bluuebunny/crossref_metadata_2025 huggingface dataset:
A note on the effect of supplementation of yeast culture (Saccharomyces cerevisiae plus growth medium) in the diet of buffaloes on milk yield and composition
Authors: Kumar U. , Sareen V. K. , Singh S.
Published: September 2010

Effect of live yeast culture (Saccharomyces cerevisiae plus growth medium) inclusion in the diet of buffaloes (Bubalus bubalis) on milk yield and its composition was examined. Twenty buffaloes (Murrah breed) having an average daily milk yield of 8 to 10 I and in their early lactation stage were divided into two equal groups. The control group was given a basal production diet consisting of 35 to 40 kg green berseem and concentrate mixture (0·5 kg/kg milk produced) per day per animal and the yeast supplemented group the above diet supplemented with 10 g yeast culture (YC, 5 × 109 c.f.u. Saccharomyces cerevisiae strain 1026 per g). The feeding continued for 10 weeks and during this period milk samples collected at weekly intervals and milk yield recorded daily. During this period, average daily milk yield was increased by proportionately 0·135 and fat-corrected milk yield by 0·185 by inclusion of YC. Fat, protein, lactose and total solids in milk increased proportionately by 0·039, 0·051, 0·030 and 0·034 respectively. The corresponding proportional increases in the quantity of these constituents secreted in milk (kg/day) were 0·237, 0·200, 0·200 and 0·204.
Pancreatic insulin responses to exogenous glucose in Friesian heifers of low or high genetic merit for milk-fat yield
Authors: Xing G. Q. , Mackenzie D. D. S. , McCutcheon S. N. , Wickham B. W.
Published: September 2010

Two studies were conducted to examine the effects of selection for milk-fat yield on pancreatic responses to exogenous glucose, as measured by circulating insulin concentrations following an intravenous glucose load, in heifer calves. The first study involved 6-month-old Friesian heifers, eight each from the Massey University high breeding index (HBI) and low breeding index (LBI) lines. Average breeding indices (BI) for milk-fat yield of the calves based on ancestry BI were 136 (s.d. 2) and 112 (s.d. 2), respectively. Oestrous cycling of the heifers was controlled by intravaginal insertion of progesterone-impregnated controlled internal drug-releasing devices (CIDRs). Challenges of glucose (0, 75, 150 and 300 mg/kg live weight) and insulin (0, 0·1, 1, and 10 fig/kg live weight) were administered via indwelling jugular cannulas and were followed by serial blood sampling to measure responses. Plasma insulin concentrations immediately following the glucose challenge were significantly (P < 0·05) greater in HBI than in LBI heifers, peak insulin concentrations (above baseline) in the HBI group being approximately twice those in the LBI group. Plasma glucose concentrations were marginally lower in HBI heifers, probably due to the secondary effect of the relatively greater hyperinsulinaemia in this group. Although the exogenous insulin challenge significantly reduced circulating glucose concentrations in all heifers, there was no difference between the lines in the magnitude of insulin-induced hypoglycaemia.

The second study was designed to determine whether insulin responses to an exogenous glucose load were influenced by stage of the oestrous cycle in heifers of the two lines. In this study, eight yearling HBI heifers and eight LBI heifers (with BI of 135 (s.d. 4) and 111 (s.d. 1) respectively) were administered an intravenous glucose load (150 mg/kg live weight) on tivo occasions, the first being after 17 days of CIDR treatment (simulating the luteal phase of the oestrous cycle) and the second 46 h after withdrawal of the CIDRs (when the heifers were expected to be in oestrus). HBI heifers again showed significantly greater circulating insulin concentrations than LBI heifers following the glucose challenge but the magnitude of this effect was not influenced by time relative to CIDR withdrawal. It is concluded that heifers selected for high milk-fat yield have an increased pancreatic response to exogenous glucose which is apparently independent of the stage of the oestrous cycle. This difference may provide a useful means of identifying heifers of superior genetic merit for milk-fat production prior to their first lactation.
Decision rules and variance of response in breeding schemes
Authors: Woolliams J. A. , Meuwissen T. H. E.
Published: September 2010

Selection decisions in breeding schemes can involve choices between candidates evaluated to different accuracies. A Bayesian framework is put forward for choosing among candidates, and it is shown that attaching loss functions for estimation errors makes this process different from selecting upon best linear unbiased predictions alone. Examples are given using both linear and quadratic loss to show that when estimation errors are penalized, the selection process tends to select more unrelated and more accurately evaluated individuals. In a dairy cattle breeding scheme response was only slightly lower than that from selection on expected breeding values but with a much reduced coefficient of variation. However, if prediction errors are preferred, with the hope of selecting individuals whose breeding value are higher than expected, extra genetic progress could be obtained by favouring the selection of individuals with low accuracy. This requires consideration of more than a single generation.

With discrete generations and equal measurements on candidates the decision framework was shown to be equivalent to a single quadratic restriction on the selection scores of parents in the previous generation.

