The effect of quebracho tannin (QT) on the activities of rumen microbes was studied both in vivo and in vitro. The in vivo study was carried out in four rumen environments created by feeding four fistulated sheep a basal diet of chopped grass hay, grass cubes and whole barley (control) with or without the addition of QT and the dietary modifier Browse Plus (BP). The active ingredients in BP are polyethylene glycol (PEG, more than 0·95 of the dry material), polyvinyI pyrrolidone (PVP) and calcium hydroxide. The diets offered were control, control plus 50 g QT per kg diet (CQT), control plus 50 g QT per kg and 0·1 (CQT+ 0·1) or 1.0 g BP per kg (CQT + 1·0). The experiment was a 4 X 4 Latin-square design with periods of 4 weeks. Rumen liquor samples were collected at 0, 2, and 8 h after feeding, 18 and 25 days after commencement of each period. Changes in free and bound proanthocyanidin (PA) concentrations, rumen pH, ammonia, volatile fatty acids (VFA), soluble protein concentrations, particle-bound cellulase and xylanase activities and rumen protozoal counts were used as indices of microbial activities. The same diets were incubated with rumen contents in vitro, except that the 0.1 g/kg level of BP was replaced by a fourth treatment made up of control plus 1·0 g BP per kg DM of hay (CBP). In vivo, bound PA concentrations in the rumen liquor of all the sheep given QT-containing diets were higher than those of the free PAs. The bound PA was higher (V < 0·05) in the rumen liquor of sheep given CQT in comparison with those containing BP. There were reductions in ammonia (P > 0·05), soluble protein (P < 0·05) and total VFA (P > 0·05) concentrations in the rumen liquor of sheep given CQT in comparison with those given the control and BP-containing diets. Reductions (P > 0·05) were also observed in the cellulase and xylanase activities of the rumen microbes and in protozoal counts (P < 0·05) in the presence of QT in the diet. In vitro, QT reduced (P > 0·05) the viable bacterial counts, gas production and the total VFA concentrations after incubation. In both the in vivo and in vitro experiments, BP was able to alleviate some but not all of the depression in microbial activities. The main constituent (PEG) in BP binds to some of the tannins in solution and may displace tannins from tannin-protein complexes.

Three groups of five male pigs (boars) were reared from an early age under various social conditions. The sexual and social behaviour of the boars was studied from 31 to 56 weeks of age. Boars individually reared from 3 to 12 weeks of age in adjacent wire-mesh pens had similar copulatory performance to that of group-reared boars. However, an apparently important component of courting behaviour, ‘nosing activity’, was significantly reduced (P<0·05) amongst those boars individually reared from 3 weeks of age in adjacent wire-mesh pens. Social behaviour appeared to be unaffected by the rearing treatment.

A randomized block experiment, using 30 British Friesian cows, was used to assess the effects of offering supplements containing 172 and 234 g crude protein per kg dry matter in addition to grass silage which had a very high digestible organic matter in the dry matter of 769 g/kg. The animals, which had a mean calving date of 1 February, were blocked according to calving date and lactation number and allocated at random within each block to the two treatments. The treatments were applied from day 8 of lactation until the animals went to pasture on 13 April and both supplements were offered at the same rate of 7·6 kg per day. The total yields of milk produced during the experimental period were 1626 and 1650 ±38·4 kg and the mean daily yields during the final week were 24·8 and 25·6 ± 0·58kg for the medium and high protein supplements respectively. The mean live weights for the two groups were 524 and 544 ± 5·5 kg, and body condition score 2·9 and 3·3 ± 0·34 for the medium and high protein supplements respectively at the end of the treatment period. No significant treatment effects on milk composition were recorded at any stage during the experiment. Analysis of blood samples taken during the final week of the experiment showed plasma urea levels, at 220 and 290± 18 mg/1 for the medium and high protein supplements respectively, to be significantly different.

