bluuebunny/crossref_metadata_2025 huggingface dataset:
The effects of dietary selenium on growth and selected reproductive parameters in young boars
Authors: Henson M. C. , Kattesh H. G. , Hitchcock J. P. , Kincaid S. A.
Published: September 2010

Thirty-three crossbred boars, 47 to 58 days of age, were randomly allocated to receive maize-soya bean meal diets containing 0·05, 0·15 or 0·30 mg selenium per kg. Body weights, testicular widths, and blood samples from vena cava puncture were taken at regular intervals. Libido was subjectively scored upon exposure to ovariectomized-oestrogenized gilts. Seven animals from each group were slaughtered at 9 months of age and selected reproductive structures were retrieved. Analysis of the relationships among body weight, libido and plasma testosterone levels indicated that differences (P < 0·01) existed between treatments, as analyzed over time, but that the overall treatment effect was not significant. Testicular widths were also found to be different (P < 0·05) over time. Values for all four criteria as measured over time were greater for boars fed 0·05 mg selenium per kg than for those fed 0·15 which were in turn greater than those fed 0·30. Post-mortem examination showed no treatment differences (1) in testis weights; (2) spermatozoan concentrations within the capita, corporea or caudae segments of the epididymis and (3) spermatozoan morphology examined within the caudae epididymis. Also testis lengths, weights, circumferences and spermatozoan concentrations were not significantly different between treatments. These results suggest that boars fed selenium at 0·15 or 0·30 mg/kg may exhibit some signs of retarded sexual development for a short period preceding the onset of sexual maturity
Effect of feeding level and dietary protein content on the growth, body composition and rate of protein deposition in pigs growing from 45 to 90 kg
Authors: Campbell R. G. , Taverner M. R. , Curic D. M.
Published: September 2010

1. Eight diets of similar energy content, ranging in crude protein concentration from 95 to 256 g/kg, were given at either 2·5 or 3·2 times the energy level for maintenance to entire male pigs growing from 45 to 90 kg live weight.

2. Growth rate improved with increase in feeding level and with increasing dietary crude protein up to 164 g/kg (P < 0·05). The food conversion ratio improved with each increase in dietary CP up to 186 and 164 g/kg on the lower and higher feeding treatments, respectively (P < 0·05). It was also improved with increase in level of feeding of the lower-protein diets but deteriorated with increase in level of intake of the higher-protein diets (P < 005).

3. Rate of protein deposition improved with increasing dietary crude protein up to 186 and 164 g/kg on the lower and higher feeding treatments, respectively (P < 005). The results showed that, for pigs given diets deficient in crude protein, rate of protein deposition was linearly related to protein intake (P < 0·001) but independent of energy intake. For pigs given a diet adequate in crude protein, rate of protein deposition was related to energy intake and independent of crude protein intake.

4. Body fat content at 90 kg decreased with increasing dietary crude protein up to 210 and 164 g/kg on the lower and higher feeding treatments, respectively (P < 0·05), and was increased by raising the level of intake of the higher-crude protein diets (P < 0·05). However, the influence of feeding level on body fat diminished as dietary crude protein was reduced.
Effect of active or passive immunization against steroids on reproductive performance of ewes in different levels of body condition at mating
Authors: Rhind S. M. , Morris B. A. , Clayton Jill , Doney J. M. , Gunn R. G. , Leslie I. D.
Published: September 2010

Border Leicester × Scottish Blackface (Greyface) ewes of three groups, each comprising 118 animals in a wide range of body condition scores, were mated at a synchronized oestrus in mid October. The ewes were passively immunized against testosterone (group P), actively immunized against androstenedione (group F), or not treated (group C). All ewes were slaughtered at return to service or at 35 to 45 days of pregnancy and ovulation rates and numbers of embryos present were determined. Mean ovulation rates of ewes in group P were higher than in those in group C (P < 0·05) and this difference was evident at most levels of body condition. The absolute increase in ovulation rate, compared with the control group, was similar at all condition scores. Mean ovulation rates of ewes in group F were higher than those in group C (P < 0·001) and the magnitude of the increase was greater in ewes in higher condition scores. The incidence of ova wastage was variable but differences between treatments in mean ovulation rate were generally reflected in mean litter size. The conception rates of immunized ewes were depressed compared with those of control animals, particularly in ewes with a body condition score less than 3·0 at mating. Consequently, there was no improvement in the potential lambing rate of immunized ewes following only one cycle of mating. Circulating antibody titres were not related to conception rate or body condition at mating and were related to ovulation rate only in group F ewes. It is concluded that immunization against steroids, using either passive or active techniques, can improve the reproductive performance of individual ewes but improvement in the performance of the flock as a whole may only be achieved under optimal conditions of nutrition and season.
A genetic analysis of the components of lifetime productivity in Scottish Blackface sheep
Authors: Atkins K. D.
Published: September 2010

Reproductive performance, body growth, wool production and ewe survival were examined in Scottish Blackface sheep. The data set was from a large randomly selected population maintained under hill conditions between 1954 and 1974. Paternal half-sib analyses of variance were used to estimate heritabilities and genetic correlations, while maternal half-sib analyses of variance indicated the relative importance of maternal effects (both genetic and environmental).

