bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors affecting the outflow of protein supplements from the rumen. 1. Feeding level
Authors: Eliman M. E. , Ørskov E. R. 
Published: September 2010

ABSTRACT1. Two experiments were conducted with four sheep and four lactating Friesian cows to investigate the effect of food intake on the outflow of protein supplements from the rumen. Protein supplements treated with sodium dichromate were used.2. Dichromate treatment had little or no effect on particle size distribution or density of the protein supplements. The dichromate-treated proteins were rendered completely undegradable in the rumen and the rate of outflow of chromium-treated protein from the rumen was estimated from the concentrations of chromium recovered in the faeces.3. There were highly significant linear effects of feeding level on fractional outflow rate per h of chromium-treated protein supplements from the rumen of sheep and cows. Fractional outflow rates of chromium-treated fish meal and soya-bean meal, respectively, from the rumen of sheep were 0·0080 and 0·0076; 0·0182 and 0·0259; 0·0319 and 0·0335; and 0·0383 and 0·0385 per h at 0·2, 1·0, 1·5 and 2·0 times the energy requirements for maintenance, respectively. There were no significant differences between the two tested chromium-treated protein supplements in fractional outflow rates per h when the particle size was similar, nor any difference in particle size or density. Soya-bean meal was ground to achieve a particle size distribution similar to that of fish meal. For the dairy cows, the fractional outflow rates of fish meal from the rumen were 0·065, 0·072, 0·091 and 0·088 per h, at 1·5, 2·0, 2·5 and 3·0 times the energy requirements for maintenance.4. There were significant differences between sheep in fractional outflow rates per h of protein supplements from the rumen due to the considerably higher values obtained for one animal.
The effects of level of nutrition before and after 8 months of age on subsequent milk and calf production of beef heifers over three lactations
Authors: Johnsson I. D. , Obst J. M. 
Published: September 2010

ABSTRACTOne hundred and five Hereford heifers were reared on varying amounts of the same diet of grain and hay to grow at either high (H: 0·91 kg/day), medium (M: 0·67 kg/day) or low (L: 0·55 kg/day) rates between 2 and 8 months of age. Between 8 and 14 months, intake was restricted for half of the H heifers (HL: 0·14 kg gain per day), ad libitum for half of the L heifers (LH: 0·97 kg gain per day) and moderate for all other heifers (HM: 0·57; MM: 0·58; LM: 0·55 kg gain per day). These treatments resulted in a range of live weights at 8 (weaning) and 14 (premating) months commonly seen in commercial production. Heifers were mated with Hereford bulls at 14 months of age and subsequently grazed at pasture. Milk yields (I/day) at 30 days post partum and the 240·day sex-adjusted calf weaning weights (kg) for HM, HL, MM, LH and LM heifers in the first lactation were 4·1, 218; 4·9, 236; 4·3, 221; 5·7, 241; and 6·3, 259 respectively (P < 0·01). Calves from HM and MM cows were significantly smaller and leaner than those weaned by LM cows. Milk yields 30 days post partum and 200·day sex-adjusted calf weaning weights for the second lactation averaged: HM, 5·2 and 202; HL, 6·8 and 217; MM, 7·0 and 222; LH, 6·6 and 219; and LM, 7·0 and 229, respectively; and for the third lactation: 5·1 and 211; 6·5 and 225; 7·2 and 223; 7·4 and 230; and 7·6 and 237, respectively. The continued lower milk yield of HM cows (P < 0·05) was offset by a trend (NS) to higher fertility and lower calfmortality, particularly in the 1st and 2nd years of production. Over the three lactations studied, the number of calves weaned per opportunity and the total actual weight (kg) of calves weaned per cow kept averaged: HM, 0·86 and 573; HL, 0·66 and 465; MM, 0·68 and 466; LH, 0·70 and 512; and LM, 0·67 and 507, respectively.The high growth rates commonly achieved by autumn-born Hereford heifers under commercial grazing conditions may reduce their subsequent milk-yield potential. This potential appears to be more sensitive to level of nutrition before 8 months of age than between 8 and 14 months.
Reproductive performance of gilts induced into puberty with oestradiol benzoate or a combination of pregnant mare's serum gonadotropin and human chorionic gonadotropin
Authors: Paterson A. M. , Pearce G. P. , Foxcroft G. R. , Reed H. C. B. 
Published: September 2010