Improvement in body condition and carcass traits through nutritional intervention was studied in cull ewes. Sixty-eight adult non-productive Malpura ewes (average body weight 26.7 ± 0.33 kg) were randomly divided into four equal groups: G0 maintained on free grazing for 8 h on protected natural rangeland with ad libitum guar (Cyamopsis tetragonoloba) straw (GS) after grazing; G1, G2 and G3 fed with supplemental concentrate at the rate of 250 g, 2.5% of live weight (LW) and ad libitum, respectively. The experiment was continued for 90 days and daily feed intake, weekly LW and body condition score (BCS) were recorded. Intake and digestibility of nutrients were assessed by indicator method. Rumen fermentation attributes and blood biochemical profile were studied to assess the dietary effects and animals were slaughtered at the end of experiment for evaluation of carcass characteristics. Higher dry matter (DM) intake and improvement in plane of nutrition was observed in G2 and G3 with a higher LW gain (LWG) and improvement in BCS than in G0. The digestibility of DM, organic matter, CP, ADF and cellulose was higher (P < 0.05) in G2 and G3 than in G0. A lower ruminal pH and ammonia N but higher total N and trichloroacetic acid-precipitable N, an increase in holotrichs, spirotrichs and total protozoa population, increase in haemoglobin but decrease in serum total cholesterol and non-esterified fatty acids were observed in high-concentrate-fed groups. Carcass attributes revealed increase (P < 0.05) in empty LW, dressing yield, eye muscle area, subcutaneous and intramuscular fat, decrease in shear force value and higher (P < 0.05) protein content in Longissimus dorsi muscle in test groups than in the control. Above all, the G2 animals had better rumen environment and blood biochemical attributes and consumed more feed with enhanced digestibility that supported higher LWG at better feed conversion efficiency, improvement in BCS and carcass quality. Thus, re-alimentation of cull ewes with challenged feeding of concentrate at 2.5% of LW on a basal roughage diet for a period of 3 months may have promise for better economic return to the farmers with possibly meeting quality mutton for human consumption.

A study was made of the wool production of 490 females and 137 males of a strain of French Angora rabbit. The female adults weighed 4107 g and produced 249 g of wool every 14 weeks. Production was low for the first harvest (35 g) which consisted mainly of short wool. It then increased rapidly (203 g for the third harvest). After the third harvest, three-quarters of long wool was also bristly. The length of bristles (102 mm) decreased by 4 mm, and that of downs (62 mm) increased by 3 mm when the harvest number went from two to four. The coefficient of correlation between wool production and live weight was lower than 0·30. Adult females born in autumn produced 16 g more than those born in summer. Wool production was at a maximum during autumn and winter harvests and at a minimum in summer.

Winter fleeces had longer bristles and down than summer ones. Males produced well wool than females. When a female dropped a litter, her wool production decreases by proportionately 0·1 to 0·2. Bristly fleeces were clearly different from woolly fleeces on account of higher weight, homogeneity and compression. Objective criteria to evaluate tautness will have to found.

Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main objective was to investigate feather eating and its association with plumage damage and floor feather characteristics in commercial flocks of layers in barn and organic production systems. The study was performed in 13 flocks of barn layers and 17 flocks of organic layers. Each flock was visited at around 32 and 62 weeks of age. During both visits, the plumage condition was assessed and the density of floor feathers recorded. In week 62, droppings and floor feathers were collected. Droppings were examined for presence of feather content, whereas length, downiness and pecking damage were recorded for each floor feather. In week 62, a higher prevalence of hens with poor plumage condition was found in barn (22.2%) compared with organic production systems (7.4%; P<0.001), but the prevalence of droppings with feather content did not differ between the two production systems (8.5% in barn v. 4.3% in organic; P=0.99). Our hypothesis about a positive correlation between feather eating and plumage damage was not supported as no correlation was found between the prevalence of poor plumage condition and the prevalence of droppings with feather content. However, the prevalence of pecking damaged floor feathers was positively correlated both with prevalence of droppings with feather content (P<0.05) and poor plumage condition (P<0.01), indicating a possible association between feather eating and feather pecking. In conclusion, it was confirmed that feather eating occurs on-farm, but feather eating was only found to be positively correlated to the number of floor feathers with pecking damage and not as expected to the prevalence of plumage damage. More research is needed into the sources from where feathers are selected for ingestion, that is, whether they are picked from the floor litter, plucked directly from other hens or dislodged during preening of own feathers.