Among reproductive components, the heritability of fertility (ewes lambing per ewe mated) and lamb survival (lambs weaned per lamb born) were about zero. Litter size (lambs born per ewe lambing) had an estimated heritability of 0·12 (s.e. 0·04) and a repeatability of 0·22 (s.e. 0·02), indicating some scope for improvement. Additionally, the strong genetic correlation between adult body weight and litter size (0·66, s.e. 0·18) suggested greater response from a combination of indirect selection (on body weight) and direct selection (on dam's litter size). Prior to weaning, direct genetic effects on body weight were very small (heritability less than 0·1) with a large influence of maternal environment. After weaning, these maternal influences gradually diminished and the heritability of weight increased. Genetic correlations between body weights showed a similar increasing trend with age. Genetic improvement of early growth rate would be more effective by selecting on a post-weaning rather than a pre-weaning body weight. Fleece weight had a high heritability (about 0·5) but was genetically uncorrelated with other measures of performance. Ewe survival had a small genetic component although estimates of heritability were very imprecise.
Predicted and realized responses to selection for an index of bone length and body weight in Scottish Blackface sheep 2. Correlated responses in lifetime productivity
Authors: Atkins K. D. , Thompson R.
Published: September 2010

A selection experiment with Scottish Blackface sheep was used to compare predicted and realized correlated responses to selection. Three lines were maintained between 1956 and 1974 in which selection was either at random or for high and low values of an index of cannon-bone length at 8 weeks of age adjusted for body weight at the same age.

There was no evidence of asymmetrical responses in any trait. Selection for increased cannon-bone length, adjusted for body weight, resulted in (i) increased body weights at all ages between birth and maturity, (ii) increased reproduction rate, principally from increased litter size but also from small responses in ewe fertility and lamb survival and (iii) decreased survival of adult ewes. The realized genetic correlations were relatively small (up to 0·3) but mostly significantly different from zero, whereas base population genetic correlation estimates were very imprecise. The realized responses in reproduction rate were probably a consequence of the genetic response in body weight.
The effect of season and the introduction of rams on oestrous activity in Somali, Nandi, Merino, Karakul and New Zealand Romney Marsh ewes in Kenya
Authors: Carles A. B. , Kipngeno W. A. K.
Published: September 2010

A study was made of the levels of oestrous activity of two indigenous breeds of sheep (Somali and Nandi) and three exotic breeds of sheep (Merino, Karakul and New Zealand Romney Marsh) over a period of 3 years, in an equatorial environment. Breed was the only significant source of variation for the length of the oestrous cycle (P< 0·01). The mean lengths of the oestrous cycle were 17·2 (s.d. 3·21), 17·5 (s.d. 2·24), 17·9 (s.d. 2·99), 17·5 (s.d. 2·57) and 16·5 (s.d. 3·41) days for the Somali, Nandi, Merino, Karakul and Romney Marsh breeds, respectively.

The mean percentage of ewes of the different breeds showing oestrus in 20-day periods were 69·8 (s.d. 22·57), 49·9 (s.d. 18·67), 63·4 (s.d. 25·70), 79·2 (s.d. 20·30) and 33·2 (s.d. 23·50) % for the Somali, Nandi, Merino, Karakul and Romney Marsh breeds, respectively. Time-series analysis did not detect any evidence of seasonal variation in oestrous activity, although there was an indication that the Merino and Romney Marsh breeds showed a marked increase in oestrous activity following, the introduction of rams. It was concluded that the variation in level of oestrous activity was short term and random.
A note on the use of laparoscopy for intrauterine insemination of frozen-thawed semen in the ewe
Authors: Haresign W. , Read S. R. , Curnock R. M. , Reed H. C. B.
Published: September 2010

One of the major limitations to the widespread use of artificial insemination (AI) in the United Kingdom (UK) sheep industry is that with frozen-thawed semen current insemination techniques result in lowered fertility. Consequently, only fresh or liquid-chilled ram semen can be used if commercially acceptable conception rates are to be achieved.
A note on the effect of nutrition on ovulation and ovarian follicular populations in the individually fed post-partum beef heifer
Authors: Henricks D. M. , Rone J. D. , Ferrell C. L. , Echternkamp S. E.
Published: September 2010

Post-Partum anoestrus is lengthened by a thin body condition (Whitman, 1975) and malnutrition (Holness, Hopley and Hale, 1978). Post-partum nutrient intake has been implicated in both pituitary (Rutter and Randel, 1984) and ovarian (Wiltbank, Rowden, Ingalls and Zimmerman, 1964) function. Other post-partum studies, however, have shown a negligible effect of nutrition on either the pituitary (Spitzer, Niswender, Seidel and Wiltbank, 1978) or the ovary (Carstairs, Morrow and Emery, 1980). The lack of agreement among these studies may be due to an inability to control nutrient intake in all cows in a group feeding situation, or to a lack of nutrient restriction in many of the cows on a mildly restrictive diet. Furthermore, it is not clear when post-partum energy restriction is most deleterious to fertility. The objectives of this study were to examine the effect of a known individual energy intake on (i) post-partum length, and (ii) the ovarian follicular population at different stages post partum.
Effect of average daily food intake on production performance in growing pigs
Authors: Kanis E.
Published: September 2010

Effects of daily food intake (FI) on daily gain (DG), food conversion ratio (FCR), ultrasonic backfat thickness (BF), proportion of lean parts (LP), proportion of fatty parts (FP), lean tissue growth rate (LTGR), fatty tissue growth rate (FTGR) and lean tissue food conversion (LTFC) were investigated in 687 barrows and 98 gilts, slaughtered at a mean live weight of 108 kg and fattened in seven batches. In the range of food intake from about 1·7 to 3·2 kg/day (22 to 42 MJ digestible energy) a continuous distribution of data was available.