ABSTRACTThe efficacy of a single injection of oestradiol benzoate, or a combination of pregnant mare's serum gonadotropin (PMSG) and human chorionic gonadotropin (HCG), for the induction of a fertile oestrus and ovulation in the prepubertal pig was investigated in two experiments.In the first experiment, 1·2 mg of oestradiol benzoate induced 21/23 gilts to ovulate, and 22/23 gilts showed oestrus and were inseminated on day 4 or 5 after treatment. At 28 days after insemination, 12 gilts were pregnant and carrying a mean of 7·1 (s.d. 3·3) live embryos, giving an embryonic survival rate of 0·703. All the 22 gilts treated with 400 international units PMSG plus 200 international units HCG as a single injection ovulated but only 10 showed oestrus and were inseminated. At 28 days after insemination, six gilts were pregnant with a mean of 13·0 (s.d. 5·8) live embryos, giving an embryonic survival rate of 0·583.In the second experiment, 9/11 oestradiol benzoate and 10/10 PMSG/HCG gilts ovulated in response to treatment. Oestrous detection and insemination were delayed until the expected time of the second oestrus, 20 to 30 days after treatment. Nine gilts (3 oestradiol benzoate, 6 PMSG/HCG) showed oestrus in this period and eight were inseminated. Five gilts were pregnant 28 days after insemination with a mean of 11·4 (s.d. 1·1) live embryos, giving an embryonic survival rate of 0·860.
Effect of housing and temperature on metabolic rate of pregnant sows
Authors: Geuyen T. P. A. , Verhagen J. M. F. , Verstegen M. W. A. 
Published: September 2010

ABSTRACTTwelve pregnant sows, 35 to 52 days pregnant initially and 89 to 103 days pregnant at the end of the experiment, were used to study the effect of ambient temperature on metabolic rate. Six sows were group-housed in two groups of three sows per group in one calorimeter and six sows were tethered individually in another calorimeter. Temperatures were changed by 3°C every 3 days in a stepwise fashion from 20 to 8°C and from 8 to 20°C. Sows were given a constant amount of food, which gave 540 kJ metabolic energy per kg live weight0·75per day and which covered estimated needs that were proportionately 0·20 above maintenance.Average daily live-weight gain was 531 g for the group-housed sows and 402 g for those housed individually. Heat loss increased below 14°C in group-housed and below 20°C in individually-housed sows. Extra daily thermoregulatory demand was 7·5 kJ/°C in group- and 13·7 kJ/°C in individually-housed sows.
A note on methionine supplementation of pig grower diets containing lupin-seed meal
Authors: Leibholz Jane 
Published: September 2010

ABSTRACTForty entire male pigs, between 63 and 147 days of age, and weighing initially 21 kg, were given a basal diet containing 1·8 g methionine per kg, and based on wheat, sorghum and lupin-seed meal (Lupinus augustifolius cultivar Unicrop), supplemented with 0, 0·2, 0·4 or 0·6 g methionine per kg.Supplementing each kg of the basal diet with 0·2 g methionine per kg significantly increased growth rate by 105 g/day and improved efficiency of food conversion between 21 and 35 kg live weight. Increasing the supplementation of methionine to 0·6 g methionine per kg diet increased growth rate between 21 and 35 kg live weight by a further 26 g/day but did not affect efficiency of food conversion. Between 35 and 71 kg live weight, performance was not improved by supplementation of the basal diet with methionine.
Genetic and environmental effects on milk yield of Pitangueiras cattle
Authors: Lôbo R. B. , Duarte F. A. M. , Gonçalves A. A. M. , Oliveira J. A. , Wilcox C. J. 
Published: September 2010

ABSTRACTData from 5270 lactation records of 1380 cows sired by 132 bulls and recorded from 1962 to 1977 were analysed. Statistical analyses, using least squares and maximum likelihood methods, showed significant effects for genetic group, age of cow, month and year of calving, and lactation length. Overall mean milk yield was 2780 kg (CV = 0·31) with mean lactation length of 281 days. Maximum production occurred in the fifth lactation (104 or 105 months of age at calving) with a yield of 1·3 times that of the first lactation. Repeatability estimated by intraclass correlation was 0·40 (s.e. 0·03). Heritability estimated from paternal half-sib correlation was 0·16 (s.e. 0·06). Overall results were very similar to those obtained from research with European breeds in temperate areas.
The effect of level of pre-mating nutrition on ovulation rate in Scottish Blackface ewes in different body conditions at mating
Authors: Gunn R. G. , Doney J. M. , Smith W. F. 
Published: September 2010