The growth and carcass characteristics of autumn-born Hereford × Ayrshire castrated male calves reared on two planes of nutrition have been studied. Restricted feeding for 12 weeks after weaning from liquid feed to the time the calves were turned out to grass created a difference of 52·0 lb per head in live-weight gain and 15·2 lb of this difference persisted at slaughter. There were small differences in carcass conformation and composition.

Genetic parameters for dystocia in the Main-Anjou breed were estimated. Data consisted of 28 178 birth records collected between 1978 and 1989 in 995 herds, with 161, 71 and 12 415 sires, maternal grandsires and dams, respectively, represented. Original scores (1 through 5) were collapsed in order to set two dystocia definitions: dystocia 1 (scores 1+2 v. 3+4+5) and dystocia 2 (scores 1 v. 2+3+4+5). Four models were proposed for genetic parameter estimation: (1) fixed effects plus sire effects; (2) model 1 plus maternal grandsire effect; (3) model 2 plus dam within maternal grandsire effects; (4) same as model 3 but a random effect ‘herds’ replaced a fixed effect ‘regions’. Two methods of fitting models were applied: marginal maximum likelihood and the ‘tilde-hat’ approach. Estimates of genetic parameters by the two methods were similar. Models ignoring maternal effects overestimated the heritability of direct effects especially in the case of dystocia 2. Dystocia definition was responsible for the greatest difference among estimated genetic parameters. Possible reasons for this are discussed. When analysing large data sets, it is recommended judiciously to collapse dystocia categories and to apply approximate statistical procedures to complete models including maternal effects.

Transport and accompanying mixing of pigs causes fights among pigs and stress resulting in decreased welfare and reduced meat quality. This study investigates the effect of toys available during transport and lairage on behaviour, stress responses, and meat quality of slaughter pigs. Cross-bred (Piétrain×Hypor) pigs (109·1±10·1 kg) were allocated to one of three treatments during transport and lairage: 1) no toys (control) 2) rubber toys and 3) balls. The rubber toy consisted of two fixed rubber sticks; the plastic ball was filled with pieces of maize, which became available for the pigs in small amounts by manipulating the ball. Per group of 11 pigs, two toys were provided. Totally, divided over 4 replicates, 144 pigs were involved, of which 72 were used for blood sampling and meat quality measurements. Five minutes scans during lairage revealed that treatment did not affect the percentage of pigs that lay (P=0·20), stood (P=0·83) or sat (P=0·12) and that in almost all scans at least one pigs was manipulating a ball, compared with half of the scans in which at least one animal was manipulating a rubber toy (P=0·02). However both toys resulted in a lower incidence of shoulder lesions compared with the control group (P=0·06; 31·1% and 28·9% of the pigs for the rubber toys and balls respectively, versus 51·1% for the control group). Blood sampling at sticking showed that pigs with the balls during transport and lairage tended to have lower cortisol concentrations (P=0·07) than pigs with the rubber toys. Also, a decrease in plasma lactate concentration was observed for these pigs in comparison with the control group (P=0·08), and a higher pH of the m. longissimus dorsi 45 min post mortem for the pigs with the balls was found than for the pigs with the rubber toys (P=0·01). These results indicate that enrichment of compartments during transport and lairage with balls reduced glycolysis in muscle resulting in a lower lactate production and a slower pH decline. The pH 45 min post mortem of the m. biceps femoris and the pH, electrical conductivity, colour, and water-holding capacity of the loin 48 h post mortem were not affected by treatment. In conclusion, environmental enrichment with toys during transport and lairage can decrease shoulder lesions and lower the pH decline 45 min post mortem, especially by provision of plastic balls filled with maize.

