bluuebunny/crossref_metadata_2025_split huggingface dataset:
Derivation of economic weights from profit equations
Authors: Brascamp E. W. , Smith C. , Guy D. R. 
Published: September 2010

ABSTRACTThe economic weights derived from profit equations depend on the base used for the evaluation. Thus different relative economic weights are obtained per unit of investment, per breeding female, per individual or per unit of product. This has led to uncertainty and confusion about appropriate economic weights in livestock improvement, and to apparent differences in interests between the investor, the farmer and the consumer. It is shown here that if the profit equation has a zero outcome, or the profit equation is transformed by setting its outcome to zero by considering profit as a cost of production (so called ‘normal profit’ in economics), then the relative economic weights are the same for all bases of evaluation. It is argued that this is the appropriate basis to determine economic weights.
The tolerance of grazing desert ewes and their lambs to prolonged intake of natural saline waters
Authors: Mittal J. P. , Ghosh P. K. 
Published: September 2010

ABSTRACTThe effect of prolonged intake of saline well waters on the productive performance of 56 mature ewes and their lambs of the Magra and Marwari breed of the Rajasthan desert was studied for a period of 44 months. The sheep were maintained at pasture and given drinking water containing 0·3, 2·0 and 3·5 g/1 of total soluble salts. Body-weight changes during pregnancy and lactation, milk yields, greasy-fleece yields of the ewes, lamb birth weights and subsequent body-weight gains, up to weaning and post weaning, and greasy-fleece yield and pre-weaning and post-weaning survival rates of the lambs remained unaffected by the salinity levels in the waters tested.
The effects of reducing the remating interval after parturition on the reproductive performance of the commercial doe rabbit
Authors: Partridge G. G. , Allan S. J. , Findlay M. , Corrigall W. 
Published: September 2010

ABSTRACTFour groups of does (16 per group) were remated either 1, 7, 14 or 21 days after parturition over a 1-year production cycle. Doe mortality rate was independent of treatment and overall was 0·27. The remating interval after parturition had no effect on conception rate, which was high on all treatments (0·86 to 0·93). The high overall conception rate resulted in more litters being born as the parturition to remating interval decreased. Expressed on a common 365-day experimental period the number of litters per doe was 8·9, 8·5, 7·8 and 6·7 (average s.e. of difference 0·33) for treatments 1, 7, 14 and 21 respectively. Litter size was not significantly affected by treatment and consequently the number of pups born per doe per year increased as remating interval decreased: 75·0, 73·4, 67·4 and 591 respectively. Pup mortality rate at birth and subsequently was high (0·42) on all treatments and the number of pups weaned per doe per year for treatments 1, 7, 14 and 21 was 48·3, 43·5, 40·0 and 33·3 respectively. Pup birth weight, 21-day litter weight and weaning (25-day) weight were all unaffected by treatment, as was doe body-weight change.
A note on lactation curves of crossbred cows
Authors: Jenkins T. G. , Ferrell C. L. 
Published: September 2010

ABSTRACTMilk production data were collected on 8- and 9-year-old Angus × Hereford or Hereford × Angus; Charolais × Angus or Hereford; Jersey × Angus or Hereford; and Simmental × Angus or Hereford cows at days 14, 28, 56, 84, 112, 140, 168 and 196 after parturition. During the study, cows were given diets differing in quantity of brome grass (Bromus inermis) haylage. Lactation curves were estimated by the empirical equation Y(n) = n/aekn. Differences were observed among the breed crosses in 25-week lactation yield and time of peak lactation.
Factors influencing the work done by draught oxen: a study in the eastern hills of Nepal
Authors: Anne Pearson R. , Lawrence P. R. , Ghimire C. 
Published: September 2010

ABSTRACTThe work done, distance travelled and body temperature of five teams of oxen ploughing land for winter crops was measured continuously over a 5-h working day. On terraces in East Nepal the cattle worked at slow speeds (about 0·3 m/s). Daily work output was variable and depended on ground and soil conditions and on the man working the team. Estimated daily energy expenditure on working days in October and November was 1·25 to 1·46 × maintenance. Differences between teams were small. No noticeable change in performance occurred over the 5-h work, with the exception of one team which usually worked erratically over the last 2 h. Only one animal showed signs of heat stress during work, when its body temperature increased by 1·8 to 2°C, otherwise body temperature varied little (< 1°C) during work.
Factors influencing the welfare and carcass and meat quality of pigs 1. The effects of stocking density in transport and the use of electric goads
Authors: Guise H. J. , Penny R. H. C. 
Published: September 2010