Body composition was linearly related to FI. Most regressions of BF and all of LP and of FP on FI were linear, showing fatter animals at higher food intake. For FTGR, BF, LP and FP, parameter estimates based on linear regression were given. Although the response of DG and of LTGR on increasing FI was not always significantly different from linearity, the second degree polynomials indicated diminishing returns in all batches. FTGR had a high linear correlation with FI (0·85 to 0·95), indicating that in the present range of FI a rather fixed proportion of the food was used to deposit fatty tissue.

For DG and LTGR a non-linear model of the type a(FI -fo)bwas fitted, wherefowas interpreted as maintenance requirement. For FCR and LTFC the corresponding model was FI/(α(FI —fo)b). Both models were preferred over second degree polynomials because of better interpretation of parameters. FCR and LTFC showed minima at about 2·6 and 2·2 kg/day food intake, but especially for FCR the increase at increasing FI was low. Results were not consistent in demonstrating or refuting a plateau in LTGR, which in any event appears to lie near to or beyondad libitumFI for most pigs.
Foetal development in red deer (cervus elaphus) 1. Growth of the foetus and associated tissues
Authors: Adam C. L. , McDonald I. , Moir C. E. , Pennie K.
Published: September 2010

Eighteen pregnant red deer hinds were slaughtered at known stages of gestation between 72 and 224 days (term = 233 days). The udder was removed and the gravid uterus was separated into foetal, placental, empty uterus, amniotic fluid and allantoic fluid components. Equations were fitted to the weights of each component to describe the effects of stage of gestation. Hind weight at mating had no significant effect. For the foetal weight (Y, kg) the data were closely fitted by a version of the Gompertz equation,

loge Y = 3·016 — 14·267exp (–0·01138t) – 0·086s

where t is time in days from conception and s is the sex of the foetus (male = −1, female = 1). The weights of the placenta and empty uterus were similarly fitted by versions of the Gompertz equation and mammary tissue by an exponential relationship. However, the weight of (logc) amniotic fluid was bestdescribed by a third degree polynomial, and that of (loge) allantoic fluid by a linear equation.

Using the equations and their first differentials, respectively, estimates were made of mean weights and daily rates of gain at different stages of gestation. These indicated altogether relatively slow growth and low weight of the red deer conceptus. Udder development occurred typically late in pregnancy.
Foetal development in red deer (cervus elaphus) 2. Chemical composition of the foetus and associated tissues
Authors: Adam C. L. , McDonald I. , Moir C. E. , Smart R. I.
Published: September 2010

The concentrations of dry matter (DM), crude protein (CP), fat and ash were determined for 18 singleton red deer foetuses of known gestational ages within the range 72 to 224 days (term = 233 days) and for their associated placentae and empty uteri. In addition, concentrations of Ca, P, Mg, Na and K were determined for the foetuses. The amniotic and allantoic fluids were analysed for DM, CP and ash content.

Concentrations of all measured components in the foetal fluids increased with foetal age (except for amniotic ash concentration which decreased) and linear regressions were fitted. Concentrations in the empty uterus remained constant. Given the equations previously fitted relating the weight of these tissues t o foetal age, the weights of their chemical constituents could then be calculated at various stages.

Concentrations of all measured components in the foetus increased with foetal age (except for foetal K which remained constant). In the placenta, concentrations of DM and CP tended to increase while those of fat and ash decreased. The actual weights of the chemical constituents were related to both foetal age and foetal weight by further regression analysis in the form of extended Gompertz equations.

Estimates are made of the daily rates of accretion of chemical components in the foetus and adnexa and these provide data against which to assess the additional nutrient demands of pregnancy in the red deer hind.
The effects of live weight at weaning on growth rate and carcass composition at different stages of maturity in Scottish Blackface lambs fed on two different diets
Authors: Doney J. M. , Milne J. A. , Maxwell T. J. , Sibbald Angela M. , Smith A. D. M.
Published: September 2010

The effects of live weight at weaning on carcass composition were studied with 104 Scottish Blackface lambs offered two diets differing in protein: energy ratio. Groups of lambs were slaughtered at initial live weights of 24·1 (s.e. 1·48) kg (LL) and 28·9 (s.e. 1·67) kg (IL) and at 33 kg, 38 kg, 43 kg, 53 kg and mature live weight.

Lambs were offered two diets — low protein: energy ratio (LP, 122 g crude protein (CP) per kg dry matter (DM): 10·4 MJ metabolizable energy (ME) per kg DM) and high protein: energy ratio (HP, 176 g CP per kg DM: 10·4 MJ ME per kg DM). The LP diet was offeredad libitumand the HP diet was restricted to a similar mean level. Muscle, fat and bone tissues in the carcass were separated and weighed and the carcass and non-carcass component tissues were analysed for chemical fat, protein and ash.