ABSTRACTIn two experiments over 2 years, 181 Scottish Blackface ewes were differentially group-fed indoors to achieve moderately-good (score 2·5), moderate (score 2) or poor (score 1·5) body condition. Over 5 weeks prior to mating, ewes in moderately-good condition were either maintained or brought down to moderate condition by restricted feeding and ewes in moderate and poor condition were raised, respectively, to moderately-good and moderate condition by a high level of feeding. After mating, ewes were maintained in condition until slaughtered for a count of corpora lutea relating to first service. Ovulation rate was positively and significantly related to the level of pre-mating food intake at the moderate level of condition but not significantly so at the moderately-good level. It is postulated that ewes of this breed are more sensitive to the level of pre-mating food intake when in moderate condition at mating than they are when condition has risen to a moderately-good level.
Further studies on the heat production and effective lower critical temperature of early-weaned pigs under commercial conditions of feeding and management
Authors: McCracken K. J. , Gray R. 
Published: September 2010

ABSTRACTIn two separate experiments pigs were weaned at 14 or 28 days and heat production was determined in an open-circuit respiration chamber at temperatures above and below the lower critical temperature (Tcl) at intervals during the post-weaning period.With 14-day weaned pigs the mean 24 h heat production above Tc1 averaged 267, 328, 474 and 554 kJ/h per m2 at 3, 9, 15 and 21 days post weaning respectively. The mean thermal conductance (H/AT, kJ/h per m2 per °ΔT, where H is total heat production, m2 is the surface area calculated as 0·097 M kg0·633 and °Δ is the difference between rectal temperature, taken at 39°, and air temperature) below TC1 was calculated as 20·5, 20·1, 23·1 and 24·2 at 17, 23, 29 and 35 days of age respectively and the corresponding values for Tc1 were 25·9, 23·0, 18·4 and 16·0°C.With 28-day weaned pigs the mean 24 h heat production above Tc1 averaged 280, 361 and 445 kJ/h per m2 at 3, 9 and 15 days post weaning. The calculated values for H/ΔT were 19·7, 20·8 and 21·6 and the corresponding values of Tcl were 24·8, 21·7, and 18·8°C at 31, 37 and 43 days of age respectively.The results are discussed in relation to previous studies on 10-day and 28-day weaned pigs and in relation to the practical implications for pigs weaned into controlled-environment accommodation.
A note on the effects of pre-slaughter housing, diet and sex on responses to post-mortem electrical stimulation in cattle
Authors: Jedlička J. , Mojto J. , Foltys V. , Lichtner J. , Szakáczová D. , Páleník Š. 
Published: September 2010

ABSTRACTEffects of the period of pre-slaughter lairage and diet on responses to post-mortem electrical stimulation (ES) were observed in 113 bulls and 18 cows. The efficiency of ES was assessed by the rate of the decrease of muscle pH. Stimulation was made at 80 V for 45 s. ES significantly decreased pH values at 1 h after slaughter. The effect was greater for animals on a normal diet than for those on a reduced diet. ES was also more effective for animals killed within 2 h after transportation to the meat processing plant than for animals slaughtered 24 h after transportation. There were no significant differences in the effect of ES between sexes. The basic requirement for effective ES is a good condition of animals at slaughter.
Lactation performance of goats and growth rates of kids under different milking and rearing methods in Kenya
Authors: Ruvuna F. , Cartwright T. C. , Blackburn H. , Okeyo M. , Chema S. 
Published: September 2010

