The antibiotic Actaplanin is a complex of glycopeptide compounds produced by Actinoplanes missourrensis. When included in feed as a performance enhancer it has been shown to increase milk production of dairy cows (McGuffey et al. 1983). Actaplanin is associated with reduced proportions of acetate and increased proportions of propionate in rumen fluid and a depression in milk fat proportion may result (Clapperton et al. 1987). The aim of the trial reported here was to monitor the effects of feeding 960 mg Actaplanin/head/d to dairy cows throughout two successive lactations.

Recent work concluded that when lactating dairy cows are fed a relatively high energy diet (Garnsworthy and Jones, 1987), increasing the dietary undegradable protein (UDP) supply to those which are fat at calving leads to increased mobilisation of body fat reserves; however, increasing the UDP supply to those which are thin at calving results in reduction of voluntary feed intake, but does not affect the change in condition or milk yield. Little difference was found in yields of cows fat at calving receiving a relatively high UDP diet post calving, and cows thin at calving receiving a high or low UDP diet. Similar results were obtained with diets of lower energy and protein content (Jones and Garnsworthy, 1987). The investigation reported here aimed to examine the effect of body condition at calving on the response to energy level in the diet.

A major problem facing breeders interested in using bulls from other populations is that the foreign bull evaluations cannot be directly compared with the evaluations produced in the United Kingdom (UK). This is due to differences in the units of measurement, the base against which all bulls are compared and the method used to express the merit of the bulls. In order that selection is possible on an equal basis, it is necessary to be able to convert bull evaluations from the scale used in the country of export to that used in the importing country.

The general formula used to convert evaluations is of the form Y = a + bX where Y is the converted evaluation, X is the evaluation in the exporting country, a is the difference between the bases used for bull evaluations and b is the factor to take account of the differences in scale.

The objective of the experiment was to compare the production and reproductive performance of dairy cows in two environments known to produce large differences in cow behaviour - the cubicle house and straw yard. In addition an injection of prostaglandin analogue was investigated in both environments as it has been previously reported that a post-partum injection.of PGF2 α can improve poor reproductive performance (Knight, 1985).

Forty multiparous spring-calving cows were allocated for 12 weeks prepartum and 12 weeks postpartum t0o either a covered strawyard (S) stocked at 0.12 cows/m2 or a cubicle house (C) stocked at 0.17 cows/ m2. One half of each group received an injection PGF2 (P) 21 days post-partum, the other half receiving no injection (N). All cows were offered a complete diet ad libitum (ME 11.9 MJ/kg DM, CP 164g/kg) and results for the animal production and reproduction are presented for the postpartum period, and results for hoof condition presented for the entire winter.

PH20 (IPT (International) Ltd, Newark) is a water-insoluble polymer gel of acrylic acid which has been shown to improve the digestion of silage in the rumen, leading to improved live-weight gain and feed conversion efficiency in beef cattle (Garnsworthy, 1987) and, on a large number of commercial dairy farms, has led to savings in concentrate usage. Increases in milk yield have been found on only a minor number of farms and it appears that with cows in mid to late lactation unless the concentrate allocation is reduced, feeding PH20 will result in greater deposition of body reserves. The objective of the trial reported here was to study the response by cows in late lactation to PH20 under grazing conditions.

Oilseed rape meal is high in protein and available in the UK relatively cheaply. Toxic constituents limit its inclusion in feeds for pigs and poultry but this is not a problem with ruminant animals where microbial action in the rumen removes them. However, the bitter taste of rape meal has been thought to reduce its palatability for ruminant animals (Stedman and Hill, 1987) and it is recommended that its inclusion in compound feeds for cows should not exceed about 150kg/tonne; masking agents are incorporated to reduce this limitation.

The question to be addressed can be summarized as “can higher rates of inclusion of rape meal in dairy compound feeds be concealed by more mask?”. Twelve dry cows in late pregnancy were offered feeds with various levels of rape meal in combination with several levels of mask and rate of consumption was monitored.

Energy insufficiency appears to be one of the major causes of the high preweaning mortality rate prevalent in the swine industry (English and Smith, 1975). This observation is supported by (1) the limited energy reserves in the neonatal piglet and (2) the increased survival rate found in some studies in piglets whose dams received supplemental fat during late gestation and thus provided the piglets more milk fat (Pettigrew, 1981). Oral doses of fat, for example corn oil, have been given to piglets as energy supplements, without improving their survival rate (Pettigrew et al., 1986). This lack of response may be due to the high survival rate in the unsupplemented controls, to an inadequate amount of fat dosed, and/or to an insufficient ability of the piglets to utilize the fat.

