bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reproductive and lactational responses and serum growth hormone and insulin in fine-wool ewes treated with ovine growth hormone
Authors: Holcombe D. W. , Hallford D. M. , Hoefler W. C. 
Published: September 2010

AbstractEighteen 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.
Growth and carcass characteristics of desert goat kids and their temperate cross
Authors: Bello A. , Babiker S. A. 
Published: September 2010

AbstractCrossbreeding of desert goat does with the temperate Saanen x Toggenburg buck was found to result in a significant increase in the daily live-weight gain and the empty body weight of their progeny slaughtered at about 30 kg live weight when compared with purebred desert goat kids (P < 0·001). Food intake did not differ between the two types of kids, but live-weight food conversion efficiency was significantly superior in crossbred kids (P < 0·05).Carcass weight and killing-out proportion tended to be greater in the crossbred kids reflecting lower weights of head, skin, internal organs and gut fill. Breed types did not differ in the weights of individual wholesale cuts. Carcass dissection revealed significantly higher muscle proportion (P < 0·05), significantly lower fat proportion (P < 0·01) and higher muscle: bone ratio in the crossbred kids.
A comparison of undried and dried fish-protein hydrolysate as a protein source for calf milk replacers
Authors: Petchey A. M. , Owen J. B. , Mackie I. M. , Ritchie A. H. , Ørskov E. R. 
Published: September 2010

ABSTRACTMilk replacers in which skim milk protein (SMP) was replaced in various proportions by undried or dried fish protein hydrolysate (FPH) were offered twice daily to British Friesian male calves. Various proportions of fish protein and milk protein in the diets were obtained by mixing replacer made from SMP with replacers made from undried and dried FPH respectively. The ratios were: 100 FPH, 0 SMP; 67 FPH, 33 SMP; 33 FPH, 67 SMP; and 0 FPH, 100 SMP. Calves were offered the milk replacers only to a maximum of 5 1 per day until 28 days when concentrates and hay were offered ad libitum. The calves were weaned after 42 days. Feed intake and live-weight gain were recorded for 84 days.There was a marked decrease in performance to weaning when the milk replacer contained two-thirds or more of the FPH. The FPH-fed calves had lower hay intakes than those fed milk only. Treatment differences in post-weaning live-weight gain reflected mainly differences in concentrate intake. There was no significant difference in live-weight gain nor food efficiency for calves fed either undried or dried FPH in any period to 84 days. The number of treatments for scour was similar for the two groups. However, the calves fed dried FPH had a lower dry-matter intake in the post-weaning period.
The effects of body weight and its components on lambing performance in some commercial flocks in Britain
Authors: Geisler P. A. , Fenlon J. S. 
Published: September 2010

ABSTRACTAn analysis of the records of ewe weight and condition at mating together with subsequent lambing performance for several commercial flocks in the UK revealed no significant relationship between lambing performance and size, measured by weight transformed to a standard condition. The relationship between mating weight and body condition score at mating was linear though there was considerable variation in weight at a fixed body condition, suggesting a substantial spread in skeletal size. Increases in ovulation rate were not discernible from lambing figures over the range of body conditions observed in these flocks.
Genetic differences in milk production in relation to mature body weight
Authors: Taylor C. S. 
Published: September 2010

A survey of the accumulated experimental evidence suggests that the general effect of genetic differences in body size on input-output relationships in livestock might be largely accounted for by the following two genetic sizescaling rules:1. treat all age and time variables for the ith genotype as directly proportional to Mi0·27, where Mi is the mature body weight of the ith genotype;2. at every age standardized as in (1), treat all cumulated inputs and outputs for the zth genotype as directly proportional to Mi.
Estimation of direct additive and maternal additive genetic effects for weaning weight in Mashona cattle of Zimbabwe using an individual animal model
Authors: Khombe C. T. , Hayes J. F. , Cue R. I. , Wade K. M. 
Published: September 2010