Daily live-weight gain (DLWG) of HP lambs (148 (s.e. 8·1) g/day) was significantly higher than that of LP lambs (118 (s.e. 8·1) g/day;P< 0·05) and food conversion ratios were lower up to a live weight of 43 kg (P< 0·05). There were no differences in intake or DLWG between LL and IL lambs. Mature live weight (73·3 (s.e. 1·79) kg) was not related to weaning weight or post-weaning diet.

There was no effect of diet on carcass composition at any slaughter weight but LL lambs had a higher fat proportion than IL lambs, which was significant (P< 0·05) at 33 kg only. During the feeding period, the increment of fat tissue per unit increase in live weight (348 (s.e. 15·8) g/kg LW) was not affected by live weight at the start of the diet. The difference between LL and IL lambs in fat proportion was directly related to the difference in weight gain required to reach slaughter weight. The difference was not a function of stage of maturity but only of weaning weight, itself largely determined by pre-weaning nutrition. At higher slaughter weights the relative difference decreased and became non-significant. Hence lambs lighter at weaning would be less suitable than heavier lambs for the production of light-weight lean carcasses.
Measuring hunger in the pig using operant conditioning: the effect of dietary bulk
Authors: Lawrence A. B. , Appleby M. C. , Illius A. W. , MacLeod H. A.
Published: September 2010

Operant conditioning was used to measure the effect on the feeding motivation (hunger) of pigs of diluting nutrient restricted food allowances with straw. Twelve Large White × Landrace boars were maintained in individual pens where they received their daily food allowance. Prior to the experiment, the boars were conditioned in separate rooms to press a panel so as to receive small rewards of food. The effect of diluting meal with straw on panel pressing was investigated in two trials. In trial 1, the boars were allocated to the following treatments: high (H) (3·5 of maintenance (A/)), low (L) (1·5 M) and low/straw (LS) (1·5 M + 0·15 times the dry weight of meal as chopped straw). This dilution increased the food volume by proportionately 0·29. Operant response rates were measured in six 1-h tests in each of two periods at the start (days 3 to 10, period 1) and at the end (days 20 to 28, period 2) of the 28-day experiment. In trial 2, nine of the above boars were allocated to the following treatments: high (H) (3·0 A/), low (L) (1·5 M) and low/straw (LS) (1·5 M + 0·30 the dry weight of meal as ground straw). This dilution increased the food volume by proportionately 0·75. Operant response rates were measured as above between days 10 to 17, following a 9-day adjustment period to the new regimes.

In both trials, operant response rate was strongly affected by treatment. Overall in trial 1, animals on the H treatment made few responses (mean 60 responses per session), animals on the L treatment made significantly more responses (mean 825, P < 0·001) and animals on the LS teatment significantly more responses yet again (1263, P < 0·05). This last difference was associated with the difficulty of the LS animals consuming all of the diluted diet during period 1. In trial 2, response rates were again higher on the L than on the H treatments. There was, however, no difference between the L and LS treatments (means: 60 v. 1035 v. 1200). Proportionately only 0·04 of the diet was refused during the period of testing.

The present results show that short-term satiety arising from gut distension does not reduce the feeding motivation of animals on chronic nutrient restriction. This suggests that hunger will remain high i n pigs on restricted food allowances, even when they have access to high fibre foods. This hunger will be a potential source of stress, particularly in housing systems involving physical restraint such as tether stalls.
A note on the milk composition of awassi ewes
Authors: Fadel I. , Owen J. B. , Kassem R. , Juha H.
Published: September 2010

Milk composition in Awassi sheep was determined in relation to time of milking, stage of lactation and age of ewe. About 80 ewes of the main flock of the Kraim Centre, were used. Fat, total solids and solids not fat proportions were not significantly affected by age of ewe, but they increased as stage of lactation advanced. With equal intervals of milking of 12 h, milk fat and total solids proportions were higher in the evening milk than in the morning milk although no differences between the morning and evening in the quantity of milk obtained were observed.
Digestive kinetics of moose (Alces alces), wapiti (Cervus elaphus) and cattle
Authors: Renecker L. A. , Hudson R. J.
Published: September 2010

Intake, rumen digesta pool sizes, ruminal digestion rates, passage rates of liquid and particle pools and faecal particle-size distrubutions of grass, browse and lucerne diets were compared in ruminally fistulated moose, wapiti and cattle. For each diet, ruminal digestion rates (nylon bag technique) were similar for the three ruminants. Intakes, rumen digesta pool sizes and passage rates varied among species and higher rates were associated with passage of larger faecal particles. However, it was not possible to simply rank the three ruminants as representative grazers (cattle), browsers (moose) and mixed feeders (wapiti) since intakes, passage rates and rumen pool sizes interacted with diet and season. Contrary to expectation, digestible dry matter intakes of each species were not greatest for their respective typical diets.
The effect of the plane of nutrition on the optimum dietary amino acid pattern for growing pigs
Authors: Wang T. C. , Fuller M. F.
Published: September 2010

Six diets based on maize and soya-bean meal were prepared. The basal diet had a crude protein (CP) concentration of 171 g/kg. The same ingredients, together with maize starch, were used to give a diet with CP 131 g/kg. This diet was supplemented with all (positive control) or with three of the four amino acids lysine, threonine, tryptophan and methionine. Each diet was given at two rates of intake. From the results, the optimum ratio between these four amino acids at different planes of intake was calculated. Amino acid digestibility in the basal diet was measured at three intakes, using pigs fitted with T cannulas at the terminal ileum.

