The main objective of the present work was to determine the nutritional value and the strategies of using green banana meal (BM) in growing pigs. Two trials involving a total of 96 growing pigs were designed to study the effect of the harvest stage on the nutritional and energy values of BM (trial 1) and to evaluate the consequence of feeding gradual levels of BM on growth performance and feeding behavior in growing pigs (trial 2). In trial 1, the digestive utilization of three diets including 40% BM were compared with a control (C) soybean meal-corn diet in two batches of 12 pigs. BM was obtained from fruits harvested at 750 degrees-days (DD; early harvesting stage), 900 DD (normal harvesting stage) and 1150 DD (late harvesting stage). In trial 2, 72 Large White pigs were grouped in pens of nine animals and were given ad libitum access to one of the four dietary treatments (two pens/diet) differing from the rate of inclusion of 900 DD BM (0%, 20%, 40%, 60%). The estimated energy apparent digestibility coefficients of BM increased with the harvest stage (75.5%, 80.7% and 83.2% for BM at 750, 900 and 1150 DD, respectively). Digestible energy and metabolizable energy values were higher for BM at 1150 DD (13.56 and 13.05 MJ/kg DM, respectively) than at 900 DD (13.11 and 12.75 MJ/kg DM, respectively) or at 750 DD (12.00 and 11.75 MJ/kg DM, respectively). In trial 2, average daily gain and feed conversion ratio were not affected (P>0.05) by the rate of BM inclusion (822 g/day and 2.75 kg/kg on average, respectively). Feed intake and feeding behavior parameters were not significantly influenced by the dietary treatments except for the rate of feed ingestion with a lower value for the diet with 40% of BM (27.4 v. 32.2 g/min on average; P<0.01) when compared with the other diets. Results of this study indicate that the energy value of BM increases with the harvest stage and that BM can be incorporated up to 60% in growing finishing pig diets.

A comparison was undertaken of 92 Canadian Holstein × British Friesian (HF) and 93 British Friesian (F), autumn born, male calves on three typical United Kingdom production systems. These were: intensive barley beef system (BB); a grass/cereal 18-month system (18m); and 24-month forage system (24m). Calves were brought in from a variety of farms. HF calves were heavier on arrival (43·1 v. 40.7 kg ***). The calves were the progeny of 27 Canadian Holstein and 43 British Friesian sires, and all out of British Friesian dams. They were castrated and reared conventionally to 100 kg before being allocated to treatment. Slaughter was undertaken when subjective handling suggested that the carcass would classify as fat-class 2 on the Meat and Livestock Commission classification scheme (equivalent to European Economic Community fat-class 3), provided that a minimum live weight (BB, 380 kg; 18m/24m, 420 kg) was achieved. There were no differences between breeds in daily live-weight gain on any system. Other results, HF first, follow. At slaughter, HF were both older (BB, 362 v. 342 days **; 18m, 591 v. 558 days ***; 24m, 716 v. 673 days ***) and heavier (BB, 413 v. 395 kg ***; 18m, 486 v. 469 kg NS; 24m, 531 v. 496 kg ***). Efficiency of food conversion, measured on the BB system only, was not significantly different (5·83 v. 5·84).