ABSTRACTThis experiment was designed to study the effects of stocking density in transit and the use of electric goads on pig welfare and subsequent meat quality. Sixty-four pens, totalling 1400 commercial crossbred hybrid pigs, were transported from a farm to a large commercial abattoir at either high (0·3 m2per pig) or low (>0·4 m2per pig) stocking densities. The lorry drivers loaded and unloaded the pens of pigs at either end of their journey with, or without, an electric goad. Similarly, lairage men moved groups of pigs from their lairage pens to the stunning and slaughter area with, or without, goads. Consequently, eight possible treatment combinations arose from this 2 × 2 × 2 factorial experiment. About 20 h after slaughter, the fibre optic probe (FOP) value of thelongissimus dorsimuscle was recorded and carcasses were scored for the extent of skin blemish. Pigs in high stocking density groups (HSD) had lower FOP values than those on low stocking density groups (LSD) (P< 0·05) and more severe skin blemish (P< 0·001). The effect of goading in transport or in the lairage, had no significant effect on the FOP values. However, the skin blemish data showed a significant interaction between the use of goads during transport and the stocking density treatment (P< 0·05). This interaction implied that the use of goads when loading pigs at a HSD was associated with a reduction in skin blemish. Conversely, the lowest skin blemish frequency was observed in the LSD treatment group handled without the aid of goads. Pigs in the HSD groups were visibly more skin damaged and exhibited evidence of rectal prolapse which was absent in pigs transported at LSD. Lower stocking densities are to be recommended as carcass, meat quality and pig welfare are probably improved. The use of goads is associated with a higher degree of carcass damage unless pigs are to be densely packed during transport.
Feeding and management of pregnant sows on pasture
Authors: Eyles Dudley E. 
Published: September 2010

1. Wessex Saddleback sows were fed 4 lb. or 2 lb. of a balanced meal per head per day during the first 13 weeks after mating with a Large White boar. All sows received 6 lb. of meal for the last 3 weeks of pregnancy, and approximately 14 lb. (4 lb. plus 1 lb. for each piglet) during lactation. From mating to weaning half the sows on each feeding treatment had access to small soil pens, and the other half to range grazing of lucerne or grass/clover swards.2. During the first 3 months of gestation sows on soil receiving 2 lb. of meal gained 20 lb. while those on grazing gained 40 lb., equal to the gain of sows fed 4 lb. of meal.3. Approximately 10·5 piglets were born per sow under all treatments. Piglet mortality was highest with sows which had been fed 4 lb. of meal during pregnancy and were confined in small soil pens, because this treatment produced the greatest number of over-fat sows. Mean piglet weight at 3 weeks (≏ 12 lb.) and 8 weeks (≏ 39 lb.) and total creep-fed meal consumption per piglet (≏ 30 lb.) were similar for all treatments.4. In a preliminary trial 3½ lb. of dried grass plus ½ lb. of meal per head per day was fed to gilts during the second and third months of pregnancy without adversely affecting farrowing results.5. From these experiments and the published work it is suggested:—(a) Pasture alone would probably have been sufficient during the second and third months of pregnancy of the sows used in these trials.(b) Feeding standards for pregnant sows of 250-350 lb. live-weight may be too generous, and produce ‘fat not fit’ sows at farrowing.(c) In practice the reduction of meal feeding and the greater dependence on grazing should be applied individually to each sow according to her condition and response.
Blood group studies on cattle of Red Polish breed
Authors: Neimann-Sørensen A. , Spryszak A. 
Published: September 2010

Blood samples from 262 Polish Red Cattle, 9 Danish Red Cattle and 123 cattle produced by crossing were examined for the presence of 45 erythrocyte antigenic factors.The frequencies of most of the factors are given and estimates are made of the appropriate gene frequencies within the Polish Red breed as a whole.Segregation of 42 B alleles was observed of which 9 have not previously been reported. The H′ factor hitherto recorded as marking an independent system is assigned to the SU system on genetical grounds and renamed S2.It is concluded from the blood group data that the Polish Red breed has signs of a genetic relationship with Holstein-Friesian, Brown Swiss and Guernsey breeds but the relationship with the Danish Red breed is closer. The existence of the new alleles distinguish the Polish Red breed of cattle from all others investigated.
The size of dairy heifers
Authors: Hodges John , O'Connor L. K. , Clark W. M. 
Published: September 2010

