bluuebunny/crossref_metadata_2025 huggingface dataset:
The performance of fattening cattle offered barley and grass silage in various proportions either as discrete feeds or as a complete diet
Authors: Petchey A. M. , Broadbent P. J.
Published: September 2010

Seventy-two male castrates (60 British Friesian and 12 Lincoln Red Shorthorn × (Hereford × British Friesian)) were used. The barley was offered either once daily or in a homogenous mix (complete diet) at different proportions of the total dry matter. The diets ranged from silage alone to one of rolled barley plus 1 kg long hay per day. Animals on the complete diet had greater intakes (8·9%) than those offered their barley once daily but this was not reflected in significantly greater daily live-weight gains. Curvilinear regressions were fitted to the data but further investigations with different breeds of cattle and qualities of grass silage will be required before they can be used with any assurance for predictive purposes in advisory situations. When steers were fed on diets with more than 0·40 barley in the total dry matter their intakes declined but their calculated energy (MJ metabolizable energy) intakes remained similar. It is suggested that this finding should be taken into account when diets for cattle are formulated for advisory purposes.
Soya bean meal, crystalline urea, and a urea, mineral and vitamin solution as nitrogen sources for lactating ewes given whole oats
Authors: Bass Jean M. , Fishwick G. , Parkins J. J.
Published: September 2010

Fifty-one ewes with single lambs and 87 ewes suckling twin lambs (mean ewe live weight, 67 kg) were given a basal diet of 1·0kg hay and 1·0kg whole oats, providing approximately 16·7MJ metabolizable energy and lOOg digestible crude protein per day. Three supplements (A, B and C), providing an additional 45 g digestible crude protein, were compared. Supplement A consisted of 40 g of a fully-soluble liquid product (LS) containing urea, (equivalent to 1090g crude protein per kg), minerals and vitamins; B was 16g urea with solid minerals and vitamins; and C was 125g soya bean meal given in substitution for the same amount of whole oats plus solid minerals and vitamins. The growth rate to 6 weeks for single lambs (11 kg) was unaffected by treatment. For twin lambs the growth rates were 7·5kg (LS), 7·1kg (crystalline urea), 7·8kg (soya) and 6·4k g (unsupplemented) (s.e. of mean = 0·31 kg). Ewes with twin lambs given crystalline urea or LS lost more live weight (approximately 1·04kg) than those given soya (6·6kg) over the first 6 weeks of lactation. The maintenance of normal concentrations of calcium and phosphorus in the blood of ewes suggested that the low total intakes of approximately 4·1 g calcium and 4·7 g phosphorus by the ewes were not inadequate.
The effect of breed type and inbreeding on characteristics of the fleece and skin of 12-week-old lambs
Authors: Woolliams J. A. , Wiener G.
Published: September 2010

Sheep of three pure breeds, the Scottish Blackface, South Country Cheviot and Welsh Mountain, and the crosses among these breeds, were inbred mostly by younger-parent offspring matings for three generations. Observations on lambs at 12 weeks of age were weight of fleece per unit area of skin, mean and variance of fibre length, both primary and secondary follicle density, and fibre diameter. The observations were analysed for the effects of inbreeding of the lamb and its dam, breed type, parity, and the sex and birth type of the lamb. Variation in the traits was also analysed for their relationship to lamb's live weight.

Secondary follicle density and the density ratio (Ns/Np) decreased with inbreeding of the lamb. Primary follicle density increased whilst secondary fibre diameter and mean fibre length decreased with inbreeding of the dam. The effects of inbreeding on the density ratio and on secondary fibre diameter were correlated with inbreeding effects on the lamb's 12-week live weight. For other traits inbreeding did not have a clear-cut effect. Heterosis observed in F2 lambs was in general greater than that previously recorded for F1. For mean fibre length and mean fibre diameter the comparison of the crossbred deviations from mid-parent of the F2 and inbred lambs suggested epistatic interactions were involved. The effect of inbreeding crossbreds and inbreeding purebreds was different for secondary follicle density and primary fibre diameter, the two traits most clearly exhibiting heterosis in the F2. Lambs from first parity ewes had finer primary fibres and lighter fleece samples than had lambs from later parities.
Backfat studies in growing pigs 1. Influence of energy intake on growth and carcass measurements at varying live weights
Authors: Giles L. R. , Murison R. D. , Wilson B. R.
Published: September 2010

1. Measurements of digestible energy intake, live growth and carcass measurements were conducted with 96 individually housed pigs (48 male and 48 female) given the same diet at four feeding levels (ad libitum; Agricultural Research Council daily digestible energy intake (C); C–12·5%; and C–25% daily digestible energy intake. The pigs were slaughtered at one of six live weights (45, 60, 75, 90, 105, 120 kg).

2. Prediction equations of average daily live-weight gain and introscope P2 backfat thickness on the hot carcass (hot P2) were developed as functions of average daily digestible energy intake for males and females at varying live weights. The relationships found were 20·8 g live-weight gain per MJ digestible energy intake and 0·81 mm hot P2 backfat thickness per MJ digestible energy intake from 25 to 90 kg live weight.

3. Compared with feeding level C, C –25% produced no difference in feed conversion ratio, reduced shoulder maximum, mid-back and loin minimum backfat thickness by 6–8 mm (14–4%), 4–2 mm (168%) and 4–1 mm (17–5%) respectively (P<0·01) and increased eye-muscle area by 2908mm2 (10·9%).

