bluuebunny/crossref_metadata_2025 huggingface dataset:
The management of calves on an early-weaning system: the relationship of voluntary water intake to dry feed intake and live-weight gain to 5 weeks
Authors: Thickett W. S. , Cuthbert N. H. , Brigstocke T. D. A. , Lindeman M. A. , Wilson P. N.
Published: September 2010

A trial compared the voluntary water intake of 72 purchased British Friesian bull calves fed at different nutrient intake levels by varying the type and strength of the milk replacer given to 5 weeks of age. There was no control group without water on offer. Water was offered from the 1st day the animals entered the unit. All calves received 4 1/day of either cows' milk (12 calves), milk replacer with 100 g fat per kg (24 calves), milk replacer with 170 g fat per kg (24 calves) or milk replacer with 200 g fat per kg (12 calves). Standard early-weaning pellets containing 190 g crude protein per kg and hay ad libitum were on offer from the 2nd day on the unit. Results indicated that voluntary intakes of water were highest with calves fed on cows' milk and lowest on the milk replacer with 100 g fat per kg given at the lowest mixing strength, although differences were only significant in week 5 (P ≤ 0·05). By covariance analysis, the effects of water intakes on live-weight gain and on pellet intake were examined. The regression coefficient of live-weight gain (weeks 0 to 5) (kg) on water intake (weeks 1 to 5) (1) was b= 0·056 (s.e. 0·021, P ≤ 0·01). The regression coefficient of pellet intake (weeks 0 to 5) (kg) on water consumption was: b= 0·082 (s.e. 0·031, P ≤ 0·01). There was thus a significant correlation of both live-weight gain and pellet intake with water intake. For each extra litre of water consumed per day, there was an extra pellet intake of 0·082 kg and an increase in live-weight gain of 0·056 kg. There was a significant difference in total water intake according to the initial live weight of the calf.
An evaluation of feedblocks as a means of providing supplementary nutrients to ewes grazing upland/hill pastures
Authors: Ducker M. J. , Kendall P. T. , Hemingway R. G. , McClelland T. H.
Published: September 2010

A series of trials was conducted to measure the extent of individual variation in feedblock intake for ewes on upland/hill farms. From 15 flocks on nine farms 4284 ewes were selected with a range of environmental conditions and levels of performance. Ewes were given either Rumevite, Norbloc or Wintawell feedblocks containing chromic oxide. Faecal grab samples were taken per rectum from individual ewes and analysed for their chromium content to obtain estimates of feedblock consumption.

The results showed that provision of feedblocks does not ensure a uniform intake of supplementary nutrients by sheep in upland/hill situations. On average, 19% of the 2931 ewes sampled had not eaten the feedblock on offer. The proportion of ewes not consuming feedblock varied from flock to flock (0 to 67%). The coefficient of variation of faecal chromium concentrations varied between flocks (46 to 231%). The reasons for the large variation in intakes observed are discussed. Feedblock intake was significantly affected by the grazing area per ewe (P<0·01) and the age of ewes (P<0·05 to P< 0·001).
Effect of sex and birth status on the wool follicle population in unselected Corriedale sheep
Authors: Butler L. G.
Published: September 2010

The follicle population of 44 purebred 20-month-old Corriedale ewes and rams was examined for effects due to sex and birth status. Twin birth resulted in a lower ratio of secondary to primary follicles at 20 months of age in these medium follicle-density animals. This effect is similar to that reported for the high follicle-density Australian Merino. Similarly, the ewes had a lower ratio of secondary to primary follicles than the rams.
Amino acid requirements of growing pigs 2. Identification of the limiting amino acid(s) in a low-protein diet supplemented with lysine
Authors: Taylor A. J. , Cole D. J. A. , Lewis D.
Published: September 2010

A basal diet containing 120 g crude protein per kg and 9g lysine per kg, and previously shown to be limiting in one or more essential amino acids and/or non-essential nitrogen, was examined. It was fed either alone to growing female pigs from 25 kg to 55 kg live weight or in combination with four supplements of synthetic amino acids each containing three out of isoleucine, methionine, threonine and tryptophan. A control diet containing 140 g crude protein per kg and 9g lysine per kg was also included. Blood samples were collected at 40 kg live weight in order to examine the influence of dietary treatments on blood metabolites. Results for growth performance, carcass composition and blood urea indicated that threonine was the first limiting amino acid in the basal diet. Plasma free amino acids gave no clear trend. Growth performance and carcass composition were unaffected by supplementation of the diet with glycine indicating that the dietary supply of non-essential nitrogen was adequate.
A Bayesian estimation of the lactation curve of a dairy cow
Authors: Goodall E. A. , Sprevak D.
Published: September 2010

A recursive procedure for the estimation of the lactation curve of a dairy cow, which allows the inclusion of prior information on the curve and which takes account of the correlation between successive observations, is described. The method is based on the Kalman filter. It was found to give accurate estimates of the total milk yield at early stages of lactation.
Effects of different energy intakes before and after calving on food intake, performance and blood hormones and metabolites in dairy cows
Authors: Kunz P. L. , Blum J. W. , Hart I. C. , Bickel H. , Landis J.
Published: September 2010

