In recent years the quantity of grass silage as big bales has increased substantially, both in the UK and elsewhere. Eyers (1989) reported that about 16% of the grass silage dry matter (DM) conserved in England and Wales was in the form of big bales.

Whilst there is now considerable information on the composition, nutritive value and laboratory procedures for predicting the digestibility and energy value of clamp silage, there are few comparable data for big bale silages. The objectives of the present work were to examine the composition, digestibility and energy value of a population of big bale silages and to compare relationships between laboratory measurements and digestibility in vivo with those derived earlier for clamp silages (Givens et al., 1989).

The design of self-locking barriers can affect cows’ skin injuries and impair welfare. This study aimed to propose and refine recommendations, expressed relatively to the cows’ dimensions, for self-locking barrier design to reduce risks for skin injuries on the neck/shoulder/back and on carpus of dairy cows. We recorded individual body dimensions and the dimensions of self-locking barriers (e.g. top rail height) and assessed skin injuries on 3801 cows from 131 loose-housing dairy farms. We explored the significant associations between presence/absence of skin injuries and self-locking barrier dimensions using weighted multivariable logistic regression, taking into account the diversity of feeding barriers within each farm. The robustness of the models was assessed by cross-validation. Cows had skin injuries mainly on the neck/shoulder/back (29.0%) and, to a lesser extent, on the carpus (14.0%). The final multivariable logistic regression models comprised 13 factors for skin injuries on the neck/shoulder/back, and 11 factors for skin injuries on the carpus. Skin injuries were significantly reduced when the self-locking barriers were inclined (neck/shoulder/back) and when the cows used a feeding table (i.e. flat) instead of a feeding manger or cribs (i.e. hollow) (carpus). A top rail height >1.05 × cow height (measured at withers) was significantly associated with fewer skin injuries on the neck/shoulder/back and on carpus. Skin injuries on the neck/shoulder/back and carpus were significantly reduced when the bottom rail was on the food side relative to the wall, and at a height <0.39 of cow height. Skin injuries were significantly less frequent when the separation wall had no sharp edges on the food side (neck/shoulder/back), was >0.4 of cow height (carpus), was thinner than 15 cm (neck/shoulder/back and carpus) and when the height of the feeding step was 0.04 to 0.1 of cow height (neck/shoulder/back) and the length of the feeding step was <0.2 of cow length (carpus). A headlock articulation nut positioned between 0.62 and 0.78 of cow height significantly reduced skin injuries on the neck/shoulder/back. Here, by combining the diversity of on-farm self-locking barriers and their respective dimensions, we were able to refine the International Commission of Agricultural and Biosystems Engineering recommendations for self-locking barrier design and to propose new ones. This information now needs to be confirmed on other datasets, but can already help farmers and dairy industry stakeholders improve the design of self-locking barriers to improve dairy cow welfare.

Two experiments involving the sequential slaughter of intensively fattened store lambs were each carried out over a period of 12 weeks. In the first experiment the lambs were offered a concentrate diet ad libitum. In the second experiment they were offered swede turnips ad libitum with a limited amount of concentrates.

In each experiment, similar groups of lambs were slaughtered at equal intervals in order to measure progressive changes in live weight, carcass weight and dry-matter intake. Carcass-weight gain as a proportion of live-weight gain was found to be 74% in the first experiment and 86% in the second experiment.

Many tens of thousands of tonnes of manufactured feed are consumed by farm animals each year and yet the incidence of infectious diseases contracted from this source is extremely low.

The potential disease hazards include, in alphabetical order, anthrax, botulism, bovine spongiform encephalopathy, foot and mouth disease, listeriosis, Newcastle disease (pigeon paramyxovirus infection), salmonellosis, swine fever and swine vesidular disease. The control of each of these diseases involves a number of different procedures, including the appropriate handling and treatment of the feed, the use of suitable management techniques on the farm, the vaccination of susceptible stock and either the treatment or slaughter of infected animals, or those animals in contact with them.

