bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lactation studies with Blackface ewes and their lambs
Authors: Peart J. N. 
Published: March 2009

SUMMARYData collected from mid-pregnancy until the 5th week of lactation were used to select three nearly uniform groups each of nine ewes suckling single lambs. After 4 weeks of lactation, experimental treatments were applied to these selected groups as follows: Group I. Both ewes and lambs fed ad lib.throughout. Group II. Ewes fed ad lib. throughout. Lambs offered one-third the quantity of solid food being consumed by group I lambs. Group III. Food intake of ewes restricted to 9·2 g D.o.M./kg, based on their mid-pregnancy live weights. Lambs fed ad lib. throughout. The effects of these treatments were assessed in terms of milk production, food intakes and live-weight changes of ewes, and the solid food intake and growth rates of lambs. Mean total milk production of ewes of groups I and II remained similar until the 8th lactation week, but during the 8–12 week period milk production of the ewes in group II was 6·17 kg greater than that of ewes in group I. The data suggest this difference was due to a reduced intake of milk by the lambs suckling the ewes in group I during the weaning process. From week 4 the milk yield of group III ewes declined rapidly and though these ewes drew on body reserves for milk production, this process could not sustain milk yields. The average daily live-weight gains of lambs of groups I and III were both significantly greater than that of group II, and the gain of group I lambs was significantly greater than that of group III. All groups of ewes made similar live-weight gains during early lactation and after 4 weeks each group had attained a mean value of about 60 kg. Groups I and II continued to gain weight and during week 12 their respective mean weights were 67 and 65 kg. This difference was not statistically significant. The mean live weight of group III ewes declined rapidly after week 4, reaching a minimum value of 41·5 kg. The mean daily intake of dry matter by ewes of all groups reached a maximum value of about 2·9 kg/ewe in lactation week 3 and declined to about 2·6 kg in week 4. Intakes by ewes in groups I and II were almost identical throughout. During the period of restricted feeding the mean daily intake of group III ewes was 0·58 kg dry matter/ewe. During week 5 the mean daily intakes of solid food dry matter by lambs of groups I, II and III were 44, 32 and 158 g respectively. These increased to 1230, 418 and 1537 g respectively during week 12.
The effects of grinding, supplementation and incubation period on cellulose digestibility in vitro and its relationship with cellulose and organic matter digestibility in vivo
Authors: Wilkins R. J. , Minson D. J. 
Published: March 2009

SUMMARYThe in vitro cellulose digestibility of thirteen cuts of perennial ryegrass, cocksfoot and two varieties of Rhodes grass was determined under different conditions. Cellulose digestibility was increased by increasing the length of the incubation period (1,2 and 6 days), the fineness of grinding of the samples and by addition of a supplement. The effects of fineness of grinding and of supplement were greatest after incubation for 1 day and least after 6 days. Between-run variation in cellulose digestibility was reduced by the supplement and by increasing the length of the incubation period.In a comparison of different methods of predicting in vivo organic matter digestibility the lowest residual standard deviation ( ± 2·29) was with in vitro organic matter digestibility (1 mm screen and incubated with supplement for 2 days). Other residual errors were: in vitro cellulose digestibility ± 2·40, pepsin-soluble organic matter ± 4·93, total available carbohydrate ± 6·39, cellulose ± 6·40 and nitrogen ± 6·46.
Sodium and potassium in pig muscle
Authors: Lawrie R. A. , Pomeroy R. W. 
Published: March 2009

1. The sodium and potassium content of longissimus dorsi (lumbar), psoas major, rectus femoris, triceps (lateral head) and extensor carpi radialis from 6 pigs each at pork, bacon and manufacturing weights were determined: these varied significantly and systematically between muscles and between groups.2. Since the concentration of potassium may differ by at least 30% between muscles, it is concluded that assessment of total muscle mass may be inaccurate if based on the integration ofγ-ray emission from 40K.
Plasma lipids of newborn and adult ruminants and of lambs from birth to weaning
Authors: Leat W. M. F. 
Published: March 2009