The results showed that the optimum ratios between the four amino acids (expressed in terms of digestible amino acids) were not affected by the rate of food intake. The optimum ratio between the four amino acids (i.e. when they are equally limiting) was lysine 1·00, methionine + cystine 0-61, threonine 0·64 and tryptophan 0·20. Digestibility was not affected by the level of intake.
Effect of food intake capacity on genotype by feeding regimen interactions in growing pigs
Authors: Kanis E.
Published: September 2010

From each of 159 litters, between one and three pigs were fedad libitumand between one and four pigs were fed at several restricted feeding levels from about 27 to 107 kg live weight. Effects of litter by feeding regimen (ad libitumv.restricted feeding) interactions (L × F) and sex by feeding regimen interactions (S × F) on production traits were investigated. In experimental groups where restrictedly fed animals received an amount of food based on their estimated voluntary food intake capacity (FIC), interactions were non-significant. In groups where restricted feeding was independent of FIC, significant L × F or S × F interactions were found for daily food intake (FI), daily gain, lean tissue growth rate and fatty tissue growth rate, but not for body composition and food conversion traits.

Because of between-animal variation in FIC, restricted feeding according to a fixed scale restricted intake of some animals to a higher degree than others and degree of food intake restriction (DFR) was calculated from actual FI and FIC for animals fed at a restricted level. After correction of FI and production traits of restrictedly fed animals for differences in DFR, L × F and S × F interactions were not significant.

It was concluded that the poor relationships often found between test-station results of boars and results of their progeny in practical environments may be caused, to an important extent, by differences in DFR in each environment. To overcome these genotype by environment interactions it is recommended that animals be fedad libitumin both test and commercial environments.
Effects of protein degradability and source on rumen function, food intake and growth in Holstein cattle given high-moisture maize grain
Authors: Newbold J. R. , Rust S. R.
Published: September 2010

Crude protein concentration in diets based on high-moisture maize grain was increased using rumen degradable protein (RDP) or rumen undegradable protein (UDP). Treatment diets (numbers in parentheses indicate approximate RDP and UDP concentrations, g/kg dry matter (DM)) were: low-RDP (59, 80), high-RDP (79, 92), low-UDP (66, 67), high-UDP (69, 107, with maize gluten meal as chief UDP source) and high-UDP (71, 91, with fish, meat and maize gluten meals as UDP sources). Rumen pH and concentrations of volatile fatty acids, measured hourly for 12 h after feeding in four rumen fistulated Holstein steers, were unaffected by treatment (P > 0·05). Rumen ammonia-N concentration was greater for high-RDP (193 mg/1) than low-RDP (68 mg/1; P < 0·001). Within 12 h of feeding, ammonia-N concentration declined from 169 to 58 mg/1 for low-RDP and remained stable for high-RDP.

In a 56-day feeding trial using Holstein heifers (live weight 128 kg) and the first four treatments, RDP concentration had no effect on DM intake (P > 0·05). Lower DM intake (P < 0·01) for high-UDP (4·40 kg/day) than low-UDP (5·13 kg/day) was attributed to low palatability of maize gluten meal. Live-weight gain and food conversion efficiency were unaffected by treatment.

In a 56-day feeding trial using Holstein bulls (live weight 110 kg) and all treatments, RDP concentration had no effect on animal performance (P > 0·05). Food conversion efficiency increased (P < 0·001) when UDP concentration was increased only if UDP was supplied by a mix of fish, meat and maize gluten meals.

When RDP supply was not limiting to DM intake, protein source (amino acid composition) was better than protein degradability as an index of the feeding value of dietary protein.
The effect of source of nitrogen used for supplementation of high wheat silage diets for cattle
Authors: Brosh A. , Holzer Z. , Levy D.
Published: September 2010

Five diets of identical metabolizable energy (ME) content were formulated, in which wheat silage, made from a variety bred for a high proportion of ears to roughage, was incorporated at the rate of 480 g/kg dry matter (DM). Their calculated ME density was 11-4 MJ/kg DM, the protein concentration of four of the five diets was 150 g/kg DM, and that of the fifth was 87 g/kg DM. The effectiveness of protein supplementation of such diets by non-protein nitrogen (NPN), fish meal (FM) or soya-bean and cottonseed oil meals (SBM and CSM) was studied in a digestibility and nitrogen balance trial, and in a feeding trial using Friesian and beef breed young bulls. One diet served as a negative control (NC). The apparent digestibility of organic matter (kg/kg DM) was 0·709, 0·708, 0·704, 0·680 and 0·667 (s.e. 0·0125) and nitrogen retention (g/kg M0·75 per day) was 0·20, 0·65, 0·65, 0·64 and 0·68 (s.e. 0·059; P < 0·01) for the NC, NPN, FM, CSM and SBM supplemented diets, respectively. The feeding trial was divided into two periods; the first 100 days, and from day 101 to slaughter. The NC groups of both breeds gained significantly less in both periods of the experiment than did the supplemented groups. There were no significant differences among the supplemented groups.
Enzyme supplementation of broiler chicken diets based on cereals with endosperm cell walls rich in arabinoxylans or mixed-linked β-glucans
Authors: Pettersson D. , Graham H. , Åman P.
Published: September 2010

The efficacy of an enzyme preparation added to barley and rye-based diets given to broiler chickens and containing both β-glucanase and arabinoxylanase activities, was investigated and compared with a well characterized commercial enzyme preparation containing predominantly P-glucanase activity.