Several of the diseases (foot and mouth disease, swine fever and swine vesicular disease) have been eradicated from the U.K. while others (anthrax and botulism) occur only infrequently. On the other hand, the presence of salmonellas in feed does constitute a continuing problem since, although organisms do not usually cause disease in animals consuming the feed, they may ultimately cause gastroenteritis in people who either handle or consume meat derived from the animals concerned.

Production diseases in dairy cows are multifactorial, which means they emerge from complex interactions between many different farm variables. Variables with a large impact on production diseases can be identified for groups of farms using statistical models, but these methods cannot be used to identify highly influential variables in individual farms. This, however, is necessary for herd health planning, because farm conditions and associated health problems vary largely between farms. The aim of this study was to rank variables according to their anticipated effect on production diseases on the farm level by applying a graph-based impact analysis on 192 European organic dairy farms. Direct impacts between 13 pre-defined variables were estimated for each farm during a round-table discussion attended by practitioners, that is farmer, veterinarian and herd advisor. Indirect impacts were elaborated through graph analysis taking into account impact strengths. Across farms, factors supposedly exerting the most influence on production diseases were ‘feeding’, ‘hygiene’ and ‘treatment’ (direct impacts), as well as ‘knowledge and skills’ and ‘herd health monitoring’ (indirect impacts). Factors strongly influenced by production diseases were ‘milk performance’, ‘financial resources’ and ‘labour capacity’ (directly and indirectly). Ranking of variables on the farm level revealed considerable differences between farms in terms of their most influential and most influenced farm factors. Consequently, very different strategies may be required to reduce production diseases in these farms. The method is based on perceptions and estimations and thus prone to errors. From our point of view, however, this weakness is clearly outweighed by the ability to assess and to analyse farm-specific relationships and thus to complement general knowledge with contextual knowledge. Therefore, we conclude that graph-based impact analysis represents a promising decision support tool for herd health planning. The next steps include testing the method using more specific and problem-oriented variables as well as evaluating its effectiveness.

One of the major limitations in nutritional studies of lactation in dairy cows is the unknown contribution of body tissues to the energy status of the animal. Both fat and protein are thought to be mobilised in early lactation (Bauman and Elliot, 1983) when nutrient intake is insufficient to meet the demands for energy and amino acids. The present experiment investigates the effects of diet on changes in weights of chemically determined fat and crude protein (CP) in the carcass and non-carcass fractions over the first 29 weeks of lactation.

Body composition was measured by serial slaughter of autumn-calving dairy cows offered grass silage (206 g CP and 18.56 MJ GE per kg DM) ad libitum and 3(L), 6(M) or 9(H) kg DM/day of concentrate (206 g CP/kg DM)(Sutton, Aston, Beever and Fisher, 1992). Cows with post-calving live weights between 500 and 700 kg and previous lactation yields between 5000 and 7000 litres were used, and were blocked for parity and expected calving date before allocation across treatments and slaughter times. Six cows were slaughtered at 2 to 4 days post partum (week 0), and two from each treatment (one 2nd, and one 3rd or 4th parity) at 2, 5, 8, 11,14,19, 24 or 29 weeks post partum. After slaughter the right half carcass and all other non-carcass components were frozen and minced before chemical analysis for fat, CP, ash and water. All weights were adjusted by covariance for live weight post partum and parity. Energy content was calculated assuming values of 39.19 and 23.23 MJ/kg for fat and CP respectively.

