There is an increasing interest in the production of grass silage in big bales. As with the making of silage in clamps, there is scope for considerable loss of effluent which results in a reduction in nutritive value of silage in addition to possible effects on environmental pollution.

Molassed sugar beet feed (MSBF) has been used as an absorbent in the production of clamp silage. Additional benefits may accrue from an improved silage fermentation as a consequence of the presence of readily fermentable carbohydrate in molasses contained in MSBF. In turn, an improvement in fermentation may lead to better intake and utilization of the silage by ruminant animals.

This project was carried out to assess the effect of inclusion of MSBF, at two different levels, with grass at ensiling on the nutritive value of big-bale silage and on animal performance. The results on animal performance were compared with those obtained from offering a similar amount of MSBF pellets as a supplement to silage given alone.

The use of malt distillers grains (draff) in ruminant diets is limited both by its moderate digestibility and variable intake. This is due to the low digestibility of its fibre and to the inhibitory effects of its unsaturated oil on rumen cellulolysis. Treatment of draff with Ca(OH)2 may ameliorate these limitations in two ways. Firstly, alkali treatment increases fibre digestibility due to hydrolysis of lignocellulosic linkages. Secondly, under alkaline conditions and in the presence of calcium ions, the unsaturated fatty acids of the draff oil form insoluble calcium soaps, thus reducing their inhibitory effects on rumen function.

Thirty Blackface-cross lambs were allocated by sex and weight to three groups of ten. The animals were penned in pairs and were offered hay ad libitum and supplemented with 350g DM/d of either mineralised draff (MD), limed draff (LD - draff treated with 80g Ca(OH)2 /kg DM, held at 60°C for 18 hours and then dried at 60°C), or a proprietary lamb finishing concentrate (C - Premium Sheep Fattening Pellets, Carrs Farm Foods, Solway Mills, Silloth). The supplements were gradually increased to 1200g DM/d over 60 days. Dry matter intakes of hay and supplements were measured daily and animals were weighed weekly. The lambs were condition scored ‘blind’ on day 60 and were assessed for slaughter.

Premature loss of wool from fleece casting prior to shearing is a problem in some sheep genotypes, in particular in the North Country Cheviot. The reasons for this ocurrence are not fully understood, but it is believed that it is due to a complex of factors including heredity, nutritional and managerial (stress) practices, the wool growth cycle, and physiological parameters such as pregnancy. Prolonged stress is reported to be particularly important in the case of wool slip in ewes which are housed and shorn (Morgan et al, 1986).

The present study aimed to investigate the incidence of visible fleece casting in the North Country Cheviot (NCC), Scotch Halfbred (HB) (Border Leicester x NCC), and Border Leicester (BL), which has no history of premature wool loss. The study was implemented on 8 commercial farms in Scotland, and links between key productive parameters and wool loss were studied, and an attempt to identify fleece types most liable to cast was also made.

The Highlands and Islands Development Board (HIDB) is developing a strategy for the production and marketing of high health breeding sheep. With HIDB support, farmers in the North of Scotland have formed a co-operative to produce and market high health status sheep. The co-op (the Highlands and Islands Sheep Health Association) has over 800 members with a total of 300,000 breeding ewes. Members' flocks are monitored by the Scottish Veterinary Investigation Service for Enzootic Abortion of Ewes (EAE) and for vaccination against the Clostridial Diseases and Pasteurella. To guide HIDB strategy a postal survey was undertaken of lowground breeding sheep purchasers in Grampian and Borders.

The objectives were to determine, firstly, lowground breeding sheep purchasers' attitudes, opinions and practices when buying breeding sheep; secondly, their management of sheep health; thirdly, their experience of EAE, its prevention and control; and fourthly, their awareness of sheep health schemes and interest in purchasing high health status sheep.

The profitable management of milk production in relation to quota would be greatly aided by an ability to predict responses in milk constituent output to changes in feeding. One pre-requisite for doing so is a knowledge of substitution rates between feeds. The trials described here were the first in a series to aid the development of a mathematical model embracing the inter-relationships between forage quality and type, concentrate level and type, and milk outputs. The objective was to explore further the impact of silage type and quality and a wide range of concentrate level on substitution rate and milk constituent output.