Both enzyme preparations significantly improved body weight, cumulative food intake and food conversion efficiency for chickens given both barley- and rye-based diets. For the barley-fed chickens, on average a notable increase in body weight of 171 g at day 13 and 477 g at day 24 was noted, for both enzyme preparations. However, the preparation containing high amounts of both β-glucanase and arabinoxylanase activities was more effective in reducing the incidence of sticky droppings for rye-fed chickens, and, in comparison with previously published data, gave an optimal response at a lower supplementation rate. The results indicate that it is possible to reduce the protein content in enzyme-supplemented broiler chicken diets.
Effect of supplementary crude protein level and degradability in grass silage-based diets on performance of dairy cows, and digestibility and abomasal nitrogen flow in sheep
Authors: Cody R. F. , Murphy J. J. , Morgan D. J.
Published: September 2010

Four concentrate supplements differing in crude protein (CP) and undegradable protein (UDP) content were offered to 16 lactating Friesian cows together with grass silage (dry matter (DM) 196 g/kg, pH 4·38, CP 160 g/kg DM, in vitro DM digestibility 0·68)ad libitumin a Latin-square trial with 3-week periods. The supplement treatments were: (1) barley 122 g CP per kg DM, degradability (dg) 0·77; (2) barley/soya-bean meal 210 g CP per kg DM, dg 0·69; (3) barley/soya-bean meal/fish meal 190 g CP per kg DM, dg 0·61; (4) barley/soya-bean meal/fish meal 219 g CP per kg DM, dg 0·59. Supplements were given at 8 kg/day. Total daily intakes of silage (kg DM), CP and UDP (g) on treatments 1 to 4 were 7·77, 2087, 375; 8·35, 2804, 655; 8·29, 2676, 717; 8·70, 2917, 826, respectively. Milk yield (kg/day) and yields of fat, protein and lactose (g/day) on the four treatments were 21·3, 791, 617, 984; 23·0, 816, 688, 1055; 23·0, 818, 696, 1050; 23·6, 813, 735, 1071 for treatments 1 to 4 respectively. Yield and concentration of protein and lactose were significantly lower on treatment 1 than on the other treatments, while the of blood metabolites indicated treatment effects on blood glucose, non-esterified fatty acids, plasma protein and urea. Digestibility of organic matter and non-ammonia nitrogen (NAN) flow to the abomasum (g/day), measured in sheep given a fixed silage/supplement ratio at maintenance, were 0·81 and 18·4, 0·81 and 20·8, 0·82 and 21·4, 0·82 and 22·4 for treatments 1 to 4 respectively. The NAN flow was significantly greater on treatment 4 than on treatment 1.
Relationships between sires' transmitting ability for production and daughters' production, food intake and efficiency in a high-yielding dairy herd
Authors: Persaud P. , Simm G. , Parkinson H. , Hill W. G.
Published: September 2010

Milk production and food intake records were available on individual animals from a high-yielding Holstein-Friesian herd in which selection had been practised on fat plus protein yield using nationally available artificial insemination sires. The relationship between sires and maternal grandsires' transmitting ability (ICC), expressed as a pedigree index (sire ICC + 0·5 maternal grandsire ICC), and offspring performance for milk production traits, food intake, and gross efficiency (milk energy (MJ)/total energy intake (MJ)) was investigated. The data comprised 475 26-week (data set 1) and 293 38-week (data set 2, a subset of 1) records, and for each data set analyses were conducted on heifers, cows and pooled lactations. Regressions of fat plus protein yield, fat yield, protein yield, and milk yield on their corresponding pedigree index were not far from the theoretical expectation (for a full lactation) of 1, for heifers (0·71 (s.e. 0·20), 0·72 (s.e. 0·20), 0·74 (s.e. 0·21) and 0·75 (s.e. 0·19), respectively), but slightly lower for the pooled lactations (0·57 (s.e. 0·20), 0·55 (s.e. 0·20), 0·67 (s.e. 0·19) and 0·64 (s.e. 0·15)) in data set 1. Regressions of fat plus protein yield, food intake and gross efficiency on pedigree index for fat plus protein yield, each trait expressed as a ratio of herd mean, were 1·31 (s.e. 0·37), 0·38 (s.e. 0·19) and 1·04 (s.e. 0·35) for heifers and 0·89 (s.e. 0·31), 0·48 (s.e. 0·18) and 0·59 (s.e. 0·26) respectively, for pooled lactations, in data set 1. Regressions for cow lactations were lower. Similar results were obtained with data set 2. In this study, a genetic increase of proportionately 0·1 in fat plus protein yield of daughters of sires of high genetic merit for fat plus protein yield, was accompanied by a proportional genetic increase of 0·029 in food intake and a 0·079 proportional genetic increase in efficiency.
The chemical composition of sows during their first lactation
Authors: Mullan B. P. , Williams I. H.
Published: September 2010