1. A field investigation to estimate the mean weight and chest girth of unserved Friesian, Ayrshire and Dairy Shorthorn heifers of between 3 and 24 months of age was carried out.2. Data from 1,620 Friesians, 725 Ayrshires and 455 Dairy Shorthorns in the North of England were obtained, with a mobile weighbridge and a. spring-loaded steel tape in the winter 1958–59.3. It was found that on average the Friesians were heavier and had a greater chest girth than the Ayrshires and Dairy Shorthorns, which did not differ significantly.4. These heifers were apparently reared on planes of nutrition which, judged by conventional feeding standards, may be described as ‘low’.5. After eliminating the linear effect of age by covariance analysis, highly significant differences between herds and between sires in weight and chest girth were found.6. The investigation demonstrated the feasibility and value of collecting field data on body size.
The effect of variations in the energy and protein status of the diet upon productive efficiency in the pig
Authors: Costain R. A. , Morgan J. T. 
Published: September 2010

A feeding trial is described in which 32 individually-fed Large White pigs were used to investigate the effects of variations in the protein and energy status of the diet on growth, efficiency of food utilisation and carcass characteristics. The salient features of the finding were:1. Over the weight interval 50–100 lb., it appeared that 1·0% was a more appropriate level of dietary lysine than one of the order of 0·75%; the former figure corresponded to a level of 5·8% of dietary protein.2. In the ‘finishing phase’ of growth from 100–200 lb. the pig clearly tolerates wider energy : protein ratios than is the case in earlier life, with advantageous results in terms of growth performance but deleterious effects on carcass suitability.3. An increase in dietary energy status in the ‘finishing phase’ yields growth responses only if protein level is appropriately adjusted.4. It is suggested that Large White pigs require a level of 0·5–0·6% of dietary lysine in the ‘finishing’ period.
Specialised sire and dam lines. I. Economic evaluation of crossbreds
Authors: Moav Rom 
Published: September 2010

When commercial livestock are crossbreds, profit for the total operation including cost of production of the breeding stocks, is a function of the performance of both the crossbred offspring and their parents.Since the performance level of the offspring is determined by its parents, it means that the parents contribute to profit determination in two ways. Reproduction cost is determined directly by the parents, that is through their own phenotypes, while productive efficiency (food conversion, growth rate, etc.) and quality are determined by the parents indirectly through the genetic determination of their offspring.In most classes of livestock the number of males in the breeding herds, relative to that of the females, is very small. Consequently, variation in reproductive capacity of the male line contributes only little to the determination of reproductive costs, and this item can be ignored. As a result, the contributions of the parental lines to profit are unequal and of different kinds. Exploitation of this difference may produce ‘profit heterosis’ even when the component traits are genetically additive.When profit is a non-linear function of one or more component traits another deviation of profit from the arithmetic mean of the parents is created. Unlike the previous one, this heterosis deviation is scale dependent.Profit was presented graphically, as profit contours, on the two dimensional plane created by the variables productivity and reproductivity. This was found to be a helpful aid to an understanding of the underlying relationships.
Effects of reduction of litter size on subsequent growth and reproductive performance in mice
Authors: Machin David , Page Sheila 
Published: September 2010

SUMMARYLitters that contained at least 13 mice were reduced at birth to 12, 8, or 4; and any natural litters of these sizes were also kept. The growth of these mice and their subsequent reproductive performance when mated at 6,10 and 14 weeks of age were recorded. All their offspring were weighed at weaning (4 weeks); some were weighed also at 12 days and 6 weeks of age.The amount of milk supplied was not fully adjusted to the size of the litters. This had lasting effects so that, even at the oldest age for mating, the mice from the small litters were noticeably the heaviest. Litter size effects extended to significant differences in fertility (numbers born) and less obviously to the numbers weaned. The mice that were mated at 14 weeks were the most fertile. There was little to distinguish the mice from natural and reduced litters of the same size.Small differences in weights of the offspring at 12 days, 4 weeks and 6 weeks of age bore no consistent relation to these factors.
A Comparison of some suggested measures of persistency of milk yield in dairy cows
Authors: Madsen Ove 
Published: September 2010