4. Compared with females, males reached slaughter weight 9·4 days earlier, increased daily live-weight gain by 64g, increased feed conversion ratio by 0·3, had 1·6mm less hot P2 backfat thickness, had less backfat at all mid-line positions and showed no difference in eye-muscle area.
A comparison of defluorinated rock phosphate and dicalcium phosphate, in diets containing either skim milk powder or soya bean meal as the main protein supplement, for early-weaned pigs
Authors: Partridge I. G.
Published: September 2010

Thirty-six pigs were weaned at 21 days of age and were given diets supplemented with either dicalcium phosphate (DCP) or defluorinated rock phosphate (DFP) from 4 weeks of age until slaughter at 50 kg live weight. From 4 to 9 weeks of age the diets contained either skim milk powder (SKIM) or soya bean meal (SOY) as the main protein supplement. The dietary treatments were arranged in a 2 × 2 factorial design. From 9 weeks of age until slaughter, SOY was the only protein supplement used. Four 7-day measurements of phosphorus, calcium and nitrogen balance were made on each pig. Faecal endogenous P was estimated in two pigs per treatment by the 32P dilution method.

There were no significant effects of P supplement on performance or on apparent absorption, true absorption or retention of P. The apparent absorption and retention of Ca were both 0·07 lower with DFP than with DCP in the period from 9 weeks of age to slaughter (P< 0·001).

From 4 to 9 weeks of age there was no effect of protein supplement on performance. From 9 weeks of age to slaughter, when all pigs were given SOY, those which had received SKIM in the previous period grew slightly faster (P<0·05); their growth-rate overall, from 4 weeks of age to slaughter, was also significantly better (P <0·05).

Pigs given SKIM showed a higher apparent absorption of P (P < 0·001) and higher apparent absorption (P<0·01) and retention (P<0·001) of both Ca and N from 4 to 9 weeks of age. Again, there were carry-over effects in the period from 9 weeks of age to slaughter, although the trends observed in the first period were reversed; pigs previously given SKIM showed significantly lower apparent absorption and retention of both P and Ca, and apparent absorption of N, than those previously given SOY.

There were no significant effects of dietary treatments on the ash, Ca or P content of the fourth metacarpal.
Effect of the sire on the subsequent lactation performance in the dam
Authors: Basu S. B. , Tomar S. S.
Published: September 2010

The effects of 18 buffalo sires, used in 2 years of a progeny-testing programme, on the subsequent lactation performances of their mates, were investigated from a study of 685 lactation records. The traits studied were: milk production, lactation length, length of post partum anoestrus, number of services per conception and length of service period (calving to conception). Parity of calving and sire had a significant effect on 305-day milk yield and lactation length of the mates. Between the 2 years, the sires did not differ for any of the traits of their mates. Although the breeding value of the sires, high or low, did not differ significantly, the sires with high breeding value tended to depress the milk production in the subsequent lactation of their mates and vice versa (r= −0·05). The birth weight of the calves significantly affected milk production. It was concluded that all methods of sire evaluation are likely to be biased by the effect of sires.
Value of conformation as an indicator of sheep carcass composition within and between breeds
Authors: Kempster A. J. , Croston D. , Jones D. W.
Published: September 2010

Carcass evaluation data from two breed-comparison trials were used to examine the value of conformation as an indicator of carcass composition when used in addition to carcass weight and different measures of fatness. One trial involved 1478 crossbred lambs out of three ewe types by Border Leicester, Dorset Down, Ile-de-France, North Country Cheviot, Oxford Down, Southdown, Suffolk, Texel and Wensleydale sires. The other trial involved 920 crossbred lambs out of two dam types by Dorset Down, Ile-de-France, Oldenburg, Oxford Down, Suffolk and Texel sires. Each trial extended over 3 years.

Conformation contributed little to the prediction of carcass lean percentage or proportion of lean in the higher-priced joints, although the additional precision was often significant at P<0·01. When conformation was used in association with dissected subcutaneous fat percentage, it was positively associated with carcass lean content; used with a visual assessment of external fat cover on a five-point scale, which provided a less effective control of fatness variation, it tended to be negatively related to carcass lean content.

Conformation was slightly more valuable for the prediction of lean to bone ratio and m. longissimus depth. The addition of sire-breed effect to weight and fat class provided an important increase in the precision of prediction of percentage lean in carcass and lean to bone ratio. Texel progeny had higher lean to bone ratios and more lean in the carcass than progeny of other sire breeds, but they did not have sufficiently high conformation scores to clearly identify this advantage.
A comparison of silages made from red clover/grass, white clover/grass and high nitrogen grass swards for beef production
Authors: Stewart T. A. , McCullough I. I.
Published: September 2010

Silage cut twice annually (June and August) from a tetraploid red clover/grass sward and three times annually (May, July and September) from a low nitrogen (N) and high N perennial ryegrass/white clover sward was fed in proportion to dry-matter yield from each cut, over a 10-week period, each winter for 3 years to castrated male cattle of initial live weight 401 kg in year 1 and 425 kg in years 2 and 3. The silages were supplemented with 0, 1, 2 and 3 kg concentrate per head daily.

