bluuebunny/crossref_metadata_2025 huggingface dataset:
Behavioural relationships between Merino ewes and lambs during the four weeks after birth
Authors: Morgan P. D. , Arnold G. W.
Published: September 2010

The attachment between the ewe and her lamb, as assessed by estimating the distance between ewe and lamb and observing their behaviour, was studied for the 4 weeks after birth. The ewe and lamb kept in close contact throughout this period. They were within 10 metres of each other in 56% of all observations; only in 6% of all observations were they more than 50 metres from each other. With increasing age of lamb, the ewe spent more time grazing while the lamb also spent more time grazing and playing and less time sucking. The lambs showed independent forms of behaviour such as the formation of groups as they got older. The distinct dependent behaviour traits were that if bothewe and lamb were lying or walking, then they were usually close together.

The mean distance between ewes and lambs remained constant for dependent forms of behaviour but gradually increased with age for independent forms of behaviour.
The effects of method of processing on the intake and digestibility by lambs of dried perennial rye-grass and tall fescue
Authors: Tetlow R. M. , Wilkins R. J.
Published: September 2010

Cobs and pellets which differed in particle size (modulus of fineness, MF) were prepared from dried perennial ryegrass and tall fescue and given to sheep. The MF values of the feeds were 2·45,1·09,0·81 and 0·74 for perennial ryegrass and 2·28,0·84,0·67 and 0·57 for tall fescue. Organic matter digestibility was similar for the two grass species when measured in vivo, but when measured in vitro values for perennial ryegrass were about 3 units higher than those for tall fescue. Voluntary intake and live-weight gain were higher for sheep given tall fescue, the difference in live-weight gain being just significant at P < 0·05. The response to change in particle size was similar for the two grass species. Intake was lowest and digestibility highest for the feeds with the highest MF, but differences between the three finely-ground forms of each species were not significant. There was a tendency for the intake of digestible organic matter to be lower for the feeds with lowest MF than for those with intermediate values for MF. The rate of passage of undigested particles was slower for cobs with the highest MF than for the other feeds, which did not differ significantly one from another.
Effects of plane of nutrition in late pregnancy on lamb birth weight and milk yield in early lactation of Chios and Awassi sheep
Authors: Louca A. , Mavrogenis A. , Lawlor M. J.
Published: September 2010

Two trials were conducted using two breeds of sheep varying in prolificacy but producing high commercial milk yields. In the first, 85 Chios ewes were assigned at 10 weeks before lambing to one of three planes of feeding: L, straw ad libitum; M, straw ad libitum + 0·5 kg concentrates; and H, straw ad libitum +1·0 kg concentrates. Six weeks prior to lambing, treatment L was stopped and all 85 ewes were re-randomized to treatments M and H. They were kept on these treatments until 14 days after lambing. In the second trial, 54 Chios and 56 Awassi ewes were allocated to the M and H treatments 6 weeks prior to lambing. After lambing they were fed ad libitum on straw and concentrates for 28 days.

The mean metabolizable energy intake (Meal/day) over the 6-week period before lambing was 2·78 and 3·96 for Chios ewes in Trial 1, 2·39 and 3·51 for Chios ewes in Trial 2 and 2·66 and 3·72 for Awassi ewes in Trial 2, for the M and H treatments respectively.

In both trials the treatment of the ewes affected the birth v/eight of twin and triplet lambs but not that of singles. In Trial 1, the differences in 14-day milk yield between treatments M and H were highly significant. In Trial 2, however, in which the ewes were fed ad libitum during lactation, no differences in the 14-day or the 28-day milk yields were observed for either breed. It is concluded that milk yields in early lactation are closely related to actual plane of nutrition in lactation but may also be affected by the body condition of the ewe at lambing, which may in turn be influenced by a low level of feeding in pregnancy.
Nutritional evaluation of wheat 1. Effects of preparation on digestibility of dry matter, energy and nitrogen in pigs
Authors: Ivan M. , Giles L. R. , Alimon A. R. , Farrell D. J.
Published: September 2010

1. A split-plot design was used to study apparent digestibility of dry matter, gross energy and nitrogen of a whole grain wheat diet and processed (hammermilled, rolled or hammermilled and then steam-pelleted) wheat diets by eight small (33·9 ± 0·1 kg) and eight large (70±1·7 kg) pigs. Metabolizable energy and nitrogen retention were also studied with the small pigs.

2. The processed wheat diets were superior to the whole grain wheat diet in all the parameters measured.

3. There were no significant differences between the performance of pigs given the differently processed wheat diets.

4. Apparent digestibility of dietary components particularly in the whole wheat diet was significantly higher when diets were given to small pigs than when given to large pigs.
Thyroxine and wool follicle activity
Authors: Ryder M. L.
Published: September 2010

Serum thyroxine levels were observed in 15 Soay ewes and seven rams for 1 year. From June to November the ewes had thyroxine concentrations 40% higher than the rams, and the level in both sexes increased from December to May, demonstrating a seasonal cycle in thyroxine level that could be associated with the annual wool growth cycle. To hasten the onset of wool follicle activity, nine Wiltshire sheep were given thyroxine implants in autumn when the follicles normally become inactive, but only a slight increase in follicle activity occurred. Eighteen Soay sheep were given thiouracil orally for 1 month in spring in an attempt to block a possible seasonal increase in thyroxine secretion that might be associated with the normal regrowth of wool, but no retardation of the spring regrowth was obtained.
A note on nutrition during late pregnancy in West African Dwarf sheep
Authors: Adut I. F. , Olaloku E. A.
Published: September 2010