The in situ degradation of the washout fraction of starch in six feed ingredients (i.e. barley, faba beans, maize, oats, peas and wheat) was studied by using a modified in situ protocol and in vitro measurements. In comparison with the washing machine method, the modified protocol comprises a milder rinsing method to reduce particulate loss during rinsing. The modified method markedly reduced the average washout fraction of starch in these products from 0.333 to 0.042 g/g. Applying the modified rinsing method, the fractional degradation rate (kd) of starch in barley, oats and wheat decreased from on average 0.327 to 0.144 h−1 whereas for faba beans, peas and maize no differences in kd were observed compared with the traditional washing machine rinsing. For barley, maize and wheat, the difference in non-fermented starch in the residue between both rinsing methods during the first 4 h of incubation increased, which indicates secondary particle loss. The average effective degradation of starch decreased from 0.761 to 0.572 g/g when using the new rinsing method and to 0.494 g/g when applying a correction for particulate matter loss during incubation. The in vitro kd of starch in the non-washout fraction did not differ from that in the total product. The calculated ratio between the kd of starch in the washout and non-washout fraction was on average 1.59 and varied between 0.96 for oats and 2.39 for maize. The fractional rate of gas production was significantly different between the total product and the non-washout fraction. For all products, except oats, this rate of gas production was larger for the total product compared with the non-washout fraction whereas for oats the opposite was observed. The rate of increase in gas production was, especially for grains, strongly correlated with the in vitro kd of starch. The results of the present study do not support the assumption used in several feed evaluation systems that the degradation of the washout fraction of starch in the rumen is much faster than that of the non-washout fraction.

Aitrenogest (17 α -allyl-17-hydroxyestra-4,9,11-trien-3-one; Regumate Porcine; Hoechst Animal Health) is a synthetic progestagen which has been used to control and synchronise the ovarian cycle particularly in cyclic gilts. However progestagens have also been used in various species to induce and synchronise the first ovulation post partum. The present study was undertaken to determine the effect of altrenogest treatment on the reproductive performance of primiparous sows.

In previous research grazing dairy cows showed no response to whole-crop barley silage (WCB) cut at different stages of growth, but the crop yield and quality, and DM losses were optimised at 350 to 450 g DM/Kg (early to hard dough) (Hargreaves and Leaver, 1992). However tha effect of herbage availability on the response to WCB supplementation is not known, therefore the objective of this study was to examine this effect during mid to late summer.

Winter barley (var. Puffin) was harvested on 16th July at 380 g DM/Kg (soft dough) and a yield of 14 t DM/ha. The chopped material was stored in a bunker silo.

The chemical composition and the energy and protein value of five batches of condensed distillers solubles (CDS) originating from wheat were determined. The net energy for lactation (NEL) was derived from digestion coefficients obtained with sheep. The true protein digested in the small intestine (DVE) and the rumen degradable protein balance (OEB) were based on the rumen degradation rate (kdD), the rumen undegradable fraction (U) and intestinal digestibility of undegraded protein (%DVBE) predicted by regression equations derived from a data set of 28 protein feeds with kdD, U and %DVBE determined in situ. The CDS is a by-product with a high, but very variable CP content (238 to 495 g/kg DM). The CP contained on average 81% amino acids, with glutamine as main component (on average 21.8% of CP) and a relatively good lysine proportion (3.0%). Further, CDS contains quite a lot of crude fat (mean±SD: 71±14 g/kg DM), glycerol (95±52 g/kg DM) and sugars (123±24 g/kg DM) resulting in a high organic matter digestibility (88.6±3.0%) and high NEL content (8.3±0.4 MJ/kg DM). The protein value showed a large variation, with DVE ranging from 122 to 244 g/kg DM and OEB from 50 to 204 g/kg DM. Wheat CDS is a rich source of minerals and trace elements with exception of calcium.

The effects of freeze-branding young beef animals using two coolants were investigated and an attempt was made to avoid hide damage.

1. Branding with irons cooled in liquid nitrogen gave good markings but resulted in severe hide damage.

2. CO2-branding caused much less hide damage but gave fewer legible brands.

3. Legible brands with both coolants always resulted in some marking of the hide.

4. Branding on the jaw provided a satisfactory means of identification without loss of hide value.

The majority of early lambing flocks in the UK consist of crossbred ewes which do not normally cycle at a time consistent with an early January lambing. Oestrus stimulation is therefore necessary and is generally achieved by the use of progesterone-impregnated sponges and Pregnant Mares Serum Gonadotrophin (PMSG). Alternative techniques to sponges and PMSG to induce oestrus may become increasingly important in the future if restrictions are placed on the use of synthetic hormones. The present study aimed to

• a) Investigate alternative ways of advancing the breeding season naturally using vasectomised males and ovariectomised, oestrus-induced females. (Teasing).