An experiment with 25 dairy cows was performed to investigate the effects of different energy intakes on food intake, performance and blood hormone and metabolite levels during the last 70 days of pregnancy and the first 125 days after parturition. Compared with animals fedad libitumbefore parturition, cows fed only according to requirements during the same time showed no decrease of food intake at calving. Cows fed at a restricted level also showed a faster increase in food intake, a smaller energy deficiency at the onset of lactation and a smaller weight loss after parturition. Peak milk yield was also lower, but the peak was maintained for a longer period, and during the first 2 months of lactation these cows had higher concentrations of glucose and lactic acid, and lower concentrations of non-esterified fatty acids and ketone bodies in the blood. Weight losses, and decrease of milk production during the 1st weeks of lactation were higher in cows fed only 0·75 of requirements during the first 60 days of lactation than in animals whose energy intake was planned to cover energy requirements, and during the first 2 months of lactation levels of unesterified fatty acids, ketone bodies and urea were higher, whereas levels of insulin, thyroxine and triiodothyronine were lower. Endocrine and metabolic changes seen during early lactation suggested improved glucose homeostasis, diminished fat mobilization and ketogenesis in cows given reduced amounts of energy during the dry period compared to animals fedad libitum. To prevent the development of acetonaemia an adequate energy supply during the first part of lactation is, however, of greater importance.
Growth of Holstein Friesian females in the Venezuelan tropics
Authors: Vaccaro R. , Rivero S.
Published: September 2010

A study was made of the growth of Holstein Friesian females in an intensive production system in the Venezuelan tropics, using monthly weights from birth (no. = 922) up to 72 months of age (no. = 63). Birth weights were adjusted for age of dam, month and year of birth of heifer, whereas subsequent weights were adjusted for birth weight and month and year of birth. Despite lower weights at birth (mean = 35·9 kg), live weights were comparable to the Beltsville standard for the breed up to 12 months of age. However, at 24, 36, 48 and 72 months of age the weights observed only reached 0·84, 0·77, 0·75, 0·79 and 0·78, respectively, of the Beltsville standard. No effect was observed on birth weight of age of dam, month or year of birth, but birth weight affected subsequent weights (P < 0·001) and the effects of month and year of birth on live weight were significant at most ages. The poor quality of the forage consumed and stress due to high environmental temperatures and humidity appear to be the main reasons for the reduced growth rates. Von Bertalanffy's model gave a higher residual error than a polynomial model when fitted to the data, but resulted in a curve which agreed more closely with the conventional biological growth pattern.
The effects of halothane susceptibility on some economically important traits in pigs 1. Litter productivity
Authors: Carden A. E. , Hill W. G. , Webb A. J.
Published: September 2010

The effects of susceptibility to halothane anaesthesia on litter productivity were investigated by comparing susceptible and normal females in two sets of data. The first comprised 206 litters from the first five generations of Pietrain/Hampshire synthetic lines selected for and against halothane susceptibility. Susceptible and normal females were mated to boars of their own type. The second data set consisted of 93 litters from the same susceptible and normal females mated to normal boars. Compared with normal contemporaries, litter sizes of susceptible females were reduced by 1·16 (s.e. 0·40) piglets at birth, and 1-76 (s.e. 0·41) at weaning (ca. 1 weeks). Maximum likelihood estimates of the proportions of piglet deaths from birth to weaning as a trait of susceptiblev.normal dams were 0·32v.014 (P < 0·001). There were no significant differences in piglet weights or perinatal mortality, and no apparent influence of piglet genotype on any trait. The lower litter size of susceptible females at weaning appeared to result from reductions in both numbers born and survival to weaning. The study bears out previous reports of a reduction in litter productivity due to the halothane gene. However, the present differences could have arisen largely from random genetic differentiation between lines, or linkage disequilibrium in the synthetic foundation population.
A note on the effect of the F gene on wool production and live weight of Booroola × South Australian Merino rams
Authors: Ponzoni R. W. , Fleet M. R. , Walkley J. R. W. , Walker S. K.
Published: September 2010

The effect of the high fecundity Booroola Merino gene (F) on wool production and live weight of Booroola x South Australian Merino rams classified as being offspring of FF, F+ or ++ Booroola sires was investigated. The characters studied were: greasy fleece weight in lambs, hogget (approx. 15 months old) greasy fleece weight and the associated scouring yield, clean fleece weight, fibre diameter, staple length and wool style; birth weight and live weight gains from birth to weaning in September (3 months of age), from September to the following March, and from March to September. There were no significant differences among sire genotypes in the characters studied. The results suggest that the F gene had no undesirable pleiotropic effects on wool and live-weight traits.
The influence of pre-weaning nutrition on subsequent growth and development of bacon pigs
Authors: Duckworth J. E.
Published: September 2010

The growth and carcass data were determined for pigs reared on two creep rations to different weights, and subsequently fattened with and without an antibiotic.

Pigs weaned at a ‘standard’ weight of 43·8 lb. at 56 days of age grew more quickly over the range 120 to 210 lb. live-weight than pigs weighing 51·0 lb. at weaning. Both groups were fed according to a fixed scale related to live-weight. Heavy weaners growing slowly in the later stages had slightly thicker backfat measurements, indicating that they were at a more advanced stage of physiological development than the light weaners.