Three groups, each of 12 West African Dwarf ewes weighing 17·5 kg at mating, had mean daily digestible organic matter intakes over the final 7 weeks of pregnancy of 249, 435 and 538 g/ewe (Treatments I, II and III respectively). Mean plasma concentrations in Treatments I, II and III were: glucose, 384, 527 and 538mg/l; non-esterified fatty acids (NEFA), 672, 441 and 427 μequiv/1; and ketones, 44·1, 30·5 and 27·3 mg/1. The differences in all metabolites between Treatment I and Treatments II and III were significant (i) <0·001). The mean birth weights of the single lambs from ewes in Treatments I to III were 1·1, 1·7 and 1·8 kg, those from ewes in Treatment I being significantly lighter than those from ewes in Treatments II and III. Lamb birth weights were significantly and positively related to energy intake and to plasma glucose concentrations, and significantly and negatively related to plasma NEFA and ketone concentrations.

The results indicate that the effect of undernourishment during late pregnancy in West African Dwarf sheep may be greater than in European breeds, and that the concentrations of blood metabolites may have a use in monitoring and regulating nutritional state in this genotype.
Maize silage for milk production: The influence of concentrate supplementation and the effect of adding urea or ammonia before feeding
Authors: Aston K. , Daley S. R. , Tayler J. C.
Published: September 2010

1. Thirty lactating British Friesian heifers and cows were individually given maize silage ad libitum containing 331 g dry matter/kg, 13 g nitrogen and 11·2 MJ of metabolizable energy per kg dry matter. Urea or aqueous ammonia was mixed in at the time of feeding to give 7·0 g nitrogen per kg silage dry matter. Urea-treated silage was given with concentrates at a high (mean 6·6 kg dry matter/day: treatment HU) or a low (mean 3·3 kg:treatment LU) level of feeding; the lower level only was given with ammonia-treated silage (treatment LA).

2. The addition of ammonia raised silage pH values from 3·9 to 4·4. Silage dry-matter intakes in lactation weeks 7 to 22 for treatments HU, LU and LA were 8·8, 11·1 and 10·7 kg/day.

3. Digestible organic matter content in the dry matter of the diets measured in vivo was not significantly affected by treatment. However, digestible organic matter intakes were significantly greater for treatment HU than for LU in weeks 7 to 10, and for LU than for LA in weeks 11 to 22.

4. The yields of milk and the contents of protein, lactose and energy did not differ between treatments. The milk yields for treatments HU, LU and LA in weeks 7 to 22 were 20·2,19·2, 18·8 kg/day respectively. Fat content of milk was significantly depressed with the HU treatment for heifers in weeks 7 to 10. The live-weight changes of the cows in weeks 7 to 22 for treatments HU, LU and LA were +0·10, −0·07 and −0·37 kg/day; the live-weight loss by cows given treatment LA was significantly greater than for LU. The live-weight change of the heifers was not affected by treatment.
Failure to recycle after weaning, and weaning to oestrus interval in crossbred sows
Authors: Fahmy M. H. , Holtmann W. B. , Baker R. D.
Published: September 2010

Failure to recycle after weaning and the interval from weaning to oestrus were studied using sows representing 28 crosses from eight breeds at three stations. Of the sows farrowing their first litter, 12·9% failed to recycle within 50 days. The least squares mean for weaning to oestrus interval for all crosses was 13·5 days. Hampshire × Landrace, followed by Hampshire × Yorkshire sows had the shortest intervals (8·0 and 8·7 days respectively) whereas Large Black × Lacombe sows had the longest interval (22·1 days). Crosses involving the Yorkshire, Hampshire, Berkshire and Tamworth breeds had shorter intervals than those involving Landrace, Duroc, Large Black and Lacombe. Season of farrowing had significant effect (P < 0·05), with the shortest interval (11·4 days) occurring in autumn and the longest (15·1 days) in spring and summer. Weaning to oestrus interval increased with the increase in litter size. The interval was longer (15·7 days) at Lennoxville but similar at the other stations. There was a steady increase in size in the following litter with the increase in the weaning-oestrus interval. The heritability estimate (full-sib analysis) for the weaning-oestrus interval was 0·25 ± 0·10. Repeatability based on limited data was calculated at 0·28.
The administration of sugar solutions to pigs immediately prior to slaughter 2. Effect on carcass yield, liver weight and muscle quality in commercial pigs
Authors: Fernandes T. H. , Smith W. C. , Ellis M. , Clark J. B. K. , Armstrong D. G.
Published: September 2010

Three field trials were undertaken to determine the influence of feeding sugar solutions to pigs immediately prior to slaughter on carcass yield, liver weight and muscle quality. In the first, which involved 168 pigs of 85 to 95 kg live weight, provision of a glucose syrup solution in lairage (4 h) followed by water (12 h), compared with water-only (16 h) increased carcass yield (3%) and liver weight (27%) and reduced muscle ultimate pH (0·1 to 0·4 unit). When water was not made available after consumption of the sugar there was no response in carcass yield. In the second trial conducted with 169 pigs of 110 to 125 kg live weight, and involving the same treatments as in Trial I, except that sugar was provided for a longer period (6 h), corresponding responses in carcass yield, liver weight and muscle ultimate pH were +2·7%, +24% and a decrease of 0·2 to 0·3 units. In both trials responses to sugar feeding were less when compared with pigs slaughtered shortly after arrival at the abattoir. In the final trial, which also involved heavy pigs (88), access to a glucose syrup solution (9 h), but not a sucrose one, followed by water (8 h), relative to water-only in lairage, improved carcass yield (1·1%). Liver weight was increased with glucose (34·2%) and markedly so with sucrose (49·7%) and both sugars reduced muscle ultimate pH (0·1 to 0·6 units).
Effect of fermentation and palm oil on the performance of broilers receiving cassava diets in the tropics
Authors: Adeyanju S. A. , Pido P. P. , Adegbola A. A.
Published: September 2010

