bluuebunny/crossref_metadata_2025_split huggingface dataset:
Partition of food intake between maintenance and gain among bovine sex phenotypes
Authors: Gettys T. W. , Henricks D. M. , Burrows P. M. , Schanbacher B. D. 
Published: September 2010

ABSTRACTFour groups of calves (10 bulls, 10 steers, 10 heifers and 10 ovariectomized heifers) of Simmental- Hereford breeding were individually given a high-energy diet from 10 to 16 months of age. At the end of the experiment, the 9-10-11th rib section was dissected into fat, lean and bone and chemical analysis was performed on the dissected soft tissue. For each group, the relationship between food intake and change in body weight was examined by a method designed to separate intake into its simultaneous maintenance and gain components: least-squares estimates for the maintenance coefficient (βm, kg/day per kg body weight) and the gain coefficient (βg, kg food per kg gain) were obtained for each animal. Conventional measures of food conversion ratio (kg food per kg gain) were examined on both common age and common weight-gain bases. Bulls, followed by steers, accumulated the most lean and least fat while heifers and ovariectomized heifers accumulated the least lean and most fat. Maintenance coefficients (βm) were lower in males than in females but did not differ within gender. Gain coefficients (βg) did not differ among the groups, although the coefficients appeared to be similar within gender. Food conversion ratio computed over a common age interval did not differ among groups. Food conversion ratio computed over common weight intervals was lowest in bulls followed in increasing order by steers then the two female groups. It is concluded that males grow more efficiently than females while accumulating more lean and less adipose tisue and that this greater efficiency is achieved by consuming less food per unit of body weight for maintenance, leaving proportionately more of the total intake available for gain.
The influence of different doses of oestradiol benzoate on the attainment of puberty in the gilt
Authors: Yang H. , Rodway R. G. , Varley M. A. 
Published: September 2010

ABSTRACTForty Large White ♂ × (Large White (f × Landrace ♀) pre-pubertal gilts were used to study the influence of five different doses of parenteral oestradiol benzoate (OB) on the attainment of puberty. Five gilts from eight litters were treated at 140 days of age with either 5, 10, 15, 20 or 25 μg OB per kg body weight (BW). The doses were split equally into three bolus injections given on consecutive days. Daily boar contact commenced on the day that the first oestrogen injection was given and continued until the gilts were mated. All gilts were slaughtered at either 20 days post coitum or at 235 days of age for those gilts not exhibiting a second oestrus.The numbers of gilts which ovulated within 10 days after OB injection were: 5/8, 7/8, 8/8, 6/8 and 5/8 for treatments 5 ng/kg BW through to 25 fig/kg BW, respectively. These differences were not significant (P > 0·05). The duration of behavioural oestrus after OB injection was positively correlated to the dose of oestrogen administered (r = 0·98, P < 0·01). There were no significant differences in age at puberty between treatments, and no significant differences were found in the subsequent reproductive performance.
The influence of boar-component stimuli on puberty attainment in the gilt
Authors: Pearce G. P. , Hughes P. E. 
Published: September 2010

ABSTRACTTwo experiments employing 72 and 48 pre-pubertal Large White ♂ × (Large White ♂ × Landrace ♀) gilts respectively were carried out to investigate the involvement of various boar stimuli in the induction of precocious puberty in the gilt. Experiment 1 consisted of the following treatments commencing at 165 days of age: (1) contact with an androgenized, castrated male; (2) contact with an androgenized castrated male plus a recording of boar chants; (3) as treatment (2) plus exposure to a solution of 16-androstene steroids, 3α-androstenol (5α-androst-16-en-3α-ol) and 5α-androstenone (5α-androst-16-en-3-one); and (4) contact with an entire boar. In experiment 2, additional exposure to boar urine occurred in treatments (2) and (3).Exposure of gilts to tactile, visual and auditory cues from the boar had little effect on puberty attainment. The additional exposure to 16-androstene steroids did stimulate puberty but was not as efficacious as boar exposure. Additional exposure to boar urine improved the puberty-stimulating effect of the castrated males, and further additional exposure to 16-androstenes produced a response approaching that obtained by boar exposure.These results confirm the involvement of olfactory cues from the boar in stimulating puberty in the gilt. The olfactory cues appear to be 16-androstene steroids present in boar saliva and some undefined compound(s) present in boar urine. These experiments suggest that olfactory stimuli from the boar require the simultaneous exposure to tactile and possibly also visual and auditory cues from the boar in order to stimulate the onset of puberty in the gilt.cues from the mature boar are also involved in mediating the stimulation of puberty. Exposure of gilts to isolated sources of androstene pheromones was ineffective in stimulating puberty (Kirkwood et al., 1983), whereas exposure to contact with a sialectomized boar order to stimulate the onset of puberty in the gilt.
Muscle cellularity and birth weight
Authors: Handel S. E. , Stickland N. C. 
Published: September 2010