Total dry-matter yield from the red clover/grass sward was similar to that from the perennial ryegrass/white clover sward (high N grass) receiving 360 kg N per ha but the digestibility, particularly of first cut material was much lower. Dry-matter production of the low N grass/white clover sward was 0·73 of high N grass sward and produced silages of similar digestibility and fermentation.

Dry-matter intakes by the cattle were higher on the legume-based silages in years when clover made a worthwhile contribution to total yield, but this did not significantly improve utilization or animal performance compared with high N grass silage. Mean daily carcass gain per head on red clover/grass silage was 0·41 kg which was significantly less than the 0·61 kg on white clover/grass silage and 0·59 on high N grass (P < 0·001). Carcass output from red clover/grass silage was 618 kg/ha and 629 kg/ha from white clover/grass, both of which were significantly less than the 863 kg/ha from the high N grass silage (P < 0·001). Dressing proportion was also significantly poorer in animals fed red clover/grass silage compared with the other silage types.
Estimation of carcass leanness in young rams
Authors: Cameron N. D. , Smith C.
Published: September 2010

The accuracy of six methods to estimate carcass leanness in young rams was studied in 36 Texel-Oxford rams, measured at 5 months of age. The rams were slaughtered and dissected. Plasma non-esterified fatty acid and very low density lipoprotein concentrations, sampled before, during and after fasting, showed no relationship with carcass leanness. The same was true for food conversion efficiency measured from 6 to 16 weeks of age, and for measurements taken with the Scanogram ultrasonic machine. The Vetscan and Danscanner ultrasonic machines gave repeatable measurements of fat depth (0·41 and 0·46 respectively). The Vetscan was the best predictor of carcass leanness by proportionally reducing the residual mean square by about 0·20, corresponding to a correlation of −0·45 between ultrasonic fat depth and carcass leanness. Inclusion of average daily gain and ultrasonic fat depth in a selection index would allow appreciable improvements in both traits.
Cassava and tallow in diets for growing pigs
Authors: Walker N.
Published: September 2010

In two experiments 480 and 360 pigs were housed in groups of 10 and given diets containing different proportions of cassava between 35 and 87 kg live weight. The cassava contained 672, 34, 57 and 39 g/kg air dry matter of starch, crude fibre, total ash and insoluble ash respectively. The diets in the first experiment contained 0, 238, 475 or 713 kg cassava per t. In the second experiment the different levels of dietary cassava (0, 150, 300 or 450 kg cassava per t) were combined in a factorial design with different levels of tallow (0, 50 or 100 kg tallow per t). The pigs were given quantities of food calculated to give isoenergy intakes on the assumption that air-dry cassava contained 14·2 MJ digestible energy (DE) per kg. The feeding scale increased with time to give a maximum daily allowance of DE of 31·8 MJ per pig. Relative to each MJ of DE the calculated levels of lysine and of methionine plus cystine in the diets were 0·64 g and 0·39 g respectively.

In both experiments, increasing levels of cassava resulted in significant reductions in growth rate but had no effect on the conversion of food to live weight or on carcass weight. In both experiments, the diets with the highest inclusions of cassava produced pigs with the thickest backfat. The effect was not significant in the second experiment but in the first experiment the differences were significant between diets with the highest and intermediate levels of cassava. There was a significant interaction between cassava and tallow on growth rate with the depression due to high levels of cassava being reduced when 100 kg tallow per t was included in the diet.

The results of these growth experiments suggested that cassava of the type used here was of similar value to barley on an energy basis when used in diets based on barley and soya bean meals.
The feed intake of grazing cattle III. The influence of level of milk yield
Authors: Jones J. G. W. , Drake-Brockman R. M. , Holmes W.
Published: September 2010

1. The feed intakes of 18 Ayrshire cows continuously grazing a timothy-meadow fescue-white clover sward were estimated by the chromic oxide-faecal nitrogen method for two 6-weekly periods, one in 1960 and one in 1961. The cows consisted of (1) 6 lactating cows, 6–7 months post partum (Low yield), (2) 6 lactating cows, 2 months post partum (High yield) and (3) 6 dry cows; their live-weights, milk yields and milk composition were recorded.

2. The mean organic matter digestibility of the herbage consumed in the two experiments was 78·2 and 76·2%. The mean digestible organic matter intakes (DOMI) were 23·3, 24·7 and 17·6 Ib./day for low yield, high yield and dry cows respectively.

3. The mean daily fat-corrected milk (FCM) yields of the low and high yield cows were 29·1 and 34·3 lb. in the first experiment, and 26·8 and 42·8 lb. in the second. The mean live-weights of the lactating groups were 1036 lb. and 1106 lb. in the two experiments and did not differ between yield levels.

4. DOMI was partitioned between maintenance, live-weight gain and FCM yield by regression analysis. Significant partial regression coefficients of DOMI on FCM varying between 0·221 and 0·272 were obtained. It was concluded that milk production accounted for about 0·24 lb. DOMI per lb. FCM.