The presence of antibiotic in the fattening ration caused no significant difference in growth rate or carcass measurements, but there were significant interactions between weaning weight and presence or absence of antibiotic in the fattening ration for length of carcass, and between sex and presence or absence of antibiotic for the traits of age at 70 lb. live-weight, carcass length and depth of mid-backfat.

Weaning weight and rate of gain from 70 to 120 lb. live-weight were significantly and positively related to carcass length.

It is concluded that further studies of the growth curve of the pig are required to determine the scope and importance of compensatory growth, and the interaction of growth rates in the different phases of the pig's life and their relationships to carcass traits.
Sustained release of chromic oxide in the rumen of sheep from a CR2O3-paper pellet
Authors: Troelsen J. E.
Published: September 2010

1. Pellets of Cr2O3-paper were administered to sheep to reveal the excretion pattern of Cr2O3 in the faeces.

2. Two sheep fed on long hay and pelleted hay for each of two 28-day periods were given a Cr2O3-paper pellet daily at 9 00 hrs. during the 15th to the 24th day inclusive in each period.

3. Total faeces were collected at hourly intervals during the 15th to the 28th day. Dry weight and concentration of Cr2O3 of each fraction was determined.

4. A balance between input and output of Cr2O3 and a minimal standard J deviation of the concentration of Cr2O3 in the faeces between hourly collections was reached in 3 days with long hay and in 2 days when the hay was given as pellets.

5. The decline in the concentration of Cr2O3 in the faeces started the day after the administration of pellets was discontinued.

6. Grinding and pelleting of the hay resulted in a doubling of the standard deviations of the concentration of Cr2O3 in the hourly faeces collections during the period of input-output equilibrium.

7. A pattern of a diurnal cyclic trend was apparent in the concentration of Cr2O3 in the hourly faeces collections, but it varied between animals and between diets.

8. Pellets of Cr2O3-paper are suggested to facilitate the administration of Cr2O3 to ruminants.

9. The effect of sampling frequency and animal replication on estimation accuracy is discussed.
A note on blood groups and haemoglobin variants in Zebu cattle
Authors: Naik S. N. , Sukumaran P. K. , Sanghvi L. D.
Published: September 2010

Blood groups and haemoglobin (Hb) variants are well defined genetical characters in man and animals. In 1940 Irwin and his associates initiated the study of cattle blood groups in Wisconsin by following the immunization method and haemolytic technique. Now several laboratories all over the world are engaged in this type of study in cattle and other species of animals. There are about 80–90 antigenic factors known comprising eleven blood group systems in cattle (Stormont, 1962).
The effect of age and live-weight on the feed intake of grazing wether sheep
Authors: Hadjipieris G. , Jones G. W. , Holmes W.
Published: September 2010

1. Estimates of the voluntary feed intake of three age groups of wether sheep on ryegrass and white clover pasture from July to October, 1962, were made by total collection of faeces and the use of local faecal nitrogen-digestibility regressions.

2. Average faecal output and intake of digestible organic matter (DOM) increased with age of the sheep. However, relative to body weight (W) or to W073, the aged sheep (5 years old), which did not change much in weight over the period, consumed only about two-thirds of the DOM consumed by the younger (sixteen- and four-month-old) growing sheep.

3. For the growing sheep intake was directly related to weight. Intake was calculated to be 24 W (kg.)–28 ±108 g. DOM per day.

4. The results are discussed in relation to the errors in estimation of digestibility. Comparison of the intake estimates with other published data suggests there was a high apparent maintenance requirement. The voluntary feed intakes observed, when expressed as g. dry matter per kg. W0–73, were somewhat higher for young sheep but lower for aged sheep than estimates of previous authors.
A note on the influence of parity of dam on daughter heifer performance and on selection of replacements in dairy cattle
Authors: Robertson K. J.
Published: September 2010

One of the causes of culling dairy cows is low milk yield and to the extent that this has any genetic basis one might expect the daughters of old cows to outyield their contemporaries from younger and hence less selected mothers. This is quite apart from any confounding effects resulting from the non-genetic influences of dams' parity. The rate of genetic improvement derived from the culling process will be modified within a population by the extent to which farmers choose to retain the progeny of older rather than younger cows. Milk yields for recorded cows in Scotland, available to the Livestock Records Bureau, have been used to obtain some information on these points.
Some responses of hill ewes and lambs to artificial shelter
Authors: Miller G. R.
Published: September 2010

1. Experiments were done to assess the reaction of sheep to small artificial shelters and to study the effect of these shelters on the live-weight gain of young lambs in the springs of 1958, 1959 and 1960.

2. Lambs sought shelter particularly when it was raining. They were sensitive to high wind speed and low temperature but did not usually shelter in mild dry weather.

3. Ewes were indifferent to rain and remained in the open in wet weather while many of their lambs sheltered. They occasionally used the shelters for shade in warm sunny weather when their lambs usually went with them.

4. Because of these differences between ewes and lambs in their response to shelter, during wet weather ewes were less closely associated with their lambs where they had access to shelter than where there was no shelter.

5. In the wet spring of 1958, lambs with access to shelter gained weight more slowly than those without shelter. It is postulated that the lambs with shelter may have consumed less milk than the others due to a weaker social bond with their dams.