A framework based on Bayes decision theory could be simply applied to produce a flexible means for producers to select according to their individual risk preferences.
Response surface analyses of the effects of dietary protein, fat and carbohydrate on feeding and growth pattern in mice from weaning to maturity
Authors: Toyomizu M. , Kimura S. , Tomita Y.
Published: September 2010

Responses of gross energy intake and body weight of mice from weaning to maturity to dietary composition of energy-yielding nutrients were studied. Twenty-four groups of ddY male mice were fed for 70 days purified diets with a range of 0·08 to 0·75 protein, 0 to 0·92 fat and 0 to 0·92 carbohydrate concentration, calculated on a gross energy basis. Food intake and body weight data in each group were analysed by non-linear regression to obtain values of the parameters in the feeding and growth equation of Parks (1982). Prediction equations for these parameters were obtained with mixture model forms as a function of dietary protein, fat and carbohydrate. These equations for the parameters were then used to construct the response surfaces of body weight and growth rate at a given time on a triangular graph. The response surfaces of body weight at any time were convex, peak positions of which shifted from 043 protein and 0·29 fat at 10 days to 0·36 protein and 0·52 fat at 70 days. The configuration of response surfaces of growth rate (dW/dt) to the three components depends on feeding periods and at the longer periods of feeding the convex configuration of the surfaces became planar. The response surfaces of food efficiency (dW/dF) at any age were almost parallel to those of dW/dt, whereas a parallelism was observed between response surfaces of dW/dt and dF/dt only in young animals. These results suggested that the responses of body weight in young animals to dietary composition of energy-yielding nutrients depended on those of daily energy intake as well as food efficiency, but that those in older animals were affected by food efficiency only.
Body size and conformation in identical twin cattle
Authors: Taylor C. S. , Rollins W. C.
Published: September 2010

The variation and covariation of 12 linear body measurements within 60 pairs of monozygotic twin heifers is analysed in terms of a twin's mean size over a two-year period.

Possibly all the covariation, and two thirds, on average, of the variation can be accounted for by a single factor common to all the measurements.

Interpretation of this factor shows that a twin is a more or less proportional replicate of its identical co-twin. This proportionality, however, is somewhat distorted because of relatively greater differences in the later maturing body parts.

Finally it is shown that the predominant differences in both size and shape can simultaneously be described as twin lagging behind identical co-twin by 0±11·8 days' growth.
A comparison of two methods of beef production with Sussex-Ayrshire crosses
Authors: White N. , Holmes W.
Published: September 2010

Two groups of autumn born Sussex-Ayrshire cross cattle balanced for sex were raised from about 400 lb. live-weight to slaughter either on (A) a system based on summer grazing and winter feeding on silage, hay and limited barley or (B) on an indoor system based entirely on concentrates and hay.

Group A produced carcasses which averaged 531 lb. in 616 days with a higher muscle content than Group B whose carcasses weighed 496 lb. after 528 days. Steers grew significantly faster than heifers on both treatments. Maturation of Group A was delayed by scarcity of pasture in September.

From feed intakes, including direct estimates of feed intake on pasture, it was calculated that despite the check suffered by Group A, S.E. per lb. of gain was similar on both treatments and better for steers than heifers.

Since the cost per unit of feed was lower for Group A this group showed the higher margin over direct costs.
Intensive beef production 3. Performance of Friesian steers given low-fibre diets
Authors: Preston T. R. , Aitken J. N. , Whitelaw F. G. , Macdearmid A. , Philip Euphemia B. , MacLeod N. A.
Published: September 2010

Two groups of twelve-week-old Friesian steer calves were self-fed to a slaughter weight of 400 kg. on diets composed solely of either 85% rolled barley or ground maize and 15% of a supplement providing additionalprotein, calcium, phosphorus, iron, copper, cobalt, salt and vitamin A and vitamin D.

There were no health problems on the barley diet, but five of the 15 cattle given maize died from bloat.

Surviving animals on the maize diet took 344 days to reach a carcass weight of 231 kg.; comparable data for the barley-fed cattle were 362 days and 222 kg. The tenth rib cuts from the carcasses of cattle given maize contained significantly more fat and less water and ash than comparable cuts from the barley animals. Feed conversion ratio on the barley diet was 4·76.

A comparison between the Friesian steers in the present trials and others given a lower energy diet containing ground roughage showed that with increasing concentration of the ration there was an increase in rate of gain, killing-out percentage and content of ether extract in the tenth rib cut.
A note on the prediction of muscular tissue weight in sides of beef
Authors: Harrington G. , King J. W. B.
Published: September 2010

Callow (1962) examined methods of predicting the tissue content of sides of beef carcasses from the result of dissecting various joints, reaching the conclusion that no short cuts were possible and that dissection of the whole side was necessary. An empirical rule, suggested by Professor D. M. S. Watson, that one-third of the live-weight of beef animals is muscular tissue, was found to give a more precise estimate of the muscular tissue in a carcass than the weights of muscular tissue dissected from any individual joint. Such an assumption, that all animals have an equal proportion of muscular tissue per unit of live-weight, would be of no value in differentiating between lean and fat animals when slaughtered at a constant live-weight as is commonly done, for example, at the end of progeny tests.
Superovulation and fertility in the pig
Authors: Hunter R. H. F.
Published: September 2010

1. The effects of gonadotrophins administered during the follicular phase of the oestrous cycle were studied in forty gilts; these were purebred Large White or Large White crosses weighing from 200-275 lb.