The effect of fermentation on cassava meal diets supplemented with 0, 2, 4 and 6% levels of palm oil on the performance, carcass characteristics and economic value of broiler chickens was studied. During the growing phase, fermentation had no influence on growth rate, but resulted in reduced mortality and improved efficiency of feed utilization in the chickens. However, there were greater intakes of fermented cassava meal diets, higher efficiency of feed utilization, better growth rate and reduced mortality during the finishing phase. Abdominal fat was lower during both phases in chickens given the fermented cassava meal diets than those given the cassava meal diets. There was evidence of economic benefits in reduced feed cost, increased gross revenue and higher revenue less feed cost values in fermented cassava meal than in cassava meal diets. There were non-significant reductions in feed intake, mortality rate, daily rate of gain, final body weight and carcass quality, but significant economic benefits during both growing and finishing phases as the level of supplementary palm oil increased in the diets. The results suggest that while about 2% palm oil might be required in fermented cassava meal diets, 2 to 4% would be needed in cassava meal diets by broiler chickens for comparable performance.
The effect of time of mating on ovulation rate and potential lambing rate of Greyface ewes
Authors: Gunn R. G. , Doney J. M. , Smith W. F.
Published: September 2010

Over 2 years, 104 Greyface ewes were mated at a synchronized oestrus either in early October or early November. From late September until slaughter at return to service or between 4 and 7 weeks after mating, ewes were fed to maintain their body condition score as previously adjusted by differential group feeding on grass. Ovulation rate and potential lambing rate were derived from counts of corpora lutea and viable embryos at slaughter. Both rates were higher in the early-mated ewes in comparable body condition. Stress factors were implicated as contributing to the decline in ovulation rate with time, while ewes which failed to hold to first mating were largely responsible for the decline in potential lambing rate.
The administration of sugar solutions to pigs immediately prior to slaughter. 3. Effect on bacon yield
Authors: Fernandes T. H. , Smith W. C. , Ellis M. , Clark J. B. K. , Armstrong D. G.
Published: September 2010

Two field trials were conducted with 138 and 123 bacon-weight pigs respectively from one farm to determine the effect on bacon yield of feeding the animals sugar solutions prior to slaughter. Three treatments were tested: immediate slaughter on arrival at the abattoir; lairage overnight with access to water only (15 h); and overnight lairage with access to a sugar solution (6 h) followed by water only (9 h) prior to slaughter. A glucose syrup solution was used in one trial and a sucrose solution of similar hexose-equivalent concentration (550 g/kg) in the other. Access to either of the sugar solutions, relative to water only or immediate slaughter, increased bacon yield. This was entirely due to glucose-fed pigs having a higher carcass yield (2·3 % and 1·5 % respectively) and a trend in this direction for the sucrose-fed animals (0·9% and 1·0% respectively). Carcasses of glucose-fed pigs actually gained less weight than those of their counterparts during the curing process, but this did not occur with the sucrose solution. Access to sucrose relative to water only and immediate slaughter increased liver weights by 32% and 42% respectively. Lower hepatic responses were obtained with glucose syrup (18% and 12%). Both sugar solutions reduced muscle ultimate pH (0·1 to 0·2 unit) relative to water only in overnight lairage.
Late pregnancy ewe feeding and lamb performance in early life. 1. Pregnancy feeding levels and perinatal lamb mortality
Authors: Khalaf A. M. , Doxey D. L. , Baxter J. T. , Black W. J. M. , FitzSimons J. , Ferguson J. A.
Published: September 2010

One hundred and thirty-nine Scottish Half bred ewes were studied during the last 8 weeks of pregnancy, through parturition and early lactation. They were divided, on the basis of their metabolizable energy intake during this period, into low (483 MJ/ewe; L), medium (742 MJ/ewe; M) or high (974 MJ/ewe; H) feeding groups.

Ewe weight change (from mating to 12 h post lambing) was directly related to nutritional level and the number of lambs born, e.g. L ewes with triplets lost a mean 13·8 kg, while H ewes with single lambs gained 14·3 kg.

Lamb birth weight and perinatal lamb mortality levels were affected by ewe nutrition and litter size. L twins weighed 19% less at birth than H twins; L triplets weighed 26% less than H triplets. The mortality rate of L twins was 23% greater than M twins; L triplets exceeded the H triplet mortality rate by 87%.

Ewe energy feeding during late pregnancy affected the mean daily weight gain of lambs for at least 3 weeks after birth. H single, twin and triplet lambs grew 12%, 15% and 16% faster than M lambs and 19%, 31 % and 31 % faster than L lambs respectively.

The H group produced 33 % more lamb live weight at 3 weeks of age for every lamb born than did the L group.