6. None of the experiments showed that shelter improved the live-weight performance of young lambs.
The performance of different breeds of beef cattle in Cuba
Authors: Willis M. B. , Preston T. R.
Published: September 2010

A method for performance testing beef bulls on a high-energy diet from 90 days of age to 400 kg is described. Test results for 81 bulls showed that both in weight-for-age at 400 kg and feed conversion on test there were significant differences between breeds in favour of the Charolais followed by Santa Gertrudis, Criollo and Zebu in that order. Results for 8 Holstein bulls reared artificially were similar to those for Santa Gertrudis.

Comparative data on birth weights, weaning weights and pre-weaning mortality indicate that the Zebu was inferior to the other beef breeds in all these traits.

Of 60 bulls slaughtered, liver abscesses were encountered in only 2 animals, both of which had been reared artificially from birth.
Castration experiments with Yugoslav Simmental cattle. I. The effect of castration on growth and live-weight gains
Authors: Čobić T.
Published: September 2010

1. Bulls and steers of the Yugoslav Simmental breed (38 in total) were reared and fattened to 470 kg live weight. Half received a moderate level of feeding to 8 months of age and half a high level of feeding over this period; all were fed on a high level from 8 months to slaughter, their diet involving a concentrate mixture, lucerne hay and maize silage.

2. At slaughter weight, steers were 2·5% higher at withers than bulls, but other body measurements showed no significant difference.

3. Castrates needed a 3 to 8% longer fattening period depending on the feeding treatment.

4. Castration reduced the rate of live-weight gain by 4·9% over the whole rearing and fattening period, and by 8·0% over the fattening period only.

5. Bulls had better feed conversion ratios overall. Steers consumed more starch units per kg of live-weight gain—8·1% more over the whole rearing and fattening period and 9·8% over the fattening period. Consumption of digestible crude protein was also higher in steers.

6. The detrimental effect of castration was more strongly expressed on the HH feeding treatment. An increase in the concentration of the rations did not improve food conversion ratios.
Copper supplementation of pig diets. The effect of protein level and zinc supplementation on the response to added copper
Authors: Hanrahan T. J. , O'Grady J. F.
Published: September 2010

1. Five hundred and fifty-two pigs were used in an experiment having six treatments. High and low protein rations were given (a) unsupplemented, (b) supplemented with 0·1% copper sulphate (CuSO4·5H2O) and (c) supplemented with 0·1% copper sulphate and 0·025% zinc carbonate (ZnCO3).

2. Performance was significantly reduced and 18 pigs died from copper toxicosis, when the low protein ration supplemented with copper sulphate was fed.

3. There were no indications of toxicity and performance was equal to the controls when the low protein diet supplemented with copper and zinc was fed.

4. The addition of copper to the high protein diet slightly reduced performance and six pigs died from copper toxicosis.

5. The addition of copper and zinc to the high protein diet improved growth rate and eliminated the toxicity associated with copper supplementation.

6. No significant treatment effects on haemoglobin or packed cell volume
were observed, other than a small effect of protein level on PCV.

7. Copper supplementation of the diets significantly increased liver and kidney copper levels and liver zinc levels. It reduced liver and kidney iron contents. The addition of copper and zinc to the diet reduced the increase in liver copper associated with copper supplementation, and increased the level of zinc in both livers and kidneys.
The rearing of colostrum-deprived piglets
Authors: Perry G. C. , Lecce J. G.
Published: September 2010

1. Four treatments were employed in the rearing of colostrum-deprived piglets from birth to 14 days of age. The performance of the artificially reared piglets was compared with that of conventionally raised sow-suckled piglets.

2. Statistically significant differences in growth rate were found in favour of piglets receiving 22% cows' milk solids from birth when compared with the sow-suckled group and the other artificial treatments.

3. Small non-significant differences in feed conversion efficiency were found between the artificial treatments with one exception. Pigs receiving 22% cows' milk solids from birth possessed superior conversion figures when compared with pigs receiving 6% cows' milk solids after birth.

4. Each of the artificial treatments led to fewer deaths than the sow-suckled group.

5. Pigs on the artificial treatments did not undergo such rapid changes of serum protein profile as did the sow-suckled piglets. Serum protein values for the pigs on the artificial treatments rose from approximately 33% of the levels in the sow-suckled group at two days of age to approximately 60% at 14 days of age.
The distribution of sheep β-lactoglobulins
Authors: King J. W. B.
Published: September 2010

Samples of sheep's milk were used to study the occurrence of β-lactoglobulin variants of fast or slow electrophoretic mobility. The distribution of variant types between a sample of daughters and their dams was in general accord with simple Mendelian expectations for two autosomal co-dominant alleles.
The effect of plane of nutrition during calfhood on the subsequent performance of Hereford × Ayrshire steers
Authors: Broadbent P. J. , Ball C. , Dodsworth T. L.
Published: September 2010

The growth and carcass characteristics of autumn-born Hereford × Ayrshire castrated male calves reared on two planes of nutrition have been studied. Restricted feeding for 12 weeks after weaning from liquid feed to the time the calves were turned out to grass created a difference of 52·0 lb per head in live-weight gain and 15·2 lb of this difference persisted at slaughter. There were small differences in carcass conformation and composition.
The influence of flexible and rigid grazing management and of supplementary feed on output per hectare and per cow
Authors: Leaver J. D. , Campling R. C. , Holmes W.
Published: September 2010