AbstractWeaning weights (or weight nearest to 205 days of age) from 8086 Mashona calves were collected from seven herds covering the period 1976 to 1988. Estimates of (co)variance components were obtained by restricted maximum likelihood using a derivative free algorithm and fitting an individual animal model. Estimates of direct additive heritability, maternal additive heritability, their correlation, total heritability and repeatability, obtained under two models were 0·243 and 0·281, 0·113 and 0·392, –0·282 and –0·269, 0·252 and 0·298, and 0·409 and 0·573, respectively. Trends within herd were estimated from the mean value of progeny born within a particular year. There were no significant trends in direct additive breeding values. A general decline in maternal breeding values was observed. Only one herd (herd 1) had a significant eroiyonmeYital freni (0·385 kg/year). It IMS emphftsilfiti that any future revision of the method used to improve the weaning weights of beef cattle should also improve their maternal breeding values.
Metabolic responses to hyperinsulinaemia under glucose-potassium-amino acids clamp in lactating and non-lactating goats
Authors: Tauveron I. , Debras E. , Tesseraud S. , Bonnet Y. , Thiéblot Ph. , Champredon C. , Grizard J. 
Published: September 2010

AbstractThe present experiment was undertaken to investigate adaptations to insulin action on metabolism during lactation by using plasma concentrations of β hydroxybutyrate (β OH) free fatty acids (FFA) and lactate (L) as indicators. The study included three groups each of four goats. One group was used at 12 to 31 days post partum (early lactation), one group at 98 to 143 days post partum (mid lactation) and one group at 1 year post partum (dry period). For a given physiological state, each goat was examined four times to study the effect of insulin infused for 2·5 h at two rates, medium (0·36 nmol/min) followed by high (1·79 nmol/min) in two protocols: under normal aminoacidaemia in study 1 followed by hyperaminoacidaemia in study 2. Appropriate amino acid infusions were used to blunt insulin-induced hypoaminoacidaemia under eukaliaemic and euglycaemic clamp conditions or to create hyperaminoacidaemia and maintain this state under insulin treatment. In the basal state βOH (P < 0·05), mid lactation) and FFA (P < 0·05 early lactation) were higher during lactation than in the dry period. Plasma L was unmodified. Insulin infusion always resulted in a decrease in βOH levels (P < 0·05). In both studies, the change in βOH concentration as a function of changes in plasma insulin (an index of insulin sensitivity) was greater during early lactation than in the dry period (P < 0·05); this was also the case of mid lactation in study 1. Insulin infusion decreased plasma FFA during early lactation and in the dry period in study 1 (P < 0·05), and there was a trend for insulin sensitivity to be greater during early lactation. In both studies insulin infusion did not affect plasma L in lactating goats whereas plasma L was increased in dry animals (P < 0·05). The results demonstrate that during early lactation, compared with the dry period, there is an increased ability of insulin to lower βOH and FFA concentrations. These effects were not altered by increasing plasma amino acid concentrations during insulin infusion.
A simulation study of open nucleus and closed nucleus breeding systems in a sheep population
Authors: Roden J. A. 
Published: September 2010

AbstractStochastic simulation was used to compare the results of alternative breeding systems in a sheep population divided into 10 flocks of 120 ewes. The breeding systems compared were selection within closed flocks (CF), a closed nucleus system (CNS), an open nucleus system (ONS) and open nucleus systems with the selection of nucleus replacements being restricted to either nucleus born males (ONSRm) or nucleus born females (ONSRf). Selection was for a best linear unbiased prediction of breeding value for lamb live weight which had a heritability of 0·17. The open nucleus breeding systems (ONS, ONSRm, ONSRf) resulted in higher rates of genetic gain, more predictable selection responses and lower rates of inbreeding than either the closed nucleus system (CNS) or selection within closed flocks (CF). Initial genetic differences between flocks resulted in higher rates of genetic gain in the nucleus breeding systems due to the use of between flock genetic variance. In the ONS system up to 25% of nucleus sires and approximately 50% of nucleus dams were born in base flocks. Nevertheless if selection of either nucleus sires or dams was restricted to nucleus born animals there was very little change in genetic gain or rate of inbreeding.
Bromocryptine is effective in reducing milk production in ewes during lactation, but has no additional effect during drying off
Authors: Buys N. , Vanmontfort D. , Peeters R. , van Isterdael J. , Decuypere E. , Kühn E. R. 
Published: September 2010