Pigs which are small and relatively ill-thriving when their litter-mates are due to be weaned constitute a major problem in practice because they are much more difficult to establish after weaning than their larger litter-mates. Because of this, many producers foster 8 to 10 of these poorer pigs to a newly weaned ‘nurse’ sow following weaning from their own dam and delay weaning them for a further week or more. Such fostering of poor pigs when weaned from their own dam suffers from the disadvantage that it delays the rebreeding of the ‘nurse’ sow and it can be ineffective if the sow fails to milk well. The chore-time Baby Pig Feeder, developed at North Carolina State University, has the potential to cater for the needs of poorer pigs at weaning and to reduce the need for ‘nurse’ sows. The Chore-time is an automatic feeder which involves the mixing of dry milk substitute and cold water and delivery of the mixture to a round trough, around which up to 10 pigs can feed. It can be programmed for milk to be delivered at hourly intervals or less frequently. The usefulness of this equipment was evaluated on a 200 sow commercial unit in which weaning took place around 3 weeks of age.

The deep body temperature of the newly born piglet (39°C) in many circumstances drops immediately after birth. A drop in body temperature of 2°C or more is considered to constitute chilling. When pigs are chilled they become lethargic and are more prone to overlying and starvation (Stephens, 1971). Because chilled piglets are less successful in competing for a suckling position and in obtaining colostrum they are more prone to disease such as scouring (Kelley, 1982). Lynch (1983) found in a farrowing house temperature of 24°C, 23 and 3 per cent of piglets had a body temperature of 37°C or less at 1 and 24 hours of age respectively. When farrowing house temperature was at 17°C, the proportion of chilled pigs (body temperature below 37°C) was 72,59 and 6 per cent at 1, 24 and 48 hours of age respectively. Thus, the incidence of chilling after birth can be extremely high and the consequences are likely to be serious. An experiment was carried out to investigate approaches for minimising the drop in piglet body temperature after birth and to examine the effects on piglet survival and growth.

Offering dry food to piglets prior to weaning at 3 weeks of age is a common commercial practice. Although it familiarises animals to dry food there is little quantitative information on the effects of the amount of food eaten on the young pigs' ability to utilise nutrients in the post-weaning period. In this preliminary study we compared the digestive utilisation of two diets (Table 1) based on either skimmed milk powder (diet M) or soya bean meal (diet S). Variations in pre-weaning food intake between individuals were imposed by the use of gavage feeding. No other supplementary food was offered before weaning.

To establish the effect of an Inadequate dietary energy intake during lactation on the repletion of maternal energy and protein stores post-weaning.

Forty-two crossbred, multi-parous (parity 2 to 5) sows were randomly assigned to diet on day-1 of lactation based upon ancestry and parity, Diets were (1) high-energy (66.9 MJ/day) and (2) low-energy (33 MJ/day). Lactation diets were prepared with maizestarch and soyabean meal and formulated to provide equal intake of all nutrients except energy during the 28-day lactation. Total daily nutrient intake was achieved in four proportional meals All litters were standardized to nine pigs/litter on day-1 of lactation. On day-14 of lactation, daily milk yield was estimated by the Weight-suckle-welgh method. Sows were weighed on day-1, day-21 and day-28 of 1actation. Maternal weight change was calculated using maternal weight postpartum and at weaning. On day-28 of lactation, ten sows (weight 182 to 258 kg) from each treatment were selected at random and assigned to metaboilsm crates for a 35-day post-weaning nitrogen and energy balance experiment.

There have been few published studies on the water needs of lactating sows under contemporary systems of feeding, housing and management. The literature available indicates that lactating sows provided with an unrestricted water supply show considerable individual variations in daily water consumption. Although ARC (1981) suggest that lactating sows should have access to an unrestricted water supply, an allowance of between 15 and 20 l/day has been recommended to meet the requirements for water. This study investigated the water demands of lactating sows provided with an unrestricted supply of water and to determine the stage of lactation on daily water use.

1. 1. The main commercial recording scheme operated for pig producers by the MLC is the Pigplan Recording and Costing Service, currently covering some 1,100 herds. The service records a basic list of herd performance and financial factors, with the processed results forming the basis of MLC field staff on-farm advisory services.

2. 2. The MLC Sow and Boar Monitoring Service was established in late 1983 using a bureau service with central computer processing. The service is available where it is felt necessary to undertake more detailed individual litter recording in order to identify particular weaknesses in production.

3. 3. Individual sow and boar details are recorded. Then, starting with the weaning of the last litter, details of all services over a period are submitted regularly. The records of each parity are completed with the submission of farrowing and weaning data. Processed results, in the form of tabulated printout, are provided for forward planning management aids, individual sow and boar summaries, and herd summary performance over a suitable period.

