Straw-Flow is a novel housing system for growing pigs which simplifies the handling of bedding and manure by allowing pigs to take unchopped straw from dispensers. Three groups of 50, 50 and 60 Large-White × Landrace pigs were housed in Straw-Flow pens from 5 to 90 kg. They were supplied daily with 50 to 100 g unchopped straw per pig and given food ad libitum. From 30 to 90 kg, mean growth rate was 863 g/day and food conversion ratio was 2·56 kg food per kg growth. The pigs' behaviour was divided approximately into: 0·820 lying, 0·100 active, 0·075 feeding and 0·005 drinking (on a proportional basis). There were no differences (P > 0·05) between groups or different weights for any of the behaviour categories. The pigs were less active before noon than after noon (P < 0·05). The daily number of visits to the drinker between weights 5 and 25 kg fell from 23·7 to 11·0 (P < 0·05). A single drinker, of new design, appeared to be adequate for a group of 50 to 60 pigs.

Piglet body composition at weaning could be a determinant for pig’s viability and may be influenced by factors such as the nutritional management followed during suckling. An experiment was conducted to study whether intermittent suckling (IS) affects body composition at weaning and nutrient and energy retention during a 34-day lactation period in Iberian piglets. Litters were subjected to conventional suckling (CS) or IS (n=10 litters of six piglets per treatment) in two trials. All piglets had ad libitum access to creep feed from day 15 onwards. In IS, piglets were progressively separated from the sow for 6, 8 and 10 h daily during the last week of lactation, whereas in CS piglets had continuous access to their dams. Creep feed intake in litters and BW development of individual piglets were measured throughout the 34-day lactation. Within each litter, both at birth and at weaning (day 35), one piglet was used to assess nutrient retention and body composition by the comparative slaughter approach. During days 29 to 35 of the experiment, daily creep feed intake was greater in IS piglets (IS 124, CS 67 g/piglet, P=0.040), and average daily gain differed significantly between groups (IS 190, CS 150 g/day, P=0.010). BW at weaning was higher in the IS than in the CS piglets (IS 8.19, CS 7.48 kg, P=0.011). Empty-body fat and energy content at weaning were higher in the IS compared with CS litters, as well as fat content in the carcass (P=0.04). The IS treatment did not affect empty-body protein deposition, but significantly increased daily retention of fat, energy, ash and calcium, compared with CS litters (P<0.05). Thus, IS in Iberian piglets seems to enhance feed intake, growth rate and retention of some body components, which may contribute to a higher body fat content at weaning and facilitate the weaning process.

A major problem facing breeders interested in using bulls from other populations is that the foreign bull evaluations cannot be directly compared with the evaluations produced in the United Kingdom (UK). This is due to differences in the units of measurement, the base against which all bulls are compared and the method used to express the merit of the bulls. In order that selection is possible on an equal basis, it is necessary to be able to convert bull evaluations from the scale used in the country of export to that used in the importing country.

The general formula used to convert evaluations is of the form Y = a + bX where Y is the converted evaluation, X is the evaluation in the exporting country, a is the difference between the bases used for bull evaluations and b is the factor to take account of the differences in scale.

Among the most important of the parasites of grazing animals are the nematodes inhabiting the alimentary tract of the sheep. The losses due to the presence of these worms are difficult to estimate but are certainly not confined to the results of disease outbreaks. In fact, recent research (Tayler, 1953; Spedding, 1953) has emphasised the losses which occur at sub-clinical levels of infestation, that is, at levels sustained by normal sheep.

Control of these parasites may be either ameliorative or preventive in character. Supplementary feeding and the use of anthelmintic drugs are of the former type; grazing management is essentially preventive. For the most part, anthelmintic drugs are now capable of preventing the outbreak of clinical disease, but they allow the presence of sub-clinical levels of infestation, as do most types of grazing management.

The silver fox is an extreme seasonal breeder with one reproductive season during the year. Males are sexually mature at the age of 9 to 10 months. In the present study reproductive function in yearling and adult silver fox males before and during the reproductive period was examined. The aim was to determine the age-dependent features of their reproductive system. It was found that yearling males mate with a smaller number of females and that their first mating period is shorter compared with adult foxes. A high proportion of yearling males did not mate at all (27%) or their sexual activity was reduced (26%), although the number of pups horn from mating males was normal. During the peak of male sexual activity, the number of spermatozoa in the ejaculate was lower in yearling compared with adult males. However, there was no difference in the number of abnormal forms of spermatozoa between the two groups. There was no significant difference in sperm numbers between sexually active and inactive yearlings. Before the reproductive season, yearling males did not differ from adults in plasma concentration of testosterone, while body and testes weights and level of oestradiol were lower. At the end of the breeding season, yearlings did not differ from adults in any trait. It is concluded that the reproductive capacity of yearling male foxes might he immature before the first breeding seasons but that this immaturity did not decrease their reproductive success.