ABSTRACTA study of the effects of low birth weight on muscle cellularity was performed on 48 pedigree Large White pigs selected, from a total of 17 litters, on the basis of their weight at birth. Where possible, the largest male (mean birth weight of 1544 g), smallest male (1135 g), and runt (776 g) littermates were chosen. Fresh frozen, whole mid belly, sections of m. semitendinosus and samples of m. trapezius from each animal were stained for the demonstration of acid pre-incubated myosin adenosine triphosphatase. The use of this stain demonstrated groups of positively stained, slow-contracting, myofibres which were each surrounded by a compliment of negatively stained, fast-contracting, fibres which together constituted ‘metabolic bundles’. The positions of metabolic bundles are indicative of the presence of single primary myofibres in the foetal muscle, all the other myofibres in the metabolic bundles being derived from subsequently formed secondary fibres. Determination of total myofibre number and primary fibre number were made for m. semitendinosus together with an estimation of the secondary to primary fibre-number ratios for both this muscle and for m. trapezius. Low birth weight was associated with a permanently reduced total muscle fibre number, proportionately in the order of 0·19 (P < 0·001) between large and runt littermates. A reduced muscle fibre number was not always associated with low birth weight, but when this was the case it was generated through a reduced secondary to primary fibre-number ratio (P < 0·01). Primary fibre number was not significantly affected in low birth-weight pigs except in extreme cases of runting.
A preliminary report on the energy intake and growth rate of early-weaned camel (Camelus dromedarius) calves
Authors: Degen A. A. , Elias E. , Kam M. 
Published: September 2010

ABSTRACTDromedary camels (Camelus dromedarius) inhabit and are well suited to semi-arid and arid areas of north Africa, south-east Asia and India. Little attention has been given to their husbandry although they are an important livestock species in some areas. One of the limiting factors in camel production is the 2- to 3-year interval between calvings. In this study, three female calves (birth weight 32·5 kg) were weaned onto artificial milk 30 days after birth and the she-camels (400 to 500 kg) were mated 10 to 14 days later. Between 30 and 120 days of age the calves received mainly artificial milk and between days 120 and 180 they received concentrates and lucerne hay. While the calves sucked milk, intake averaged 6·9 l/day, metabolizable energy intake (MEI) averaged 19·5 MJ/day and average daily gain (ADG) was 0·87 kg. Ratios of conversion of milk intake (l/day) and MEI (MJ/day) to body-mass gain (kg/day) were 8·0: 1 and 22·4: 1, respectively, and to total body solids gain (kg/day) were 22·3: 1 and 62·7: 1, respectively. From days 30 to 120, ADG was 0·67 kg, and from days 120 to 180 ADG was 0·61 kg. The calves averaged 155 kg at 180 days and ADG to that age was 0·68 kg. All three she-camels conceived 10 to 14 days post weaning.This study demonstrated that camel calves can be weaned early and that high growth rates can be achieved. In addition, she-camels can be mated shortly after parturition so that calving intervals can be reduced to 15 months.
Evaluation of British Friesian, Canadian Holstein and beef breed × British Friesian steers slaughtered over a commercial range of fatness from 16-month and 24-month beef production systems 1. Live-weight gain and efficiency of food utilization
Authors: Southgate J. R. , Cook G. L. , Kempster A. J. 
Published: September 2010