2. Superovulation was induced by a subcutaneous injection of PMS; half of the animals received in addition an intramuscular injection of LH.

3. All animals which received gonadotrophins exhibited normal oestrous behaviour and only four of the gilts failed to come into oestrus by Day 21 of the cycle.

4. A relationship has been established between the PMS dose and the mean ovarian response.

5. An injection of LH was not essential for ovulation after treatment with PMS. Similarly, it had no significant effect on ovarian response.

6. Egg recovery was 75% in the group of animals that exhibited fertility. Of these eggs, 93% were fertilised and undergoing cleavage.
Associations between serum transferrin polymorphism and disturbed segregation ratios in Welsh Mountain sheep
Authors: Khattab A. G. H. , Watson J. H. , Axford R. F. E.
Published: September 2010

Six serum transferrins have been found amongst 1,030 sheep in a Welsh Mountain sheep flock, apparently produced by six genes segregating as alleles at a single locus. All 21 possible phenotypes have been found.

The genes are designated TfA, TfB, Tfc, TfD, TfE and Tfp, TfA producing the fastest, and Tfp, the slowest migrating component. TfE and Tfp are at a much lower frequency (0·01 to 0·06) than the remaining genes (0·2 to 0·3) and Tfp may represent a fifteenth allele at this locus.

A comparison of observed phenotype frequencies with those expected under random mating, showed that a marked disturbance in segregation existed, with homozygous TfCC animals in consistent excess and a marked shortage of heterozygous TfBC and TfCD animals. Variation amongst remaining phenotypes appeared to be at random. However, incompatibility with the Tfc gene also extended to matings including Tfp. Examination of 282 matings confirmed that the effect of the Tfc gene favours maternal-foetal incompatibility as a cause of disturbed segregation, rather than selective fertilisation. However, reciprocal mating data were not available.
A note on formalin-treated skim milk for sucking pigs
Authors: Barber R. S. , Braude R. , Mitchell K. G.
Published: September 2010

In 1956 the authors showed that formalin could be satisfactorily used for the preservation of skim milk subsequently given to growing pigs from weaning to slaughter (Barber, Braude and Mitchell, 1956). Since then a large proportion of the skim milk used by pig producers in this country has had formalin added to it. No evidence from controlled experiments was hitherto available concerning the value of formalin-treated skim milk for the sucking pig, and it was for this purpose that the experiment reported was carried out.
A note on birth weight and gestation length of calves from left and from right uterine horns
Authors: Hancock J. L. , Purser A. F.
Published: September 2010

Foote, Tyler and Casida (1959) found that the birth weight of Holstein calves from the right horn was significantly heavier than that of calves from the left horn but found no significant effect of side on gestation length. In a further study Foote, Hauser and Casida (1960) found no effect of side of pregnancy on either birth weight or gestation length in an analysis of 128 gestations among Angus and Shorthorn cows. They did find, however, a significant interaction of breed and side of pregnancy on gestation length.
The effect of parenterally administered iron upon outdoor-reared piglets
Authors: Walker Elizabeth A. , Taylor J. H.
Published: September 2010

1. An experiment is described in which 194 pairs of piglets on 10 commercial farms were reared out of doors with access to soil, either on free range or in field pens. One piglet from each pair received 200 mg. of iron as a parenterally administered iron dextrin complex. The soil type and the iron content of the soil were determined on each farm.

2. During the first 8 weeks of life, the treated piglets showed a small but significant positive growth response of 1–2 lb. (3·0%). The response was greater (2·1 lb.) in piglets reared in field pens, but was non-significant in those reared on free range.

3. Differences in blood haemoglobin levels, mortality and the incidence of runt piglets were not significant.

4. Total body iron increased during the first 3 weeks of life by a mean of 339 mg., of which approximately 295 mg. appeared to be derived from the soil.
The nutrition of the early-weaned calf VIII. The effect on nitrogen retention of diets containing different levels of fish meal
Authors: Preston T. R. , Whitelaw F. G. , MacLeod N. A. , Philip Euphemia B.
Published: September 2010

1. All-concentrate diets containing four different levels of Peruvian (anchovy) fish meal and varying in crude protein content from 14·8% to 21·7% in dry matter were given ad libitum to 8 early-weaned Friesian calves over a live-weight range of 60–100 kg.

2. Nitrogen retention was significantly higher on diets containing 21·7% and 19·4% crude protein in dry matter than on diets with 16·8% and 14·8% crude protein. Nitrogen retention as a percentage of dietary intake appeared to be less on the diet with 21·7% crude protein in dry matter than on the other diets.

3. From these data it was calculated that the digestible crude protein requirement for a calf of 82 kg. live-weight gaining at 909 g. daily is between 270 and 340 g.
The effect of three suckling regimes on the lactation performance of Cyprus fat-tailed, Chios and Awassi sheep and the growth rate of the lambs
Authors: Lawlor M. J. , Louca A. , Mavrogenis A.
Published: September 2010

Ninety-nine ewes, 33 from each of the Cyprus fat-tailed, Chios and Awassi breeds, were used to compare the effects of three suckling regimes on lactation. These consisted of weaning the lambs at birth (W0), 2 days (W2) and 35 days (W35). The 35-day, 150-day and total milk yields, as well as lactation length, were measured for each group. The lambs weaned from the ewes at birth and 2 days were reared on ewe-milk replacer. The growth rate of these lambs was compared with that of the lambs being suckled by their dams, before and after weaning.