AbstractThe effect of bromocryptine on milk production was investigated in 32 crossbred ewes (Flemish Milksheep х Suffolk) with one sucking lamb, during lactation and during drying off. After weaning the lambs, all ewes were hand milked twice daily for 3 days. From day 4 onwards, the ewes were divided into four groups with equal mean daily milk production. Ewes of groups A and B were hand milked twice daily during the following 9 days. Ewes of groups C and D were dried off by reducing the milking frequency. They were milked on days 5, 8 and 12. In groups B and D, bromocryptin (1 ml of 1 g/l ethanol 50%) was injected intramuscularly twice daily while control ewes (groups A and C) received 1 ml ethanol 50%. Blood samples were taken by venipuncture prior to each injection and were assayed for prolactin, growth hormone, thyrotropin and cortisol.Bromocryptine decreased plasma prolactin levels but did not alter growth hormone or cortisol concentrations during lactation or drying off. Thyrotropin levels were elevated by bromocryptine during drying off but were unaffected during galactopoiesis.During lactation the daily milk production remained unchanged in control ewes while in bromocryptine-treated ewes a proportional decrease of 0·5 was observed. In all ewes the decrease in milk production occurring at drying off could not be accelerated or stimulated by bromocryptine.It is concluded that prolactin plays an important role in galactopoiesis in ewes but its role is comparatively unimportant compared with other factors during mammary involution.
Responses in adipocyte dimensions to divergent selection for predicted carcass lean content in sheep
Authors: Bishop S. C. , Cameron N. D. , Speake B. K. , Bracken J. , Ratchford I. A. J. , Noble R. C. 
Published: September 2010

AbstractAdipocyte dimensions of subcutaneous fat, sampled by biopsy at the 13th rib, were measured in 20-week-old rams from lines of Texel-Oxford and Scottish Blackface sheep, both divergently selected for carcass lean content. A total of 163 animals were measured, with close to equal numbers per breed-line combination. In both breeds, the high (lean) selection line had significantly lower backfat depths (0·71 mm in the Texel-Oxford and 0·83 mm in the Scottish Blackface, s.e.d. = 0·14 and 0·13 mm, respectively), but body weight did not differ between the lines. The ultrasonic fat depth differences between the Texel-Oxford selected lines were accompanied by increases in adipocyte diameter, area, diameter standard deviation within each sample and implied cell number, calculated as the ratio of ultrasonic fat depth to average adipocyte diameter. In the Scottish Blackface sheep there were no selection line differences in adipocyte dimensions, but there was an increase in implied cell number in the line selected for increased fatness. Across breeds, ultrasonic fat depth was correlated with both adipocyte diameter and implied adipocyte number (r = 0·58 and 0·75, respectively), but these latter two measurements were uncorrelated with each other.
Effects of nutrition in utero and in early life on the subsequent lifetime reproductive performance of Scottish Blackface ewes in two management systems
Authors: Gunn R. G. , Sim D. A. , Hunter E. A. 
Published: September 2010

AbstractOver 3 years, a flock of Scottish Blackface ewes was managed so that one-third of the ewes received a high level of nutrition during the last 100 days of pregnancy (P), one-third received a high level of nutrition during the first 100 days of lactation (L) and one-third received a low level of nutrition as derived from a hill grazing over the same two periods (C). From these ewes, 496 ewe lambs were retained at weaning (19 to 22 weeks of age), balanced for treatment, year and birth type. At 6 months of age half of the lambs, similarly balanced, were transferred to an upland grazing system (U) for three breeding years. The other half was retained on the same hill grazing as their mothers for the same period (H). At the end of the study, all ewes were fed to reduce the range in body condition at a synchronized mating and ovulation rates were determined at slaughter.Differences in live weight of ewes due to treatment between groups P, L and C had disappeared by 18 months. There were no pre-mating differences between treatments in live weight or body condition score except that ewes in group P had higher live weights than those in group C at condition scores greater than 2·75. There was little effect of grazing system on the differences between treatments in live weight or body condition score at 30 and 42 months but H ewes were heavier and fatter at 18 months of age. Ewe mortality was consistently less in group L than in groups P and C and on system H than on system U, although the differences were not statistically significant. Group L had fewer barren ewes than groups P and C, and barrenness was significantly greater in the U than the H system. Group C had proportionally more single than multiple births than either groups P or L.At the end of the study there were no differences between the treatments in the proportion of ewes successfully mated at the final mating nor in their ovulation rates in relation to pre-mating body condition.It is concluded that nutrition during either the lactation period or late pregnancy period can influence subsequent lifetime reproductive performance and that this was expressed through an effect on embryo or foetal loss since there were neither residual differences apparent in live weight or condition score nor in ovulation rate potential.
The responses of growing pigs, of different sex and genotype, to dietary energy and protein
Authors: Fuller M. F. , Franklin M. F. , McWilliam R. , Pennie K. 
Published: September 2010