Silage effluent represents a potential pollutant and a loss of ensiled nutrients. An absorbent provides the possibility of absorbing effluent, aiding fermentation and increasing the feeding value of the silage. Sugar beet pulp (SBP) nuts and rolled barley (RB) were evaluated as absorbents with direct cut grass silage.

Perennial ryegrass swards of 222 g/kg average dry matter were direct cut between 10 and 12 July 1989. Grass was ensiled with the following rates of absorbent per tonne of fresh material:

1. 1. 20 kg SBP (S20).

2. 2. 40 kg SBP (S40).

3. 3. 40 kg RB (B40).

4. 4. Untreated (U).

Production of silage effluent was measured with a tippler mechanism attached to an electronic logger and recorded daily until 22 September. The silages were individually fed through Calan Broadbent doors to 48 x 12 month old Friesian steers between 24 October and 19 December.

Postponing the cutting date increases the yield of grass silage but at the expense of reduced quality. A means of improving the quality of later-cut silage would clearly be of major benefit. One possible approach is to improve the digestibility of later-cut silage by treatment with enzymes. The purpose of the present experiment was to examine the effectiveness of a cocktail of enzymes based on cellulases and hemicellulases (FinnFeeds Ltd, Redhill, Surrey).

Including dry feed materials (absorbents) with grass at ensiling has been shown to reduce effluent output and improve silage fermentation (Offer and Al-Rwidah, 1989) although the effects of this practice on animal performance have been somewhat variable (Ferris and Mayne, 1990; Jones, Jones and Moseley, 1990). However little is known about the fate of these absorbents during ensilage or the effects of ensiling upon their chemical composition. The aim of this investigation, which was part of a large scale dairy cow production study was to examine the nutrient recovery and compositional changes occurring with unmolassed sugar-beet pulp (SBP) when ensiled with grass at three levels of inclusion.

The trial is one of a series in a project to develop a mathematical model to predict the consequences of changes to the food supply on yields of milk constituents. The objective of the trial was to measure the responses of winter-calved dairy cows to changes to the level or to the distribution within a level of concentrates given with grass silage ad libitum.

Ninety-eight British Friesian cows in their second or subsequent lactations with a mean calving date 6 December were used in a randomised block experiment. There were 7 treatment groups. Cows received on average 3, 6 or 9 kg concentrate dry matter (DM) per day over weeks 4 to 22 of lactation.

Supplementation with Yea-sacc - yeast (Saccharomyces cerivisiae ‘1026’) and its growth medium or with Avotan - an antibiotic feed additive has been found by several workers to alter rumen fermentation patterns and animal performance. This experiment investigated the effect of inclusion of these supplements on their own or in combination in the concentrates of silage fed steers on rumen fermentation and animal performance.

Silage effluent is a major contributor to farm pollution incidents in the United Kingdom. In 1987, silage effluent was responsible for 26% of all farm pollution cases reported, and 437. Of farm associated water pollution incidents that resulted in prosecution.

A practical solution to this problem could be to incorporate absorbent materials into the grass at ensiling. Several absorbent materials have been tested, some being based on fibrous bi-products. Of those tested, chopped barley straws proved the most effective (Offer an Al-Rwidah 1989) however this material lowered silage quality and also reduced the weight of grass that could be stored in a given silo by 78%. Molassed sugarbeet feed (MSBF), a feed high in digestible fibre which has been widely incorporated into ruminant diets as an energy source, was less absorbent but improved silage quality and reduced grass storage weight for a given silo by only 27%.

Environmental pressures on the agricultural industry to reduce the use of nitrogenous fertilizer, coupled with the improvement and availability of varieties have led to renewed interest in white clover for dairy systems in the UK. In addition clover has nutritional merit as a supplement to grass which can lead to increased forage intakes and improved subsequent animal performance. In this experiment two silages of perennial ryegrass and white clover Here fed to autumn calving dairy cows in varying ratios to evaluate white clover as a forage supplement for cows fed low levels of compound.