In all cases the milk yields of the Chios and Awassi breeds of sheep were significantly higher (P<0·01) than those of the Cyprus fat-tailed. Within each breed the 35-day milk yields of the ewes suckling one lamb were significantly higher (P<0·01) than those of the ewes on the W0 or W2 treatments, which themselves did not differ significantly. While the 150-day milk yields of the W35 treatment were significantly higher than those of the W0 or W2 treatments, the differences between suckling regimes in terms of total milk yield and lactation length were not significant. It is concluded that differences in milk yield obtained on different suckling regimes are attributable solely to the length of time that the lambs are suckled by their dams.

Prior to weaning the growth rate of the lambs given the ewe-milk replacer was significantly lower than that of the lambs suckled by their dams. There were no differences in the growth rates of these groups of lambs when both were fattened on a creep feed after weaning.
The effect of low ambient temperatures on the energy metabolism of sows
Authors: Holmes C. W. , McLean N. R.
Published: September 2010

1. The heat production of four sows, approximately 17 months old at the start of the experiment, was measured at five ambient temperatures from 23° to 6°C. Food intake was controlled at different levels for different sows; one sow conceived during the experiment.

2. Heat production increased consistently as temperature decreased from 23° to 6°C; the relative effect on heat production of exposure to low temperatures was greater the lower the level of feeding.

3. Estimated values for whole body conductance decreased as ambient temperature decreased to minimum values of 73 to 77 kcal/m2. day. °C for three sows and 87 kcal/m2. day.°C for the fourth sow, which had a considerably thinner backfat than the others.

4. Estimated values for lower critical temperature varied from 10° to 20°C, with the lower values associated generally with the higher levels of feeding; nevertheless heat production was consistently lower at 23°C than at 18°C.

5. Differences in level of feeding were generally associated with differences in live weight, and it was difficult to obtain reliable estimates of metabolizable energy requirements for maintenance and of net efficiency of utilization of metabolizable energy above maintenance; however analysis on the basis of live weight0·75 produced values of 92 kcal/kg0·75 per day at 23°C and 106 kcal/kg0·75 per day at 18°C for maintenance and between 67 and 75% for the efficiency of utilization above maintenance.
A note on the effect of the presence of rams upon the amount of luteinizing hormone in the blood of ewes
Authors: Chesworth J. M. , Tait A.
Published: September 2010

The effect of the presence of rams upon the blood LH levels of ewes just at the start of the breeding season has been studied. It was found that there was a large and sudden increase in LH levels of ewes exposed to rams when compared to a control group. There were also small but non-significant effects on the mean date of the start of the breeding season and upon the number of lambs born.
A note on the prediction of carcass composition in beef cattle
Authors: Hinks C. E. , Prescott J. H. D.
Published: September 2010

Selected sample joints from the right sides of twelve 18-month-old Friesian steers were used to compare their accuracy in predicting carcass composition. Results indicated that whilst the shin joint proved the more accurate predictor of carcass muscle and bone contents, the loin (ribs 11 to 13) or foreloin (ribs 9 to 10) proved more useful in predicting total carcass composition, provided carcass weight was included as an additional variate.
A note on the reproductive activity of Hampshire and Suffolk ewes outside the breeding season
Authors: Bellinger L. L. , Mendel V. E.
Published: September 2010

The present study investigated the intensity of the anoestrous period in 36 Hampshire and Suffolk ewes as influenced by the photoperiod and the presence of the ram. The study began on 4 April and terminated on 11 June. Ewes kept under natural light in the absence of the ram (Group I) exhibited a limited amount of ovarian activity as determined by cervical smear. Ewes kept under natural light, but in the presence of a ram (Group II) showed an increased amount of cycling (P < 0·05) when compared to that in Group I. Two ewes from Group II mated during the so-called anoestrous period and subse-quently lambed. Ten of 12 ewes, subjected to a decreased photoperiod (Group HI), increased ovarian activity within a few days of light reduction. Five ewes in this group lambed.
A note on the effect of bovine somatotrophic hormone on wool production in growing lambs
Authors: Reklewska Barbara
Published: September 2010

In two experiments carried out on 36 crossbred growing lambs the effect of purified bovine somatotrophic hormone (STH) on wool production and some qualitative fleece characters was studied. Food intake during and after the hormonal treatment was also examined. STH, injected in a dose of 1 mg/kg of body weight in 10- or 15-day intervals to growing lambs from 2 to 100 days of age, increased fleece weight significantly. This increase was accompanied by considerably higher daily food intake both during the hormonal treatment and 15 weeks after cessation of STH injections. No significant effect of STH on qualitative fleece characters was found.
Genetic variation in a line of mice selected to its limit for high body weight
Authors: Al-Murrani W. K. , Roberts R. C.
Published: September 2010

A line of mice, at its limit to selection for high body weight did not decline in performance over 11 generations of random mating, neither did it respond when selection was renewed. The experiment tested a method of improving body weight by a scheme which had earlier increased litter size under similar circumstances. The scheme was to derive partially inbred lines from the plateaued line, to select during inbreeding and, finally, to cross the best inbreds. Body weight was not increased, but the study allowed further examination of the residual genetic variance in the line.