AbstractIntact male pigs from two nucleus breeding herds (one predominantly Duroc, DM; the other purebred Large Wliite, LM) together with intact male (RM), castrated male (RC) and female (RF) commercial hybrid pigs were given one of two diets, with the same balanced protein (180 or 240 g/kg) at three daily rates, the highest being ‘to appetite‘. Six replicates of 30 pigs were allocated to these regimes at 40 kg: one replicate was slaughtered immediately to determine initial carcass composition; the remaining pigs were slaughtered at 85 kg when carcass fat and specific gravity (SG) were measured. For two replicates this was followed by dissection and chemical analysis: daily gains of carcass lipid and protein were estimated directly for these two replicates and predicted from carcass weight and SG for the other three. Fed ‘to appetite’, castrated males and females ate more than males; LM pigs ate least. All males grew faster than females or castrated males, the DM pigs the fastest, these rankings being relatively insensitive to feeding level. However, both in daily weight gain and daily protein accretion only the males responded to additional dietary protein. Daily body protein accretion of DM pigs increased linearly with intake on both diets whereas LM pigs showed little response to the highest level of feeding. At the same daily protein intake all pigs had higher rates of body protein accretion on the low protein diet, showing that they were sensitive to additional dietary energy. Results indicate that an animal's superiority may result from a greater efficiency of protein utilization or a higher lean growth potential but that these two characteristics are not simply related.
Separate and combined effects of ephedrine and caffeine on protein and lipid deposition in finishing pigs
Authors: Oksbjerg N. , Sørensen M. T. 
Published: September 2010

AbstractTwo experiments were conducted to examine the effects of dietary inclusion of an ephedrine (Eph)/caffeine (Caf) mixture on finishing (55 to 100 kg live weight) castrated male pigs. The first experiment was conducted as a dose-response study and showed that the mixture had an optimal effect on performance and carcass composition at a dietary inclusion level of approximately 56/560 mg/kg of Eph and Caf, respectively. In the second experiment, interactions between the compounds were studied by dietary inclusion of Eph (56 mg/kg) and Caf (560 mg/kg) separately or as a mixture (56/560 mg/kg). The mixture reduced food intake by 0·12 and improved the food: gain ratio by 0·08. Muscle protein deposition rate was increased proportionately by 0·25, lipid accretion rate was decreased proportionately by 0·27, and gross energetic efficiency of energy deposition decreased proportionately by 0·09. This resulted in a changed proportional carcass composition towards more muscle (0·08) and less fat (0·21) after treatment with the mixture. The reduction in food intake was sustained due to an interaction over the first 3 weeks of treatment changing to additive effects by the compounds. The increased muscle protein deposition rate after feeding the mixture was entirely due to Eph, while the decreased gross energetic efficiency of energy deposition was caused by Caf. On the other hand, both compounds contributed almost equally to the decrease in lipid accretion rate. These results show that an Eph/Caf mixture markedly improves performance and body composition in finishing castrated pigs.
On the use of opportunity costs in deriving the economic value of herd life
Authors: Groen A. F. , van Arendonk J. A. M. , Goddard M. E. , Vollema A. R. 
Published: September 2010

AbstractThis paper presents the economic perspectives applied when either using or not using opportunity costs of postponed replacement in deriving the economic value of herd life. Results show the equivalence of the rescaling method and the correction for opportunity costs. In economic terms, using rescaling or correction for opportunity costs forces the value of genetic improvement to change from revenues of increased output to reduction of costs per unit of (fixed) ouput. Under the zero profit theory, the economic value of herd life is equal when either using or not using correction for opportunity costs. In deriving economic values to define breeding goals, the choice of a method and price parameters will have to depend on foreseen future production circumstances for the system under study.