Whole, dry barley treated with ammonia (A), whole, untreated barley (WU) or ground barley (G) were fed with hay and a little high protein concentrate to 7 to 11-month-old lambs. Most apparent digestibility coefficients were found to be 3 to 5 units higher in the diet with barley A than in diets with barley WU or G, the differences being significant. Calculation of the digestibility of barley by difference showed that the coefficients were 8 to 10 units higher in barley A than in barley WU or G as regards dry matter and organic matter. Digestion of crude fibre was better in both A and WU than in G. These differences were also significant.

Water balance, electrolyte and acid-base status of a group of five South African Mutton Merino wethers given chopped lucerne hay ad libitum was determined before and after ileorectal anastomosis. In general, the sheep recovered rapidly from surgery, resuming, within 10 days, a level of dry matter intake only slightly less than pre-operative levels (1323 (s.e. 147) and 1419 (s.e. 196) g/day respectively, P > 0·05). A new water balance was established at about the same time, when sheep with an ileorectal anastomosis drank about 2500 ml/day more water, while losing about 2400 ml/day more water in the faeces and about 365 ml/day less water in the urine than did the control sheep. Most of the electrolyte and acid-base parameters tested were not significantly affected by the anastomosis but the concentrations of oxygen and potassium in the blood of sheep with an anastomosis were significantly lower (P < 0·001), while those of chloride (P < 0·001) and bicarbonate (P < 0·05) were significantly higher, than before surgery. These observations, together with normal blood pH values, suggest that bypassing the large intestine caused a compensated metabolic alkalosis.

Energy balance was determined on the five sheep with an ileorectal anastomosis as well as five control animals in an indirect, open-circuit calorimeter. Despite a significantly lower (P < 0·05) loss of nitrogen and energy via the urine (due to a lower output of urine) in sheep with an ileorectal anastomosis, total heat loss, whether absolute or relative to energy intake, did not differ from control values and therefore indicated that basal metabolic rate was not significantly affected.

From post-mortem examinations, anastomoses appear to have induced a marked atrophy of the bypassed caecum and colon, whilst the mass of the large intestine was significantly less than in control animals, despite the significant enlargement of the rectum. On the other hand, the small intestine appeared unaffected, either macroscopically or histologically.

The most significant physiological changes that occurred on bypassing the large intestine were related to loss of water reabsorbtion. However, good adaptation to the increased turn-over of water was evident, providing free access to water and a salt lick was allowed.

Considering economic and environmental issues is important in ensuring the sustainability of dairy farms. The objective of this study was to investigate univariate relationships between lactating dairy cow gastro-enteric methane (CH4) production predicted from milk mid-IR (MIR) spectra and technico-economic variables by the use of large scale and on-farm data. A total of 525 697 individual CH4 predictions from milk MIR spectra (MIR-CH4 (g/day)) of milk samples collected on 206 farms during the Walloon milk recording scheme were used to create a MIR-CH4 prediction for each herd and year (HYMIR-CH4). These predictions were merged with dairy herd accounting data. This allowed a simultaneous study of HYMIR-CH4 and 42 technical and economic variables for 1024 herd and year records from 2007 to 2014. Pearson correlation coefficients (r) were used to assess significant relationships (P<0.05). Low HYMIR-CH4 was significantly associated with, amongst others, lower fat and protein corrected milk (FPCM) yield (r=0.18), lower milk fat and protein content (r=0.38 and 0.33, respectively), lower quantity of milk produced from forages (r=0.12) and suboptimal reproduction and health performance (e.g. longer calving interval (r=−0.21) and higher culling rate (r=−0.15)). Concerning economic results, low HYMIR-CH4 was significantly associated with lower gross margin per cow (r=0.19) and per litre FPCM (r=0.09). To conclude, this study suggested that low lactating dairy cow gastro-enteric CH4 production tended to be associated with more extensive or suboptimal management practices, which could lead to lower profitability. The observed low correlations suggest complex interactions between variables due to the use of on-farm data with large variability in technical and management practices.