Eighteen mature (3 to 6 years) Debouillet × Rambouillet ewes (mean weight 79·2 (s.e. 21) kg) producing and nursing single offspring were randomly allotted to one of three groups to examine the influence of ovine growth hormone (oGH) on reproductive, hormonal and lactational responses of springlambing ewes. Each ewe received a daily subcutaneous injection of either 0, 5 or 10 mg oGH from day 11 through to day 20 post partum (day 0 = parturition). Treatment groups were subdivided into two pens (three ewes per pen) and food intake was monitored from day 1 through to day 20 post partum. On days 11 and 20 post partum, jugular blood samples were collected before and hourly for 8 h after treatment. Blood samples were also collected daily from day 10 through to day 21 post partum and on alternate days through to day 40 post partum. Milk production (oxytocin-induced hand milking) and fat and protein concentrations were determined 21 days post partum. Food intake did not differ before or during the treatment period (P > 0·05). Likewise, ewe and lamb weights were similar among treatment groups through to day 60 post partum (P > 0·05). Serum insulin did not differ before or after treatment on day 11 (P > 0·05); however, on day 20 before treatment, serum insulin was significantly higher in ewes receiving 5 (2·3 (s.e. 0·3) μg/I) and 10 (2·4 (s.e. 0·3) μg/1) mg oGH than in controls (1·2 (s.e. 0·3) μg/1) (P < 0·05). After treatment, no differences were detected in serum insulin among treatments on day 20 post partum (P > 0·05). Serum growth hormone (GH) was similar among groups before treatment on day 11 post partum; but by 8 h after treatment, serum GH was significantly elevated in ewes receiving 10 mg oGH (32·4 (s.e. 1·9) μg/1) compared with ewes receiving 5 (13·9 (s.e. 1·9) μg/1) or 0 (4·5 (s.e. 1·9) μg/1) mg oGH (P < 0·01). By 20 days after lambing, serum GH differed significantly among groups both before and after administration of exogenous oGH (P < 0·01). Ewes receiving 5 or 10 mg oGH produced 2·3 (s.e. 0·2) kg milk per day compared with 1·9 (s.e. 0·2) kg/day for controls (P < 0·10). Milk fat and protein concentrations did not differ significantly among treatments (P > 0·05), but total fat yield was higher in ewes receiving either dose of oGH (206 (s.e. 20) g/day) compared with control ewes (141 (s.e. 20) g/day) (P < 005). Serum progesterone remained less than 0·5 μg/1 in ewes through to day 40 post partum. A linear decrease was observed in interval from parturition to first observed oestrus as dosage of oGH increased (116, 108 and 102 (s.e. 6) days for ewes receiving 0, 5 and 10 mg oGH, respectively; P = 0·10). Administration of exogenous oGH to lactating. anoestrous ewes between days 11 and 20 post partum enhances milk production and may influence the interval to oestrus.

Two experiments were conducted in consecutive years in which recently (Experiment 1) or temporarily (Experiment 2) weaned ewes and matched post-partum non-lactating flockmates (DRY) were exposed to a stimulus group of rams and oestrous ewes (10 and 20 in Experiment 1, 20 and 20 in Experiment 2) for 28 days in spring. Lactating ewes (n = 130) in Experiment 1 were isolated from their lambs 4 (W-4), 2 (W-2), 1 (W-1) or 0 (W-0) days in advance and exposed along with a group of 32 DRY flockmates. Lactating ewes in Experiment 2 (n = 230) were allocated to an unreplicated factorial of two levels of temporary weaning before stimulation (B0: control; B24: lambs removed 24 h before stimulation) by four levels of ewe-lamb contact imposed at the start of the stimulation (A0: control; A12, A24 and A36: lamb-ewe separation during the initial 12, 24 or 36 h of exposure); DRY ewes (n = 54) acted as an augmented factorial control. Oestrus (rump marks) and ovulation (laparoscopy on day 5 and on day 28 (Experiment 1) or day 32 (Experiment 2)) were recorded. Ovulation and oestrous responses in Experiment 1 were similar for DRY (90.6% and 55.2%, respectively) and recently weaned ewes (83.8% and 53.7%, respectively). Amongst recently weaned ewes, the immediate ovulation response to the rams and the proportion of ewes still cycling by day 28 tended to be lower (P = 0.065 and P = 0.011) in ewes weaned on the day of ram exposure (71.9% and 54.8% v. 87.8% and 80.0%, respectively). Ovulation rate was lower (P < 0.003) in W-2 ewes (1.3 ± 0.10) than in the other recently weaned groups. In Experiment 2, ovulation (83.3%) and oestrous (68.9%) responses in DRY ewes were higher (P = 0.022 and P = 0.053, respectively) than in lactating ewes (66.2% and 51.0%, respectively). More ewes ovulated (P = 0.036) in B24 (70.5%) than in B0 (61.8%). Ewes having their lambs returned 12 h after the onset of stimulation (A12) had poorer ovulation responses (54.9%) than control ewes (A0, 72.9%, P < 0.05); this was probably associated to lamb restitution after the sunset. Main conclusions were that (i) the presence of the lambs is a depressing factor of both ovulation and oestrous responses to the ram effect in lactating ewes, (ii) the ovulation response of lactating ewes will probably benefit from removing lambs for a period of 24 h before the onset of stimulation, (iii) until additional information becomes available, temporary weaning protocols should be designed avoiding lamb restitution during the night.