Supplementary forage is frequently fed to grazing cows to overcome pasture shortages. It is particularly Important for cows grazing a high clover Sward because of the need to maintain a short sward that will encourage high clover contents. This experiment compared high clover and high ryegrass silages and hay as supplements for cows grazing high clover or high ryegrass pastures.

Previous research has suggested that ruminants will select a high Na diet possibly even when they are not Na deficient (Chiy and Phillips, 1991; Michell and Moss, 1988). Schneider et al (1986) also recorded an increased DM intake of dairy cows up to 5.5gNa/kg dietary DM. increases in ruminating time have also been recorded for high Na diets (Chiy and Phillips, 1991) but it is unclear whether this arises from increased herbage intake. This experiment aimed to further investigate the effects of Na content of feed on ingestive behaviour of dairy cows.

The U.K. Milk Marketing Boards are encouraging dairy farmers to produce more milk in the summer months. However, the management of May to July calving cows is difficult as peak yield and intake requirement coincide with declining grass growth and quality. One means of overcoming this problem has been to offer a forage buffer as an extra feed to supplement the intake of grazed grass. The objective of this experiment was to investigate optimising the performance of summer calving cows by manipulating grass sward morphology to improve grazing intakes and eliminate the need for a forage buffer.

Much of coastal Kenya has a subhumid lowland climate with proven potential for small holder dairy production. Establishment of dairy units to realise this potential is taking place and is being stimulated by a large unsatisfied demand for milk and dairy products. The units use crossbred cows with the recommendation that feeding is zero-grazing based on Napier fodder (Pennisetum purpureum). Napier fodder usually contains insufficient protein to meet the requirements of lactating animals so there is a need to feed a by-product or forage which is rich in protein. The legume shrub Leucaena leucocephala grows well in the subhumid tropics and it has been established already on many smallholder farms. The aim of this study was to compare the performance of lactating dairy cows given Napier fodder only cut at two different stages of growth (1.0 or 1.5 m in height) or supplemented at two levels with freshly cut Leucaena.

A majority of cows calve during the autumn months, resulting in a deficit in milk supplies to creameries during late summer and a surplus in winter. To improve the efficient and economical working of creameries the Milk Marketing Board has revised its strategy of manipulating the seasonal milk price to encourage the movement of 200,000 calvings within three years to the summer months (late May to July). From 1989, the first year of the new strategy, there has been a 21-30% increase in the price of milk delivered during July to October; providing a considerable incentive to produce more milk during this period with potentially higher financial returns from summer compared to autumn calving herds.

The diets for growing-fattening bulls in Belgium are usually high in concentrate (Van Eenaeme, Istasse, Gabriel, Clinquart, Maghuin Register and Bienfait, 1990). The fat content of such diets in usually low at about 0.025. Over the recent years, feed manufacturers have incorporated fat in fattening diets. The incorporation rates are usually rather low so that the ether extract content is about 0.05 in fat supplemented regimes. At such rates upsets of intake and digestion and depression of growth could be avoided (Zinn, 1989). The fat concentrates which are incorporated are usually blends of various and very often unknown origins. Conflicting observations were reported on the effects of fat supplementation. Two experiments were carried out to assess the effects of soya oil on metabolism in the rumen and on apparent digestibility.

Soya oil at an inclusion rate of 33 g/kg in a concentrate diet for growing-fattening bulls tended to increase the production of volatile fatty acids and the dry matter disappearance from nylon bags incubated in the rumen. It also slightly improved apparent digestibility of dry matter, organic matter and fiber and significantly increased the ether extract digestibility (Clinquart, Van Eenaeme, Istasse, Neirinck, Midy and Bienfait, 1991). It was therefore interesting to assess the effects of soya oil supplementation on animal performance. The linoleic acid content of soya oil is about 0.50. Such fat could be used to increase the unsaturated fatty acid proportion in order to produce a more dietetic fat.

Cattle not fed a supplement on dry season grazing lose weight. The magnitude of this loss and the extent of recovery during the subsequent wet season were measured in Mashona steers.

Mashona steers aged 8 and 20 months at the outset (groups A and B respectively) were used. Within each group (n = 50) steers were fed cottonseed meal (CSM, 250g per 100kg live-weight) or not fed CSM during the dry season.