1. A comparison was made of the output per hectare and per cow of 3 systems of grazing management each based on a cycle of 5 days grazing followed by a 20-day rest period. The treatments were: C, strip grazing within a paddock, varying the area allotted so that a similar quantity of herbage was available each day, the pasture being frequently trimmed; treatment R, restricted grazing; the cows being allotted a fixed area of the paddock each day (67–5 m2 per cow per day) which was not trimmed or cut after grazing; and treatment RS, as treatment R but with each cow receiving cereal concentrates. Eight cows were on each treatment. Nitrogenous fertilizer was applied at the rate of 86 kg N per ha [1 kg per ha = 0.891b per acre] four weeks before the first grazing and at the same rate after each grazing; a total of 516 kg/ha was applied. The feed intake of each cow was measured on six occasions during the experiment.

2. The experiment continued for 150 days and the mean stocking rate on treatment C was 4–09 cows per ha [1 ha = 2·47 acre] and on the other two treatments 5·92 cows per ha. The number of cow grazing days per hectare were 610, 890 and 890 for treatments C, R and RS respectively and the outputs of milk were C 8450, R 12 420 and RS 13 380 kg/ha. Allowing for the concentrates given the milk outputs were C 7440, R 10 350 and RS 6660 kg/ha.

3. There were only slight differences between the treatments in output per animal.

4. The average intakes per kg W0·73 were similar in treatment C and R but the average intake of cows on treatment C was more uniform over the season. Cows on treatment RS ate consistently more digestible organic matter than those on treatment C and R but the differences became smaller as the season progressed.
The effect of different dietary energy concentrations on the voluntary intake and growth of intensively-fed lambs
Authors: Andrews R. P. , Kay M. , Ørskov E. R.
Published: September 2010

In a comparative slaughter trial which covered growth from about 16 kg to 40 kg live weight, five groups of six Romney × Swaledale lambs were offeredad libitumfive pelleted diets (A to E) in which rolled barley was gradually replaced by an 80 : 20 mixture of rolled oats : oat husks to the extent that the calculated metabolizable energy (ME) concentration fell from approximately 2–9 (A) to 2·5 (E) Mcal/kg DM.

Although daily live-weight gains did not differ significantly between treatments, the daily carcass gain fell from 143 g/day on A to 105 g/day on E (P<0·05) whereas gut contents increased from 9·9% of live weight to 16·1% (P< 0·001) from A to E. Differences in efficiency of utilization of ME above maintenance were variable but for gross efficiency (i.e. retention/total ME intake), there was a significant decline from A to E.

Dry-matter intakes for the whole experimental period were similar for all five diets, but initially intake was lower for diet E than for A (780v.927 g/day) and ultimately it was higher for E (1410v.1150 g/day). In a second experiment, involving diets A and E and a third diet of chopped dried grass, the pattern of intake and growth changed with live weight in a similar manner to that described above, except that appetite and growth on dried grass were consistently poorer. Daily variation in intake and rumen pH tended to be greater on the concentrate diets.

It is suggested that, amongst other factors, the stage of maturity of an animal may influence the point at which the digestible energy content of the diet restricts dietary intake in preference to physical limitations.
Factors affecting growth of ovine foetuses during early gestation
Authors: Hulet C. V. , Foote W. C. , Price D. A.
Published: September 2010

Year, type of gestation (single or twin foetuses) and age of foetus all had highly significant independent effects on both foetal weight and length (P>0·01). Twin foetuses were both longer and heavier than single foetuses at 21 to 30 days post coitum. Continuous illumination, continuous darkness and intermittent light appeared to reduce foetal length and weight (P>0·05). Control foetuses were longer and heavier than those on other treatments. Neither feeding level (75 to 150% N.R.C. maintenance requirements) nor body weight of the dam had significant effects on foetal size within the age range studied.
Studies on colostral and milk whey proteins in the sow 2. The effect of delayed suckling on colostrum and milk whey proteins
Authors: Bourne F. J.
Published: September 2010

Colostral whey protein levels do not change during the first 4 hr from the start of parturition when suckling is prevented. Both early and late-born piglets returned to the sow at the end of this period are able to suck colostrum of a high protein concentration. Removal of piglets from the sow and the presence of an attendant did not affect the farrowing process.
Genetic parameters of Barki sheep raised under semi-arid conditions
Authors: Fahmy M. H. , Galal E. Salah E. , Ghanem Y. S. , Khishin S. S.
Published: September 2010

Records on 695 lambs were collected over a period of 5 years from 1961/62 to 1965/66, at Ras El-Hekma Desert Research Station, 230 km west of Alexandria. The characters studied were birth, weaning and yearling body weights, pre- and post-weaning daily gains and greasy fleece weight.