The plasma lipid concentrations of newborn lambs, kids and calves and of adult ruminants in 0various physiological states have been reported. In newborn ruminants plasma lipid concentrations were 20–40 % of those found in their dams at parturition.The concentrations of blood lipids have also been estimated in five lambs from birth to weaning at 90 days post partum. The plasma free fatty acid concentrations rose to a maximum at about 45 days post partum and then declined. Possible reasons for this elevation in plasma free fatty acids have been discussed with reference to published data on age changes in lambs of plasma glucose and volatile fatty acid concentrations. The concentration of plasma esterified lipids, mainly phospholipids and cholesterol esters, were very low at birth and rose to reach maximum values at about 20 days post partum before declining to adult values at weaning. These changes have been discussed in relation to diet and rumen development.
High level cereal diets for the growing/finishing pig: II The effect of cereal preparation on the performance of pigs fed diets containing high levels of maize, sorghum and barley
Authors: Lawrence T. L. J. 
Published: March 2009

(1) In a 3×2 factorial experiment sixty Large White type weaner pigs (30 hogs and 30 gilts) were individually and restrictedly fed to 200 lb live weight, six diets (as wet mashes) containing 70 % of either maize, sorghum or barley, each cereal having been processed by either crimping or grinding prior to inclusion in its respective diet. A further two groups of six litter-mate hog pigs per group were used to measured the digestibility of and the nitrogen retention from these six diets at approximately 50, 110 and 190 lb live weight.2. Grinding gave significantly better digestibility than crimping, the ground diets having significantly higher digestible energy contents than the crimped. Between cereals the order of significant decreasing digestible energy content was from maize to sorghum to barley dietary treatments.3. There were no significant differences between cereals in nitrogen retention. Between processing treatments grinding, in terms of g. retained per kg live weight per day, gave a significantly higher value than crimping, at 107 lb live weight.
The effect of cold exposure on wool growth in Scottish Blackface and Merino × Cheviot Sheep
Authors: Slee J. , Ryder M. L. 
Published: March 2009

(1) Nine Scottish Blackface and four Merino × Cheviot ewes were shorn and given an acute cold exposure (at approximately −18 °C) in climate chambers. Individual exposures lasted up to 10 h. Because they were shorn, the sheep subsequently received 4 weeks of mild cold exposure, although kept indoors at an ambient temperature between + 8 °C and +15 °C. Skin and wool samples were taken before and after treatment. Twelve unshorn control ewes were also sampled.(2) Wool production in the Blackface sheep was depressed following the treatment, and this was accounted for by a reduction in both the mean length and the mean diameter of the wool fibres.
The artificial rearing of calves and their growth on grass diets: II. The effect of length of period of feeding cold milk substitute to spring–born calves at pasture
Authors: Lonsdale C. R. , Tayler J. C. 
Published: March 2009

SummaryAn experiment was conducted with 32 spring-born Friesian heifer calves, purchased at an average age of 10 days and fed on cold reconstituted milk substitute at pasture.The milk feeding treatments were 4, 4½, 6½ and 9½ weeks in length, during which time calves consumed an average of 17, 23, 43 and 70 kg dry matter/head of milk substitute respectively. The differences between treatment mean live-weight gains for 10½ weeks of the experiment were highly significant (P < O·OOl): the gains were 0·49, 0·43, 0·64 and 0·78 kg/head/day. There was no significant difference between mean rates of live-weight gain after the tenth week so that the overall treatment—mean live-weight gains for the first 23 weeks, which were 0·65, 0·61, 0·72 and 0·74 kg/head/day, strongly reflected the length of the milk-feeding period and demonstrated no significant compensatory growth by the calves.Twenty of these animals were housed for the subsequent winter period and were returned to pasture for a second grazing season. These were artificially inseminated as their individual live weights reached approximately 320 kg. Animals weaned after only 4 weeks of milk feeding took an average of 9½ weeks longer to reach live weights of 320 kg than these receiving milk for 9½ weeks. There were no marked indications of compensatory growth during this extended period of observations.
Lucerne investigations IV. Effect of germination and seed rates on establishment, mortality and yield of dry matter and protein per acre
Authors: Zaleski A. 
Published: March 2009

The experiment with two trials was carried out to determine the effect of low and high germination and three seed rates of lucerne on the establishment, mortality, and yield of fodder on heavy soil at Cambridge during 1955–8.Highly significant differences were obtained between seed rates and germinations in the number of plants established in the year of sowing. The highest number of plants with thin and short tap roots were in a dense crop at 15 lb./acre and 83% of them were unable to survive the first winter. The highest mortality occurred between sowing and the first harvest year, and the heaviest loss of plants was in the lucerne drilled at 15 lb./acre and lowest at 5 lb./acre. Interaction between germination and seed rates was significant at 1% level in the first and at 5% level in the second count only.The highest differences in yield results were in the first harvest year, when a significantly lower yield was obtained at 5 lb./acre than at 10 or 15 lb./acre, but there was no significant difference in yield between 10 and 15 lb./acre. Lucerne with a high germination at all seed rates gave significantly higher yields than lucerne with a low germination in both trials.
The development of the digestive system of the young animal III. Carbohydrase enzyme development in the young lamb
Authors: Walker D. M. 
Published: March 2009