Lamb serum immunoglobulin levels were related to litter size but did not reflect the differences in ewe feeding during late pregnancy.
Constrained selection by independent culling levels
Authors: Evans R.
Published: September 2010

The problem of applying a linear constraint on expected selection responses in a two-character independent culling levels scheme is investigated. A general equation is derived, the solutions of which specify the culling levels satisfying the constraint applied. Examples are given to demonstrate how different constraints can be applied by transforming one or more of the characters under selection.
Efficacy of feed additives in enhancing performance of growing pigs
Authors: Veum T. L. , Lauxen R. , Yen J.-T.
Published: September 2010

The efficacy of feed additives in enhancing the performance of growing pigs, together with the effect of different protein levels (18 v. 16% from 13 to 18 kg body weight and 16 v. 14% from 18 to 39 kg body-weight), were evaluated in three experiments with 412 pigs. In Experiment 1, from 13 to 39 kg body weight, pigs receiving 55 p.p.m. carbadox (C) produced a greater (P<0·05) average daily live-weight gain than did the non-medicated (NM) pigs and those receiving 275 p.p.m. chlortetracycline-sulphamethazine-penicillin (ASP) with a similar but non-significant (P>0·05) trend n i daily feed intake and gain/feed ratio. The ASP pigs also produced a greater (P<0·05) weight gain than the NM pigs. The higher dietary protein level sequence produced a greater (JP<0·05) weight gain and gain/feed ratio.

In Experiment 2, from 16 to 39 kg body weight, NM control pigs achieved high weight gains, and all the feed additive treatments studied [C+106 p.p.m. of the worming agent pyrantel tartrate (C+P); ASP+8 mg of the worming agent levamisole-HCl per kg body weight fed once on day 7 of the experiment (ASP+L); and 113 p.p.m. tylosin+13 p.p.m. of the worming agent hygromycin B] were similar to the NM controls in daily feed intake, weight gain and gain/feed ratio. However, in Experiment 3, the C+P and ASP+L treatments resulted in a greater (P<0·05) weight gain with a trend toward greater daily feed intake than did the NM control treatment from 17 to 35 kg. The weight gain of the ASP+L pigs was also greater (P<0·05) than that of 165 p.p.m. oxytetracycline and NM pigs from 35 to 57 kg. From 57 to 96 kg all the pigs received the same NM control diet and their weight gains were similar. The gain/feed ratio was similar among the treatments within each of the weight periods in Experiment 3. Pigs slaughtered at the beginning and at various stages during Experiments 2 and 3 were free of internal parasites and migration damage.
Breed and sex differences in muscle distribution in equally mature sheep
Authors: Taylor C. S. , Mason M. A. , McClelland T. H.
Published: September 2010

Sheep from the Soay, Southdown, Finnish Landrace and Oxford Down breeds were serially slaughtered at 40, 52, 64 and 76% of their estimated mature body weight. Breed and sex comparisons of muscle distribution wee made at these degrees of maturity. Comparisons were based on 12 individual muscles obtained from the prime retailjoints. Together, these 12 muscles represented about 41 % of total weight ofmuscle in the carcass. Highly significant breed and sex differences in the weight of individual muscles were obtained, but these differences were greatly reduced when values were expressed as a percentage of total muscle weight.

On a percentage basis, there were significant changes with stage of maturity in only three of the muscles studied, although most individual muscles showed an initial percentage decrease with increasing maturity (from 40 to 52%) but almost no change thereafter. Significant breed differences in muscle distribution were found. The individual muscles examined, when combined, comprised 40·8, 43·4, 40·5 and 39·8 % of total muscle weight respectively in the Soay, Southdown, Finnish Landrace and Oxford Down. No breed was significantly above average for every individual muscle, but the Southdown had the highest percentage in 6 out of 12 and might therefore be said to have had the most preferred muscle distribution. For most muscles examined, the percentage was slightly higher for females than for males, with totals for all 12 muscles of 41·9 and 40·4% respectively.
Genetically standardized growth equations
Authors: Taylor C. S.
Published: September 2010

The genetic size-scaling rules recently proposed by the author are used to derive genetically standardized growth equations.
Abnormal patterns of ovarian activity in dairy cows and their relationships with reproductive performance
Authors: Claire Bulman D. , Wood P. D. P.
Published: September 2010

Progesterone profiles were obtained from 533 dairy cows during the interval from calving to the re-establishment of pregnancy by twiceweekly radioimmunoassay of milk progesterone. The importance of abnormal patterns of ovarian activity on herd fertility was determined. Animals were divided into five categories based on profile analysis: A, normal; B, delayed start to ovarian cycles; C, cessation of cycles; D, prolonged luteal activity; and E, silent oestrus. Animals in categories B to E were subdivided into treatment groups: categories B and C either (i) untreated controls, (ii) single injection 0·5 mg luteinizing hormone-releasing hormone (Hoechst) or (iii) progesterone-releasing intravaginal device (Abbott Laboratories Ltd) inserted for 14 days; categories D and E either (i) untreated controls or (ii) single injection 0-5 mg cloprostenol (Imperial Chemical Industries).

The proportion of cows in each category was: A 77·5%; B 4·9%; C 5·1%; D 1·9%; and E 10·7%. The incidence of ‘normal’ cows was 75% (first lactation), 80% (2nd to 5th lactations) and 69% (5th to 11th lactations). For normal cows (no. = 413) the interval to the start of cyclicity varied significantly with season but was not correlated with either the intervals to first insemination or to conception. In categories B to E the open period, the number of services per conception, and the days from first insemination to conception were greater than in category A, but only in category C were any differences significant. None of the treatments reduced calving-toconception intervals.
Genetic and environmental influences on beef cattle production in Zambia 1. Factors affecting weaner production from Angoni, Barotse and Boran dams
Authors: Thorpe W. , Cruickshank D. K. R. , Thompson R.
Published: September 2010

Factors influencing reproductive performance and calf and dam live weights were examined for two indigenous breeds, Angoni and Barotse, and an introduced breed, Boran, under ranching conditions in Zambia.