Although only a few specific pigmentation types are allowed within the Hucul horse registry, accurate determination of particular coat colors can be uncertain due to the presence of variation in color shades and segregation of multiple dun dilution variants. Herein, we genotyped the previously identified polymorphisms within two coat color loci TBX3 (T-box 3) and ASIP (Agouti Signaling Protein) in 462 Hucul individuals and compared the genotype predicted phenotypes with observed pigmentation types provided in the Polish Horse Breeders Association database. We identified disagreement between the predicted and recorded coat color in 157 horses (34%). The most common error was misclassification of horses with the nd1/nd1 and nd1/nd2 genotypes, what may be related with the occurrence of some ‘intermediate’ dilution phenotypes in such individuals. We have also proven that the frequency of the dominant dun dilution allele (D) (0.30) is higher than previously predicted by available studbooks. The D allele(s) is easily ‘hidden’ in various phenotypic groups including dark bay and black, therefore we hypothesized that the dun dilution effect itself is not as strongly epistatic in the Hucul horse as described in other horse breeds. This may be the result of an additional genetic modifier suppressing D allele phenotypic effect.

Three goats provided with oesophageal and ruminal cannulae were used to determine variations in dry matter (DM) and neutral-detergent fibre (NDF) degradability of the forage consumed when grazing thorn scrubland in the semi-arid region of north Mexico, during two consecutive dry and wet periods. Ingesta samples were incubated intraruminally, the data were fitted to the exponential equation P = a + b (l - e-ct) and statistically analysed using a randomized-block design. Organic matter and crude protein (CP) contents were higher (P < 0.05) in the wet seasons. Values of NDF were similar in dry and wet season of both years whereas higher numerical values of acid-detergent fibre (ADF), lignin and cellulose were registered in the dry seasons. DM and NDF degradabilities after 24 and 48 h of ruminal incubation were higher (P < 0.05) in the wet seasons. Higher values (P < 0.05) in DM and NDF bag losses at zero time (A fraction) were registered in the two wet seasons. The insoluble but fermentable DM and NDF (B fractions) were higher (P < 0.05) in the 1999 wet season and variable in the rest of the studied period. Numerically higher values of DM and NDF c fraction were found in wet periods, whereas DM and NDF potential degradabilities were higher (P < 0.05) in the wet season in 1999 and similar across seasons in 2000. Lowest (P < 0.05) contents of CP in grazed forage, DM and NDF degradabilities after 48 h of ruminal incubation, and A, and B, and c fractions were observed in the dry seasons. Thus, these results may be related to both the lower feeding value of forage consumed by the animals and lower performance of livestock during this period. Then, the DM and NDF degradability after 48 h, together with the insoluble but fermentable matter and the c fraction permit the nutritive value of the forage consumed by grazing goats to be accurately described.

Measurements were made of apparent digestibility of dry matter, nitrogen and lipid, nitrogen balance, pancreatic lipase activity and carcass composition in eight non-pregnant sows during three 10-day balance trials during which the feed intake was 1·1, 0·8 and 2·6 kg/day of a diet containing 14·69% crude protein and 3·0 Meal gross energy/kg DM.

All the sows had similar breeding histories and had completed their fourth lactation. Four were in standard condition (mean body weight, 160 kg) and four in thin condition (mean body weight, 134 kg). All the animals lost weight and were in negative nitrogen balance while on the two lower levels of feed intake; the thin sows lost significantly more N than the standard animals (P < 0·05) and on the lowest level of feeding digestibility of DM by the thin sows was significantly less (P < 0·001).

In both groups there was a rapid recovery in nitrogen retention and in body weight when the food intake was increased.