5. The results are discussed with particular regard to other estimates of the effect of milk production on the DOMI of the grazing cow and to the estimation of the maintenance requirement for DOM by the grazing animal.
Quantitative estimates of lamb carcass composition 1. Sample joints
Authors: Timon V. M. , Bichard Maurice
Published: September 2010

Interrelationships between carcass composition and the composition of 7 different sample joints were studied in 83 purebred Clun Forest lambs slaughtered at approximately 80 lb. live-weight and ranging in carcass weight from 29 to 42 lb. Correlation coefficients between physically separated fat, muscle and bone in the loin and in the carcass were 0·96, 0·93 and 0·84 respectively (P < 0·01). Corresponding correlations for the best-neck (7–12 rib joint) were 0·94, 0·92 and 0·76 (P < 0·01). The leg and shoulder provided the best estimates of carcass bone. The usefulness of predictions of carcass composition is discussed in relation to the maximum probable errors associated with individual and group mean predictions of carcass composition based on sample joints and with reference to the accuracy of these indices under different treatment conditions. The 5% confidence limits on individual predictions based on loin composition were ± 2.22%, ± 2.44% and ± 1.62 % for fat muscle and bone respectively; indicating that this index cannot be relied on to reflect small differences in carcass composition between individual animals.
The evaluation of sires from progeny test data
Authors: Cunningham E. P.
Published: September 2010

The extraction of sire proofs from non-orthogonal field data of the type met with in cattle A.I. populations presents special problems.

A weighted least squares procedure for the estimation of sire effects from data of this kind, cross-classified by sire and herd, is described. Expected Breeding Values computed from these estimates have certain optimum properties. The standard errors of the estimates of the Expected Breeding Values are derived. The method makes it possible to classify the sires into groups before the proofs are computed. This sub-division of the stud could be useful in young sire evaluation and in measuring genetic trends in the proven stud. The computations are readily programmed for a computer, and the assumptions involved in the use of the method are particularly well suited to A.I. progeny field data, especially where an annual draft of young sires is being tested. A worked example is given.
Effects of groundnut meal containing aflatoxin in cattle diets
Authors: Horrocks D. , Burt A. W. A. , Thomas D. C. , Lancaster M. C.
Published: September 2010

1. The effects of including small quantities of groundnut meal heavily contaminated with aflatoxin in the diets of calves and fattening cattle were studied.

2. Inclusion of 4% or 8% of the toxic meal in concentrate diets for early weaned calves significantly depressed live-weight gain and food intake prior to 3 months. The depression in live-weight gain was due to lowered food intake and to impaired food utilisation.

3. Inclusion of 4% to 12% toxic meal in meal mixtures consumed at 12–13 lb. daily for 20 weeks had no effect on the performance of fattening cattle.

4. Enlarged hepatic cell nuclei were found at slaughter in livers from calves which had received toxic meal and the incidence of these slight lesions varied with toxic meal intake. A very small incidence of similar lesions occurred in fat cattle fed on the highest level of toxic meal.

5. Complete exclusion of groundnut meals containing appreciable amounts of aflatoxin from the diets of calves and dairy cows, and its very limited use in diets for store and fattening cattle is recommended.
A comparison of two methods for allocating concentrates to dairy cows according to yield
Authors: Griffiths T. W.
Published: September 2010

An experiment was carried out with 123 pairs of cows located at 11 centres and extending over 3 years, to compare the performance of cows fed at a fixed rate of starch equivalent per gallon with similar cows fed according to an experimental scale, in which the rate of feeding per gallon increased with increasing milk yield.

Records of milk yields and concentrate consumption were made. Feeding according to the experimental scale produced significantly more milk during the first 14 weeks of the lactation. The increase in milk yield for 52 pairs observed over 28 weeks was not significant in either the first 14 or first 28 weeks.

The economic response (lb. milk for each addition lb. starch equivalent for all pairs over 14 weeks was 1·42 and was very near the predicted value. A slightly larger response of 1·64 was obtained from the highest yielding cows. The response over 28 weeks (for 52 pairs only) was 1·30. Considerable variation in this response was found between seasons and between centres.

These results are discussed in terms of the practical application of the feeding scales used and the responses obtained.
Maternal and genetic influences on follicle and fleece development in Lincoln and Welsh Mountain sheep—a study involving egg transfer
Authors: Wiener G. , Slee J.
Published: September 2010

By mean of egg transfer, lambs of a large breed of sheep (Lincoln) were born out of dams of a small breed (Welsh Mountain) and vice versa. One breed was approximately twice the weight of the other. The effects of this contrast in maternal environment upon the development of the wool follicles and upon subsequent wool production are described in this paper. These effects are compared with differences between singles and twins.

Data were obtained from skin and wool samples taken at birth and at 84 days post-partum.

Genetic differences were the largest single source of variation for most of the component characters of the skin and fleece.

Strong maternal influences were in evidence. These were shown to have affected both Lincoln and Welsh lambs in a general (average) way and also to have had different, specific effects on each genotype as shown by genotype-environment interactions. Differences in maternal environment following egg transfer, clearly affected follicle density, primary/secondary follicle ratio, fibre medullation, fibre diameter and fibre length. Wool production was not affected, apparently because reduced follicle density was associated with increased fibre length.