Over 5 years, 675 Angoni, 731 Barotse and 815 Boran records gave calving percentages of 82·5, 78·1 and 75·4 respectively. Year was an important influence on calving and weaning percentages in all breeds; age of dam had little effect and status at mating was only important in the Angoni breed, in which lactating dams produced more calves than dry dams.

Mean calf weaning weights were 147·3, 167·0 and 169·5 kg for the Angoni, Barotse and Boran dam breeds respectively. Hereford, Friesian and Boran bulls sired heavier progeny than Angoni and Barotse. Dam age and status did not influence calf weights, which were positively correlated with dam weights and negatively correlated with dam weight change during lactation.

Dam live weights at the beginning of the breeding season were 313, 357 and 348 kg for the Angoni, Barotse and Boran breeds respectively. Angoni and Boran dams reached maximum live weight at 7 years and Barotses at 9 years. Subsequent calving rate was not influenced by live weight at the beginning of the breeding season nor, in lactating dams, by live-weight change between the autumn peak and mid breeding season.
The effect of subclinical nematode parasitism on digestion and performance in growing pigs
Authors: Pattison H. D. , Thomas R. J. , Smith W. C.
Published: September 2010

A preliminary trial established a subclinical level of infection with Oesophagostomum dentatum capable of affecting the performance of growing pigs. Thereafter a slightly higher level of infection (100 000 larvae) was administered to each of 24 individually- and scale-fed pigs to investigate the effect of O. dentatum on performance, digestibility and nitrogen retention over the live-weight range 32 to 64 kg. Worm-free but otherwise similar pigs served as controls. Infection reduced growth rate (12·9 %) and decreased efficiency of feed conversion to body weight (14·9%). There was no effect on killing-out percentage or area of eye muscle in cross-section, but infected pigs had relatively lower backfat depths (5·5 to 12·5 %). Infection did not influence nitrogen retention, but apparent digestibility of the dry matter, organic matter, nitrogen, gross energy and crude fibre was reduced. Possible explanations for these effects are discussed in relation to tissue changes associated with larval development in the large intestine.
The influence of nutrition in early lactation on the performance of spring-calving suckler cows and their calves
Authors: Hodgson J. , Peart J. N. , Russel A. J. F. , Whitelaw A. , Macdonald A. J.
Published: September 2010

Twenty-four Hereford × Friesian cows (HF) and 24 Blue-Grey (Whitebred Shorthorn × Galloway) cows (BG) were housed in individual stalls. For the last 12 weeks of pregnancy they were fed hay to supply 75% of estimated maternal maintenance energy requirements. From calving (11 February to 9 April) until turning out to graze on 15 May they were given hay for maintenance, and a concentrate sufficient for either 2·25 kg (L) or 9·0 kg (H) milk per day, balanced within genotype. From 15 May until the end of the experiment on 7 September the cows and calves grazed as a single herd in a paddock grazing system, at a controlled daily herbage allowance of 50 g dry matter, measured to ground level, per kg total weight of cows and calves.

Cows on Treatment L lost more weight between calving and turnout than those on Treatment H, gave less milk, and their calves grew more slowly and were lighter at turn-out. Milk yields increased substantially after turn-out. Subsequently, milk yields and calf growth rates, and herbage intakes by the cows, did not differ significantly, although all were marginally higher for animals previously on Treatment L. Final calf weights, cow weights and cow body condition scores did not differ significantly.

Calves from HF cows were heavier at all stages than calves from BG cows. HF cows were heavier at calving than BG cows, gave more milk (though the difference was not significant) and lost more weight in early lactation. Final live weights and condition scores did not differ significantly.

The limited evidence suggested that conception to artificial insemination following oestrus synchronization was not affected by plane of nutrition in early lactation.
Utilization of glucosev. lactose in an isolated soya bean protein diet by neonatal piglets reared artificially
Authors: Mateo J. P. , Veum T. L.
Published: September 2010

Forty-eight 1-day-old pigs were used to compare lactose and glucose as the carbohydrate source for piglets from 1 to 22 days of age. Average daily gains, gain over feed ratios and the apparent digestion coefficients for crude protein, ether extract, nitrogen-free extract, ash, energy and dry matter were similar for the two groups. Apparent net protein utilization was greater with the glucose diet than with the lactose diet (P<0·05), although their apparent biological values and metabolizable energy values were similar. The serum levels of total glucose, total protein and urea nitrogen were also similar for both groups. Serum levels of total protein and urea nitrogen declined with age while the trend for total glucose was inconsistent. Subsequent nursery performance from 22 to 64 days of age when all pigs were fed the same diet was not influenced by the previous neonatal dietary treatment.
Live-weight growth from embryo to adult in domesticated mammals
Authors: Taylor C. S.
Published: September 2010

The inter-species relationship between mature body weight and time taken to mature in body weight was studied empirically in nine domestic species with data ranging from early embryonic to late postnatal growth. When examined in terms of genetic size scaling, the results showed that metabolic age provided a readily useable comparative age scale which would allow results obtained from one species to advance the study of growth and nutrition in other species.