Cassava is increasingly available in the United Kingdom for use in compound feeds. The trial reported here was a 2 × 4 factorial and compared dairy cow compound feeds containing nil or 400 g of cassava per kg, and crude protein levels of 100, 120, 140 and 160 g/kg, given in conjunction with grass silage.

Forty-eight Friesian cows were used in a change-over design with four periods each of 4 weeks. The trial, therefore, compared six blocks of four cows on each of the non-cassava and cassava treatments, with each cow in a block receiving a different protein level. Compound feeds without cassava had a mean barley content of 600g/kg whereas feeds with cassava had a mean barley content of 103g/kg.

There were no significant differences in milk yield (21 14 and 22·27 kg/day) or milk fat level (41·4 and 40·4g/kg milk) on the non-cassava and cassava treatments respectively (P ≤ 0·05). Differences in solids-not-fat concentration were also not significant.

Average intakes of silage were similar on each type of diet. Daily intakes of the compound feed per cow varied from 6·95kg on the non-cassava treatment to 7·08kg on the cassava treatment. This difference in compound intake was not significant. The results indicated that compound feed containing 400 g of cassava per kg perform as well as cereal-based feeds and, therefore, cassava can be considered as a satisfactory replacement for cereals up to a level of 400 g/kg in compound feeds for dairy cows.

Aboud et al (1990) found that intake and selection of sorghum stover (i.e. straw) by Ethiopian sheep increased as the ad libitum amounts offered (g/kg mass[M].day[d]) were increased from 25 to 50 and 75. The greater intakes resulted in improved growth rates. In view of the importance of goats in smallholder tropical-agriculture and the fact that goats are considered to be selective feeders, the present experiment compared the response of goats and sheep when offered increasing ad libitum quantities of sorghum stover.

Sorghum (bird-resistant variety Seredo) was grown at Melkassa in the Rift Valley. Fourteen days after hand-harversting of grain in November 1988, stover was hand-cut and transported to the ILCA Station at Debre-Zeit. The stover was chopped (tractor-mounted Alvan Blanch Maxi Chaff Cutter) and stored for one month before feeding. Twenty four Galla bucks (11-13 months old) and twenty four Ethiopian Lowand rams (14-16 months old) were used in the 2 x 3 factorial experiment with 8 replicates.

The requirements of a weaned piglet are expected to change systematically over the period 6kg-25kg. Commonly during this time animals will be offered two diets. However, initially on each diet the animal may be restricted because it's protein requirements are in excess of that supplied by the diet. Then latterly, amino acids may be oversupplied requiring deamination of the excess by the pig. This is a costly process, in terms of the energy required by the pig and commercially, in terms of food protein costs. This system also does not take into account differing individual requirements within a group of pigs due to genotype, sex, maturity and stage of growth. As a result potential benefits are to be obtained if weaned piglets can be shown to choose an adequate diet, meeting their individual requirements, when given a choice of feeds.

Dominance allows animals priority of access to resources when these are limited. It is common practice to feed dry sows once or twice daily a relatively small amount of food. This can lead to high competition for food, when there are no provisions for individual feeding of group housed sows. In contrast, competition for food should be low when offered ad libitum. This study was designed to investigate the effect of feeding regime on the measurement of hierarchies in group housed dry sows.

Four groups of 12 multiparous sows were housed in deep straw pens (3.1 m2/sow). Two groups were offered a high fibre diet ad libitum from a three-space hopper (LC) and two groups were floor-fed 3 kg/sow of a standard diet once daily (HC). The diet composition is given in Brouns et al (1992).

Groups were allocated to treatment after service. After two months on treatment, the dominance of every sow in each pen was determined in a feed competition test between all possible dyads of sows. A more detailed description of this test is given in Brouns et al (1992). The results of this test indicated how many pen mates each sow dominated (DR). This was used to calculate an index of linearity for the hierarchy (Appleby, 1983) giving a value between 0 and 1, where 1 indicates a completely linear hierarchy.

Feeding different groups of 1 year-old prepubertal female rainbow trout for 0, 4, 8 or 12 months on either high (1.0% body weight day-1) or low (0.4%) rations produced significant changes in fecundity, total egg volume and in the percentages of fish which spawned. Fish fed high ration for the first 4 or 8 months of the year-long cycle had up to 56% higher fecundities even after weight influences had been partitioned by covariance analysis. Groups of fish fed high ration for the first 4 months of the cycle included the highest percentages of spawning fish. By optimising feeding regimes commercial hatcheries could produce up to 3x more eggs from existing stocks.

