Pre-weaning mortality results in a national loss of about 3 million piglets annualy so a system which reared weakly or non-competitive pigs would be of value to the industry. A review of the literature concerned with very early weaning or weaning at birth showed the standards required for feeding, temperature control and hygiene to make a successful system. An apparatus designed and built to provide these standards is being tested at Terrington.

The apparatus houses 10 piglets, each in individual compartments, within a moulded glass-fibre module. A pressurised, part re-circulation fan/heater, system maintains accurate temperature control up to 34°C.

Weaning represents a critical period in the life of a piglet. Although the age at which piglets are weaned is rather variable, it is common practice to wean them at an early age. At weaning the normal pattern of growth and development is interrupted. The extent to which nutritional, climatic, social and managemental practices influences the check in growth rate and change in tissue accretion is not well documented. The present experiments were designed to investigate the influence of some of these factors on the growth and development of the weaned piglet.

In a previous experiment the wilting of herbage prior to ensiling had no effect on the efficiency of utilisation of silage for animal production. The direct-cut material was conserved with formic acid and wilting was relatively prolonged (65 h) to achieve an increase in dry matter (DM) content of 226 g DM/kg. The objective of the present experiment was to examine the effect of formic acid with direct-cut silage and the rate of wilting of herbage on losses in conservation and on energy and protein retention by growing steers.

Substituting a small proportion of barley with white fish meal has been shown to increase the daily gain cattle grown through the winter using diets based on grass silage. The object of this work was to determine iether offering fish meal during winter affected the performance of the animals at grass. The trial was made 7 farms and involved 280 cattle. They varied in live weight at the start of the trial from 140 to 370 kg. each farm there were two groups of cattle, one group was given barley and for the other group 0.25 kg/d rley was replaced by white fish meal. The cattle were weighed at the start of the trial after 90, 160 urnout) 220 and 300 days. The two latter weighings were made while the cattle were at grass.

Fish meal supplementation of grass silage diets has increased the daily live-weight gain of growing beef cattle. However, the live weight advantage at turnout has generally been negated after a period of compensatory growth at grass. Hence, protein supplementation may be economically advantageous with cattle being finished out of yards. The purpose of this experiment was to compare the effect of feeding two types of fish meal on the performance of dairy-bred cattle during the finishing winter of an eighteen-month beef system.

Treatment of straw with alkali; sodium hydroxide or ammonia, can improve both its dry matter digestibility and the amount of straw that cattle will consume. Such improvements allow straw to be used to a greater extent compared with untreated straw in rations for cattle. Several recent reports have identified however that when straw is incorporated in a ration with rapidly fermentable sources of energy, conditions in the rumen unfavourable for the bacterial degradation of straw are generated by the rapidly fermentable material, particularly at high levels of feeding. Such conditions result in inefficient utilization of the straw. It was suggested however (Williams 1984) that low level supplementation using starch, of diets high in fibre would result in an increase in intake of the roughage but that the digestibility of the material would be unaffected. The trials reported here were designed to determine whether low level supplementation of a diet of straw with either fishmeal or starch affected the degradability of fibre or the rate at which undegraded material passed out of the rumen.

Previous work has shown that treating moist grain with ‘Farmline’, a formalin acetic acid mixture, affords some protection of protein and perhaps starch from rumen degradation. A comparison with and without ‘Farmline’ treatment investigated the protection afforded to dried barley.

Experiments have demonstrated the importance of roughage to young calves in stimulating weight gain and feed intake through increased rumen buffering capacity.

Previous studies (Thomas and Hinks) have shown that weight gain and pry Matter intake were optimised with the inclusion of 220g/kg of chopped barley straw. Furthermore, the inclusion of increasing levels of barley straw in the diet were closely associated with increases in rumen pH, possibly linked with increased saliva flow, and marked changes in rumen VFA proportions. In view of the alkaline nature of ammonia-treated straw, linked with improvements in digestibility and crude protein content, further studies have been conducted to determine whether intake and weight gain might be further enhanced with the inclusion of this material in the diet.

Ammonia treatment of straw to improve its nutritive value has been widely investigated (Sundstføl and Coxworth, 1984) and techniques are now being applied commercially in many countries. Despite much research, there is a lack of experimental data collected under farm-scale conditions to demonstrate that ammoniating straw is worthwhile under United Kingdom conditions. Experiment 1 in the present study was a farm-scale trial and aimed to over-winter beef cattle at a growth rate of 0.55 kg/day, using concentrate supplements and untreated or ammonia-treated barley straw. Experiment 2 aimed to define the digestibility and intake of the straws, using wether sheep.

