Rearing entire male calves for beef is becoming more common, but there is concern that sexual behaviour among bulls may be economically damaging and that there may be aggression between bulls and against stockmen. Behaviour has only been studied in detail in mature bulls or under disturbed conditions.

To compare the development of behaviour in stable groups of Friesian-Holstein bulls and steers prior to sale at one year old, and to assess implications for management.

Twelve bulls and 12 steers were held in an open-sided house at 5 m2/calf, with2 ad libitum hay, concentrates and water. From 5 to 10 months old, each calf was observed for one hour each month and all sexual and aggressive interactions between calves were recorded. At 6½ months, the pen was divided into halves, separating bulls and steers. This reduced the frequency of all interactions. At 10 months, reaction to humans was assessed on a scale from 1 (approach strongly) to 5 (avoid strongly). Bulls and steers were compared on all measures by the Mann-Whitney non-parametric statistical test (* = P < 0.05, ** - P <0.01).

A randomised block experiment, involving 126 British Friesian and Friesian cross beef male calves which were initially 46.7 kg and 10 days old, has been carried out to examine the effects of the quantity of milk substitute consumed per calf on the lifetime performance of calves reared for beef production. The three treatments were (1) 400 g milk powder per head daily, weaned at 6 weeks old (2) ad libitum intake of milk powder, weaned at 6 weeks (3) ad libitum intake of milk powder, weaned at 8.5 weeks. Calves on treatment 1 were bucket fed twice daily, while those on treatments 2 and 3 suckled the milk from teats. The calves were purchased in three groups in (1) October, 1983 (2) December, 1983 and (3) February, 1984. Three commercial brands of acidified milk substitute were used, one for each group. All animals were individually penned until after weaning. They were offered a pelleted concentrate, based on barley and soyabean meal, ad libitum from two weeks old until intake reached a maximum of 2.7 kg per head daily. Hay was offered ad libitum to six weeks of age and well preserved grass silage was offered ad libitum thereafter. Group 1 calves were on an 18 month grass/cereal beef system, group 2 on a 22 month grass system and group 3 on a 15 month silage/ cereal system. The chemical compositions of the milk substitutes, concentrate and silage are given in Table 1.

Parasitic gastroenteritis (PGE), largely attributable to the abomasal parasite Ostertagia ostertagi is a cause of major economic loss in the cattle industry. It has been suggested from studies on infected housed animals, together with pair fed controls, that the characteristic loss of weight occurring as a consequence of PGE is due mainly to loss of appetite, (Dargie, 1980). Thus in the present study the intention was to measure the effect of parasitism on intake under natural grazing conditions.

2 groups of 20 Freisian steer calves (175 kg at turnout), were grazed from May to September 1984 on adjacent 5 acre paddocks which had been contaminated the previous autumn by cattle Infected with 0. ostertagi. The allocation of calves to each group was such that the mean weight and range of weights within each group were similar. At turnout each calf in group A received a (Morantel slow release bolus), group B being untreated controls. The calves were weighed and sampled regularly for faecal egg counts.

Over a period of 2 years from 1982 to 1984, six feeding trials were carried out on a total of 307 Friesian bulls to investigate the effects of energy and protein levels in compound feed. All animals were fed ad-lib compound diets with free access to barley straw and water. In four of the six trials the bulls were implanted with Ralgro (zeranol, Crown Chemical Company Limited), once at the start of the trial and again after 90 days. The various dietary treatments in the different trials are given below. Theoretical undegradable dietary protein was calculated using the known degradability of raw materials in the compound feed.

Ramensin premix was launched onto the UK market in 1978 and became the first non hormonal feed additive for beef cattle.

Since that time it has become the most widely used feed additive worldwide and has been shown both by Elanco research and independent research to improve the utilisation of feed by 10%.

However, until recently the only method of administration of Romensin was via the feed or incorporated in a feed block.

At pasture, if grass is of sufficient quality, it may be unnecessary to feed a supplement thus losing the carrier for Romensin, for a large part of the summer season. During this period of time, the farmer may thus be missing out on an opportunity to achieve the optimum utilisation of feed.

As a result of recent research it may now be possible for beef producers to feed Romensin the whole year round. Romensin has been incorporated in a ruminal delivery device containing 16.5 g of monensin sodium designed to delivery 90 - 100 mg of monensin sodium daily over a period of 150 days.