Birth, 120-day and 365-day body weights were 3·4, 18·2 and 33·4 kg respectively. Greasy fleece weight at 16 months of age was 3·29 kg. Heritability estimates of birth, weaning, yearling weights, pre- and post-weaning daily gains and greasy fleece weight were 0·22, 0·45, 0·41,0·45 and 0·29 respectively. Genetic and phenotypic correlations between birth, weaning and yearling weights were all positive and significant. Genetic correlations between fleece weight and body characteristics were negative and low.
Studies on the nutritive value of the diet selected by grazing sheep IV. Variation in the diet selected by sheep differing in age, breed, sex, strain and previous history
Authors: Langlands J. P.
Published: September 2010

The ability of two groups of six Merino wethers aged 6 and 66 months to digest a lucerne ration was examined in order to detect possible biases in the use of faecal nitrogen as a faecal index substance. Earlier work with this technique had indicated a difference in selectivity between young and older sheep. No difference in ability to digest the ration was observed and it was concluded that the earlier observation was not an artefact in the faecal nitrogen technique. Oesophageal fistulae were prepared in 120 sheep differing in breed, sex, age, strain and previous history. Determinations were made of the nitrogen content, and in one experiment of the in vitro digestibility of the diet selected by sheep grazing various pastures. Significant differences in the nitrogen content of the diet selected by sheep varying in breed, age and previous grazing history were recorded on some pastures on some occasions but not on others. No significant differences were observed between sheep varying in strain or sex. No reason could be suggested for the occasional differences between groups in the nitrogen content or digestibility of the diet selected, but it appeared unlikely that it would be a major source of variation in the productivity of the different groups at pasture.
Studies on the nutritive value of the diet selected by grazing sheep V. Further studies of the relationship between digestibility estimated in vitro from oesophageal fistula samples and from faecal and dietary composition
Authors: Langlands J. P.
Published: September 2010

Digestibility was estimated in vitro from a total of 167 oesophageal fistula samples collected over a period of 16 to 24 months from adult sheep grazing eight Phalaris tuberosa-Trifolium repens pastures stocked continuously at rates of from 2·5 to 37·1 sheep per ha. Corresponding estimates of the nitrogen content of the faeces and of the fistula samples, the live weight and faecal output of the sheep, and of the herbage availability of the pasture were obtained.

The observations were stratified on the bases of stocking rate, digestibility, month of the year, herbage availability or organicmatter intake. Relationships between digestibility estimated by the fistula technique and faecal nitrogen content (model B) and between digestibility and faecal nitrogen content, nitrogen content of the dietary dry and organic matter, and faecal output per unit live weight (model A) were calculated for each stratum.

There were significant differences between relationships derived for the various stocking rates, levels of digestibility, times of year, levels of intake and levels of herbage availability; predicted values of digestibility for given values of the independent variables differed by as much as 20 units of digestibility. Model A was substantially more precise than model B.

Differences between estimates of digestibility, derived by the fistula technique and by a general faecal nitrogen—digestibility relationship, established by Lambourne and Reardon (1963a) were calculated. The differences were related to digestibility and to herbage availability.

The implications of these results are discussed and it is concluded that faecal nitrogen content is not a satisfactory index of the digestibility of the diet selected by grazing sheep.
A note on lactate dehydrogenase in the blood plasma of Pietrain and Large White pigs
Authors: Hessel-de Heer Jeannette C. M.
Published: September 2010

The LDH values in blood plasma of Pietrains and Large Whites are significantly different during moderate stress (sampling of blood), being higher in the Pietrains. The difference is largest in the LDH-5, the muscle iso-enzyme. Not only are the values higher, but the isoenzyme is also demonstrable in more individual animals.

More stressful situations (forced muscular exercise) result in a rise in plasma LDH-5 in both breeds; the rise is larger in the Pietrains. Two possible causes for the higher LDH-5 values in Pietrain blood plasma are suggested.
The effect of a combination of trenbolone acetate and oestradiol-17β on growth performance and blood, carcass and body characteristics of wether lambs
Authors: Coelho J. F. S. , Galbraith H. , Topps J. H.
Published: September 2010

Nine Cheviot × Shetland castrated male lambs from a group of 24 of 28 kg initial live weight, were subcutaneously implanted with a combination of 60 mg trenbolone acetate and 12 mg oestradiol-17β at 105 days and again at 45 days before slaughter. Of the remaining lambs, nine were untreated and six were slaughtered at the start of the experiment as part of a comparative slaughter procedure. The lambs treated with the anabolic preparation grew significantly faster (P < 0·05), converted food to live weight and estimated carcass gain more efficiently, had heavier carcasses which were larger, and had greater estimated gains for protein, moisture and ash. Implanted animals also tended to have a smaller deposition of carcass and kidney fat, but significantly heavier kidneys and less wool when the latter three weights were related to empty body weight. The mean values for plasma urea and serum total protein as indicators of protein metabolism were significantly decreased and increased respectively in treated lambs, but no other significant differences in blood metabolites and hormones were recorded. A significant increase in teat length of implanted lambs indicated the oestrogenic nature of the anabolic preparation.
Performance of lambs and steers given monensin with different levels of barley
Authors: Horton G. M. J. , Keeler E. H. , Bassendowski K. A.
Published: September 2010

