The effects on herbage intake of changes of herbage mass associated with different stocking rates were studied in Greyface (Border Leicester × Scottish Blackface) ewes in the autumn. Intake was measured in 5-day periods in late September (PI), late October (P2) and late November (P3) on two established, perennial ryegrass/white clover swards (SI and S2). Both swards had previously been variably stocked to produce areas with a range in herbage masses, some of which were grazed continuously (G) at stocking rates declining from 18 to 6 ewes per ha.

Intake was also measured in P2 and P3 on other areas of the swards which were ungrazed for 6 weeks in September and October (C) and then stocked at 18 ewes per ha. Intakes of dry matter, organic matter and digestible organic matter were 16 g, 10 g and 7·5 g/kg live weight, respectively. Organic matter digestibility was 075 in PI and P2 but declined in P3.

Differences in herbage intake and digestibility arose largely because of differences between the swards in herbage mass, sward height and sward density. Ewes in condition scores > 3·00 in early September had lower intakes at all times than did thinner ewes. Changes in sward management associated with different strategies of use had little long-term effect on herbage intake. Keywords: digestibility, herbage, sheep, stocking rate.

Data from 2032 Uruguayan Aberdeen Angus cows under extensive management and recording practices were analysed with Bayesian threshold-liability sire models, to assess genetic variability in calving success (CS), defined as a different binary trait for each of the second (CS2), third (CS3) and fourth (CS4) calving opportunities. Sire (herd) variances ranged from 0.08 to 0.11 (0.10 to 0.20) and heritability from 0.27 to 0.35, with large credibility intervals. Correlations between herd effects on CS at different calving opportunities were positive. Genetic correlation between CS2 and CS4 was positive (0.68), whereas those involving adjacent calving opportunities (CS2–CS3 and CS3–CS4) were negative, at −0.39 and −0.54, respectively. The residual correlation CS2–CS3 was negative (−0.32). The extent of uncertainty associated with the posterior estimates of the parameters was further evaluated through simulation, assuming different true values (−0.4, −0.2, +0.2 and +0.4) for the genetic correlations and changes in the degree of belief parameters of the inverse Wishart priors for the sire covariance matrix. Although inferences were not sharp enough, CS appears to be moderately heritable. The quality of data recording should be improved, in order to effect genetic improvement in female fertility.

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.

Preliminary studies at the Bernard Weitz Centre have shown that maize silage has the potential to increase forage intake and milk production. The trend towards earlier calving, encouraged by the Milk Marketing Board pricing policy, means that maize silage may not be available for early lactation; as most farmers rely on the current seasons crop, and few carry stocks over from the previous year. The objective of the current trial was to determine the eflect on forage intake and milk production of incorporating maize silage into grass silage based rations either from early or mid-lactation.

There is little published data on the detailed performance of continental genotypes as suckler cows in a hill environment. The work presented investigates levels of blood metabolites and hormones in autumn calving heifers during the post-partum period. Reproductive performance of the herd is detailed in an accompanying paper (Keatinge et al 1994).

In general cows have higher intakes and higher milk yields when outdoors grazing pasture compared to indoors consuming grass silage. However, this observation is not valid as a direct comparison of grass and silage due to the following reasons. Firstly, the cows consuming the silage and grass are usually at different stages of lactation and secondly the silage has not been produced from the herbage being grazed. There is little information available in the literature comparing the intakes of grass and silage harvested from the same sward at the same stage of maturity when fed to lactating dairy animals at similar stages of lactation. The present study was initiated as part of a series of studies at this Institute, to evaluate factors affecting silage intake. The main aims of this study were to determine the actual effect which ensiling “per se” had firstly on dry matter intake and secondly on animal performance by the lactating dairy cow.

A survey of dry sow housing across England (Baynes and Hunter, 1993) was conducted to assess farmers' future plans and opinions regarding the onset of the 1999 ban relating to stall and tether housing systems. Results from this survey showed that approximately one third of English pig producers currently with these types of systems were undecided as to which system to choose. A number of case studies are currently being conducted on existing group-housed systems to contribute to a data base on group housing options.

Sows were housed in a general purpose barn which had been divided into 12 pens, each housing ten sows. Sows were liquid fed once a day in a common trough with partial barriers. Total space allowance was 2.96m2/sow, of which 1.23m2 was kennelled.

Terminal Sire breeds have a considerable impact on lamb production in Britain’s stratified cross-breeding sheep industry. MLC (1988) estimated that 69% of lambs used for meat production are sired by the Terminal Sire breeds. The predominant Terminal Sire breed is the Suffolk, comprising 46% of the ram population in Britain. The genetic improvement of meat production characters has, traditionally, been difficult in this breed due to the large number of small flocks making up the breed, the restriction on AI use and the lack of a cost/effective central testing facility. However, the formation of the Suffolk Sire-Referencing Scheme Ltd (SSRS), in 1989, has provided a vehicle for faster genetic progress in the breed.

There is evidence that silage may be utilised more effectively when supplemented with sugar rather than starch (Thomas and Rae, 1988). A trial was made to measure the effect of supplementing silage with a sugar-based feed (molasses) or a starch-based feed (barley), in combination with fish meal, on the performance of young growing cattle.

Sixty four castrated male calves (Limousin x Friesian and Hereford x Friesian) initially weighing 129 kg were offered grass silage (DM, 200 g/kg; ME, 10.4 MJ/kg DM; CP, 144 g/kg DM) ad libitum with four dietary supplements.

Daily supplementation was as follows:

• 1.0.25 kg white-fish meal

• 2.0.25 kg fish meal plus 0.4 kg molasses

• 3.0.25 kg fish meal plus 0.8 kg molasses

• 4.0.25 kg fish meal plus 0.75 kg bruised barley

The levels of molasses and barley in Treatments 3 and 4 supplied the same amount of dry matter.