AbstractTwo experiments were conducted to test different milking procedures for dual-purpose goats that would be suitable for smallholder farmers. In experiment 1, 105 East African and Galla does that kidded to singles were randomly assigned to three treatments: (a) milking in absence of kid and kid sucking residual; (b) milking in presence of kid and kid sucking residual; and (c) milking once a week and kid sucking all milk 6 days of the week. In experiment 2, 45 Galla does that kidded to singles were randomly assigned to three treatments: (a) weigh-suckle-weigh; (b) milking half udder while kid sucking other half and (c) kid sucking all milk in the evening and milking mornings. Measurements of milk yield, milk sucked and weights of kids were taken for 12 weeks of lactation.Results were analysed using least-squares techniques for unequal subclass numbers. Milking in the presence of kids increased does' milk yield. This increase was attributed to the stimulation of milk let-down by the presence of kids. Although this method potentially provided most milk for dairy use, less residual milk was left to sustain growth of kids. Estimates of total milk yield by milking once a week underestimated milk yield potential of the East African and Galla breeds. Results indicated an appropriate method for estimating milk potential should combine both milked and sucked milk measurements. Restricting milk available to the kids reduced their growth rates and thus indirectly affected their maturing rates. No milking procedure proved to be superior all-around for the smallholder for milking goats. To resolve this dilemma, use of an optimizing technique including socio-economic weighting of milk for family use relative to milk for kids was proposed.
Road transport of pigs over a long distance: some aspects of behaviour, temperature and humidity during transport and some effects of the last two factors
Authors: Lambooy E. 
Published: September 2010

AbstractDuring the transportation of pigs over a long distance, the environment in individual compartments may be related to the climate outside the trailer and may affect the animals. During three international and six experimental transport trials over long distances the relationships between outside and inside temperature and humidity were determined. During the experimental journey pig behaviour was studied and the effect of the environment on meat quality was also measured subsequently.During the three international journeys the correlation coefficients between the outside and inside temperatures of the trailer were 0·88, 0·81 and 0·54, respectively, whereas there were low positive or negative correlations for relative humidity. The live-weight losses were 60, 80 and 60 g/kg, respectively, and the mortality averaged 0·3%.The live-weight loss averaged 40 (s.d. 6) g/kg during each 25-h experimental journey, while the mortality was 1·4%. During the course of the journey, a majority of pigs was sitting or lying. During the night and at stops in transit most pigs were lying down.The correlation coefficients between the outside and inside temperature averaged 0·94 in the artificially, and 0·95 in the naturally, ventilated compartments, while the coefficients for the humidity were 0·66 and 0·77, respectively. Pigs ventilated artificially showed a lower rigor mortis and lower temperatures of the m. longissimus dorsi (LD) and m. semimembranosus (SM) muscles post mortem compared with those ventilated naturally.A higher temperature in the compartment was related to a lower temperature in the LD and SM muscles at 24 h (P ≤ 0·05) and a higher pH of the SM muscle in the carcass (P ≤ 0·05). However this was also affected by the location of the compartment on the vehicle. A major temperature fluctuation was related to a lower rigor value (P ≤ 0·05).I t may be concluded from these experiments that the environmental conditions during transport over a long distance may change markedly. High temperatures in the compartment may increase stress, while correct artificial ventilation may decrease stress.
Index selection for improved growth and carcass characteristics in a population of Large White pigs
Authors: Ellis M. , Chadwick J. P. , Smith W. C. , Laird R. 
Published: September 2010

AbstractAn experiment was carried out over 11 years to investigate selection for economy of production and carcass lean content under ad libitum feeding in Large White pigs. Two lines, a selection (S) and a control (C) line, were involved in the study. The S line comprised 80 females and 10 males and was based at two centres. Boars were performance tested centrally at one of the centres and gilts were on-farm tested. Testing was carried out in groups of two or three full-sibs over the live-weight range 27 o t 87 kg. Selection was based on an index (I) incorporating individual daily live-weight gain (DLWG) and ultrasonically measured backfat thickness (USBF) and a group food conversion ratio (FCR) and generations were overlapping. The C line (32 females and 16 males) was maintained at one centre and males were performance tested alongside S boars to monitor genetic progress. Cumulative realized selection differentials over years 1 to 10 were equivalent to 5·5, 51, 7·0 and 9·4 phenotypic standard deviations for DLWG, USBF, FCR and I respectively and generation intervals averaged 17·0 months. There was little genetic change in DLWG, however, USBF, FCR and I showed substantial improvements with cumulative responses in year 11 of —12·3 mm, —0·22 kg/kg and +45·2 points respectively. The reduction in USBF occurred in the first half of the study with no further improvements being achieved after year 6. This study illustrates the effectiveness of index selection for a limited number of economically important traits but highlights limitations to this approach.
The effect of protein content of the supplement for dairy cows with accessad libitumto high digestibility, wilted grass silage
Authors: Gordon F. J. 
Published: September 2010