The effect of barley level and monensin on feedlot performance by lambs and steers was investigated in two experiments. Monensin was given at 0 and 33mg/kg of food in lamb and steer diets, which contained bailey at levels from 300 to 900g/kg. Food consumption by lambs was not affected by monensin but intakes decreased with increasing levels of barley (P < 0·05). Food intake by steers decreased in a linear manner with increasing levels of barley (P < 0·01) and averaged 80g/kg lower when monensin was fed (P < 0·05). Monensin improved lamb gains by 350g/kg (P < 0·001), but had no effect on steer performance. Feeding monensin improved average food efficiency in lambs and steers by 27 and 4%, respectively. Carcass characteristics were not influenced by monensin, but heavier carcasses (P < 0·01) in steers given the high barley rations were also fatter (P < 0·001).
A note on the use of the ‘Danscanner’ for prediction of the composition of a sample joint from beef cattle
Authors: Alliston J. C. , Hinks C. E.
Published: September 2010

Forty-five crossbred cattle were scanned by ultrasonics at three sites on the body and were ‘condition scored’ before slaughter and subsequent dissection of a sample rib joint.

Ultrasonic measurements gave a better indicator of fat content than did ‘condition score’. The third lumbar vertebra site on the body gave a better prediction of sample joint composition than did the 10th or 13th rib.

The mean ultrasonic measurement of fat depth at the three sites did not improve the prediction of composition as compared with the value obtained at the third lumbar vertebra. The overall standard deviation for total fat concentration was 42·1 g/kg and for lean concentration was 35·4 g/kg. Area of fat at the third lumbar vertebra was the best single indicator of fat concentration and lean concentration in the sample joint, with residual standard deviations of 25·1 and 23·1 g/kg respectively. A combination of fat measurements at the 3rd lumbar position was the best overall predictor (residual standard deviation: 23·8g fat and 23·0g lean per kg).
A note on the effects of various diets on the drinking behaviour of wether sheep
Authors: Bass Jean M.
Published: September 2010

The mean daily water intakes of individually penned wether sheep were determined over consecutive 7-day periods. Increased intakes of dry matter and/or crude protein resulted in higher intakes of water. The drinking pattern throughout the day was directly related to the type of food offered and its distribution during the day.
Variation in chromium excretion in suckled cows at pasture
Authors: Nicoll G. B. , Sherington J.
Published: September 2010

The diurnal cycle of chromium excretion was estimated over the last 24 h of a 13-day period in which nine single- and nine double-suckled cows were dosed twice daily (10.00 and 16.00 h) with shredded Cr2O3 paper. All faecal passages voided were sampled and analysed for chromium. Rectal samples were also taken at 10.00 and 16.00 h during this period. Sources of variation in the patterns of excretion that could be attributed to cow live weight, daily milk yield or total weight of the calf or calves being reared were also investigated.

Mean faecal Cr concentrations followed a cyclic pattern which was significantly described by a sinusoidal equation.

The estimated fundamental period (0·1334 rad/h) did not differ significantly from the theoretical value (2π/48 = 0·1309 rad/h). Fitting the model for each cow explained from 0·61 to 0·99 of the variation in faecal Cr concentration. Differences between suckling treatments in predicted faecal Cr content at discrete 2-h intervals over the 24-h period were not significant. Equations for heavier cows had lower constant terms, consistent with lower faecal Cr contents expected as a consequence of higher intakes. Differences in cow milk production and total calf live weight being reared were related to the pattern of Cr excretion (P < 0·05) but the reasons for these effects were not readily apparent. Mean Cr concentration in rectal samples was significantly correlated (r = 0·916) with mean 24-h faecal Cr content predicted from the model.
Comparison of eating quality of bull and steer beef
Authors: Dransfield E. , Nute G. R. , Francombe M. A.
Published: September 2010

Eating qualities of beef from entire and castrate male animals were compared using taste panel, objective texture and chemical measurements and a consumer panel. The eating quality of roast m. longissimus dorsi, casseroled m. supraspinatus, minced m. gastrocnemius and grilled m. psoas major from bull beef, slaughtered at 400 days was different (by triangular tests) from that of twin steer beef. The differences (attributed to flavour, texture and juiciness) were not substantiated using descriptive scaling tests when the only significant difference was that roast m. longissimus dorsi from bulls was slightly drier than that from steers. Tenderness, juiciness and flavour of roast m. longissimus dorsi from 71 bulls and 84 steers raised semi-intensively to 390 to 510 kg and slaughtered commercially were assessed using descriptive category scales and the instrumental toughness values. There was no significant difference in organoleptic qualities and the distributions of tenderness and juiciness within these populations were similar. Bull beef contained more connective tissue and had less intramuscular fat. Fatness was poorly related to tenderness (r = 0·3) and unrelated to juiciness or flavour. A consumer panel of 606 assessors showed that bull beef was not as pale as steer beef and found no difference in fatness of the cuts, flavour or juiciness. Fore-rib roasts of bull beef were marginally less tender than steer fore rib.
Methionine supplementation of diets for pigs between 7 and 56 days of age
Authors: Leibholz Jane
Published: September 2010

1. Forty entire male pigs between 7 and 28 days of age and forty entire male pigs between 28 and 56 days of age were fed ad libitum basal diets of wheat and lupins containing 2·4 and 1·9 g of methionine per kg respectively. These were supplemented with 0, 0·3, 0·6, 0·9 and 1·2 g of synthetic methionine per kg of diet.