In the comparison between singles and twins the latter appeared to suffer a post-natal rather than a pre-natal restriction of secondary follicle development, and in the absence of extra fibre growth there was reduced wool production at 84 days.
A note on the effect of certain variables on the performance of early-weaned calves
Authors: Lawrence T. L. J. , Pearce J.
Published: September 2010

Although numerous studies on the early weaning system of calf rearing have given information concerning the composition of milk substitutes and concentrate rations which may be used, and the subsequent growth rates which may be expected, few have given information concerning either the relative effects on subsequent growth rate of initial weight, weaning weight, concentrate and hay intakes, or the relationships which exist among these factors themselves.
The nutritive value of separated milk for pigs. I. A comparison of two diets containing separated milk with a standard all-meal diet
Authors: Chamberlain A. G. , Lucas I. A. M.
Published: September 2010

One hundred and forty-four Large White weaner pigs were used in each of two experiments to investigate the nutritive value of liquid separated milk. Two experimental diets, one based on separated milk and barley meal, the other on separated milk, soya bean meal and barley meal were compared with control meals of the type used in the Pig Industry Development Authority's progeny testing stations. The amounts of milk in the experimental diets were adjusted so that the lysine concentrations in the dietary dry matter were similar to those of the control meals. All diets were given according to a restricted scale relating daily dry matter allowance to live weight, to a scale relating digestible energy allowance to live weight and to ‘appetite’. In the first experiment, pigs were slaughtered at 200 lb live weight, in the second at 260 lb live weight.

Pigs given the separated milk and barley meal diet performed similarly to those given the control meals; those given the separated milk, soya bean meal and barley meal diet had better feed conversion efficiencies than control pigs, particularly over the range 200 to 260 lb live weight. Pigs given diets containing milk had higher killing-out percentages and shorter carcasses than those given the control meals. Diet had no statistically significant effect on the percentages of fat and lean in the sides.

The effects of plane of nutrition were demonstrated by the faster rate of gain and poorer carcass quality of pigs fed to ‘appetite’.

It was concluded that the nutritive value of separated milk is explained by its high energy and lysine content. There was no evidence of any unknown beneficial factor in it.
Further studies of the effect of dietary energy content on the voluntary intake of pigs
Authors: Owen J. B. , Ridgman W. J.
Published: September 2010

1. Twenty-seven Large White pigs from three litters were involved in a 33 factorial experiment in which they were given three pelleted diets containing 0, 10% and 20% of dry sawdust during each third of an experimental period ranging from 29·5 to 118 kg live weight. The effects of these treatments on dry-matter intake and rate of growth in each sub-period and on the final carcass quality of the pig were studied.

2. The results confirmed a previous finding that pigs developed a compensatory increase in intake in response to diets containing increasing amounts of sawdust, but that in small pigs this operates very poorly and leads to much retarded growth on the high sawdust diets.

3. The compensatory intake mechanism took some time to develop after the pig had been put on to the sawdust diets, the delay being much longer in the smaller pig. Similarly, when the pigs were returned to high energy diets some time elapsed before intake returned to normal. During this time lag the pigs grew faster, as with compensatory growth, than when they had not previously been subjected to low energy diets.

4. It is concluded that long-term observations must be made in order to investigate the nutrition of pigs fed ad libitum.

5. Although energy intake can be restricted by giving low energy diets for a short period, this does not seem to improve carcass quality.
A note on the management of grazing, non-lactating ewes
Authors: Jordan R. M. , Marten G. C.
Published: September 2010

Weaning lambs at 8 to 10 weeks of age is widely practised in the U.S.A. The practice results in the ewes being dry for relatively long periods and affords an opportunity to reduce feed costs during that time. Jordan and Hanke (1964) maintained non-lactating ewes in drylot on 2 to 2·5 lb of legume hay per ewe daily, and Jordan and Marten (1965) doubled the number of ewe grazing days (carrying capacity) by restricting the time the ewes were permitted to graze per week to about 50% of normal. In neither study was subsequent wool or lamb production reduced.
Haemoglobin and transferrin types of some West African cattle
Authors: Braend M. , Khanna N. D.
Published: September 2010

Haemoglobin (Hb) and transferrin (Tf) types have been studied in the breeds Muturu, N'Dama, Gudali and Red Bororo of Nigeria, West Africa.

The Hb gene frequencies were: Muturu,HbA= 0·72,HbD= 0·28; Gudali,HbA= 0·60,HbB= 0·32,HbC= 0·08; Red Bororo,HbA= 0·54,HbB= 0·44,HbC= 0·02.

Transferrin studies showed six different Tf phenotypes in Muturu their distribution being in agreement with the occurrence of the allelesTfA,TfD1andTfD2. In N'Dama nine different Tf phenotypes were observed and were explained by the allelesTfA,TfD1,TfD2andTfE. In Gudali 15 different Tf phenotypes were found with a distribution in agreement with the occurrence of the allelesTfA,TfB,TfD1,TfD2,TfFandTfE. All alleles in this breed occurred at frequencies above 0.1. In a limited number of Red Bororo cattle nine Tf phenotypes were seen. Their distribution can be explained by the occurrence of the six genes:TfA,TfB,TfD1,TfD2,TfFandTfE.
Urea and cereals as supplements for ruminants offered barley straw
Authors: Kay M. , Andrews R. P. , MacLeod N. A. , Walker T.
Published: September 2010

In three trials, two with suckler cows and one with lambs, supplementary forms of dietary nitrogen and/or energy were added to a basal diet of barley straw offered ad libitum. The nitrogenous supplements appeared to have a small effect on the intake of straw but only when they were available for frequent consumption. The addition of cereals to the diet did not affect the intake or digestibility of the straw but reduced the live-weight losses.
Voluntary consumption of forage by sheep and its relation to the size and shape of particles in the digestive tract
Authors: Troelsen J. E. , Campbell J. B.
Published: September 2010

Two alfalfa varieties and four grass species were harvested for hay at several stages of maturity. Each hay was given to sheep to provide measures of voluntary consumption and digestibility. Digesta samples were obtained from the reticulo-rumen, omasum and abomasum by killing the sheep at the end of the feeding periods.