An experiment was conducted to examine the effects of dietary fibre and starch levels on the response to condition score at calving. Fifty-two cows were used over two winter feeding periods, with 24 and 28 different cows in each. Twelve weeks before their expected calving date, cows were paired and the level of feeding adjusted to attain mean condition scores at calving of 2·0 (T) and 3·5 (F) within pairs. At calving, pairs of cows were allocated to treatment HF or LF, giving four groups in total. Each day for the first 16 weeks of lactation, all cows were offered 10 kg dairy concentrate containing either high-fibre/low-starch (FHF and THF), or low-fibre/high-starch (FLF and TLF), 2 kg sugar-beet pulp and hay ad libitum. Two cows from each group were used to determine apparent digestibility of the whole diet each year, using chromium III oxide as a faecal marker. Eight steers were used to determine the degradabilities of dry matter, nitrogen and fibre in the two concentrates and to provide rumen fluid samples for volatile fatty acid determination.

The Israeli procedure for measuring sire breeding values and genetic progress due to selection is described. The estimate of sire breeding value has two components, the current contemporary comparison (CC) and an adjustment for the average genetic deviation of the contemporaries from the original base population. The combined value is called the cumulative difference (CD). For practical purposes the CD was found to be free of the time trends observed for CC, and the residual variances of the two measures were approximately equal. The relative genetic level in any given time interval was measured by the average CD of all sires used during the period October 1964 o t January 1971 in Israel. The analysis indicates that essentially all of the progress in 122-day FCM yields was due to sire selection, whereas 60% of the progress in 305-day FCM yields was due to selection and 40% to improved management.

Blood samples were taken from Scottish Blackface ewes of five lines (selected for long and short cannon bones, for hairy and fine fleeces, and an unselected control line) at ages ranging from 9 to 69 months. The samples were analysed for the concentrations of copper, glucose, calcium, magnesium, phosphorus, total protein, albumin and globulin in plasma.

The components of variance and covariance between sires and within sires were estimated and heritabilities were calculated for the eight blood constituents and live weight. The heritabilities ranged from 0·20 (s.e. 0·08) for the concentration of copper to 0·43 (s.e. 0·10) for total protein. Only one of the 34 genetic correlations was significantly different from zero, this being between the concentrations of calcium and phosphorus.

Ewes that had had a single lamb 9 months earlier had lower concentrations of copper, calcium, albumin (P < 0·001) and glucose (P < 0·01) than ewes that had not lambed. Concentrations of glucose (P < 0·05) and total protein (P < 0·001) were also decreased according to the number of lambs born to the ewe 3 months later.

Ewes with low red cell potassium concentrations had higher concentration of glucose in plasma than ewes with high red cell potassium concentrations (P < 0·05). Haemoglobin type affected the concentrations of copper (P < 0·01) and total protein (P < 0·05), with ewes of type B having higher and lower concentrations respectively. The constituents measured were not significantly affected by transferrin type.

Wastewater discharge and agricultural activities may pose microbial risks to natural water sources. The impact of different sources can be assessed by water quality modelling. The aim of this study was to use hydrological and hydrodynamic models to illustrate the risk of exposing grazing animals to faecal pollutants in natural water sources, using three zoonotic faecal pathogens as model microbes and fictitious pastures in Sweden as examples. Microbial contamination by manure from fertilisation and grazing was modelled by use of a hydrological model (HYPE) and a hydrodynamic model (MIKE 3 FM), and microbial contamination from human wastewater was modelled by application of both models in a backwards process. The faecal pathogens Salmonella spp., verotoxin-producing Escherichia coli O157:H7 (VTEC) and Cryptosporidium parvum were chosen as model organisms. The pathogen loads on arable land and pastures were estimated based on pathogen concentration in cattle faeces, herd prevalence and within-herd prevalence. Contamination from human wastewater discharge was simulated by estimating the number of pathogens required from a fictitious wastewater discharge to reach a concentration high enough to cause infection in cattle using the points on the fictitious pastures as their primary source of drinking water. In the scenarios for pathogens from animal sources, none of the simulated concentrations of salmonella exceeded the concentrations needed to infect adult cattle. For VTEC, most of the simulated concentrations exceeded the concentration needed to infect calves. For C. parvum, all the simulated concentrations exceeded the concentration needed to infect calves. The pathogen loads needed at the release points for human wastewater to achieve infectious doses for cattle were mostly above the potential loads of salmonella and VTEC estimated to be present in a 24-h overflow from a medium-size Swedish wastewater treatment plant, while the required pathogen loads of C. parvum at the release points were below the potential loads of C. parvum in a 24-h wastewater overflow. Most estimates in this study assume a worst-case scenario. Controlling zoonotic infections at herd level prevents environmental contamination and subsequent human exposure. The potential for infection of grazing animals with faecal pathogens has implications for keeping animals on pastures with access to natural water sources. As the infectious dose for most pathogens is more easily reached for calves than for adult animals, and young calves are also the main shedders of C. parvum, keeping young calves on pastures adjacent to natural water sources is best avoided.