2. The methionine required for maximum performance and nitrogen retention was 3·0 g/kg of dry matter between 7 and 28 days of age and 2·5 g/kg between 28 and 56 days of age. These values were equivalent to 1·14 and 1·19g/100g of dietary crude protein at the two ages. The cystine contents of the diets were 3·7 and 3·1 g/kg respectively.

3. The concentration of methionine in the blood plasma did not give a clear indication of methionine requirement.
Comparative performance of six Holstein-Friesian × Guzera grades in Brazil 3. Burdens of Boophilus microplus under field conditions
Authors: Lemos A. M. , Teodoro R. L. , Oliveira G. P. , Madalena F. E.
Published: September 2010

Burdens of ticks (Boophilus microplus) on young and adult females (heifers and cows) of six red-and-white Holstein-Friesian (HF) × Guzera (G) grades were assessed by counting the number of semi-engorged tick females on the right side of the animals. The HF grades were: ¼ ½ ⅝ ¾ ⅞ and ≥ Assessments of tick burdens of heifers were made on twelve occasions (357 observations on 193 animals). Cows were assessed six times (380 observations on 83 animals). Cows and heifers were in different pastures. Data were transformed to log10 (2 × count + 1) to normalize their distribution. Direct breed additive (g1, HF-G) and heterosis (hl) effects were estimated within dates of counting. Estimates of h1 on the log scale were not significant (P > 0·05) on 11 out of 12 dates for heifers and on five out of six dates for cows. Estimates of g1 for heifers varied from 0·505 (s.e. 0·492) to 2·376 (s.e. 0·345) (mean g1 = 1·575 (s.e. 0·096)), and estimates for cows varied between 1·009 (s.e. 0·203) and 2·293 (s.e. 0·219) (mean g1 = 1·416 (s.e. 0·080)). These results indicate the presence of important genetic effects on tick burdens. The means of the untransformed number of ticks per animal were, for the six grades in the above order, respectively: 44, 71, 151, 223, 282 and 501, for heifers, and 7, 19, 31, 64, 62 and 97 for cows.
A note on the Charolais and Murray Grey as terminal sire breeds
Authors: Morris C. A. , Baker R. L. , Bass J. J. , Johnson D. L.
Published: September 2010

A comparison was made of the carcass characteristics of 73 Charolais-sired and 86 Murray Grey-sired cattle slaughtered at about 20 months of age. Six Charolais and 10 Murray Grey sires were used. At a constant slaughter age (597 days) the Charolais-sired calves had significantly heavier pre-slaughter live weight (36 kg) and carcass weight (24 kg) and significantly less fat over the m. longissimus (2·8 mm), but there was no significant difference in killing-out proportion. In the dissected half-carcass, the Charolais-sired calves had significantly more meat (9·3 kg), more bone (3·5 kg) and less fat (1·9 kg). At a constant carcass weight (233 kg), Charolais-sired calves had significantly more meat (1·8 kg) more bone (1·9 kg) and less fat (3·5 kg) in the dissected side. After making allowance for the higher calf mortality from birth to weaning of Charolais-sired calves (0·041), the advantage in carcass weight was reduced to 13 kg. It is concluded that the Charolais breed is superior to the Murray Grey as a terminal sire.
A note on calculating the benefit from replacing one breed by another
Authors: Sutherland R. A.
Published: September 2010

Formulae are derived to calculate the genetic merit of a commercial population during replacement of one breed by another, based on the rates of genetic change in the old and new breeds, the initial difference between the breeds, the lag between the first use of replacement stock and the appearance of their genes in commercial progeny and the effect of replacement on the old breed improvement scheme. By comparing the merit of the population with and without replacement the value of a change in breed can be assessed. The method is illustrated with an example from pig breeding.
Carcass composition of crossbred lambs by ten sire breeds compared at the same carcass subcutaneous fat proportion
Authors: Croston D. , Kempster A. J. , Guy D. R. , Jones D. W.
Published: September 2010

An evaluation was carried out over a 5-year period in 10 commercial flocks of Scottish Blackface, Scottish Half-bred and Mule ewes to examine the carcass characteristics of 10 sire breeds: Border Leicester, Dorset Down, Hampshire Down, He de France, North Country Cheviot, Oxford Down, Southdown, Suffolk, Texel and Wensleydale. An average of 43 sires was used per sire breed.

The analyses involved tissue separation data for a total of 1402 lambs. Analyses were carried out separately for early and late flocks determined by the time of the year in which lambs were slaughtered. Sire breeds were compared when their progeny were slaughtered at the same carcass subcutaneous fat proportion (125 g/kg, early flocks; 116 g/kg, late flocks).

Texel crosses had the highest carcass lean proportion (P < 005); their advantages over the Suffolk crosses were 19 g/kg (early flocks) and 17 g/kg (late flocks) reflecting both a higher lean:bone ratio and a higher lean:fat ratio. The Suffolk crosses had a similar carcass lean proportion to other breed crosses. Border Leicester, North Country Cheviot, Texel and Wensleydale crosses tended to have less of their total lean distributed in the higher-priced joints than the Down breed crosses. However, the differences were relatively small and not of major commercial significance: the range between sire breeds was 0-01 to 0-02 of average retail value.