It is common for sows in commercial practice to lose body weight during lactation and if the loss is excessive then performance may be impaired. However, there is little information on the composition of this loss of body weight. In a 2 × 2 factorial experiment gilts were given daily either 2·7 (H) or 1·5 (L) kg food during gestation and either a high (H) (mean intakes of 3·4 and 4·9 kg/day for the H-H and L-H groups, respectively) or low (L, 2·0 kg/day) food intakes during a 31-day lactation. Seventy-three animals were slaughtered at various stages over all treatments and body composition determined by chemical analysis. The content of lipid (Li, kg) and protein (Pr, kg) in the empty body were closely related to live weight (LW, kg) and depth of backfat measured by ultrasound (P2, mm); Li = 0·381 LW + 1·042 P2 - 31·099 (R = 0·95) and Pr = 0·11 LW - 013 P2 + 4·46 (R = 0·67). Prediction equations were used to predict the composition of animals from a previous experiment (Mullan and Williams, 1989). Increasing food intake prior to farrowing increased the amount of lipid (67 v. 38 kg), protein (20 v. 17 kg), water (73 v. 63 kg) and ash (5 v. 4 kg) in the empty body at farrowing. For sows given 2·0 kg/day food during lactation about half of the total loss of body weight was lipid (835 and 570 g/day for the H-L and L-L groups, respectively) and proportionately 0-10 was protein tissue (165 and 125 g/day, respectively). When sows were fed to appetite the heaviest animals lost both lipid (520 g/day) and protein (130 g/day) whereas animals in the L-H group maintained their lipid reserves but lost 65 g protein per day. This study demonstrates the considerable amounts of lipid and protein which may be mobilized by the sow during lactation to buffer the nutritional stress through a low intake of food. The body composition of the sow during the first lactation can be accurately predicted from live weight and depth of backfat.
A note on the nutritive value and acceptability of peat in the diet of lambs
Authors: Enueme J. E. , Waibel P. E. , Goodrich R. D.
Published: September 2010

Lambs were fed diets in which peat replaced equivalent alfalfa hay. Gains were depressed by proportionately 0·14, 0·32 and 0·56 due to 100, 200 and 300 g peat per kg, respectively, during a 63-day feeding period. Lambs fed peat required more dry matter per unit gain. Necropsy examination of heart, kidney, liver, spleen, lung, and pancreas revealed no gross abnormalities from feeding of peat. Rib eye area was reduced at 200 and 300 g dietary peat per kg. There were no differences in taste of cooked loin sections due to peat. These studies support the safety of feeding peat for use as a dietary carrier at 20 to 30 glkg diet or as a dietary diluent at higher levels.
Genetic and phenotypic evaluation for reproductive performance of Egyptian buffaloes
Authors: Khalil M. H. , Mourad K. A. , Mohamed M. M. , Owen J. B.
Published: September 2010

An analysis of cow reproductive traits was carried out on 2057 lactation records of Egyptian buffaloes. A total of 651 daughters (paternal half-sisters) of 82 sires were available for the analysis. Reproductive traits analysed were age at first, second and third calving (AC), number of services per conception (NSC), gestation length (GL) and calving interval (CI). Year of calving affected most reproductive traits (P< 0·001) while no important differences were detected among months of calving. Means of NSC, GL and CI decreased linearly (P< 0·01) as parity advanced. Age of cow at calving exerted a pronounced effect (P< 0·001) on NSC and CI. There was no systematic change in the estimates of heritability and sire components of variance for reproductive measures over the first three lactations. Heritability estimates for NSC and GL in the different parities were generally low, ranging between 0·04 and 0·18, while moderate estimates for AC and CI were obtained. Phenotypic correlations between reproductive traits were positive and relatively moderate or low. For most traits, positive and relatively high or moderate estimates of genetic correlations were observed. Mating bull was found to be an important source of variation for reproductive performance of Egyptian buffaloes. The highly significant effect of mating bull on reproductive traits could be considered as evidence for the importance of evaluating bull semen quality before the mating of cows
Prolonged administration of a β-agonist, salbutamol, to lambs does not impair metabolic or endocrine responses to the stress of dipping
Authors: Bassett J. M. , Bowman A. S. , Hanson C. , Rodway R. G. , Speed P.
Published: September 2010

Previous studies in foetal and growing sheep have shown that prolonged administration of β-agonist drugs leads to selective but marked attenuation of cardiovascular, metabolic and endocrine responses to the natural catecholamine hormones adrenaline and noradrenaline, as well as attenuation of responses to the drug itself. The experiment reported here was carried out to determine whether administration of the β-agonist drug, salbutamol, by twice-daily intramuscular injection at rates of 40 or 200 μ/kg per day, for a period long enough to result in substantial attenuation of its metabolic and endocrine effects, might also result in impairment in the ability of treated animals to respond to stressful husbandry procedures which disturb metabolic homeostasis and which depend on increased sympathetic nervous and adrenal activity for the restoration of homeostasis. Serial blood sampling on day 1 and day 14 of salbutamol treatment showed that the large increases in plasma lactate and glucose observed on the 1st day were absent on day 14, while the rapid increases in free fatty acids and insulin observed on day 1 were very greatly attenuated. Daily blood sampling also demonstrated that salbutamol, like cimaterol, significantly decreased both pre- and post-feeding plasma insulin and glucose concentrations.