During inbreeding, the inbred lines became clearly differentiated in body weight, proving that loci controlling body weight had not become fixed. There was also a significant response to selection for a lower body weight during inbreeding. The pattern of results suggested the segregation of recessive genes, detrimental to high body weight but which selection had become inefficient at removing. A genetic model compatible with the results accommodated several such recessives, perhaps as many as 10, each with an effect of about two-thirds of a standard deviation (or some equivalent combination of gene number and effect), and at frequencies of around 0·2. Nevertheless, the total improvement in body weight to be gained by their elimination was only half a gram, or less than 2 %. Thus, substantial genetic effects can occur at individual loci despite trivially low heritabilities and negligible potential gains.
A note on the effects of monensin on the performance and on rumen metabolites of intact male cattle
Authors: Holzer Z. , Ilan D. , Levy D.
Published: September 2010

Two groups of 14 intact male weanling beef breed calves were each fed 1·45 kg oat hay daily and concentrates ad libitum, in a 158-day feeding trial. Group ‘a’ received 35 p.p.m. monensin in the concentrate. Group ‘b’ served as a control.

Average daily gain was 1·28 and 1·27 kg, dressing percentage was 58·1 and 58·0, daily intake of concentrate was 8·10 and 8·79 kg and conversion ratio of metabolizable energy into live weight was 74·53 and 81·30 MJ/kg for the monensin and the control group respectively. The percentage of acetic acid in rumen liquor was reduced and that of propionic acid increased very markedly. As a result the acetic acid: propionic acid ratio was reduced from 3·2 in the control group to 1·8 in the monensin group. No peculiarity in the response of intact male cattle to monensin was observed.
Estimation of economic values for selection indices
Authors: Melton Bryan E. , Heady Earl O. , Willham Richard L.
Published: September 2010

A procedure to estimate economic values for use in selection indices is developed. A profit function is specified and a production function that links output to the several inputs developed. The profit function is maximized by equating the partial derivatives of the function with respect to each input to zero and simultaneously solving the resulting system of first-order equations for optimal levels of the variables. These variables include economic values for animal traits and levels of exogenous, producer-supplied inputs. The economic values are then used in a selection index. The resulting index value is therefore determined by the average values of the traits, the available inputs and their prices, output price and the specified production function. The procedure has the flexibility, through varying these parameters, to provide index solutions that are tailored to suit individual production conditions. A numerical example is provided.
Response to different rates of energy intake by Gloucester Old Spot and Large White boars and gilts given the same total feed allowance
Authors: Wood J. D. , Lodge G. A. , Lister D.
Published: September 2010

Sixty pigs, equal numbers of boars and gilts of the two breeds Large White (LW) and Gloucester Old Spot (GOS), in litter groups of three, were divided equally between an initial slaughter group and two treatment groups; H, given a diet with 149 g/kg crude protein (CP) at a daily level of 0·1 W0·75; and L, given a diet with 193 g/kg CP at a daily level of 0·075 W0·75. The cumulative total amount of feed given to each pig was the same, 175 kg, but H received more energy per day. All pigs received the same CP per day but L received more CP in total. Pigs started on experiment at 12 weeks of age. The treatments differed mainly in their ability to promote fat deposition: H pigs grew faster than L, due mainly to a greater deposition of fat (as measured by the weight of subcutaneous fat produced) rather than lean (as measured by the weight of hind limb lean produced). H pigs had a poorer feed efficiency than L pigs.

The breeds were similar in most aspects of production and body composition over both treatments but GOS tended to be slower growing and fatter than LW, with shorter carcasses, thicker backfat, and smaller subcutaneous fat-free hind limbs. Boars were faster growing, leaner and more efficient than gilts, with a higher proportion of bone in the subcutaneous fat-free hind limb and a lower muscle: bone ratio (boars 4·74, gilts 5·28).

For several aspects of carcass composition the potential benefits of the lean types (LW and boars) over the fat types (GOS and gilts) were realized on treatment L but not on H. There was a significant breed × treatment interaction for lean content of hind limb: LW had higher values than GOS on L but both breeds were similar on H. Both LW and boars had significantly less subcutaneous fat than GOS and gilts respectively on treatment L but similar amounts on H.
A comparison of four ultrasonic machines (sonatest, scanogram, Ilis Observer and Danscanner) for predicting the body composition of live pigs
Authors: Kempster A. J. , Cuthbertson A. , Owen M. G. , Alliston J. C.
Published: September 2010

Measurements of the m. longissimus and overlying fat at the last rib were taken on the live pig using ultrasonic machines of differing complexity: Sonatest (simple A-mode machine), Scanogram and His Observer (modified linear scanners), and Danscanner (‘real time’ scanner). These measurements were examined as predictors of the corresponding carcass measurements and percentage lean in the carcass.