Sieving analyses of the digesta revealed that the fraction retained by a 0·25-mm sieve provided greater differentiation between experimental treatments than those retained by 0·5-, 1·0- or 2·0-mm sieves. The weight percentage of this fraction was used as a measure of the relative particle size despite its profound dependence on size, shape, density and distribution of individual particles.

The variation in relative particle size of digesta from different sheep fed on the same diet was illustrated by coefficients of variation ranging from 4 to 11%. Four replicates, however, were sufficient to detect numerous differences (P<0·05) between experimental treatments.

Omasal digesta from alfalfa hay had a greater relative particle size than those from the grass hays at comparablematuritystages. This may be attributable to an apparently more compact particle shape observed in the alfalfa digesta, assuming that in a simple physical sieving process the most compact particle passing a given opening will have the greatest mass. It was proposed that digesta particle shape may have greater specific importance than relative particle size for the rate of passage and voluntary intake of coarse roughage.

A direct relationship was observed between voluntary feed consumption and the relative particle size of omasal digesta from different grass hays at similar maturity stages. This was the reverse of that observed between different maturity stages within hay species. It was hypothesized that the former relationship was due mainly to changing mass of the individual particles passing the reticulo-omasal opening, whereas the latter relationship was caused mainly by the particle size distribution.

The relationship between the relative particle size of digesta from the reticulo-rumen and that of digesta from the omasum supports the theory that the reticulo-omasal opening is the site of major obstruction for the passage of coarse roughage through the digestive system of ruminants.
Observations on neonatal changes of body temperature in Blackface lambs
Authors: Griffiths J. G.
Published: September 2010

Studies of rectal temperature changes in Blackface lambs from birth to 24 hr indicated a very limited effect within an ambient temperature range of 28 to 66°F. The rectal temperature of twins at birth was lower than that of singles, but the difference disappeared by 3 hr after birth. Body weight was correlated with rectal temperature at birth only in twins. In both twins and singles there was an elevated level of rectal temperature after birth which was presumably associated with a postnatal rise in metabolic rate similar to that which occurs in other species. It is concluded from the results that heat regulation is completely developed within a short interval of birth.

Changes in body weight at intervals up to 48 hr were small, and body weight was significantly different from that at birth only at 48 hr in single lambs.
A comparative trial of crossbred ewes by Finnish Landrace and other sires
Authors: Donald H. P. , Read J. L. , Russell W. S.
Published: September 2010

1. A comparison lasting 3 years has been made of 5 types of crossbred ewes produced by mating Border Leicester, Clun Forest, Dorset Horn, Finnish Landrace and Tasmanian Merino rams to Scottish Blackface ewes. Data from a total of 576 ewe years became available.

2. In body weight at mating time when they were 7, 19 or 31 months old, the Border Leicester and Dorset Horn crossbred ewes were heaviest, followed by Cluns. Finnish and Merino crossbreds were about 15–20% lighter than the Border Leicester crossbreds.

3. In fleece weight, Finnish crossbreds were lower by about 1·0—1·5 lb relative to Border Leicester crossbreds.

4. In fertility, Finnish crossbreds were highest with 1·5, 2·0 and 2·3 lambs born per ewe lambing at ages 1, 2 and 3 years respectively. The corresponding averages for the combined Border Leicester, Clun and Dorset Horn crossbreds were 1·1, 1·6 and 1·6 and for Merino crossbreds 1·0, 1·1 and 1·2. Numbers weaned were similarly ranked.

5. Lambs out of crossbred ewes showed a sequence of group differences in weight at birth and at weaning corresponding to those shown by their mothers at mating time. The heaviest lambs were produced by Dorset Horn and Border Leicester crossbreds, and the lightest by Merino crossbreds. As a percentage of ewe weight at mating, lamb weight at weaning was highest for the Finnish group.

6. In terms of litter weight at weaning, fitted values for the Merino group were the lowest while those for the Finnish group were the highest. The
other three groups gave similar and intermediate values.
Relationship between milk composition and yield of milk, fat and protein in Red Danish cattle
Authors: Christensen K.
Published: September 2010

The relationships among five traits in dairy cattle (milk yield, fat yield, protein, fat % and protein %) were examined on the original and on a logarithmic scale. The data comprised the records on 5333 Red Danish cows tested at the Danish Progeny Testing Stations during the years 1960–66. None of the heritabilities or the correlations among the variates were altered appreciably by transformation. For the five traits heritability estimates were 0·56, 0·80, 0·65, 0·64 and 0·56, respectively. Phenotypic and genetic correlations among milk yield, fat yield and protein yield were all very high, about 0·95. The correlations between fat % and protein % were about 0·6. The coefficient of variation of a variate proved to be a good approximation of the standard deviation of the transformed variate even for milk, fat and protein yield with coefficients of variation of 17–18%. It was concluded that little is likely to be gained by using index selection for fat yield and protein yield. However, about 90% of the response obtainable by direct selection for fat or protein yield could be obtained merely by selection for milk yield. A large correlated response for protein yield could be obtained by selecting for fat yield.
A note on the seasonal effect on the growth rate of Hereford cross Friesian male calves
Authors: Jobst D. , Wood P. D. P.
Published: September 2010