Feed additives are widely used in beef production systems. Two trials were made to measure the effect of feed additives on the daily gain and feed efficiency of fattening beef cattle. In the first trial 48 Friesians and 48 weaned suckled calves weighing about 390 kg were fed individually on grass silage ad libitum together with 4 kg (Friesians) and 3 kg (weaned calves) bruised barley daily. The treatments were control (C), no additive; Avotan 150 mg/d (A); Flavomycin 45 mg/d (F) and Romensin 200 mg/d (R). Minerals and vitamins were given daily on the silage. In the second trial there were 240 Friesian and Exotic x Friesian bulls. They were housed on slats in groups of 15 and offered a mixture of bruised barley and soya bean meal ad libitum. The treatments were control, no additive; Flavomycin 50 mg/d, Romensin 210 mg/d and Salinomycin 150 mg/d. In trial 1 the steers were implanted with Ralgro and the heifers with Finaplix. No implants were used in the second trial. All the animals were weighed regularly and feed intake was recorded continuously. They were slaughtered when they achieved the required conformation and fat cover.

Results from three previous experiments with finishing cattle on an 18-month beef system indicate that the major increases in daily live-weight gain (DLG) occur within the first 50 to 60 days of supplementation with fish meal. Hence, it may be possible to remove fish meal from the diet after the initial two months of the finishing winter without any subsequent effect on animal performance.

For the last nine weeks at grass the experimental cattle were given 1.4-kg/head/day dried sugar beet pulp nuts. On housing this allowance was increased to 3.0 kg and the 48 British Friesian steers were offered grass silage ad libitum (round bale silage for one week and precision-chopped clamp silage thereafter). The 3.0-kg dried sugar beet pulp was given for five days and after a 10-day changeover period the nuts were replaced by 15-kg potatoes. Cattle were offered the basal diet of precision-chopped silage and potatoes for 12 days before starting the experiment.

Steers were implanted with 300-mg trenbolone acetate (Finaplix, Hoechst UK Ltd, Milton Keynes) and 36-mg zeranol (Ralgro, Crown Chemical Company Ltd, Lamberhurst) 20 days before randomisation.

White fish meal and feed additives are used to increase growth rate by young growing cattle in their first winter before being turned out to graze. Some evidence indicates that increased gains may not be retained through the grazing season. A trial was made to measure the effect of fish meal and feed additives, alone or in combination, on performance by young growing cattle during winter and subsequently through the grazing season. Sixty British Friesian castrated male calves were offered silage containing 220g/kg DM ad libitum. There were six dietary supplements.

Trials have previously shown that during the first 48 hours of life, new born piglets are reluctant to use forward-creep areas. In the neo-natal period, in order to prevent piglets lying in the danger-zone, luxury creep heating has been proposed. This comprises temporary heating at the rear and sides of the sow. On commercial farms, various luxury creep-heating systems are used. In an attempt to increase the precision and safety aspects of luxury creep-heating, a purpose-built device has been developed on a commercial farm. Trials were therefore undertaken, in co-operation with Eastern Electricity, to compare this system to a conventional forward-creep system.

A total of 124 litters supplied only with a 150 watt heater in the creep box (Control) was compared to 124 litters provided with the luxury regime. The supply line for the luxury device is shown diagramatically in Figure 1. It comprised a timber-mounted mains electricity power-line, temporarily suspended prior to farrowing above and behind groups of 4 sows. The line provided three 13 amp sockets for each litter and supplied a 300 watt dull-emitter located behind the sow and two 175 watt, dull emitters suspended in the side creep areas.

Many existing sow stall and tether houses, besides not conforming with the Pig Welfare Code are thermally inadequate and require major alterations. A possible alternative system, comprising loose-housed sows with rations allocated from an electronic sow feeder was evaluated.

A building comprising single-skin concrete blocks and insulated roof originally housed 74 dry sows in stalls bedded with straw. The building was gutted and re-fitted to accommodate loose-housed sows. Minimal repairs were undertaken on the concrete floor, and some new blockwork was erected, deep straw was incorporated into the new lying areas.

There is little available information on the influence of dietary energy on fat stores in the sow or on the relationship between these stores and backfat thickness measured at the P2 site. The present study was therefore designed to determine the influence of dietary energy intake in pregnancy on the fat stores of the sow after three parities including its relationship with P2 measurements taken at slaughter. In addition a comparison was made between ultrasonic measurement of P2 on the live animal and P2 measurements taken on the carcass.

There were three treatments with 15 sows per treatment which were rationed by live weight to receive approximately 30, 26, 23 MJ DE/day at 120 kg (Table 1). During lactation all sows were fed to a scale recommended by the ARC (1981) After weaning their third litter the sows were slaughtered and the left side of the carcass dissected into shoulder, ham, loin and belly joints as described by Fortin (1980). These were weighed, minced and analysed for fat content by the Folch method. P2 measurements were taken ultrasonically on the live animal, by probe on the hanging carcass and by straight measurement on the dissected loin.

Pregnant sows in poor body condition require a high feed intake to restore body fat reserves. However, a high intake in the period following conception may increase embryo losses. The first objective of this experiment was to determine whether a high feed allowance after conception has any effect on litter size compared with a normal allowance. The second objective was to investigate the effects of body condition at conception and feed rate in early pregnancy on the components of maternal gain.