Wild red deer (Cervus elaphus) hinds were subjected to one of five post-capture management strategies during the period from capture in late pregnancy in March, until weaning in September. The treatments were: remained enclosed at the capture site; relocated to a remote site; relocated to a conventional deer farm on improved pasture; relocated to a conventional deer farm and grazed with farmed hinds; housed prior to calving on a conventional deer farm site. For a further year, all hinds were managed under conventional deer farm conditions. There was considerable evidence, based on mortality and behaviour, to suggest that initial housing of the hinds following capture compromised their welfare. Deaths of hinds (seven out of 20) occurred in this group, associated with bullying during the housed period. Hinds on this treatment also showed a higher frequency of aggressive interactions compared with the groups directly moved to the deer farm (11% v. 2% respectively of scans conducted at 10-min intervals over 6h; P < 0·001) and a reduced level of lying behaviour (15% v. 34 to 47% of scans; P < 0·001) during the gestation period. Similarly, during the calving period, this group lay the least (27% v. 43 to 72% of scans; P < 0·001) and the mean number of interactions between hinds reached 11·7 compared with 1·5 to 4·9 (F < 0·001) in the other groups over a continuous 6-h recording period. The two groups of hinds relocated directly onto sown swards were generally similar to one another in terms of behaviour and performance. However, the group mixed with farmed hinds suffered from considerable calf losses in year 1 due to disease (four out of 12). Losses of hinds over winter in year 1 (nine out of 90) occurred principally amongst those animals which had not become habituated to human presence or supplementary feeding in the summer, i.e. groups remaining enclosed at the capture site or relocated to a remote site. When all hinds were treated similarly in year 2 the hinds from these same two groups, together with those initially housed indoors, showed more hind-hind interactions overall than the two groups located directly onto the deer farm (7·2 v. 3·1 interactions per hind over a 4-h period; P < 0·02) and it is suggested that these hinds had not yet adapted to their new environment. An ACTH stimulation test conducted during year 2 supported the view that the two groups of hinds most recently introduced into the managed system were subject to a chronic stressor at the time of testing, since administration of ACTH did not elicit a significant increase in plasma cortisol concentrations (mean values pre- and post-ACTH 188 and 217 nmol/l respectively). In contrast, the mean plasma cortisol concentrations of the two groups managed under extensive farm conditions from the outset, showed a significant rise (pre- and post-ACTH, 261 and 376 nmol/l respectively; P < 0·01). From this it is concluded that their adaptation to the farm environment had already occurred. The live-weight gains of the wild hinds calves (229 g/day) on the improved pastures in the 1st year of the study were below that for farmed hinds calves (282 g/day; P < 0·05), suggesting that they were not habituated to the management system. However, by the end of year 2 animal performance was comparable with that of farmed hinds and calf growth rates reached 276 g/day. Thus while housing wild red deer immediately after capture is associated with poor welfare, analysis of behaviour, adrenal response and animal production over a longer period suggests that by the end of the study few important differences remained between the groups.

Factor analysis was applied to individual type traits (TT) scored in primiparous cows belonging to two dual purpose Italian breeds, Rendena (REN; 20 individual type traits evaluated on 11 399 first parity cows), and Aosta Red Pied (ARP; 22 individual type traits evaluated on 36 168 primiparous cows). Six common latent factors (F1 to F6; eigenvalues ⩾1) which explained 63% (REN) and 58% (ARP) of the total variance were obtained. F1 included TT mainly related to muscularity, and F2 to body size. The F3 and F4 accounted for udder size and conformation, respectively. F5 included rear legs and feet. Biological significance for F6 was not readily obtained. Moderate to low heritability were estimated through REML single-trait analysis from factor scores (from 0.22 to 0.52 in REN, and from 0.08 to 0.37 in ARP). The greatest heritability values were estimated for body size and muscularity (0.52 and 0.37 for body size; and 0.40 and 0.32 for muscularity in REN and ARP, respectively). As expected, rank correlations, obtained considering estimated breeding values derived from best linear unbiased prediction analysis on the individual TT and factor score, showed similar coefficients to those observed in the factor analysis following loading of TT within each latent factor. These results suggest the possibility to implement the factor analysis in the morphological evaluation, simplifying the information given by the type traits into new variables useful for the genetic improvement of dual purpose cattle.