SummaryFive measures of persistency of milk yield were compared by means of apparent heritabilities and repeatabilities using 598 first lactation records from the Danish progeny testing stations and 354 records of all parities from Red Danish cows at a state experimental farm. Unbiased estimates of heritabilities could not be obtained because of common environmental effects. Results indicate that measures of persistency giving equal weight to single milk records are superior to measures giving different weight to single records.Correlations between persistency, expressed as the absolute decrease of yield, and maximum daily yield were —0·46 to —0·52 (phenotypic) and —0·22 (genetic). Correlations between persistency and 305-day yield were —0·06 to —0·10 (phenotypic) and 0·02 (genetic).Correlations between persistency, expressed as the decrease of yield relative to level of yield in early lactation, and maximum daily yield were —0·06 to —0·13 (phenotypic) and 0·17 to 0·42 (genetic). Correlations between the measure of persistency and 305-day yield were 0·12 to 0·45 (phenotypic) and 0·45 to 0·69 (genetic).
The response of lactating sows and their litters to different dietary energy allowances. 2. Weight changes and carcass composition of sows
Authors: O'Grady J. F. , Elsley F. W. H. , MacPherson R. M. , McDonald I. 
Published: September 2010

SummaryThe live-weight changes of 48 sows were recorded over three reproductive cycles. All sows were given standard amounts of feed in gestation and one of four energy allowances during lactation. The daily intakes of digestible energy during lactation ranged from 12·2 to 182·2 Meal in the first, 122·9 to 192·6 Meal in the second and 132·2 to 202·2 Meal in the third lactation. Weight change in lactation responded to energy intake; sows on the lowest energy intake lost weight whilst those on the highest intake gained. At weaning of their third litters, sows on the highest energy allowance weighed 44 kg more than those on the lowest level and this was equivalent to a carcass difference of 372·3 kg at slaughter.All the sows were slaughtered after the third litters had been weaned and the carcasses were dissected into lean, subcutaneous fat+skin, and bone. Sows from all treatments had less subcutaneous fat+skin and more muscle and bone than non-pregnant gilts killed at a mean weight of 129 kg, a weight equivalent to that of the experimental animals at their first mating.The reduction in fat reserves was linearly correlated with dietary energy intake of the sows. Sows receiving the lowest energy intake in lactation possessed fat reserves which were estimated to be only 25% as great as in gilts comparable to those used to initiate the experiment. This reduction in body reserves has implications with regard to the long-term effects of feeding lactating sows low intakes of energy during 6-week lactations.
Theoretical aspects of a flexible model to stimulate protein and lipid growth in pigs
Authors: Whittemore C. T. , Fawcett R. H. 
Published: September 2010

SummaryA model designed to simulate growth in pigs has been developed to include the following aspects of protein and energy use.1. It is proposed that the ratio of protein accretion to protein synthesis is a function of protein mass. Synthesis rate influences the efficiency of protein use, the energy cost of protein accretion and the energy cost of maintenance. A calculated energy cost for protein synthesis of 7·3 MJ ME/kg is suggested; the calculated energy yield from deaminated protein is 11·5 MJ ME/kg.2. Urinary losses of nitrogen are derived from estimates of protein quality by essential amino acid index, endogenous losses and the rate of protein accretion.3. A minimum fat to protein ratio in the gain of growing pigs of 1: 1 is assumed.4. An estimate of critical temperature which is dependent upon live weight and heat output is used to calculate energy expenditure for cold thermogenesis.
Genetic and environmental factors influencing litter size, sex ratio and gestation length in the pig
Authors: Kennedy B. W. , Moxley J. E. 
Published: September 2010