The mean concentrations of total serum protein, γ-globulin and antibody were almost identical in groups of Finnish Landrace lambs from litters in which one, two or three, respectively, survived till the 3rd day. Lambs from two litters each with four survivors had considerably lower mean concentrations. Merino × Cheviot and Scottish Blackface lambs examined previously had significantly lower serum protein concentrations than the Finnish lambs and higher antibody levels in single than in twin lambs.

Transfer to slaughter may be very stressful for cattle and negatively affect their ultimate carcass pH. A potential link between farmers’ attitudes, farmers’ behaviour, responses of animals to handling and carcass pH in beef bull production was questioned. Whether carcass pH depends on experiences in handling and social mixing was analysed. We conducted a survey on commercial farms where we questioned farmers on their work and beliefs about bulls. Farmers’ behaviour with bulls during a test and bulls’ behaviour during loading in the truck for transport to the slaughterhouse were observed. The ultimate carcass pH was measured. Farmers tended to behave more gently with their bulls when they had positive attitudes towards gentle contacts with bulls (P = 0.07). The loading of bulls in the truck tended to be more difficult when the farmer was more ready to approach his bulls (P = 0.07). Carcass pH was higher for bulls that had not been transferred from a breeding to a finishing unit (P = 0.03). It tended to be higher when the farmer did not display a gentle behaviour (P = 0.09). The link between farmers’ attitudes and farmers’ behaviour and the lower meat pH resulting from a gentle farmers’ behaviour during finishing are consistent with previous findings in pig, veal or dairy productions. However, the present links were weaker than in the other productions, probably due to the low frequency of close contacts between farmers and beef bulls. When loading bulls into a truck, handlers use the tendency of animals to avoid people, hence overly positive behaviour with the animals during finishing may result in more difficulties at loading. In that case, use of alternative driving aids should be recommended. Our results on carcass pH suggest some habituation to transport among bulls transferred between breeding and finishing, even though the two experiences are several months apart. In view of our results, it seems that contacts with bulls, when they are needed, should be gentle.

In a previous experiment with pregnant beef cows (Alawa, Fishwick, Parkins, Hemingway and Aitchison, 1986) when equal amounts of crude protein (CP) were supplied from a range of concentrates providing different amounts of rumen-degraded protein (RDP), the voluntary intake of barley straw dry matter (DM) and the metabolizable energy (ME) obtained from straw were positively and significantly correlated with the intake of RDP. Whilst increasing proportions of rumen-undegraded protein (UDP) have been shown to increase the milk yield of ewes (Robinson, McHattie, Calderon Cortes and Thompson, 1979) the response of lactating beef suckler cows to UDP in terms of milk yield is not clear. There is an increasing interest in the use of peas as a protein supplement but they have not been compared with more conventional protein sources. Accordingly these present experiments were conducted to study the response of lactating beef cows and their calves to proteins from different sources providing different amounts of RDP and UDP.