1. In a comparative slaughter experiment, 12 female pigs (six at 80 kg and six at 100 kg) were allocated at first oestrus to each of five treatments: Treatment 1, initial slaughter, or Treatments 2, 3 and 4, mated and given 19·5, 25·8 or 32·1 MJ ME/day for the last 100 days of pregnancy, or Treatment 5, not mated (virgin) and given 25·8 MJ ME/day over a similar period. Pigs on Treatments 2, 3, 4 and 5 were given the same amount of protein and were killed about 123 days after first oestrus. Piglets were removed at birth.

2. There was no evidence of any special effect of pregnancy in the stimulation of permanent maternal growth. The average live weight, ingesta-free body and carcass gains of the pair-fed, mated and virgin gilts (±SE of difference) were, respectively, 32·3 and 36·9 + 2·8, 27·5 and 27·6 ± 3·4, and 26·0 and 26·7 + 2·1 kg. There were no statistically significant differences between these two treatments in carcass composition, specific gravity or backfat thickness. The mated pigs had lighter livers (P < 0·01) and heavier reproductive tracts (P < 0·05), and lost about 9 kg within a week of parturition.

3. Increasing energy intake increased piglet birth weights (P<005) but had no effect on the number of piglets born. The pigs that were initially heavier (100 kg v. 80 kg) had 1·5 more piglets, though this was not statistically significant (P<0·1).

4. Although there was no special effect of pregnancy on permanent maternal growth, the conversion of food by the once-mated pig was very efficient if an allowance was made for the food cost of producing the piglets.

Designs testing clones in a closed nucleus, in which 1024 cows are tested each year, were compared for their additive genetic response to selection (genetic response) and their genetic superiority of female genotype(s) selected for commercial cloning (clonal response), using stochastic simulation. Clones were tested at the expense of dam or sire families, matings per dam (sire), or full-sibs per family. The reference design maximized the genetic response corrected for inbreeding in the absence of cloning. The trait considered was overall economic merit for milk production, which was simulated assuming an approximate infinitesimal model with both additive and dominant gene action. Bulls and cows eligible for breeding were selected on their animal model estimated additive genetic effect at either 15 or 27 months of age. Female genotypes eligible for commercial cloning were selected on their estimated total genetic effect at 27 months of age. All (fe)male full-sibs were available for selection. With only additive gene action, testing clones at the expense of sire families, matings per dam or full-sibs per family reduced genetic response, while it increased clonal response and inbreeding. Testing clones at the expense of dam families, however, added to both the genetic and clonal response without increasing inbreeding. When eight clones were tested at the expense of dam families, the genetic response and the final genetic level of commercially available cloned embryos were maximal. Accuracy of clonal selection equalled 0·83. With dominant gene action, however, testing two clones at the expense of dam families maximized the final genetic level of cloned embryos, irrespective of the level of inbreeding depression (accuracy of 0·72). Reliable commercial clone lines can be produced now and in future generations by testing clones at the expense of dam families.

