglets. The maternal qualities of the sow will have a greater influence on the survival and growth of piglets in this communal farrowing system, than in a conventional farrowing crate and may be influenced by genotype. The objectives of this study were to compare the welfare of sows and piglets housed in farrowing crates and a communal farrowing system and to investigate whether sow genotype influences the quantity and quality of maternal behaviour and subsequent litter performance.

It has been widely reported that the pigs responsible for tail biting under both commercial and experimental conditions, are those which show poor growth rates. This may be because of an inability to obtain food because of social factors or poor pen design, or an inability to utilise food because of health or metabolic disorders. A major reduction in protein:energy ratio in the diet has been shown to increase attraction to blood in an experimental tail chewing model (Fraser, 1987). The aim of this study was to clarify whether the increased attraction to blood is a consequence of a specific metabolic state resulting from a protein deficiency (with effects on neurotransmitter pathways, Harper and Peters, 1989), or whether it occurs under conditions of a reduced growth rate irrespective of a protein deficiency.

The use of fully slatted flooring and absence of bedding for finishing pigs are being questioned for welfare reasons at Council of Europe level and have already been made illegal in some EU member states. Part slatted flooring offers an alternative, but their success depends to a large extend on the correct use of functional pen areas by the pigs: dunging should take place on the slats, lying on the solid floor. Pen lay-out has a large effect on the degree of pen fouling. The effects of straw provision on the solid floor area are less well documented. The present study tests the hypothesis that pen fouling in a converted standard Dutch pig pen is not affected by straw use, but by the position of the single space feeder as well as the position of a 40 cm chain (toy).

Legislation in the United Kingdom states that all pigs should have access to straw or other material or object suitable to satisfy their behavioural needs (Welfare of Livestock Regulations, 1994). However, the use of straw bedding has not been universally adopted as its use is incompatible with housing systems which contain perforated flooring, and 76% of pig producers in the UK currently employ fully- or part-slatted finishing housing systems. The aim of this study was to investigate whether different lengths of chopped straw would achieve enhancements in pig welfare, by exploring the possibility that small quantities of chopped straw, in preference to unchopped straw, could constitute adequate provision in part- and fully-slatted systems, thus avoiding the blockage of perforated flooring.

In commercial practice, the mixing of pigs often occurs on more than one occasion. This can be very stressful for the pig, as new dominance hierarchies have to be formed at each mixing. Mixing piglets pre-weaning has been used as a method of removing the stress of mixing from the point of weaning (Allen et al., 2000; North & Stewart, 2000) but the effects of mixing at different ages on pre-weaning behaviour needs to be determined. The aim of this study was to determine if mixing piglets pre-weaning affects their sucking and social behaviour.

Newly weaned pigs frequently show high levels of oral-nasal behaviour directed towards penmates which may cause injury if taking the form of ear and tail biting. It has been suggested that such behaviours may be motivated by both behavioural and nutritional influences. This experiment was carried out to investigate whether the provision of nutrient blocks supplying minerals, trace elements and herbs could reduce penmate-directed behaviours in weaned piglets.