4. 4. In September 1987, 135 units were actively recording with an average herd size of 200 sows. Over 150,000 litter records have accumulated since the service started, representing some 66,000 sows from a total of 250 herds.

It is established that backfat depth and body condition during late pregnancy and lactation can be manipulated through changes in feed intake (Harker and Cole, 1984). Other work has shown that high level feeding throughout pregnancy is associated with a reduction in voluntary feed intake (e.g. Salmon-Legagneur and Rerat, 1962; Harker and Cole, 1985). However, it remains unclear whether high level feeding during late pregnancy alone has any effect on subseguent voluntary feed intake or changes in liveweight and backfat depth during lactation.

The present experiment was designed to compare the performance and body condition changes of sows fed different levels in late pregnancy followed by a common and relatively high feed level during lactation.

The present experiment has been designed to investigate the influence of variations in energy intake during both pregnancy and lactation on short- and long-term sow and litter performance. There is now sufficient evidence to suggest that the ARC (1981) factorial estimates of the energy requirements of the sow during pregnancy are too high, due, possibly, to an over-estimation of the maintenance energy component (MEm). Revised values, based on a constant ME value throughout psregnancy of 439 kJ ME/kg0.75 per day, have therefore been calculated and applied in the present experiment. An additional feature of the experiment is to provide information on the effect of lactation feed intake on the utilization of energy in subsequent pregnancies for maternal body weight gain.

Non-lactating sows are the only class of pig fed below appetite and can make use of bulky feeds including low dry matter materials such as liquid whey. Farmers who feed whey to pregnant sows from communal troughs complain of the difficulty of maintaining homogeneous body condition throughout the herd. The object of these experiments was to quantify the differences in intake between sows which produce this disparity and to indicate how feed dispensing systems might be controlled.

An increasing national demand for water coupled with a greater awareness of its potential for environmental pollution has augmented the concern generated by the relatively large quantities wasted on pig farms. Moreover, in the present financial climate this waste represents a useful source of cost saving, through the prospect of reduced supply, storage and disposal expenditure.

Several factors are understood to influence the use of water by pigs. Earlier studies at Seale-Hayne (Gill, Brooks and Carpenter, 1986), showed that scale fed pigs used 75.6% more water from Monoflow drinkers (nipple type drinkers) than from Arato 80 drinkers (bite type drinkers). Mount et al., (1971) indicated that temperature has an important effect on water consumption and Gill et al.,(1986) showed that the number of feeds per day was also of significance to the quantity of water used. A clear objective in husbandry should be the provision of water in a manner which takes account of these and other factors.

Both antibiotic and probiotic feed additives are in independent use in the pig industry. The modes of action of these two groups of growth-promoters remain to be established. The present study was designed to investigate the effect of inclusion of an antimicrobial feed additive (Tylosin) or a probiotic (ProbiosR, Pioneer Overseas Corporation) on growth rate and the development of intestinal structure and function of pigs from birth to 80 days of age.

Synthetic lysine and fat supplements are widely used in diets for growing pigs. However, there is evidence to suggest that free lysine is more rapidly absorbed than protein bound amino acids resulting in reduced growth performance particularly under infrequent feeding regimes. In addition, the incorporation of conventional fat supplements into cereal based diets is problematic particularly where on-farm mixing of feed is carried out. One potential solution to both these problems is to use fat coated synthetic lysine sources which have recently become available and two such materials were evaluated in this study.

Four dietary treatments were compared. These were a control diet (C) with soya bean meal as the protein supplement and diets in which 0.3 of the total lysine was supplied from either synthetic lysine (S) or synthetic lysine coated with a single (SC) or a double layer(DC) of hardened soya oil. All diets were barley based and were formulated to contain the same level of total lysine (0.01) and hardened soya oil.

Full fat rapeseed is not usually used in livestock feeds because the extracted oil is too valuable. However in some circumstances it may be worthwhile using full fat rapeseed as a protein and energy supplement. Intact seeds are only poorly digested so it is necessary to physically disrupt the seed to allow efficient digestion. Milling the seeds may allow myrosinase catalysed hydrolysis of glucosinolates yielding products which adversely affect palatability and nutritive value. Dry extrusion offers a means of simultaneously crushing the seed and denaturing the myrosinase by high temperature (130°C). Previous short term studies with rats and pigs have indicated that extrusion may improve the nutritive value of diets containing 12.5% high glucosinolate rapeseed (HG-RS).

The present work involved a production trial to study the longer term effects of diets containing 12.5% rapeseed and a metabolism study to investigate the digestion and short term effects of pig diets containing 25% rapeseed.