Metabolic and endocrine changes consequent on herding and immersion of the lambs in a sheep-dip, were unaltered by 14 days of salbutamol treatment, even though the procedure resulted in activation of the pituitary-adrenal axis as evidenced by increased β-endorphin and cortisol concentrations, and a large increase in plasma lactate concentration. These results suggest β-agonist-treated animals can respond normally to physiological stresses but further investigations remain necessary to determine whether responses dependent on increased lipid mobilization and shivering, such as shearing or prolonged exposure to severe cold, remain normal in β-agonist treated animals.
A note on the effect of white-flowered peas on sow reproductive performance
Authors: Ogle R. B. , Annér K.
Published: September 2010

The effect on sow reproductive performance of including 100 g white-flowered peas (Pisum sativum hortense, cv. Vreta and Lotta) per kg, replacing barley, wheat and soya-bean meal in gestation and lactation diets, was studied over four parities using 24 pairs of crossbred littermate sows. Net sow weight gains and changes in backfat thickness over the complete reproductive cycle were similar for both treatments. Piglet live-weight gains and mean litter size at birth were not influenced by treatment, although litter size at weaning was 0·5 pigs higher (P > 0·05) for the control sows, due to higher post-natal mortality rate in the litters from the sows given the pea diets. It can be concluded that inclusion of white-flowered peas at a rate of 100 g/kg had no adverse effect on reproductive performance, with the exception of slightly higher post-natal piglet mortality.
The effect of supplementation with protein, lipid and propionate on nutrient partitioning in roughage-fed lambs
Authors: van Houtert M. F. J. , Leng R. A.
Published: September 2010

Eighty castrated male lambs were allocated to either an initial slaughter group (no. = 16) or one of eight treatment groups (no. = 8). Ammoniated barley straw was offered ad libitum. This was supplemented with sodium (Na) propionate (0 or 20 g/day), formaldehyde-treated casein, (protected casein, 0 or 50 g/day) and/or calcium (Ca) salts of long-chain fatty acids (Ca soap, 0 or 30 g/day), as a factorial design. Measurements were made of food intake, live-weight gain and wool growth, rumen fluid parameters and changes in body composition over a period of 155 days.

Food intake (g dry matter per kg live weight) was lower in the groups supplemented with Ca soap and Na propionate. Fleece-free live-weight gain was increased by supplementation with protected casein and Ca soap, but was not affected by Na propionate. Supplementation with protected casein increased wool yield. Adjusted means for water, protein and ash content of the body (adjusted to mean fleece/digesta-free body weight at slaughter of 27·1 kg) were affected significantly by the second-order interaction between the supplements. Adjusted body water and protein mass were lower when Na propionate was given alone or with Ca soap and protected casein. Fat mass tended to be higher under those conditions. Supplementation with Ca soap increased adjusted fat and gross energy contents and decreased adjusted protein and water mass. Supplementation with protected casein decreased total body fat and increased adjusted protein mass in the body. The partitioning of water, protein, fat, ash and energy between the carcass and non-carcass residues was affected to a small extent also. These results demonstrate interactive effects of the supplements used, on nutrient partitioning in lambs offered straw-based diets.
Protein, acetate and propionate for roughage-fed lambs. 1. Body and blood composition
Authors: van Houtert M. F. J. , Leng R. A.
Published: September 2010

Sixty castrated male lambs fca. 37 kg) were allocated to an initial slaughter group (no. = 12) or to one of six treatment groups (no. = 8). Chopped oaten hay (sprayed with 10 g urea per kg) was offered ad libitum with 57 gjday chopped lucerne hay. Additional supplements were 0 or 57 g/day formaldehyde-treated casein (protected casein) and volatile fatty acids (VFAs) at ca. 1·45 MJ gross energy per day. The VFAs given were acetate or propionate or a mixture of these (molar ratio 4: 1). Daily food intake and weekly live-weight (LW) gain were measured and rumen fluid and blood were collected. The lambs were shorn, slaughtered and body composition was determined.

Food intake (g/kg LW) was not affected by treatments. Supplementation with protected casein increased LW gain and wool growth. Supplementation with propionate reduced LW gain, but not when given with protected casein. Plasma concentrations of urea-nitrogen and insulin were increased, and plasma somatotropin decreased in lambs given protected casein. Final body content of water, fat, protein and gross energy, adjusted to the mean fleece/digesta-free body weight of 36·5 kg, was not affected by the treatments. The partitioning of water, fat and energy between the carcass and the rest of the body was affected by the treatments. Excretion of VFAs in urine was measured in two sheep in experiment 2, and was negligible compared with the quantity of VFAs given. It is concluded that energy from salts of VFAs, in particular propionate, is used inefficiently for body-weight gain in lambs given low-protein roughage diets. The nutritional treatments had only marginal effects on the composition of body gain.
An empirical model for the lactation curve of white British dairy goats
Authors: Williams J. C.
Published: September 2010

A survey of dairy herds was undertaken to establish an empirical model for the goat lactation curve. The adopted model will be used to predict milk output from commercially kept dairy goats. It is also desirable for the model parameters to be easily interpretable in terms of shape and scale of the curve.

Records for 152 goat lactations from a Research Institute and 255 lactations in five commercial herds were analysed. Three groups of equations were fitted to individual goats from the Research Institute herd. The most suitable model was selected after study of residuals and consideration of the model parameters.

The adopted model was of the form: y = A exp(B(1 + n '/2)n' + Cn ‘2 – 1·01‘sol;'n) where y = daily yield in kg; n = day of lactation (post parturition); and n' = (n - 150)/100.

This model was then validated with lactation data from the five commercial herds. There was no evidence to reject the adopted model.