• b) Assess whether treatment of ‘teased’ ewes with melatonin would enhance any effect of teasers.

An experiment was conducted to evaluate the effect of dietary cimaterol, a β-adrenergic agonist, on growth, carcass characteristics and pelt quality of kit mink. The 40 standard dark and 40 sapphire mink kits were assigned to a control or to one of three treatment groups (five males and five females of each colour phase per group). Treatment consisted of the inclusion of 0·5, 2 and 5 mg cimaterol per kg (dry) of a standard ranch mink diet (control). All animals were weighed at the initiation of the experiment (24 July) and at 28-day intervals until 16 October. At slaughter (12 December) body weights were recorded and pelts measured for length and evaluated for fur colour and quality by experienced fur graders. Samples of fur from similar sites on each animal were removed for measurement of guard hair and underfur diameter. Frozen carcasses were analysed for protein and fat content. Mink final weight decreased with increasing concentrations of dietary cimaterol (P < 0·05). Pelt length, which was found to be highly correlated with body size, was also reduced by cimaterol treatment. Feeding 2 and 5 mg cimaterol per kg diet to male kits, and 5 mg/kg to female kits caused a significant reduction in the proportion of carcass fat and increased the proportion of carcass protein (P < 0·05). Fur fibre diameter for both guard hair and underfur was not significantly affected by dietary cimaterol. There was also no significant effect of cimaterol treatment on fur quality. Cimaterol treatment did not result in diversion of nutrients from body proteins to the synthesis of fur and pelt proteins. Results of this research indicate that oral administration of cimaterol to mink will be of little practical value in fur production.

Angora and Cashmere goats produce two distinctive major fibres. The hair coat of the Angora goat consists essentially of a single fleece of Mohair grown by secondary hair follicles with a limited production of guard hair from primary follicles. The average fibre diameter ranges from 22 to 45 urn. In contrast, the Cashmere bearing goat has a double coat comprising coarse guard hair produced by primary follicles with the fine cashmere underhair (preferably 19 μm diameter or less) produced by secondary hair follicles. In the Angora goat, the fibres grow essentially continuously while in cashmere, hair follicle activity is determined largely by seasonal changes in photoperiod. The objective of this study was to investigate the effects of prolactin and melatonin, hormones implicated in the photoperiodic response, on the pattern of growth of secondary hair follicles isolated and maintained in vitro.

Female pigs (sows) which had lactated for about 10 days were allocated at random either to a control group or to a group given 75 mg methallibure per day for 5 consecutive days, followed by an intramuscular injection of 1000 IU PMSG. All sows were mated as soon as they came into oestrus and again 24 hr later. Nineteen out of 21 treated sows exhibited a controlled oestrus 9·4 + 0·25 days after weaning, compared with 21 out of 23 control sows in 8·2 + 0·64 days. Fourteen treated and 17 control sows conceived at that oestrus resulting in total pigs born per litter of 9·4 and 9·9 respectively. None of these differences was statistically significant.

The objective of any livestock breeder is the identification of stock of superior genetic merit with respect to some goal for the production of future generations; their objective is the estimation of genetic merit. Traditional breeders achieve this simply by visual appraisal. Some breeders have realised the value of collection of performance records to make the assessment more objective. The animal’s performance record however results not only from the animal’s genetic make-up but also from the management and other non-genetic factors (age of dam, age of measurements) that it has experienced. Best Linear Unbiased Prediction (BLUP) is a method to estimate genetic merit (or breeding values) of animals. BLUP is universally regarded as the best method available to us to predict genetic merit of animals when performance records have been collected In a variety of herd, year, season and management environments. Considerable investment of time and money Is made in the organisation of unique animal identification and collection of records. It is therefore appropriate that maximum use is made of those records in the accurate prediction of genetic merit of individual animals.