1. Twelve lambs varying in age from 5 to 35 days in age were slaughtered and their carbohydrate-digesting enzymes studied for any change in activity with increase in age.2. Results are given for the changes in weight of different parts of the digestive organs and their contents, and for the content of NaCl and of total acidity in the abomasum contents.3. Pancreatic and small intestine amylase showed only a slight increase in activity up to 5 weeks of age.4. Lactase and maltase activity in the small intestine were almost constant from 1 week to 5 weeks of age.5. No sucrase activity was measurable in any of the lambs slaughtered in either the small intestine wall or its contents.6. A comparison was made between the carbohydrase activity of the young pig and the lamb.7. Calculations based on the enzyme activities of the tissues showed the theoretical amounts of different carbohydrates which can be digested by lambs and young pigs of varying age groups.8. The results suggest that the young lamb is dependent on the early development of its rumen fauna and flora for the utilization of all other carbohydrates except lactose and glucose.
The development of the digestive system of the young animal IV. Proteolytic enzyme development in the young lamb
Authors: Walker D. M. 
Published: March 2009

1. The digestive organs and contents of twelve lambs, varying in age from 1 to 5 weeks, have been examined for their proteolytic enzyme activity at pH 1·8, 3·5 and 8·5.2. Enzyme activity at 1·8 was present only in the abomasum and its contents.3. All tissues and contents examined were active on haemoglobin at pH 3·5.4. Small intestine contents and pancreas alone were active on azocasein at pH 8·5.5. The majority of tissues and contents increased their proteolytic activity with increase in age. The abomasum wall, however, increased in activity up to 21 days and thereafter decreased, both at pH 1·8 and 3·5.6. Milk-clotting action was measured on abomasum wall and contents. There was an absence of milk clots in the abomasum after 21 days, by which time rumen function had commenced.
An evaluation of Merino wool quality:I. The incidence of coarse fibres in two Australian Merino flocks
Authors: Gallagher J. R. , Yeates N. T. M. 
Published: March 2009

SUMMARYThe fibre length and diameter distributions of the wool of two Merino flocks were evaluated at the neck, mid-side and breech positions, to determine the incidence of fibres which were off-type by reason of excessive length, diameter or possession of a medulla.The ranges of fibre lengths for 10·5–11·0 months' growth were 1·0–17·5 cm. in flock 1 and 1·0–16·5 cm in flock 2. There was no evidence of a bi-modal length distribution in either flock.Fibre diameters at 15–16 months were observed in the range 6–69 μ in flock 1 and 5–52 μ in flock 2. Medullated fibres ranged from 7 to 50 μ in flock 1 and 5–64 μt in flock 2. The incidence of medullation increased in an antero-posterior direction from 0·17 to 0·28% in flock 1 and 0·11 to 0·28% in flock 2.Tests for homogeneity of variance were applied to the estimates of fleece characters in this study as well as estimates of other workers. From these comparisons it is suggested that sheep in the present study are representative of the Merino breed in staple length, fibre diameter and to a lesser extent crimp frequency. The considerable between-animal variation in the observed incidence of medullation should aid in selection against that character with a consequent improvement in wool quality.
Nutritional stress and pre-implantation embryonic mortality in Merino sheep, 1967
Authors: Edey T. N. 
Published: March 2009

SUMMARYThree groups of mature Merino ewes, balanced for body weight and number of ovulations, and totalling 122 animals, received the following treatments subsequent to mating to fertile rams: 1. approximately half maintenance requirements from day 7 to 37; 2. approximately half maintenance requirements from day 7 to 37, plus 10 mg progesterone daily from day 20 to 37; 3. control.The ewes, which were in fat condition, had a mean ovulation rate of 121·3 %; except during the submaintenance period, they gained weight throughout pregnancy.The percentages of ova not represented by lambs at term were 34·7, 46·0 and 42·6 in groups 1 to 3 respectively, the differences being non-significant. Detailed examination of the cycle length data of ewes returning to service suggests that some embryos may have been killed by the submaintenance treatment. Progesterone treatment was not beneficial, nor did its sudden withdrawal on day 37 appear to be detrimental to foetal survival. In a sample of ewes slaughtered on day 37, adrenal gland weights were significantly lower in the two treated groups.Significantly higher losses of ova occurred among twin than among single ovulators and there was some evidence that this was non-random. There was no significant relationship between prenatal mortality and body weight at mating.
The effect of mixing ejaculates from different bulls on motility characteristics and acid production of the spermatozoa in a constant environment
Authors: van Duijn C. 
Published: March 2009