Four experiments examined the chemical composition, intake, dry matter (DDM) and organic matter (DOM) apparent digestibilities and rates of disappearance from nylon bags of hand-separated leaf and stem fractions of straw from four genotypes of barley: Arabi Abiad, Beecher, C63 and ER/Apam. In experiment 1, 900 g leaf from each genotype was offered to three or four wethers together with 200 g soya-bean meal (SBM), and in experiment 2 the leaf from the same four genotypes was offered ad libitum with 200 g SBM. In experiment 3, 500 g stem from Arabi Abiad and Beecher was offered with 100 g SBM to six wethers in two groups. Experiment 4 measured the rate and extent of disappearance of the leaf and stem fractions from nylon bags incubated in the rumen of wethers. The genotypes had widely contrasting morphological characteristics. Stems contained about half as much ash and crude protein as leaves and differences within fractions were small. The leaf and stem fractions of the two-rowed barleys Abiad and Apam contained less modified acid-detergent fibre than the six-rowed Beecher and C63 genotypes.

When leaf was offered with SBM, both restrictedly and ad libitum, the DDM and DOM of this fraction were similar between genotypes (P > 0·05) and in experiment 2 the intake of leaf was also similar between genotypes (P > 0·05). The apparent digestibility of stem differed significantly between Arabi Abiad and Beecher in experiment 3 (P < 0·05). Significant differences were apparent between genotypes in the extent and rate of disappearance of leaf and stem from nylon bags after 48 h incubation in the rumen.

Five hundred and eighty-four Pannon White kits of 73 newborn litters were submitted to one of five treatments. Control litters (SS) were nursed once a day for 35 days post partum (traditional method of nursing). DD litters were raised by two does and the kits were nursed both in the morning and in the evening until day 35 post partum. DS litters were nursed twice a day for 23 days, and then once a day until weaning at 35 days. Part of the DS litters were nursed at 08:00 and 20:00 h (i.e. every 12 h, DS12), the rest were nursed at 08:00 and at 16:00 h (DS8). Kits of the fifth treatment (D0) were nursed twice a day until day 23, and then immediately weaned.

Rabbit kits that were nursed twice a day (DD, DS12, DS8, D0) consumed on average 1·89 more milk compared with SS individuals until day 23 (overall treatment effect P < 0·001). The 21-day body weight of these young was 1·7 times greater than that of the SS kits (overall P < 0·001). D0 rabbits were weaned early and their growth curve showed a slight break at this point. However, they compensated for this lag by the end of the fattening period. SS rabbits and DD ones were respectively the first and the last to start consuming solid food. The food consumption of DS rabbits was similar to that of DD until day 23 and from then until day 35 it was not significantly different from that of SS. After having been weaned on day 23, D0 kits consumed only very small quantities of pellets for 2 days. Afterwards their food intake increased abruptly. Rabbits that were nursed twice a day (DD, DS12, DS8 and D0) consumed more food as compared with the SS individuals throughout the total period of fattening (157 v. 137 g/day; P < 0·05). The weight at 10 weeks of age was 2·49 v. 2·88 kg (overall P < 0·001), respectively for SS and doublenursed (DD, DS, D0) rabbits. Nursing twice a day did not affect dressing proportion but the proportion of the carcass in the front part of the body decreased slightly (318 v. 323 g/kg; P < 0·05) while that in intermediate part increased (321 v. 307 g/kg; P < 0·05). Nevertheless, rabbits that were nursed twice a day had more (P < 0·05) perirenal + scapular fat and produced heavier livers. Total fat content of the empty body, however, was not significantly higher, with the one exception of the DD rabbits which had higher levels than any other group. The results of our experiment show clearly that the growth potential of rabbit kits is strongly limited by the milk availability during the first weeks post partum.

In a study of the growth of various body parts of the ostrich, only the growth of the head could be described with the Gompertz function. The growth of the ostrich head (y in g) with time (x in months) is described by the Gompertz function y = 613 exp[−ln (613/133) exp(−0·26x)]. This information could be used in the design of carcass classification systems.

1. Two series of energy balance trials were conducted with British Friesian veal calves. In the first, calves were given a milk replacer diet at three different planes of nutrition. In the second, calves were raised from about 80 to 180 kg at four air temperatures, 5°, 10°, 15° and 20°.