In reporting on the Charolais importation of 1962, Edwards et al. (1966) noted different average growth rates of calves born at different times of the year: spring born calves for instance were slowest at 1·67 lb/day and autumn born calves fastest at 1–80 lb/day. The Beef Recording Association (1967) has also reported that growth rates for castrated males in commercial intensive cereal feeding beef lots consistently reflected seasonal effects on growth. In both cases the data were derived under conditions which did not permit detailed investigation of seasonal changes in the growth curve.
Genetic aspects of growth and carcass quality in veal calves
Authors: Hinks C. J. M. , Andersen B. Bech
Published: September 2010

Genetic parameters of veal calves were estimated from data on 510 Danish Red male calves by 39 sires.

Heritability estimates for the growth and carcass traits were low, those for body dimensions and dressing percentage high.

Correlations between the growth and carcass traits indicated no genetic incompatibility in selection.

The problem of achieving simultaneous improvement in the dairy, carcass and growth qualities is discussed. It is suggested that the adoption of performance testing for growth and carcass quality prior to the entry of bulls into AI service, followed by progeny testing for milk and fat yields, would provide the best method of genetic improvement.
Cold exposure of Southdown and Welsh Mountain sheep. 1. Effects of breed, plane of nutrition and acclimatization to cold upon resistance to body cooling
Authors: Sykes A. R. , Slee J.
Published: September 2010

1. Twenty-four Southdown and 24 Welsh Mountain year-old female sheep, half on high plane and half on low plane nutrition, were closely shorn and given two short acute cold exposures (−20°C, 4 mph wind) in climate chambers. For two weeks before the first acute exposure half the sheep were kept at a moderately cold temperature (+8°C) and the remainder at a thermoneutral temperature (+30°C). During the next two weeks between acute exposures these temperatures were reversed for each group of sheep.

2. Resistance to body cooling during acute cold exposure was significantly greater after exposure to + 8°C. This was attributed to acclimatization. No further acclimatization resulted from acute cold exposure in addition to chronic moderate cold exposure.

3. Sheep which had been kept at +8°C cooled 33% more slowly than those which had been at + 30°C. High plane sheep cooled 34 % more slowly than low plane sheep. Southdowns cooled 32 % more slowly than Welsh sheep, but the Welsh sheep showed relatively greater acclimatization on low plane nutrition.

4. Compared with Scottish Blackface sheep given similar temperature treatment in an earlier experiment, the Southdowns and Welsh showed less initial cold resistance and less capacity for acclimatization.
Cold Exposure of Southdown and Welsh Mountain Sheep. 3. Changes in plasma calcium, phosphorus, magnesium, sodium and potassium levels
Authors: Sykes A. R. , Field A. C. , Slee J.
Published: September 2010

Southdown and Welsh Mountain female sheep, equal numbers on high and low plane nutrition, were shorn and subjected to two acute cold exposures (−20°C, 4 mph wind) in climate chambers. Before the first exposure the sheep were kept in either a cool (+8°C) or a thermoneutral (+30°C) environment for two weeks. Between exposures these environmental temperatures were reversed within groups. Blood samples were withdrawn at the beginning and end of the two week exposures and on three occasions during acute cold exposure. Plasma analyses of Ca, P, Mg, Na and K were carried out. Exposure to +8°C caused a 12% reduction in plasma Mg levels of all sheep, but had no effect on Ca, Na or K levels. There were breed × temperature interactions with respect to plasma P levels. Acute cold exposure caused reductions in plasma Mg and Ca levels and an increase in plasma P levels of all groups of sheep. Changes in plasma Na and K levels could have been caused by plasma concentration.

Electrolyte levels initially displaced by exposure to +8°C showed no evidence of a return to normality two weeks later. Only for Ca was there evidence that prior exposure to +8°C modified the response to acute cold exposure.
A note on commercial crossing of Bulgarian finewool ewes with rams of English short-wool breeds
Authors: Tomov I.
Published: September 2010

Dobruja Finewool ewes were mated to two rams of each of the Clun Forest, Hampshire, Suffolk and Oxford Down breeds as well as to rams of their own breed. The crossbred and purebred lambs were compared in terms of growth, food consumption and carcass attributes. The crossbred lambs of Hampshire, Suffolk and Oxford Down breeding were superior to the purebred control lambs on all counts while Clun Forest crossbred lambs were superior to controls only in carcass attributes and the time taken to reach slaughter weight but not in efficiency of conversion.
Ammonium salts of fatty acids for milk production 1. The effect of feeding a salt solution containing ammonium acetate on the yield and composition of milk produced by Jersey cows fed hay/concentrate diets
Authors: Prescott J. H. D. , El-Shobokshy A. S. , Armstrong D. G.
Published: September 2010

1. Two experiments have been carried out to study the nutritive value of dilute solutions of fatty acids (consisting mainly of ammonium acetate) when incorporated in the diet of lactating Jersey cows.