Sonatest and Scanogram were compared using 143 purebred and crossbred pigs of different types. The analysis was pooled within breed-type and sex. The standard deviation for percentage lean was 3·94. Residual standard deviations for predicting percentage lean from live weight and best fat thickness were 2·72 (Sonatest) and 2·56 (Scanogram). Addition of m. longissimus depth (Sonatest) and m. longissimus area (Scanogram) reduced these to 2·69 and 2·29 respectively. The use of two or more fat measurements provided no extra precision over a single fat measurement.

Scanogram and His Observer were compared using a subset of 38 pigs. Scanogram was a better predictor of percentage lean using a single fat measurement but when a combination of measurements was used, there was little difference between the machines.

Scanogram and Danscanner were compared using a subset of 27 pigs. The standard deviation of percentage lean was 3·57. Residual standard deviations for predicting percentage lean from live weight, best fat depth and m. longissimus area were 2·18 (Scanogram), and 2·03 (Danscanner). Fat areas had similar predictive precision to fat thickness measurements.
The influence of weaning regime on central testing station performance in pigs
Authors: Webb A. J. , King J. W. B.
Published: September 2010

To investigate possible pre-test environmental effects on testing station performance, pigs from a total of 107 litters from two breed types were weaned on one of three treatments: weaning at 3, 5 or 8 weeks of age, with a different creep-feeding regime on each. At 8 to 10 weeks of age, litter groups (usually consisting of two boars, one male castrate and one gilt) were sent to a Meat and Livestock Commission testing station and performance-tested from 27 to 85 kg live weight on twice daily to-appetite feeding.

Weaning treatment significantly affected live weight at 50 days and boar growth rate and feed efficiency on test, but carcass traits were largely unaffected. Boars weaned on the 8-week treatment showed a significant advantage in index score of two-thirds of a standard deviation over those weaned at 3 weeks. A smaller number on the 5-week treatment were intermediate but did not differ significantly from those on the other two. It is concluded that wide variation in the weaning methods of herds sending pigs to a testing station could affect selection decisions. Ways of removing any bias by standardizing weaning methods or by statistical adjustment are discussed.
The effect of plane of nutrition in early lactation on the performance of beef cows
Authors: Lowman B. G. , Edwards R. A. , Somerville S. H. , Jolly G. M.
Published: September 2010

Twenty-one mature autumn-calving Blue Grey cows were divided into three groups for a 3-year change-over experiment, and each group was allocated to one of three planes of nutrition for the first 150 days of lactation during each year. Milk yields were recorded by machine milking twice daily. The three planes of nutrition corresponded to 1·63, 1·21 and 0·89 of the cow's maintenance allowance 12 h post partum. Increasing the plane of nutrition significantly (P<0·05) increased 150-day cumulative milk yield, but had no significant effect on milk composition. The extent of live-weight loss decreased significantly (P<0·001) as plane of nutrition increased and was reflected in cows maintaining better condition, measured as condition score, through the experimental period.

The small 150-day cumulative milk yield response (32·8 kg per additional 10 MJ metabolizable energy and 62 g digestible crude protein/day) demonstrated the limitation of feeding beef cows for increased milk production in comparison with feeding the calf directly. However, the possible relationship between plane of nutrition, live-weight loss and fertility suggests an important limitation of under-feeding cows during the mating period. Within the constraints imposed, the medium treatment (64 MJ metabolizable energy and 516 g digestible crude protein/day) resulted in levels of cow performance similar to those currently recorded in commercial units. One of the major constraints in the present investigation was the high level of body reserves available in the cows at the start of lactation.
Effects of exposure to a hot environment on Friesian and Brahman × Friesian cattle, with some measurements of the effects of exposure to radiant heat
Authors: Holmes C. W. , King C. T. , Sauwa P. E. L.
Published: September 2010

1. Eight calves of each of two breed types, Friesian (Fr) and Brahman × Friesian (FB), were fed ad libitum on one of two diets; the digestibility of the dry matter of the diets was 72% and 63%. Eight calves were kept at 34°C and eight at 17°C. In a second experiment six of the calves previously exposed to 34°C were subjected to daily exposures to a radiant heat load at 32°C air temperature, while fed on the diet of lower digestibility.

2. Rectal temperatures and respiratory rates were higher, and food intakes and growth rates were lower, at 34°C than at 17°C. However there was only a small difference in growth rate between the two temperatures after the effect of temperature on food intake had been removed by regression.

3. At 34°C FB calves had lower rectal temperatures and respiratory rates than Fr calves, and when fed on the diet of higher digestibility FB calves ate more and grew faster than Fr calves at both temperatures; however there were only small corresponding differences between the breed types for calves fed on the diet of lower digestibility at both temperatures.

4. At 34°C FB calves had lighter (weight) hair coats than Fr calves and FB calves had lighter coats at 34°C than at 17°C; the latter difference was not apparent for Fr calves. Nevertheless, neither rectal temperature nor respiratory rate was significantly affected for either breed by removal of the hair coat at 34°C.

5. In the second experiment the rectal temperatures of FB calves increased by smaller amounts during exposure to radiant heat than was the case for Fr calves; FB calves had faster sweating rates than Fr calves during these exposures.
A comparison of incomplete nursing in the sow in two environments
Authors: Whatson T. S. , Bertram J. M.
Published: September 2010

1. Many apparently normal nursings occur in the absence of milk ejection, but little is known about their frequency or causes. The present paper reports an observational study in which the incidence of these incomplete nursings was studied in detail.