The pacific white shrimp, Litopenaeus vannamei, is a popular species in aquaculture. Abdominal muscle accounts for 90% of shrimp flesh. Its growth and related genes, particularly the regulatory genes, is not well known. A cDNA library of shrimp juvenile abdominal muscle was established by PCR-based SMART™ cDNA technology. Library size was 5.0 × 106 pfu (plaque-forming unit) independent clones per microgram of starting RNA with the percentage of recombinant clones >95%. Sequence analysis of 311 randomly picked positive clones revealed 197 expressed sequence tags with average insert size of 745 nucleotides, 56% (110 of 197) clones having 5′-end sequence and 44% (87 of 197) clones having 3′-end sequence. Queries of the sequences by Blast identified 37 unknown sequences, and 160 unique clones, including 67 sequences of 100% identity matches, 28 high homologies (80% to 90% sequence match, >100 bits hit score in Blastn), 65 medium homologies (>100 bits hit score in Blastp) to the known EST sequences in the database. Among the high identity-matched ESTs, 12S ribosomal RNA, actin 1, actin 2, arginine kinase and beta-actin were the most abundant transcripts with 5 to 20 times of hit. Primary hit sequences originate from shrimp, insects, lobsters, crabs and crayfish. The EST sequences were categorized as muscle structural proteins (25%), rRNA and protein synthesis (25%), followed by mitochondrial functions (22%), exoskeleton (14%), enzymes (6%) and RNA splicing (2%), suggesting abundant and diverse transcripts present in the shrimp abdominal muscle cDNA library.

A divergent selection experiment on litter size variability (high and low lines) was performed in rabbits over seven generations. The aim of this study was to evaluate the correlated responses to selection in body condition and fat reserves mobilisation. Litter size variability was estimated as phenotypic variance of litter size within female after correcting for the year-season and the parity-lactation status effects. A total of 226 females were used in this study, of which 158 females were used to measure body condition and energy mobilisation. Body condition was measured as BW and perirenal fat thickness. Females were stimulated with the adrenergic isoproterenol. Mobilisation capacity of fat reserves was measured by the lipolytic potential, defined as the increment in non-esterified fatty acids (NEFA) levels from basal concentration until adrenergic stimulation at mating, delivery and 10 days after delivery of the second reproductive cycle. Females were classified as survivor or non-survivor when they were culled for sanitary reasons or died before the third kindling. Data were analysed using Bayesian methodology. Survivor females presented higher BW than the non-survivor females at delivery (238 g, P=1.00) and 10 days after delivery (276 g, P=1.00). They also showed higher perirenal fat thickness at 10 days after delivery (0.62 mm, P=1.00). At delivery, basal NEFA levels was lower in survivor than non-survivor females (−0.18 mmol/l, P=1.00), but their lipolytic potential (∆NEFA) was higher (0.08 mmol/l, P=0.94). Body weight was similar between lines in survivor females. Perirenal fat thickness was lower in the high line than in the low line at delivery (−0.23 mm, P=0.90) and 10 days after delivery (−0.28 mm, P=0.92). The high line exhibited higher NEFA (0.10 mmol/l, P=0.93) and lower ∆NEFA (−0.08 mmol/l, P=0.92) than the low line at delivery. The low line showed a favourable correlated response to selection on body condition and fat reserves mobilisation. In conclusion, the low line selected for litter size variability seems to adapt better to adverse conditions, as it has a greater capacity to mobilise energy reserves at delivery than the high line. Females that adequately manage their body reserves and perform energy mobilisation correctly have a lower risk of dying or being culled.

In the breeding of dairy cattle the selection of bulls to breed young bulls for progeny testing is a crucial process. This paper compares several policies for making this selection based on the criteria-selection response, inbreeding depression, loss of genetic variance and variability of response. A number called the ‘effective number of new bulls to breed bulls selected each year’ (NBBe) is defined which is closely related to the last three of these criteria. Past studies of the design of dairy cattle breeding programmes have assumed that selection is within a group of bulls progeny tested in the same year (policy I). However, modern sire evaluation methods allow comparison of sires tested in different years. To evaluate the effect of selecting bulls to breed bulls from all available bulls (policy II) a computer simulation program was used. Policy II results in an increase in the response to selection but a substantial decrease in NBBe. When compared at the same NBBe, policy II results in a smaller selection response than policy I. A policy which allows the best bulls to be used for more than 1 year but which limits the maximum number of years for which they can be used, results in the best compromise. If bulls are to be used for several years there is little advantage to be gained from making more matings within each year to more high-rated bulls or to older, more reliably evaluated bulls.