The first, a continuous trial, extended over a total of 17 weeks and involved five pairs of cows. One cow in each pair received the treatment and one the control diet. The second trial, of change-over design, involved four pairs of cows; one cow in each pair received one or other of the experimental diets alternately over four 28-day periods.

2. The cows received basic diets comprising hay ad libitum and concentrates regulated according to milk yield. On the control treatment cows received water and a concentrate containing an appropriate percentage of groundnut cake; on treatment cows received a dilute solution of salts and an ‘all-cereal’ concentrate. The treatment provided cows with approximately 30% of their total DCP intake as ammonia-N and with 270 to 310 g of acetate and 43 to 49 g of propionate/day from the salt solution.

3. Solutions of salts have been offered to the cows at various concentrations in the range 0·25 to 2·6% (w/v) as a substitute for drinking water. Nineteen of the 20 cows consumed solutions of 1·4% concentration in normal quantities equivalent to water.

4. Treatment was associated with an appreciable depression in the yield of cows producing 13 to 14 kg of milk per head/day, but had little effect on the yield of cows producing 10 to U kg or less. This result has been discussed with reference to the role of the ammonia-N as a substitute for protein-N.

5. Treatment significantly increased the fat content of the milk produced by these Jersey cows above the high control level of 5·4%. Total milk fat production was also increased. This result has been discussed with reference to the role of acetate in dairy cow diets.
The influence of seasonal variation on fertility and early body growth in sheep
Authors: Land R. B. , Dickinson A. G. , Read J. L.
Published: September 2010

The effect of the time of mating on ewe fertility and subsequent lamb growth was examined in Clun sheep in Scotland. The flock of 249 females was divided into six mating groups, the first was put to a fertile ram on 12 October 1962, the remainder being added at two weekly intervals.

There was a marked decline in the average number of lambs born per female lambing as the time of mating moved from October to December (b = −0·007 per female per day). Other components of fertility were not affected.

The mean birth weight was slightly greater in the later mating groups; however, by the time the lambs were 9 weeks of age, the trend was reversed, the regression of 9-week weight on day of mating being −0·063 lb per day.
A note on correction factors for lamb birth and weaning weights from sheep recording under field conditions
Authors: Robertson K. J.
Published: September 2010

A small scale ewe-recording scheme, involving a minimum of weighing, is described. Results for two years and two breeds have been analysed to produce correction factors in each year for birth type, sex and age of dam in respect of birth weights and weights at 84 days of age derived with and without reference to birth weight. The results suggest that breed differences in correction factors may exist and that differences between years in correction factors may be of minor importance. In standardizing weaning weights to a constant age the influence of birth weight appeared to be relatively unimportant.
Crossbreeding of sheep under semi-arid conditions
Authors: Fahmy M. H. , Galal E. Salah E. , Ghanem Y. S. , Khishin S. S.
Published: September 2010

Data were obtained on 3028 lambs born during five successive years from 1961 to 1966 at Ras El-Hekma Desert Research Station in the Western Coastal Egyptian Desert. Breed groups involved in the study were Hungarian Merino, Syrian Awassi, native Barki sheep, and nine of their crosses. The characters studied were birth weight, weaning and yearling weights, pre- and post-weaning average daily gain and yearling greasy fleece weight. The effects of breed group, year of birth, sex, age of dam and type of birth on these characters were investigated.

The results obtained showed that Barki lambs excelled Merino lambs in all the traits related to body growth. Merino lambs, on the other hand, excelled Barkis in fleece weight. Barki lambs also excelled Awassi lambs in all traits except birth and weaning weights. In all characters except pre-weaning gain, the first cross of Merino and Barki (½M½B) was markedly superior to all the other crosses and pure breeds. The two third-crosses, ⅜ M ⅝ B and ⅝ M ⅜ B, were similar to each other in their productive traits and were slightly inferior to the first cross. The two back-crosses, ¼M¾B and ¾M¼B, were markedly different from each other, the former being better than the latter. The three-eighths Merino group is suggested for developing a new strain of sheep for the semi-arid regions. The effects of the environmental factors on the six characters studied were all highly significant except for the effect of sex on fleece weight and the effects of age of dam and type of birth on growth from weaning to yearling ages. The most important factor affecting the different traits was year of birth. Type of birth and age of dam were important sources of variation only for the characters studied till weaning age, but became of little importance thereafter. The effect of sex was pronounced only on yearling weight.
A note on the implantation of intensively-fed beef cattle with hexoestrol
Authors: Macdearmid A. , Preston T. R.
Published: September 2010

In the first of two experiments, steers which received a single implant of 60 mg hexoestrol grew 24% faster than non-implanted controls and 7% faster than steers given 30 mg. The growth rate of the steers given a single implant of 60 mg did not differ significantly from that of animals implanted twice with 30 mg or 5 times with 15 mg. In the second experiment, steers given 60 mg grew 23% faster than controls and their feed conversion efficiency was 13% better; the hexoestrol treatment resulted in a saving of 131 kg feed per animal. The tenth-rib joints of steers given 60 mg had a higher crude-protein content and lower fat content than those from non-implanted animals.