A standardized growth curve was therefore calculated for each species in terms of degree of maturity in body weight and metabolic age. The two standardized regression curves gave mean growth curves that estimated expected degree of maturity at a given metabolic age and expected metabolic age at a given degree of maturity. The two mean curves scarcely differed.

Deviations of each species from these mean curves were analysed. There were significant standardized differences between species in earliness of maturing. Rabbits were estimated to mature in 30% less time than expected for their size, a deviation which (if repeatable) could be of great potential importance to animal production.
Effects of supplementing maize and grass silages with barley, and maize silage with urea or ammonia, on the intake and performance of fattening bulls
Authors: Aston K. , Tayler J. C.
Published: September 2010

1. Experiment 1. Six treatment groups of one British Friesian and four South Devon × British Friesian bulls, initially 432 kg mean live weight and aged 491 days, were offered individually maize or grass silage ad libitum plus 0, 5 or 10g barley dry matter per kg live weight daily for 80 days. The silages had similar digestible dry matter and estimated metabolizable energy contents but the grass silage contained more ammonia and acetic, propionic and butyric acids. Mean values for groups receiving respectively maize and grass silage diets were for dry-matter intake 17·7, 20·3, 20·4 and 13·0, 16·6, 18·7 g/kg live weight and for live-weight gain 1·00, 1·32, 1·46 and 0·65, 0·98, 1·22kg/day. Significantly more maize than grass silage dry matter was eaten when the silages were given alone and dry-matter intakes, live-weight and carcass gains were greater for maize silage diets. Dry-matter intake, live-weight and carcass gains, efficiency of feed use and carcass quality significantly improved when barley was given.

2. Experiment 2. Six groups of five British Friesian bulls, initially 418 kg mean live weight and aged 474 days, were offered individually maize silage ad libitum with either urea or one of two quantities of aqueous ammonia mixed in at the time of feeding, plus 0 or 5 g barley dry matter per kg live weight daily for 90 days. The urea and ammonia-treated silages contained 125, 124 and 148 g crude protein per kg dry matter respectively, with pH values of 3·8, 3·9 and 4·3, and when given alone or with barley mean daily intakes (g dry matter per kg live weight) were 17·1, 18·6 for urea-treated silage diets, and 17·8, 18·8 and 16·9, 19·1 respectively for ammoniatreated silage diets. Live-weight gains were 0·69, 0·94, 0·63, 1·09, 0·64 and 1·07 kg/day. Ammonia treatment had no effect on intake or live-weight gain. Live-weight and carcass gains and carcass quality improved when barley was given.

3. The maize silage offered in Experiment 1 contained similar metabolizable energy but more starch than that in Experiment 2 and was used more efficiently for live-weight gain.
Digestible energy content of cereals and wheat by-products for growing pigs
Authors: Batterham E. S , Lewis C. E. , Lowe R. F. , McMillan C. J.
Published: September 2010

1. The digestible energy content of eight samples of barley, sorghum, wheat, weather-damaged wheat and wheat by-products produced from different regions of eastern Australia was determined using growing pigs. The relationships between physical and chemical composition and digestible energy content of the meals were studied.

2. The mean and range in digestible energy (MJ/kg, air-dry basis) were, respectively: barleys 12·7 (12·4 to 13·0), sorghums 14·4 (14·1 to 14·9), wheats 14·4 (14·0 to 15·0), weather-damaged wheats 14·1 (12·9 to 14·9) and wheat by-products 12·4 (10·9 to 14·1).

3. All possible regressions of digestible energy content against density, gross energy and proximate analyses of the meals were screened to select useful relationships. These screens indicated that, with the exception of wheat by-products, the majority of variation in digestible energy was due to gross energy and fibre. For wheat by-products, a combination of density and fibre accounted for most of the variation.

4. Prediction equations had the most application to weather-damaged wheats, wheat by-products and a combination of all samples.

5. There was no indication that neutral-detegent fibre was superior to crude fibre as a predictor of digestible energy in cereals for pigs.
Genetic parameters of growth and carcass composition in crossbred lambs
Authors: Wolf B. T. , Smith C. , King J. W. B. , Nicholson D.
Published: September 2010

Data were available on crossbred meat lambs for 10 live-weight and growth traits (2585 lambs), 5 carcass traits (1884 lambs) and 10 dissection traits (944 lambs). These were the progeny born on an experimental farm over 5 years, from 102, 79 and 65 sires respectively for the three groups of traits. Genetic parameters were estimated from the sire components in a nested analysis of variance within breed of sire and year subclass, adjusting for sex, dam age, rearing type and other factors.

The heritabilities of the live-weight and growth traits were all low, the highest being average daily gain to slaughter (0·10, s.e. 0·06), and none was statistically significant. The heritabilities of the traits of carcass composition were much higher: percentage lean (0·41, s.e. 0·13), percentage fat (0·37, s.e. 0·13) and percentage bone (0·16, s.e. 0·10). Intermediate values were found for most other traits: killing-out percentage (0·16, s.e. 0·07), fat depth (0·21, s.e. 0·11), eye-muscle area (0·14, s.e. 0·10) and lean/bone ratio (0·13, s.e. 0·09).