ABSTRACTThe live-weight gain (LWG) and efficiency of food utilization of purebred British Friesian and Canadian Holstein steers and of crossbred steers out of British Friesian dams by Charolais, Hereford, Limousin, Lincoln Red, Simmental, South Devon and Sussex sires were examined in two beef production systems. One was similar to the commercial 18-month grass/cereal system (16-month) and the other to a commercial 2-year system (24-month). The cattle were serially slaughtered at three levels of fatness covering the commercial range and determined by the use of the Scanogram ultrasonic machine. The trial extended over 4 years and involved a total of 650 cattle. Data for the two production systems were analysed separately. Changes in growth performance were examined relative to estimated carcass subcutaneous fat content (g/kg; SFC) and sire breed crosses compared at the mean fatness level within system: 65 g/kg SFe for 16-month and 74 g/kg SFe for 24-month.Sire breed differences were not detected (P > 0·05) in the regressions on SFe of age and live weight at slaughter, overall daily LWG and overall efficiency of weight gain. Pooled within sire breed, live at slaughter and age at slaughter increased by 2·5 kg and 2·8 days (16-month) and 2·2 kg and 2·1 days (24-month) for each g/kg increase in SFe.Charolais crosses and Canadian Holsteins were heaviest at equal SFC in both systems, but the latter were 63 days older (16-month) and 42 days older (24-month): Hereford, Lincoln Red and Sussex crosses were lightest and among the youngest in both systems.Sire breed crosses differed significantly in daily LWG: Charolais crosses grew fastest in both systems; the relative growth rate of other sire breed crosses was less consistent between the two although the Hereford crosses and British Friesians grew slowly in both systems. Overall efficiency of LWG (g gain per kg digestible organic matter intake) ranged from 164 to 205 (16-month) and 146 to 171 (24-month). Canadian Holsteins and British Friesians had the lowest efficiency of LWG in both systems of production; differences between the other breeds were not statistically significant (P > 0·05).
A comparison under temperate conditions of the nutritive value of straw for cattle following treatment using either ammonia from urea or via direct injection
Authors: Macdearmid A. , Williams P. E. V. , Innes G. M. 
Published: September 2010

ABSTRACTA series of experiments was conducted to examine the potential of using ammonia released from the hydrolysis of urea for alkali treatment of straw.In an initial experiment (1) the effect on urea hydrolysis of adding either hydrochloric acid (HC1) or the surfactant alkyl phenyl ethylene oxide to straw of differing dry matter (DM) concentration was examined. The inclusion of HC1 or surfactant failed to improve the proportion of urea hydrolysed at straw DM concentrations of 450, 600 or 750 g/kg.In experiment 2, straw was prepared and treated with urea, at a level of 20 (U2), 50 (U5), 70 (U7) g/kg straw DM and ammonia 40 (A4) g/kg straw DM to compare with untreated straw (S). Samples of the straws were milled and degradability at 60 h was estimated using the nylon bag technique. DM loss was significantly higher for all treated straws compared with untreated straw (P < 0·001). However, the proportion of added nitrogen retained from all urea treatments was less than 0·33 but U7 and U5 were approximately double that obtained from A4.In experiment 3, 3-t batches of straw equivalent to treatments U2, U7, A4 and S were treated during September and later offered to steers in digestibility and food intake trials. Straws were ground through a 40-mm screen and offered to steers in digestibility stalls, in a balanced incomplete-block design. There were increases in the digestibility of DM (+0·08 g/kg), organic matter (+0·08 g/kg), and acid-detergent fibre (+0·09) of U7 and A4 straw compared with values for untreated straw (P < 0·01).In a subsequent food intake trial treatment of long straw, with 20 g urea per kg straw DM (U2) failed to prevent moulding, however digestible organic matter intake (DOMI) of U7 and A4 straws increased by 0·42 and 0·27 kg/day respectively compared with intakes of untreated straw (P < 0·01). The application of 70 g urea per kg straw DM gave results comparable with treatment with 40 g ammonia per kg straw DM in improving digestibility of ground straw and the DOMI and preservation of long straw.
Responses of lactating ewes, offered fresh herbage indoors and when grazing, to supplements containing differing protein concentrations
Authors: Penning P. D. , Orr R. J. , Treacher T. T. 
Published: September 2010