A further experiment in a series of trials to look at the effects of treating straws on their feed values, and the responses to different supplements was carried out in the winter of 1982-83. The treatments were:-

1. 1) Untreated barley straw (DBS) plus 1.5 kg rolled barley/urea per day

2. 2) Ammonia treated barley straw (TBS) alone

3. 3) Ammonia treated wheat straw (TWS) alone

4. 4) Ammonia treated wheat straw (TWS) plus 0.5 kg rolled barley

5. 5) Ammonia treated wheat straw (TWS) plus 0.5 kg soya bean meal

6. 6) Ammonia treated wheat straw (TWS) plus 0.25 kg rolled barley and 0.25 kg fishmeal

There were 7 Hereford x Friesian cows per treatment, all mature animals (third calvers or more) calved in May, bulled with a Charolais bull in July and calves weaned off and cows yarded in November 1982. The trial ran for 145 days from 25 November 1982 to 19 April I983 covering about months 4 to 8 of pregnancy. They were group fed.

The production of bull beef may entail year round housing and storage feeding, i.e. feeding conserved forage all year, provides a simple system and avoids dietary changes. One conserved forage used is grass silage but ammonia treated straw may be an alternative. The aim of the work reported was to compare the performance of bulls storage fed on grass silage or ammonia treated long barley straw with and without additional protein with those on a traditional system involving a summer at grass.

Some degree of wilting of grass prior to ensiling is a widespread management technique when weather conditions permit. The intention by using this technique is to both reduce the volume of effluent produced and improve silage quality. The majority of experiments suggest that there is not much benefit to silage analysis if a silage additive is used on grass that has already been wilted. However, in the case of a milking cow that is expected to consume large amounts of silage through the winter period, there could be an improvement in intake if a wilted silage was treated with an additive. The object of this experiment was to see if the use of a reliable silage additive on wilted grass led to a greater silage intake and better performance, by milking cows.

A previous trial (Brigstocke et al., 1982) had indicated that mature Jersey cows ate considerably more dry matter (DM) in relation to their body size than was currently projected from the multiple regression equations used for appetite prediction. However this trial was run on one large high-yielding herd with only a small number of animals and it was not known whether the results were applicable to the more average Jersey producer.

The results of studies undertaken outside the United Kingdom suggest that the inclusion of 50 g of 30% protected DL Methionine (Ketionin) into the ration of conventionally fed dairy cows improves feed utilisation, milk yield, fertility and health. For instance (Spørndly (1981) in Sweden measured the weight of cows during the experimental period and found that the weight loss in the control group was twice that of the cows that received Ketionin. In West Germany a significant increase in milk of 2.0 kg per day was obtained by Kaufmann and Hagemeister (1980) and similar results were reported by Kuther (1982). Stoikov (1978) in studies on 673 cows in Bulgaria showed an improvement in calving rate from 37% in the control group to 55% in the treated group and Daugaard (1978) working in Denmark reported that the inclusion of Ketionin reduced the incidence of Ketosis.

Estimates of organic matter digestibility derived from the concentration of indigestible acid detergent fibre CIADF) in the diet and the faeces compared favourably with in vivo values when a variety of forages was fed to wether sheep (Penning and Johnson, 19B3). The purpose of this trial was to evaluate IADF as an internal marker to estimate dry matter digestibility (DMD) of lactating dairy heifers fed ad libitum grass silage with one of three levels of concentrate supplementation.

Data relating to husbandry and health, from a group of 35 large dairy herds of an average herd size of around 140 cows has been collected for a number of years. Comparative analysis of the years 1978/79 and 1982/83 is presented to show the effect of calving pattern change on mastitis infections in particular, and also the effect of improved record keeping together with the need for improved efficiency on other factors such as culling and rebreeding management.

In a 2 year calving system, growth rates of at least 0.65 kg/d are required in the first winter, preferably at only moderate concentrate input levels. One potential method of increasing feed efficiency and reducing costs is to use feed additives. A trial was carried out to examine the use of two feed additives as supplements for heifer calves offered silage and concentrates.

These experiments investigated the efficacy and safety of the use of anabolic agents for finishing cull dairy cows over a two month period before slaughter. The safety of the treatment was assessed by measuring the residues of trenbolone acetate (TBA) and its metabolites in samples collected during the treatment period and at slaughter.