ABSTRACTData from 675 litters were used to study the effects of type of service, number of services, parity, year, season, breed of sire, sire, type of dam (purebred or crossbred), breed of dam, dam, breed of sire × type of dam and breed of sire × breed of dam on litter size (live births), number of males, number of females, sex ratio (percentage of males) and length of gestation. Yorkshire, Landrace and Lacombe breeds and their crosses were represented. Artificial insemination significantly reduced litter size and the number of females and increased sex ratio. Parity had a significant effect on all traits except sex ratio. Lacombe-sired litters were approximately one-half pig smaller than Yorkshire- and Landrace-sired litters. Landrace-sired litters had gestations of one-third day shorter than Yorkshires. On average, crossbred dams farrowed 0·65 more pigs per litter than pure-bred dams. Litters from Yorkshire dams, however, were more than one pig larger than Landrace and Lacombes, and did not differ significantly from crossbred dams. Gestation length of Lacombe sows was 1·34 days shorter than Yorkshires. Repeatabilities of litter size, number of males, number of females, sex ratio and gestation length were 0·15, 0·08, 0·06, 0·05 and 0·32 respectively.
Chaffed or ground straw and lucerne in the diet of the early-weaned calf
Authors: Leibholz Jane , Russell C. L. 
Published: September 2010

ABSTRACTAn experiment was conducted with 72 male British Friesian calves between 5 and 11 weeks of age. The major treatments were the inclusion of 0, 20 or 40% wheat straw or 20, 40 or 60% lucerne in a complete pelleted diet. The roughage was either ground or chaffed. A methane inhibitor was included in the diets given to 36 of the calves. The weight gains of the calves were greater with diets containing lucerne than with those containing wheat straw. Grinding increased the intake of wheat straw but depressed intake of lucerne. The apparent digestibility of dry matter and acid detergent fibre, which was greater for the diets containing lucerne than for the diets containing wheat straw, was reduced by grinding both roughages.Inclusion of the methane inhibitor in the diets increased the feed intakes and weight gains of the calves given the all-concentrate diet and the diets containing wheat straw, but not those given the diets containing lucerne.
A note on the effects of dexamethasone-induced parturition on ewe behaviour and lamb survival in prolific Booroola Merino ewes
Authors: Owens J. L. , Bindon B. M. , Edey T. N. , Piper L. R. 
Published: September 2010

AbstractNormal and dexamethasone-induced parturition were compared in Merino and prolific Booroola Merinos carrying crossbred foetuses. Behavioural observations were recorded for 42 single-, 27 twin- and 10 triplet-bearing ewes. After treatment on day 144 of gestation, ewes injected with dexamethasone lambed 41 h earlier than ewes injected with phosphate buffer. On the phosphate-buffer treatment, Booroola Merino ewes lambed 22 h earlier than Merino ewes. Twin- and triplet-bearing ewes which were induced to lamb had a significantly longer duration of labour than ewes bearing singles which were induced to lamb, and ewes, regardless of litter size, which lambed naturally. Induction of parturition had no significant effect on the lambs' behaviour subsequently. Lamb survival was not influenced by dexamethasone treatment but was significantly influenced by lamb birth weight, which declined as litter size increased.
Faecal output and estimated voluntary dry-matter intake of grazing beef cows, relative to their live weight and to the digestibility of the pasture
Authors: Bruckental I. , Lehrer A. R. , Weitz M. , Bernard J. , Kennit Hanna , Neumark H. 
Published: September 2010

AbstractTwo experiments were carried out with 12 non-pregnant, non-lactating beef cows (Simmental x Hereford cross), six in each experiment. In experiment 1, the cows were grazing stubble pasture and each cow was hand fed 750 g/day soya-bean meal. In experiment 2, the cows were grazing green pasture at the pre-blossom stage. Paraffin-coated magnesium ferrite (MF) was used as an external marker. A capsule containing 5 g marker was administered to each cow twice daily at about 08.00 and 14.00 h. At the same time the cows were also weighed and faecal grab samples (GS) were taken. Each experimental period lasted 18 days: a 10-day period for attaining steady state of the marker, followed by an 8-day period during which faecal GS were taken.Average live weight (LW, kg) and daily faecal output (DFO, kg dry matter (DM) per day) were, respectively 364·2 and 3·39 for cows in experiment 1, and 484·4 and 4·62 in experiment 2. DFO (g): LW (kg) ratios were 9·31: 1 and 9·53: 1 in experiments 1 and 2, respectively.In-vitro digestibilities were used for calculating the voluntary intake (kg DM per day), which was found to be 6·8 and 13·6 for cows grazing stubble and pre-blossom pastures, respectively. The relationships between LW of grazing cattle and their DFO and voluntary food intake are discussed.