Phenotypic and genetic correlations among the traits were also estimated. No major incompatibilities were found among the traits. The results are discussed in relation to the genetic improvement of lean meat production in sheep.
Backfat studies in growing pigs 2. A comparison of ultrasound and ruler probe predictors of backfat and eye-muscle measurements in the live pig
Authors: Giles L. R. , Murison R. D. , Wilson B. R.
Published: September 2010

1. Three ultrasonic machines (Sonatest TE/6, Scanoprobe 731 and Scanogram 721) and the ruler probe were compared as techniques for estimating carcass introscope and caliper measurements of P2 backfat thickness on each of 96 pigs. The effect of operator experience was examined with the Sonatest and Scanoprobe machines. Scanogram measurements of P2 backfat and eye-muscle area were evaluated using two methods of restraint (crate and nose rope).

2. The Sonatest was judged to be more precise (increased R2) than the Scanoprobe in predicting P2 backfat depth. Operator experience improved Scanoprobe precision but had little effect with the Sonatest. Ruler probe R2 was intermediate between the Sonatest and Scanoprobe.

3. The Scanogram was the most precise live P2 backfat measurement technique. R2 was not affected by method of pig restraint.
The effects of ambient temperature and air movement on heat loss from the pig
Authors: Close W. H. , Heavens R. P. , Brown D.
Published: September 2010

The heat losses of 24 individually housed pigs (initial body weights 20·0 to 31·8 kg) were measured for periods of 7 days at environmental temperatures of 10, 20 and 30°C. Within each environmental temperature three levels of air movement, 3, 33 and 56cm/s, were applied for a 2- or 3-day period either in an increasing or decreasing order.

Heat loss was dependent on the environmental temperature and level of air movement to which the animals were exposed. The decrease in total thermal insulation at the highest air movement was equivalent to reducing the air-ambient insulation to almost zero. In terms of its thermal effect a 5cm/s increase in wind-speed was equivalent to a 1°C decrease in temperature.

The lower critical temperature increased with increase in air movement from 19° at 3cm/s to 25° and 30°C at 33 and 56cm/s, respectively. Between air movement rates of 33 and 56cm/s, a 1°C decrease in critical temperature resulted from a 5·3cm/s decrease in air movement.

The effect of increasing air movement from 3 to 56cm/s was to increase the animal's maintenance energy requirements from 706 to 881 kJ/kg0·75 per day at 10°C, from 490 to 715 at 20°C and from 517 to 625 at 30°C.
Dietary nitrogen concentration in growing cattle: the effect on growth rate, feed utilization and body composition
Authors: Lindsay J. A. , Davies H. L.
Published: September 2010

Thirty-six British Friesian castrated male cattle (steers) were included in an experiment to measure the response in live-weight gain and body composition to feeding barley-based diets containing increasing levels of formaldehyde-treated soya bean meal. The response was measured between 100 kg and 350 kg or 450 kg live weight. The basal diet of pelleted whole barley and 10% ground oat straw contained 16·6g to 38·5 g nitrogen per kg dry matter. There were no overall differences in live-weight gain or in feed intake. Between 100 kg and 250 kg live weight, live-weight gain increased significantly from 1 08 to 1·24 kg/day when the lowest and highest nitrogen diets respectively were fed (P<0·05). Animals given the highest nitrogen diets also consumed significantly more feed (P<0·05). Conversely, in the subsequent growth period between 250kg and 350kg live weight, live-weight gain decreased from 109 to 0·89 kg/day when the highest nitrogen diet was fed. There were no significant differences in feed intake.

Groups of four animals per treatment were slaughtered at 365 kg and 465 kg fasted live weight. When animals were fed 23·7 g nitrogen per kg dry matter and slaughtered at 365 kg fasted live weight there was significantly more omental fat (P<0·05) and the fat depth at the 12th rib was greater than in animals fed the higher levels of nitrogen. The differences in omental fat weight between the 23·7 g nitrogen and 16·6g nitrogen per kg dry matter diets were not significant. The proportion of crude protein (nitrogen × 6·25) in the boneless 9-10-1 lth rib of animals fed 23·7 g nitrogen per kg dry matter was the lowest of all diets and significantly less than the two highest nitrogen diets (P<0·05). When similar animals were slaughtered at 465kg there was a non-significant trend for omental fat weight and fat depth at the 12th rib to decrease as the nitrogen content of the diet increased.
Effect of monensin supplementation on growth, feed digestibility and utilization in young calves
Authors: Ilan D. , Ben-Asher A. , Holzer Z. , Nitsan Z. , Nir I. , Levy D.
Published: September 2010

Two feeding trials were carried out with Israeli Friesian male calves, commencing at an average age of 7 to 10 days, and covering a suckling period of 30 days followed by a further 90 days. A conventional starter, or one that contained cotton hulls, was used. In each experiment one group of 10 animals served as a control and a similar group was monensin-supplemented. No coccidia were found in the animals. In experiments 1 and 2 monensin supplementation was associated with increased daily gains of 10% and 47% during the suckling period and of 6% and 17% during the next 90 days, but only the differences obtained in experiment 2 were significant. In both experiments, dry-matter intake relative to body weight was higher with monensin supplementation in period 1, but reduced in period 2. The effect of monensin on molar proportions of acetic and propionic acids was smaller than that reported by previous authors for older cattle.