2. The net efficiency of utilization of the milk replacer diet for growth was 0·72. The effect of body size on heat production in growing calves was best expressed by an exponent of body weight slightly but not significantly below W0·75.

3. Measurements of heat production estimated from respiratory exchange and heat loss measured by direct calorimetry agreed exactly at all planes of nutrition. Heat production at zero energy retention was 675 kJ/kg W0·75 per 24 hr.

4. Average daily live-weight gain and total heat loss were the same at all air temperatures. Changes during growth in the partition of heat loss into its sensible and evaporative components indicated that calves acclimated progressively to the air temperatures to which they were exposed.

The effectiveness of silastic rubber implants impregnated with melengestrol acetate (MGA) to suppress heat in heifers being finished for beef was tested. Nine uniparous females received MGA implants, nine received 0·5 mg MGA orally and eight similar non-treated animals served as controls for a 110-day experimental period. Based on occurrence ofheat and ovarian examination during treatment and at slaughter, the silastic implants were effective in suppressing heat throughout the experimental period. The animals with implants also had a significantly higher rate of daily gain than the controls (P<0·1). In a second experiment the implants were effective in suppressing heat but the increase in daily gain did not reach significance. Silastic implants of MGA are effective for the long-term suppression of oestrus in finishing heifers and their effective life span is sufficiently long for use under commercial farming conditions.

Records on 695 lambs were collected over a period of 5 years from 1961/62 to 1965/66, at Ras El-Hekma Desert Research Station, 230 km west of Alexandria. The characters studied were birth, weaning and yearling body weights, pre- and post-weaning daily gains and greasy fleece weight.

Birth, 120-day and 365-day body weights were 3·4, 18·2 and 33·4 kg respectively. Greasy fleece weight at 16 months of age was 3·29 kg. Heritability estimates of birth, weaning, yearling weights, pre- and post-weaning daily gains and greasy fleece weight were 0·22, 0·45, 0·41,0·45 and 0·29 respectively. Genetic and phenotypic correlations between birth, weaning and yearling weights were all positive and significant. Genetic correlations between fleece weight and body characteristics were negative and low.

Two experiments are described to investigate the effect of different weights of pigs at 56 days of age on live-weight gain, efficiency of feed utilisation and bacon carcass quality.

1. In Experiment I a comparison was made between 32 pairs of weaners, reared on the sow, which weighed 31·0 1b. and 45·4 1b. respectively at 56 days of age. After separation into heavy and light groups the pigs were group fed to bacon weight.

The heavy weaners reached 200 1b. eighteen days earlier than the light weaners but this difference was due completely to the slower rate of growth to 50 1b. live-weight. The heavy weaners required 3·59 1b. of meal per 1b. live-weight gain from 56 days of age to bacon weight compared with 3·50 1b. for the light weaners but there was no difference in efficiency of feed utilisation during the period taken to grow from 50 to 200 1b. There were no significant differences between the carcasses apart from an increased flare weight in the light weaners.

2. In the second experiment both suckled and early-weaned pigs were reared to 30, 40 and 50 1b. at 56 days of age and then fed individually to 200 1b.

The number of days taken to reach 200 1b. was 168·6 for the 50 1b. pigs, 176·6 for the 40 1b. pigs and 182·1 for the 30 1b. pigs; there were no differences due to the methods of rearing. The efficiency of feed utilisation from 56 days to 200 1b. was not affected by method of rearing but as weight increased from 30 to 50 1b. at 56 days, the meal required for a pound of subsequent live-weight gain increased from 3·06 to 3·24 1b.

The number of days to increase from 50 to 200 1b. live-weight was 110·4 for the 50 1b. pigs, 109·3 for the 40 1b. and 106·3 for the 30 1b. pigs, again there being no differences due to the methods of rearing. There were no differences in efficiency of feed utilisation from 50 to 200 1b.

Neither weight at 56 days nor method of rearing markedly affected the quality of the carcass but there was an indication that 56-day weight caused greater differences in the early-weaned treatments than in the suckled treatments.