The ability of the gut tissues to absorb nutrients and the extent to which these are then metabolised within the gastrointestinal tract plays a central role in regulating the supply of metabolites to the liver and consequently influences the availability of nutrients for hepatic and peripheral tissue use. Energy consumption by the portal drained viscera is extensive and may account for 25% of total body oxygen consumption (Huntington and Reynolds, 1987). Substrates available for oxidative metabolism include volatile fatty acids (VFA) produced in the rumen and large intestine as addition to arterial supply of these nutrients. The aim of this experiment was to investigate the influence of increased propionate availability on metabolism of VFA in the rumen and the gastrointestinal tract.

Growing lambs are frequently subject to varying planes of nutrition. Knowledge of the response of lambs to the restoration of non-limiting feeding conditions following a period of feed restriction is necessary in order to determine economic systems for finishing lambs.

Thirty Blackface wether lambs (birth weight 3.8 kg s.d. 0.38 kg) were treated in two ways from birth to 25 kg live weight (LW). One half were reared by well-fed ewes at grass (treatment UR). The other lambs sucked poorly-fed ewes up to weaning at 18.2 kg LW (s.d. 1.9); thereafter R lambs were given 700 g/day of a high quality pelleted feed (F) to 25 kg LW. Feed F contained 158 g crude protein/kg dry matter (DM) and had an estimated metabolisable energy yield of 12.5 MJ/kg DM.

From 25kg LW both UR and R lambs had ad libitum access to feed F to a final LW of 45 kg unless slaughtered earlier. The feed intakes and LW of individual sheep were measured weekly. Six lambs from each treatment were slaughtered at 25 kg LW in order to assess the effect of treatment on body composition. Three lambs from each treatment were subsequently slaughtered at 35 kg, 40 kg and 45 kg LW. Weights of gut-fill and organs were recorded and the cold carcass (CC) dissected into lean, bone and fat.

Lameness in dairy cows has both important animal welfare and economic implications. High concentrate to silage ratios may be an important predisposing factor, whilst trimming has been advocated as an effective preventative measure. This trial examined the effects of these two factors on locomotion, incidence of lameness and hoof measurements.

Distillery products which are high in fibre have traditionally been fed only to ruminants, but might provide a cost effective feed for dry sows. If such bulky materials could be fed ad libitum, animal welfare might be enhanced by prolonging feeding time and providing the sows with a greater feeling of satiety in comparison with concentrate diets. To investigate such possibilities, voluntary intake and digestibility were determined with dry sows for three distillery products:

The three distillery products investigated were:

• 1) malt draff (MD), the barley residue remaining after starch extraction

• 2) maize curne gold (CG), evaporated spent wash plus maize cereal residue

• 3) wheat supergrains (SG), centrifuged spent wash plus wheat residue

Each material was offered ad libitum to three pens of 6 dry sows, initially in conjunction with 0.5 kg/sow/day of a balancer meal. The balancer meal contained barley (890 kg/t), limestone (100 kg/t) and a vitamin/trace element supplement at 4 times the normal inclusion rate (10 kg/t). Sows were grouped according to service date and allocated to the experimental treatments in early pregnancy. They were housed in straw bedded pens with individual stalls for feeding of the supplement. Voluntary intake, liveweight and backfat change were monitored over a minimum period of 9 weeks. Sows which failed to maintain acceptable body condition on this regime were given additional ground barley as the experiment progressed.

The cultivation and uses of trees is important and varied in many areas of the world. The benefits include soil improvement and stabilisation, shade for other plants, provision of wood and fodder for ruminant animals.

Tree leaves are important sources of micro- and macro-nutrients for ruminants in many parts of the world including Nepal and Portugal especially when other plant fodders are scarce (Topps, 1992). Thus improvements in livestock production may benefit from an increased and/or selective use of tree fodders. The proximate composition and tannin (flavanol) content of plants including tree leaves, considerably influences the nutritive value (Goodchild & McMeniman, 1991; Kumar & Vaithiyanathan, 1990; Longstaff, et al.,1991; Makkar et al 1991).

The performance of crossbred progeny of Oxford, Texel, Texel-Oxford, Charollais, Charmoise and Meatlinc terminal sires, mated with crossbred ewes, were compared.

The comparisons took place at ABRO's lowland farm in Staffordshire from 1979–1981. The crossbred ewes were by various crossing sire breeds out of a Scottish Blackface stock. Three or four six month old rams of each breed were used in each year, but 9 Texel-Oxford rams were used in 1979 and 1980. Oxford rams were used only in 1981.

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.

Dried skimmed milk (DSM) is a common constituent of piglet creep rations. Liquid skimmed milk (ISM) is considerably cheaper per unit of feed value and if it could be fed successfully to young pigs as a substitute for DSM without adversely affecting performance, significant savings could be made in weaner rearing costs.

Twenty litters from Large White x Landrace sows, totalling 199 piglets, were offered one of two creep rations.

Current strategies for sow feeding are based on maintenance of a constant body condition throughout the reproductive cycle by feeding at levels only slightly above maintenance in pregnancy and feeding generously for milk production in lactation. Recent evidence suggests that feeding at a low level during pregnancy, whilst meeting nutritional requirements, may be detrimental to sow welfare. The large intake capacity of the sow also offers opportunities for utilising cheaper, alternative feeds at this stage. If bulky feeds are available at low cost, it might be economically attractive to feed for fat deposition by the sow in pregnancy and utilise this during the subsequent lactation. This experiment was designed to investigate whether sows with increased body fat reserves at farrowing could be encouraged to utilise these efficiently during lactation by the provision of a high protein diet.