Multiparous cross-bred sows of Large White and Landrace lineage were classified subjectively at farrowing according to body condition as either fat (F) or thin (T). A single diet containing 12.5 MJ DE/kg and 150 g CP/kg was fed throughout the experiment. The fat sows were fed more generously than the thin sows during the 28 day lactation with mean intakes of 5.3 and 4.8 kg/day. This was to maintain the differential in body condition between the two groups. After weaning all sows were fed 3 kg per day until mating. Within the fat and thin groups sows were allocated at random to either 4 or 2 kg of feed per day for 30 days after mating.

Welfare and building cost considerations resulted in a commercial farmer setting up a unique system of dry sow housing. Up to 400 sows are housed in a single dynamic group sharing 10 electronic feeding stations.

Recently, sow-activated electronic concentrate dispensers allowing dry sows to be group-housed and individually fed have been seriously considered as an alternative to the close confinement of pregnant sows. For the system to be economic, each feeding unit needs to be used to its maximum potential, while at the same time considering the well-being of the animals.

Previous work has established that levels of aggression may be minimised within a set group size and the maximum number of sows per feeder may be increased to over 30 by feeding only once per day on this system (Lambert et al., 1985). With groups of this size, the practical aspects of large group management need to be considered.

Sows kept outdoors are traditionally fed a compound diet, in the form of a-large biscuit, which is spread on the ground over a wide area to try to minimise bullying. They can be kept in several separate groups, divided by electric fencing, each group containing sows at a similar stage of pregnancy. The use of a computer controlled feeder would allow the sows to be kept as one dynamic group and allow food intake to be controlled on an individual or group basis. Also, normal pelleted food can be used in such a machine. Bulky feeds are playing an increasing role in the diet of outdoor sows, and it was decided to investigate the use of an electronically controlled feeder to supply a compound feed to balance grazed fodder beet.

A single injection of 400 i.μ. pregnant mare's serum gonadotrophin (PMSG) plus 200 i.μ. human chorionic gonadotrophin (HCG) has been shown to induce puberty in a high proportion of gilts treated (Burnett and Walker, 198S). However, studies indicate that the hormone treatment may fail to initiate normal oestrous cycling after the pubertal ovulation. The work of Paterson and Lindsay (1981) has shown that housing gilts in contact with boars throughout the cycle after puberty induction will enhance the proportion of animals which maintain cyclic activity to a second ovulation. The purpose of the experiment reported here was to examine the effect of boar contact and the timing of the introduction of boar contact on the maintenance of cyclic activity after puberty induction by PMSG + HCG.

Vasectomised boars are already in use on some commercial farms for detecting and synchronising oestrus, especially in gilts. Increasing the number of matings a sow receives during oestrus has been found to increase subsequent litter size and conception rate (Reed 1982, Tilton and Cole 1982). If vaginal-uterine stimulation is the underlying cause for this reproductive improvement, then similar effects should be possible using vasectomised boars.

A total of 200 Large White/Landrace cross sows were weaned at 4 to 5 weeks and housed adjacent to mature fertile boar where physical contact was possible through a barred gate. The sows were inspected for signs of oestrus each morning and, if receptive, were given a single mating with a fertile boar. Approximately 3 hours later, alternate sows were penned with a vasectomised boar and one service was supervised. These sows remained with the vasectomised boar overnight and were then remated with the original boar. The control sows were also remated with a fertile boar, 24 hours after the first service.

From weaning to service all sows were offered 2.7 kg of a 155 g/kg crude protein, barley based sow nut. After service this was reduced to 2.2 kg per day.

Dried skimmed milk (DSM) is a common constituent of piglet creep rations. Dried whey and whey products are however increasing in popularity, mainly due to their lower cost.

To compare these two milk products, twenty litters from Large White x Landrace sows, totalling 188 piglets, were offered one of two creep rations.

The use of drinking water as a vehicle for the medication of early weaned pigs offers an advantage over infeed medication in that water intake postweaning is substantially higher than feed intake. A precondition for effective water medication is the accurate assessment of water intake. At present there is little published information on the water demand of early weaned piglets reared under contemporary conditions of housing and nutrition. The objective of this study was to establish whether the water intake of early weaned piglets could be predicted from easily measured variables such as feed intake and liveweight.

Preweaning mortality generally accounts for 10-20% of all piglets born alive. A better understanding of the reasons for this mortality should help reduce losses.

Data from 493 litters born over a period of 18 months were analysed to investigate the timing, apparent cause and predisposing factors of piglet mortality.

To examine in more detail the way in which deaths occur a continuous video recording was made for the first 48 h. after farrowing for 31 litters. The way in which any deaths happened and the events leading up to them were then examined in detail.