A separate digestibility trial showed that monensin administered to suckling calves, either with milk replacer or directly into the rumen, improved dry-matter digestibility, increased the excretion of amylase, and tended to reduce that of trypsin and chymotrypsin.
A comparison of milk production traits in Friesian × White Fulani crossbred cattle
Authors: Buvanendran V. , Olayiwole M. B. , Piotrowska K. I. , Oyejola B. A.
Published: September 2010

A study was made of the performance of different grades of Friesian × White Fulani crosses using 12 years' records from 1967 to 1978. Milk yield increased progressively with increases in the proportion of Friesian genes. Lactation length also showed a similar trend, with a difference between 1/2 and 7/8 grades of 41 days. Calving intervals averaged approximately 390 days and did not differ among grades. Calf mortality was high, varying from 16 to 29%. The optimal genetic contribution from the Friesian for this environment is considered to be higher than 75 %
A note on the comparative performance of beef steers implanted with the anabolic steroids trenbolone acetate and oestradiol-17β, alone or in combination
Authors: Heitzman R. J. , Gibbons Diana N. , Little W. , Harrison Lynne P.
Published: September 2010

Five groups of six Hereford × Friesian steers, approximately 1 year old and weighing 363 kg at implantation, were individually fed according to body weight and slaughtered 100 days after implantation. Group 1 was sham-implanted subcutaneously in the ear. Group 2 was implanted with 20 mg of the steroid oestradiol-17β group 3 with 140mg of the steroid trenbolone acetate; group 4 with oestradiol-17β in one ear and trenbolone acetate in the other; and group 5 with oestradiol-17β and trenbolone acetate as a single implant in one ear.

Groups 1 to 5 had mean overall live-weight gains (±s.e.) of 0·79, 0·88, 0·89, 0·98 and 1 15±0·067kg/day; mean feed conversion ratios of 9·30, 8·78, 8·45, 8·13 and 6·92 + 0·61; and mean cold carcass weights of 236, 246, 250, 252 and 257 ± 6.4kg, respectively. Oestradiol-17/? reduced omental (P <0·05) and kidney (P <001) fat. The two steroids appeared to produce independent and additive effects except when used together as a single combined implant (group 5), when the effect on live-weight gain was more prolonged. The mean concentrations of oestradiol-17/i in plasma in groups 2, 4 and 5 were greater than in the control group at 28, 28 and 91 days after implantation respectively (P < 0·001). Trenbolone acetate was present in the plasma in groups 3, 4 and 5 throughout the experimental period.
A note on ovulation rate and embryonic survival in D'man ewes
Authors: Lahlou-Kassi A. , Marie M.
Published: September 2010

The elements of prolificacy have been analysed for the D'man sheep, a prolific Moroccan breed, by laparotomy on 38 animals. The average ovulation rate was 2·50 (s.e.0·45); a slight difference was observed between nulliparous and multiparous ewes due to high simultaneous activity by both ovaries in the latter group. Embryonic survival (42% overall) was 94% (87 to 100%) for multiparous and 44% (36 to 52%) for the nulliparous ewes at one ovulation, decreasing with increasing numbers of corpora lutea. The average litter size showed an optimum at four ovulations.
An experimental check on an index combining individual and family measurements
Authors: Avalos E. , Hill W. G.
Published: September 2010

Using a pedigreed population ofDrosophila melanogaster, various indices of individual and full-sib family information were compared for predicting progeny performance for bristle score. On average, the indices were 14% more accurate than individual performance or family mean taken separately. Index weights computeda priorifrom data solely on the parent's generation gave an index almost as accurate as that computeda posterioriby multiple regression of performance of progeny on parents and parent's full sibs. The value of the index was therefore as predicted from theory.
The effect of departures from lower critical temperature on the group postural behaviour of pigs
Authors: Boon C. R.
Published: September 2010

The postural behaviour of a group of 12 pigs in a pen was studied whilst the air temperature was varied, all physical variables except pig weight being held constant. The air temperature was varied between −4°C and + 5°C of the theoretical lower critical temperature. The range of live weight was from 30kg to 75 kg. An indication of whether the pigs were above or below their lower critical temperature was obtained from the amount of huddling. Pigs of less than 45 kg live weight had a greater tendency to modify their environment by altering their posture. Measurements of floor-area covered showed that pigs over 50 kg live weight occupied an area approximately equal to the recommended minimum whilst smaller pigs occupied up to 20% less area than that recommended, depending upon the temperature: this was due to the tendency of smaller pigs to lie on top of each other when cold.
Systems of concentrate allocation for dairy cattle 3. A comparison of two flat-rate feeding systems at two amounts of concentrates
Authors: Moisey F. R. , Leaver J. D.
Published: September 2010

In a 20-week experiment beginning at week 3 post partum, autumn-calving dairy cows were offered either a flat rate of concentrates in which all the cows received the same daily amount throughout the experiment (G). or a flat rate based on their individual milk yield at 2 weeks post partum (I). Two amounts of concentrates were compared and grass silage was available ad libitum. The amounts of concentrate were 6 kg/day (6) and 12 kg/day (12). In the I treatments the ranges of individual inputs were 4 to 8 and 9 to 15 kg/day for the 6 and 12 kg/day treatments respectively. For treatments 6G, 61, 12G, and 121 respectively, mean milk yields were 25·5, 25·7, 28·9 and 27·6 kg/day; mean live-weight changes +0·05, +0·04, +0·19 and +0·27 kg/day; and mean silage dry-matter intakes 11·1, 11·2, 8·1 and 7·5 kg/day. The differences between systems of allocation were not significant, but differences between amounts of concentrate offered were significant. The system of allocation had no significant effect on milk composition. In the residual period (2 weeks indoors and 19 weeks grazing) there were no significant effects on performance. The mean 305-day milk yields for 6G, 61, 12G and 121 respectively were 6376, 6422, 6720 and 6597 kg.