ABSTRACTGrass silage with a dry-matter (DM) content of 253 g/kg and containing 142 g crude protein and 670 g digestible organic matter/kg DM was offeredad libitumto 56 first- and second-lactation British Friesian cows during the first 75 days post-calving. In addition the animals received supplementary concentrates containing either 95 (T1), 137 (T2), 174 (T3) or 209 (T4) g crude protein per kg fresh weight, with extracted soya bean meal being used as the protein source. All concentrates were offered at equal levels across treatments, the amounts being 8 kg for first- and 10 kg per day for second-lactation animals. The silage DM intakes recorded over the period were 514, 524, 548 and 545 ± 19·9 kg and milk outputs were 1349, 1451, 1533 and 1628 ±40·2 kg for treatments Tl to T4 respectively. The rate of live-weight change and the milk fat, solids-not-fat, protein, lactose and ash contents of the milk were not affected significantly by any of the treatments. Diet digestibilities were determined using three animals per treatment. The digestibility coefficients were for DM 0·738, 0·746, 0·776 and 0·772 ± 0·0088 and nitrogen 0·597, 0·641, 0·707 and 0·727 ±0·0126 for treatments T1 to T4 respectively.
Analysis of some factors which affect the productivity of beef cows and of their calves in a marginal rainfall area of Rhodesia 3. Factors affecting calf birth weight, growth to 240 days and use of concentrates by cows and their calves
Authors: Richardson F. D. , Oliver J. , Clarke G. P. Y. 
Published: September 2010

ABSTRACTThe birth weight and growth rate of sucking calves reared by three groups of cows grazing on veld and receiving different amounts of concentrates during winter and the first 8 weeks of lactation were studied over four successive calving seasons. Calves were weaned at either 150 or 240 days. The efficiency of use of concentrates for weaned calf production was calculated.Calves from cows given most concentrates were heavier (P<0·01) than othei calves at birth, 150 days and 240 days. Milk consumption during the first 98 days of life accounted for most of the variation in pre-weaning growth. Time of weaning had little effect (P<0·05) on birth weight of the next year's calf and although cows in the early- weaning groups produced calves which were the heaviest at 150 days (P>0·05) these calves weighed less than other calves at 240 days (P<0·001). Simple and multiple regression analyses were used to show that birth weight was affected significantly by cow-weight change during winter and these differences were in part independent of treatment and year. Calf birth weight increased as age of dam increased but this was due to increase in weight of cow with age. Within classes, calf birth weight had a significant and positive effect on weight gain after accounting for milk consumption and this was shown to be an effect of sex. Cows given concentrates produced more weight of 240-days-old weaned calf per year than those given none (P<0·01), and late weaning led to the production of more weaned calf per annum than early weaning (P< 0·001) even when allowance was made for differences in concentrate consumption.
Analysis of some factors which affect the productivity of beef cows and of their calves in a marginal rainfall area of Rhodesia. 4. The growth and efficiency of live-weight gain of weaned and sucking calves at different ages
Authors: Richardson F. D. 
Published: September 2010

ABSTRACTThe growth and efficiency of live-weight gain of 36 calves confined in pens was studied between 30 and 210 days of age. They were weaned individually at 30, 90 or 150 days old and offered one of three solid foods which contained 200, 300 or 400 g milled roughage/kg both before and after weaning. From 30 to 90 days and from 90 to 150 days weaned calves consumed more (P<0·001) solid food than sucking calves. During both these periods sucking calves consumed more (P< 0·001 and P<0·05 during the first and second periods respectively) metabolizable energy (ME), gained more (P<0·01) body weight and also gained more body weight/MJ ME consumed than weaned calves. Composition of solid food had little effect on calf performance.The combined efficiency (kg calf weight gain/MJ ME consumed by cow and calf unit) was higher (P<0·001) for suckling cows and calves than for weaned cows and calves between 30 and 90 days. Between 90 and 150 days, weaning had no effect on combined efficiency.Eight similar calves which were reared by their dams on veld until 210 days of age were heavier at 90 (P< 0·001) and 150 (P<0·05) days than penned calves which had been given concentrates ad libitum since weaning at 30 days. The body weights of these two groups were similar at 210 days.