2. Nine lactating sows were studied throughout a 5-week lactation in each of two environments. One was a normal commercial farrowing house, and the other a cubicle in which the sow and litter were effectively alone. Extended (3 h) observations were made on each litter at various ages.

3. Twenty-seven per cent of all nursings were found to be incomplete with little difference between the grouped and alone sows. Incomplete nursings often occurred within 40 min of a complete nursing and increased the interval between successive complete nursings. They also occurred most frequently during the 2nd and 3rd weeks post partum.

4. Irrespective of the housing condition the sows initiated the same proportion of all nursings and a similar percentage of these were incomplete.

5. Incomplete nursings appear not to be an artefact caused by crowding many lactating sows together, but they may reflect some form of discomfort of the sow. The problem of real and apparent nursing intervals is discussed.
Relationships among uterine and placental factors in prolific ewes and their relevance to variations in foetal weight
Authors: Rhind S. M. , Robinson J. J. , McDonald I.
Published: September 2010

Observations were made on the distribution of ovulations between the two ovaries, the distribution of foetuses between the two uterine horns, the total numbers of cotyledonary burrs, and the weights and numbers of foetal cotyledons for each foetus in 80 Finnish Landrace × Dorset Horn ewes killed between 50 and 145 days of gestation. While ovulations were randomly distributed between right and left ovaries, viable foetuses were more evenly distributed between right and left uterine horns. Migration of embryos between the horns contributed to this relative balance but early foetal mortality, which increased with ovulation rate, tended to upset it. The mean number of foetal cotyledons per foetus depended on litter size and distribution, and at any fixed litter size was substantially reduced in those ewes with six or more ovulations. Foetal weights were also relatively low in these ewes. The total weight of cotyledons per foetus decreased by about 12% for each increase of one in number of foetuses, as compared with a 20% decrease in number of cotyledons but only a 7 to 11 % decrease in the weight of the individual foetuses. Comparisons between foetuses within the same litter led to similar trends in the ratios of cotyledon numbers, cotyledon weights and foetal weights. It is suggested that the presence of some very small lambs in large litters should not be attributed to maternal under-nutrition in late pregnancy.
A note on annual reproductive rhythm in Marwari sheep of the Rajasthan Desert in India
Authors: Mittal J. P. , Ghosh P. K.
Published: September 2010

Seasonal fluctuations in oestrous activity and live weight were studied in ewes of the Marwari breed indigenous to the Rajasthan Desert in north-western India. Of the ewes examined 80 to 100% were in oestrus every month of the year, indicating thereby the non-seasonality of female reproductive activity in this breed. On average, each ewe exhibited heat 18 times a year. The incidence of silent heats was low (4·2 %). The average length of an oestrous cycle was 17 days, while the actual period of oestrus varied from 24 to 48 h with an average of 36 h. No seasonal effect on these activities could be observed. The maximum and minimum body weights of the animals were recorded during the autumn (October) and summer (June) months respectively. The body weights differed significantly (P<0·05) between months. Sexual activity in these animals is, therefore, apparently not affected by changes in body weight. The continuous nature of oestrous activity in Marwari sheep may be economically exploited by regulating the lambing season according o t the prevailing ecological conditions and market demands, without the use of hormones.
Phenotypic and genetic parameters for lamb weights in a synthetic line of sheep
Authors: Martin T. G. , Sales D. I. , Smith C. , Nicholson D.
Published: September 2010

Data on 2120 lambs produced over 7 years in the Animal Breeding Research Organization synthetic Dam Line (49% Finn, 22% East Friesian, 16 % Border Leicester and 13 % Dorset Horn) were analysed by least squares. The effects of sex, age of dam, year of birth, birthrearing class, and age of lamb on weights at birth and at 4, 8, 12 and 16 weeks of age were all appreciable. However, pooled within-year correction factors should be adequate in adjusting records for selection. Heritability estimates for weights at the five ages ranged from 0·17 to 0·24 by the sire component method and from 0·18 to 0·28 by regression of offspring on dam. Previous reports of differences in heritability in singles and in twins were not confirmed. Estimates of the genetic correlations among the various lamb weights were high (0·62 to 1·04) indicating that selection for weight at one age should result in increased weights at all ages.
A note on the performance of Soay ewes, when mated to Soay and Dorset Down rams, and the growth rate and carcass production of their lambs
Authors: Large R. V.
Published: September 2010

Soay ewes were mated to a Soay or a Dorset Down ram. Live-weight changes of the ewes, birth weights, growth rates and carcass production of the lambs were recorded, and the food consumption of the ewes and lambs was measured. The use of the Dorset Down ram resulted in significantly heavier birth weights, higher growth rates and heavier carcasses. Under conditions of good nutrition the Soay ewes proved to be capable of carrying very high foetal burdens and it was estimated, from lamb live-weight gains, that they produced a large quantity of milk, relative to their size, particularly when crossed with the Dorset Down ram.
Legume silages as supplements to a maize silage plus urea diet for young calves
Authors: Bowden D. M. , Osbourn D. F. , Gill Margaret , Gibbs B. G.
Published: September 2010

Forty British Friesian calves aged approximately 90 days, mean initial live weight 107 kg, were divided into five groups and the animals in each group offered, ad libitum for 84 days, one of five diets based on maize silage. The basal diet of maize silage and 20 g urea/kg dry matter (diet 1) was supplemented with fish meal at 47 g/kg dry matter (diet 2) or with legume silage supplements at 310 g silage dry matter/kg dry matter. The silage supplements were red clover ensiled with formic acid (diet 3), red clover ensiled with formic acid plus formaldehyde at 30 g/kg crude protein (diet 4), or sainfoin ensiled with formic acid (diet 5). Diets 1 to 5 contained 23·7, 28·8, 28·3, 28·3, and 27·1 g total nitrogen/kg dry matter respectively.