The influence of naturally acquired nematode infections on food intake and utilization was investigated in grazing lambs. It was first demonstrated in a pilot study with penned lambs that the application of chrome-oxide in a ruminal bolus could be used for comparison of food intake in infected and uninfected lambs on grass. In a field trial, repeated in two consecutive seasons, 48 lambs grazed on clover grass in six groups. Three stocking rate groups were grazed on contaminated pastures (I-low, I-medium and I-high) and three groups on clean pastures (U-low, U-medium and U-high). Faecal dry-matter (DM) output of individual lambs was estimated in August each year by the chrome-method. DM intake and food conversion efficiency were calculated based on hand-picked herbage samples and in vitro assessment of digestibility. Substantial worm burdens, increasing from year 1 to year 2, were observed and some lambs had clinical symptoms in the 2nd year. In year 2, lambs on contaminated pastures had significantly lower DM intake (proportionately 009 lower), higher faecal protein losses and lower food conversion efficiency compared with the uninfected lambs on clean pastures. The effect of infection on food intakes was eliminated if corrected for body weight. The study showed that if exposure to nematode infections is large enough, increased protein losses in faeces and anorexia may contribute to reduced performance in lambs in late season.

Four groups of eight primiparous ewes and their single lambs were grazed for 2 weeks on pasture containing one of four novel grass species – perennial ryegrass, timothy, cocksfoot and red fescue. When subsequently grazed in a field with randomized plots of the four species, both ewes and lambs spent longer grazing the species to which they had been accustomed than was spent by ewes and lambs accustomed to other species. This effect was proportionately greater for the lambs than the ewes, and the lambs responded most to experience of cocksfoot and red fescue. Both ewes and lambs spent most time grazing perennial ryegrass and timothy, and least time grazing red fescue, with cocksfoot intermediate. It is concluded that perennial ryegrass and timothy are grazed by ewes and lambs in preference to cocksfoot and red fescue, but that a two week period of experience will increase the attractiveness of the less-preferred species, particularly to lambs.

The research has shown the interesting contributions of shearing in mid-gestation on the performance of lambs from birth to weaning. Other studies have reported that shearing at early pregnancy influences the development of the placenta and lamb live weight at birth. However, there was a lack of information on the effect of early-prepartum shearing on the behavior of the offspring from weaning onward. This study evaluated the effect of shearing ewes at 50 days of gestation on the growth, reproductive behavior and response to a gastrointestinal parasite challenge in the female offspring from weaning to 18 months old. Fifty-seven Polwarth female lambs were used, 22 being singles and 35 twins born to ewes either shorn at 50 days of pregnancy (PS, n = 23) or shorn at 62 days postpartum (U, control, n = 34) resulting in four subgroups: single lambs born to PS ewes (n = 8), born to U ewes (n = 14), twin lambs born to PS ewes (n = 15) or born to U ewes (n = 20). All progeny were managed together under improved pasture with a minimum forage allowance of 6% live weight on dry basis. Body weight, body condition score and fecal eggs count were recorded every 14 days from weaning to 18 months of age. Concentrations of progesterone were measured weekly (from 4 to 10 months of age and from 14 to 18 months of age) to establish the onset of puberty. Ovulation rate at an induced and a natural heat (545 ± 1.0 and 562 ± 1.0 day old) was recorded. Prepartum shearing did not affect the age at puberty or the ovulation rate of female offspring, but those born as singles were more precocious ( P = 0.03) and heavier ( P = 0.02) at puberty than twin born lambs. Both the average value of parasite egg count ( P = 0.0 7) and the Famacha index ( P = 0.02) for the entire study period were lower in lambs born to prepartum shorn ewes than those born to postpartum shorn ewes. In conclusion, shearing at 50 days of gestation did not affect the growth or the reproductive behavior of female offspring. However, female lambs born from ewe shorn during gestation showed a better response to the parasitic challenge, and further research is required to confirm this.