Two rearing experiments were carried out to study the effect of omitting three feeds per week from an early-weaning system on the performance of 110 male calves. From the third week the calves in the experimental groups received only one feed of milk substitute on Saturdays, at 11.00 hr; on Sundays they received no milk substitute at all; from Monday to Friday they were fed twice daily. The animals in the control groups received milk substitute twice daily during the 7 days of the week, quantity per feed being the same as for the experimental groups.

The calves were weaned at 8 weeks in experiment 1 and at 5 weeks in experiment 2.

In both experiments the calves in the control group had a significantly higher daily gain than the experimental calves during the third to the fifth weeks. From 6 to 16 weeks arid for the experiment as a whole no significant difference in weight gain or feed intake were observed. The omission of three feeds per week offered considerable advantages in the saving of labour and convenience of management.

The histological characteristics of the skin of docked and undocked fat-tailed sheep were studied at 15-day intervals between birth and 90 days of age, then every 30 days until 180 days and every 3 months until 1 year of age. Data presented in this paper were recorded at birth, 30, 60, 120,180 and 360 days of age. The fleece characteristics were studied at 1·0,1·5 and 2·0 years of age.

The skin structure was similar in docked and undocked Rahmani sheep and did not differ from that of other breeds of sheep.

The effect of docking was significant at most ages of the study on internal diameter of primary follicles and on the external and internal diameters of secondary and on average diameters of wool follicles (P < 0·05). The effect of docking was highly significant on each of staple length and wool diameter.

Eight sets of identical twin heifers and their first three calf crops were used to determine effects of single-trait selection for blood serum insulin-like growth factor 1 (IGF-1). Twin heifers were offspring of Simmental sires and Hereford × Simmental or Hereford × Angus dams. All 16 heifers were mated with the same Simmental bull in each year of the study to produce calves born in 1989, 1990 and 1991 (no. = 16, 13 and 10, respectively). Although differences were noted in performance of progeny from the four twins with the highest v. the four with the lowest IGF-1 concentrations, they zoere not large enough to recommend single-trait selection for blood serum IGF-1 in beef heifers.

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.

This study assessed milk productivity, demographic characteristics and workload distribution on a single high-yield dairy ewe farm in Spain (Avila, Spain; continental climate, latitude of 40.90 N, altitude of 900 m) over a 7-year period considering a transition from a herd management system involving five lambings per year (5LY) to a system involving 10 lambings per year (10LY). The 5LY system was practiced on the farm from 2010 to 2012 and the 10LY system from 2014 to 2015, with 2009 and 2013 being considered transition years. During this period, 27 415 lactations were recorded from an average of 3746 Lacaune sheep/year. Several productivity parameters were higher in 2014 to 2015 than in 2010 to 2012: milk yield/lactation (370±156 v. 349±185 l), lactation length (218±75 v. 192±75 days) and dry period length (53.5±38.3 v. 69.1±34.8 days) (all P<0.0001). During 2014 to 2015, investment in new lambing facilities was possible, workload was distributed more uniformly throughout the year, workload per worker was smaller, rate of ewe culling was lower (35.39±0.53% v. 42.51±7.51%), ewe longevity was greater and higher-order lactations were more numerous (P<0.0001). On the other hand, during 2010 to 2012, daily production was higher (1.73±1.66 v. 1.70±0.62 l/day; P=0.038), the interlambing period was shorter (283±50 v. 302±44 days; P<0.0001) and lambings/ewe per year were greater (1.42±0.01 v. 1.30±0.01; P<0.05). These results suggest that a 10LY herd management system can be compatible with profitability, productivity and good animal and worker’s welfare on a high-yield dairy farm, and may even be associated with better outcomes than a 5LY system.

Freezing/thawing procedures induce enhanced reactive oxygen species (ROS) formation in mammalian sperm and these ROS may be a cause for the decrease in sperm function following cryopreservation. In the present study, we used a chemiluminescence method to detect ROS-induced damage in goat spermatozoa. Iron-induced luminescence of fresh and frozen/thawed sperm cells was assessed using a luminometer. It was shown that the freezing/thawing procedure had a significant effect on some luminescence parameters. Semen freezing significantly increased the values of integral, peak max, T.half (rise) and T.max (peak) parameters. A significant correlation was observed between the percentage of motile spermatozoa and integral, peak max and T.half (rise) parameters. In conclusion, the results of the present study indicate that measurement of induced luminescence can be an alternative, sensitive and relatively simple method for assessing the effect of cryopreservation on oxidative damage to spermatozoa.