The proportion of the total nitrogen insoluble in water, an indicator of the protein in the diet that was likely to escape degradation in the rumen, was 273, 356, 377, 413 and 339 g/kg for diets 1 to 5 respectively. Increasing the proportion of insoluble nitrogen in the diet by including fish meal or formaldehyde-treated red clover silage improved rates of live-weight gain and efficiency of feed conversion. Mean daily intakes of 15·2, 16·2, 16·2, 15·4 and 15·8 g digestible organic matter/kg live weight produced daily live-weight gains of 0·79, 1·05, 0·88, 0·93 and 0·83 kg/head by calves on diets 1 to 5 respectively. Diet 2 produced live-weight gains and gains per kg of digestible organic matter intake that were greater than those for diets 1, 3 or 5 (P<0·05), but not significantly greater than those for diet 4 (P<0·05). Calf live-weight gains were similar and satisfactory on the basal diet (maize silage and urea) and the diets with formic acid-preserved silage of red clover or sainfoin, but poorer than on the diet with 47 g fish meal/kg diet dry matter (P<0·05).
Effect of copper and cobalt treatment on finishing steers
Authors: MacPherson A. , Dixon J.
Published: September 2010

1. An experiment was undertaken with 44 finishing steers (initially of more than 400 kg live weight) into the effects of copper and cobalt treatments.

2. Significant responses to copper treatment of up to 0·41 kg per head per day of live-weight gain were obtained.

3. A different response to copper treatment between Friesian and beef-type (Hereford or Devon) steers reflected not a true breed effect but a difference in initial copper status.

4. Cobalt bullet therapy proved to be ineffective in maintaining normal plasma vitamin B12 concentrations over the course of the experiment although liver cobalt levels were generally adequate.
A note on the digestibility in lambs of whole, dry barley treated with ammonia
Authors: Laksesvela B. , Slagsvold P.
Published: September 2010

Whole, dry barley treated with ammonia (A), whole, untreated barley (WU) or ground barley (G) were fed with hay and a little high protein concentrate to 7 to 11-month-old lambs. Most apparent digestibility coefficients were found to be 3 to 5 units higher in the diet with barley A than in diets with barley WU or G, the differences being significant. Calculation of the digestibility of barley by difference showed that the coefficients were 8 to 10 units higher in barley A than in barley WU or G as regards dry matter and organic matter. Digestion of crude fibre was better in both A and WU than in G. These differences were also significant.
The use of monensin in European pasture cattle
Authors: Wilkinson J. I. D. , Appleby W. G. C. , Shaw D. C. J. , Lebas G. , Pflug R.
Published: September 2010

Monensin increases propionic acid production in the rumen and improves the efficiency of feed conversion in fattening cattle. Trials carried out in the USA showed that 200 mg monensin/head per day was the optimum dose for increasing the rate of live-weight gain in beef cattle at pasture.

Twelve pasture trials, involving a total of 434 beef cattle, were carried out during 1976 and 1977 to assess the efficacy of monensin for grazing cattle under European conditions. Each trial compared a group given 200 mg monensin/head per day in 0·5 to 10 kg of carrier supplement with a negative control group, fed blank supplement. The average initial live-weight was 260 kg and the average trial duration was 119 days. Daily live-weight gains of the control and monensin-treated cattle averaged 0·786 and 0·893 kg/head per day respectively, an advantage of 107g/head per day or 13·7 % in favour of the monensin treatment (P<0·001). The growth-promoting effect of monensin showed no tendency to diminish with time.
Effects of different husbandry systems on milk production of purebred and crossbred sheep
Authors: Mavrogenis A. P. , Louca A.
Published: September 2010

The effects of different husbandry systems on production characters of 616 purebred and crossbred sheep are reported. The Cyprus Fat-tailed (L), Chios (C) and Awassi (A) breeds were evaluated under intensive, semi-intensive and extensive production systems. The performance of crossbred (C × L, A × L and A × C) Cyprus Fat-tailed and Awassi sheep was compared under extensive husbandry conditions. Ewes on the intensive systems produced more milk, fat and protein (P<0·01), but with somewhat lower fat and protein content than those on the extensive or semi-intensive systems. Chios and Awassi ewes were superior to Cyprus Fat-tailed ewes in nearly all traits (P<0·1), but inferior in terms of fat and protein content (P<0·1). Awassi × Chios crossbreds outyielded both purebred and crossbred sheep in terms of milk, fat and protein yield (P<0·1). Lactation number had a significant effect on milk traits. Maximum milk production was obtained at fourth lactation.