• 1. There are many ultrasonic machines using a range of techniques varying in sophistication to measure fat and muscle depths for predicting carcass composition. An evaluation of four techniques was conducted by the Meat and Livestock Commission (MLC) to enable potential users to select the most appropriate technique based on accuracy, practicality and cost.

• 2. A total of 150 commercial sheep comprising approximately equal numbers of castrates and ewes were evaluated in five batches of about equal size in lairage at one of two abattoirs. Live weight was recorded together with fat and muscle measurements from the Aloka, Dynamic Imaging, Dumatic and Velocity of Sound (VOS) ultrasonic techniques.

• 3. The Aloka is a B-Mode real-time medical scanner which is currently used on cattle in Australia. The Dynamic Imaging is also a B-Mode real-time medical scanner which is currently used in MLC's Sheepbreeder Service.

Two trials were completed using a total of 135 female hoggets from 5 to 7 months of age. The effect of implanting 15 or 30 mg. testosterone propionate or 2·5 mg. oestradiol benzoate plus 25 mg. testosterone propionate was assessed on average daily gain, slaughter characteristics and carcass yield. In the second trial some additional data were obtained on carcass quality.

No significant effect of testosterone with or without oestradiol could be demonstrated on average daily gain, carcass yield, carcass score or the proportion of retail cuts in the carcass. There was some indication that the treatment could yield carcasses with less subcutaneous fat without diminution of eye muscle size.

In the first of two experiments of 6 × 6 Latin-square design a diet of barley, soya bean meal and fish meal, known to give an adequate lysine intake (56 g/day) at the level of feeding adopted, was diluted with maize starch to give crude protein intakes ranging between 448 and 923 g/day but with the lysine intake held constant by using synthetic lysine in the diets. The diets were given to sows suckling ten piglets between days 12 and 30 of lactation. Dietary amino acid adequacy was assessed by changes in plasma urea, urinary urea, urinary nitrogen and plasma amino acid concentrations. The dietary amino acid supply became limiting with a protein intake of approximately 730 g/day. In the second experiment, a diet of similar composition was used with varying additions of synthetic threonine, methionine, isoleucine and tryptophan: the control diet contained all the synthetic amino acids added, the basal diet none and the other diets were formed by adding groups of three out of the four synthetic amino acids. On the basis of some of the variables studied, it was concluded that, for this diet, threonine was the limiting amino acid after lysine.

Obestatin is a gastrointestinal peptide having wide-ranging effects on cell proliferation; however, its mechanism of action remains poorly understood. Thus, the aim of the study was to elucidate the effect of exogenous obestatin on the postnatal structural development of the small intestine. Seven-day-old piglets with an average BW of 1.56 ± 0.23 kg were divided into four groups (n = 10) that received intragastrically obestatin (2, 10 or 15 μg/kg BW) or vehicle. After a 6-day experimental period, morphological analysis of gastrointestinal tract and small intestine wall (mitosis and apoptosis indexes, histomorphometry of mucosa and muscularis layers) was performed. The study revealed a seemingly incoherent pattern of the histological structure of the small intestine among the experimental groups, suggesting that the effect of obestatin is both intestinal segment specific and dose dependent. Histomorphometric analysis of the small intestine showed that higher doses of obestatin seem to promote the structural development of the duodenum while simultaneously hindering the maturation of more distal parts of the intestine. Intragastric administration of obestatin increased the crypt mitotic index in all segments of the small intestine with the strongest pro-mitotic activity following the administration of obestatin at a dose of 10 and 15 μg/kg BW. The significant differences in the number of apoptotic cells in the intestinal villi among the groups were observed only in proximal jejunum and ileum. In conclusion, it seems that obestatin shows a broad-spectrum of activity in the gastrointestinal tract of newborn piglets, being able to accelerate its structural development. However, the varied effect depending on the intestinal segment or the concentration of exogenous obestatin causes that further research is needed to clarify the exact mechanism of this phenomenon.