ABSTRACTThe responses to supplements differing in protein concentration and degradability were measured in lactating ewes and their twin lambs when offered fresh ryegrass either cut or grazed. Housed Scottish Halfbred ewes, offered fresh-cut grass ad libitum received no supplement (N) or supplements with barley and maize starch (B); barley and soya-bean meal (S); barley, soya-bean meal and fish meal (SF) or barley and fish meal (F) in weeks 2 to 7 of lactation. By feeding supplements, herbage organic-matter (OM) intake was depressed (2·00 v. 1·74 kg/day). Mean daily milk yield was increased when protein supplements were given and, because milk protein concentration was higher for supplement F and similar for all other diets, mean daily milk protein output increased with increasing fish meal in the diet. Milk yields were N 2·55, B 2·59, S 3·17, SF 3·15 and F 3·17 kg/day. Total milk solids and fat concentrations were also higher for S, SF and F than N or B. Lambs from ewes supplemented with protein grew faster and the ewes generally lost less weight and body condition compared with unsupplemented ewes.At pasture, Masham ewes grazed at herbage allowances of either 4 (L) or 10 (H) kg OM per day and received no supplement (N) or supplements B or F, for the first 6 weeks of lactation and then, in weeks 7 to 12, grazed without supplements. For NL, BL, FL, NH, BH and FH respectively lamb growth rates from birth to 6 weeks were 235, 242, 274, 267, 286 and 302 g/day; from birth to 12 weeks were 210, 209, 249, 255, 275 and 287 g/day and losses in ewe body-condition score from birth to 12 weeks were 1·28, 1·22, 1·06, 0·97, 0·62 and 0·76.It is concluded that protein supplements increased milk yield and lamb growth rates and that the response tended to be greater with fish meal.
The effect of summer decline in conception rate on the monthly milk production pattern in Israel
Authors: Kahn H. E. 
Published: September 2010

AbstractA dynamic simulation model was used to predict the long-term effects of published heat stress-associated fluctuations in conception rate (CR) and milk production (MP) on the monthly MP pattern in Israel. The model results showed that the pattern of seasonal decline and rise in CR, and hence conception occurrences, produces a similar pattern of MP. This pattern closely resembles that of actual MP in Israel in 1987 and in 1988. On the other hand, seasonal correction factors for MP have no marked effect on the shape of the MP curve. These results show that in order to stabilize MP throughout the year, the prevention of seasonal (summer) decline in CR would be more effective than direct efforts to prevent seasonal MP decline.
Genetic and non-genetic factors affecting post-weaning survivability in goats
Authors: Singh D. K. , Singh C. S. P. , Mishra H. R. 
Published: September 2010

AbstractGenetic and non-genetic factors affecting survival during the post-weaning period from 3 to 12 months of age were assessed in 823 kids (217 Black Bengal, 410 Jamunapari × Black Bengal and 196 Beetal × Black Bengal) born during 1981-86. The overall survival rates during 3 to 6 and 6 to 12 months of age were 79·22 (s.e. 4·06) and 82·02 (s.e. 5·49)% respectively. Variation in survival rate during 3 to 6 months of age was significant due to season of their birth (P < 0·01) and birth weight (P < 0·05). Survival rate during 6 to 12 months of age varied due to genetic group (P < 0·01), sex (P < 0·05) and birth weight (P < 0·05). Type of birth (litter size), dam's weight at kidding and filial generation had no significant effect on survival rate during the post-weaning period. Birth weight of kids had a positive linear relationship with their survivability during post-weaning period. Summer-born kids had significantly lower survival rates from 3 to 6 months of age compared with those born in the winter and monsoon periods. Heritability estimates for survival rates during the post-weaning period were not significantly different from zero.
Effects of treatment with melatonin on the response of seasonally anovular ewes to the introduction of rams
Authors: Rekik M. , Bryant M. J. , Cunningham F. J. 
Published: September 2010

AbstractSixty-four mature ewes (equal numbers of Bluefaced Leicester ♂ × Swaledale ♀ and Suffolk ♂ × (Bluefaced Leicester ♂ × Swaledale ♀) which had lambed in March were separated from their lambs on 1 fune. They were randomly allocated from breed and live-weight blocks to one of four treatments arranged in a 2 × 2 factorial design. All received vaginal implants, with or without melatonin, on 1 June. The implants were removed, all ewes given 20 mg progesterone in oil intramuscularly and equal numbers isolated or introduced to rams on 12 July. Ovarian activity was monitored by progesterone concentrations in blood taken three times weekly from the jugular vein. Four ewes receiving melatonin and four control ewes were bled for 24 h on 6 July to determine plasma melatonin concentrations.Melatonin treatment increased plasma melatonin concentrations during the day. All ewes were anovular prior to 12 July. There were no differences between the two ewe types in their response to treatment. The number of ewes ovulating before 27 August was: control 1; melatonin 6; ram 16; melatonin + ram 16. The mean date of emulation for both the ram and melatonin + ram groups was 21 July. The number of ewes showing oestrous behaviour was 16 and 15 for the ram and melatonin + ram treatments respectively. The proportion of ewes responding to ram introduction was judged as unusually high, possibly as a result of the favourable male:female ratio. Pregnancy rate was in excess of 80% for both treatments, with resulting litter sizes of 14 for the ram and 1·8 for the melatonin + ram treatments respectively (P > 0·05).
Uniform monthly milk production in Israel by planned breeding of replacement heifers: results of a simulation study
Authors: Kahn H. E. , Lehrer A. R. 
Published: September 2010

AbstractBoth milk production (MP) and conception rate (CR) of primi- and multiparous cows (P+M) in Israel are characterized by the same summer-autumn trough and winter-spring peak. Although there is no causal link between CR and MP (a simulation-model study explained the connection), monthly CR determines the number of dry cows 7 months later, at 2 months pre-calving. Inevitably, when the number of dry cows is low, MP is high, and vice versa.Replacement heifers (RH) in Israel have a consistently high (64%) CR throughout the year. The same simulation model was used to investigate the effect of manipulated RH breeding on the herd MP pattern. When RH breeding was confined to the 3-month July to September (J-S) period during which CR is lowest for post-partum P+Ms, the monthly MP pattern in an otherwise year-round breeding dairy herd was the diametric opposite of the one produced by all-year RH breeding. When a uniform monthly quota was set for RH and P+M conceptions, and monthly RH conceptions were restricted to complement monthly P+M conceptions, the herd MP pattern became almost level. There did not appear to be any economic penalty attached to the planned RH conception system.In practice it will not be possible to adhere to a strict monthly quota of conceptions, since there is a 1 to 2 month lag between insemination and confirmed conception. Estimates of individual farm monthly CR could be used, where available. Alternatively, if 40% of all RH inseminations were performed in J-S, the MP curve would be much flatter than under the present non-planned system of RH insemination.
Responses of ewes to melatonin implants: importance of the interval between treatment and ram introduction on the synchrony of mating, and effects on ovulation rate
Authors: Haresign W. 
Published: September 2010

AbstractAn experiment was conducted to investigate the effects of the length of the interval between implantation with melatonin and ram introduction on mating patterns, and to investigate the effects of melatonin on ovulation rate and litter size in Mule ewes.Increasing the interval from treatment to ram introduction from 4 to 6 weeks was associated with a progressive and significant reduction in the time from ram introduction to mating as well as a reduction in the spread of mating across the group.Melatonin resulted in a significant and consistent increase in ovulation rate at first oestrus (+0·44 to +0·48 ovulations per ewe) across the three treated groups, although the increase in litter size (+0·19 to +0·36) was more variable.It is concluded that melatonin influences the pattern of mating and increases litter size in ewes and that the increase in litter size is accounted for by an induced increase in ovulation rate.