Motility characteristics of bull spermatozoa in mixed ejaculates of different bulls were compared with those of the unmixed samples after 40-to 50-fold dilution with clarified standard egg-yolk—citrate buffer (pH 6·80 ± 0·05 at 37° C., 6·75 ± 0·05 at 22–23° C).Using the photo-electric equipment described by Rikmenspoel (1957b) and by Rikmenspoel & Van Herpen (1957) the mean velocity , the number of spermatozoa passing by a constant spot per time unit n, the total number of spermatozoa moving normally N, the velocity decrease with time ( — d/dt), the half-life period of the number of passages per time unit t½(n) and the half-life period of the total number of spermatozoa moving normally t½(N) were determined. For none of these characteristics was any statistical difference found between the actual results and the expected values based on calculation from the data obtained with the unmixed ejaculates.Acid production was investigated by accurate determination of pH change on incubation of samples diluted ten times with standard egg-yolk—citrate buffer containing 736 mg. added fructose per 100 ml. Again there was no statistical difference between the values found with the mixed semen samples and the expected values.It is concluded that differences observed by other authors must be due to the effect of environmental factors, i.e. to the semmal plasma, for which there is analogous evidence in human sperm physiology.
The post-natal growth of the visceral organs of the lamb Part II. The effect of diet on growth rate, with particular reference to the parts of the alimentary tract
Authors: Wardrop I. D. 
Published: March 2009

1. A study was made of the effects of diet on the growth of the internal organs, and in particular the four stomachs of lambs.2. A total of twenty-three lambs was reared from birth on various diets ranging from all milk to small amounts of milk and roughagead lib.The lambs were slaughtered at various ages and the fresh wet weights of the parts of the alimentary tract and the other internal organs were recorded.3. The growth rates of the four stomachs were influenced by the plane of nutrition, however, the type rather than the plane of nutrition was more important in determining the weights of the stomachs relative to each other and to live weight.4. Lambs fed solely milk from birth had the development of their fore-stomachs retarded at about the level found in the 3-week-old grazing lamb. The abomasums of these lambs were abnormally heavy.5. The rumens and reticulums, which were retarded in their growth by milk feeding, reached normal proportions very quickly once roughage was fed.
Studies of the effects of manuring and season on the yield and chemical composition of the cattle cabbage
Authors: Jones D. J. C. 
Published: March 2009

1. Ten manurial treatments were applied annually to cattle cabbage grown in a six-course rotation for 7 years. Samples were taken in the early winter each year, and from five harvests taken at fortnightly intervals in the last year.2. The dry-matter yields each year closely followed the weather conditions during the growing season. There was no significant fall in the dry-matter yield during the last season. The treatments supplying phosphorus or phosphorus and potassium substantially increased yield, but the application of nitrogen did not.3. The application of nitrogen, potassium or phosphorus increased the levels of these constituents in the crop in practically all cases. The application of phosphorus produced hearted plants which contained significantly less dry matter than the openleavod plants produced in its absence. The levels of ether extract, crude fibre, ash, silica and magnesium wore not significantly affected by the manorial treatments.4. There was little variation in composition as the season advanced except for significant increases in the crude-fibre levels and decreases in the nitrogen-free extractives levels.5. The distribution of the chemical components was investigated in the outer leaves, heart leaves and stem of the plant. This was compared with that in the marrow-stem kales.6. The chemical composition of the cattle cabbage compares fairly closely with that found for the marrow-stem kales grown under similar conditions. It is, however, lower in dry matter, crude fibre, magnesium and chlorine. It may be considered as a replacement for marrow-stem kale as a source of crude protein and all the major minerals except chlorine and possibly magnesium.
Studies on the production of beef from zebu cattle in East Africa I. A description of the Muguga herd
Authors: Lampkin G. H. , Lampkin K. 
Published: March 2009

1. The formation of a herd of Northern Frontier Zebus for genetical research has been described.2. Details are given of the system of mating used and the type of management adopted.Thanks are due to Dr J. W. B. King of the Animal Breeding Research Organization, Edinburgh, for his advice, to Mr M. A. Witcomb for taking the photographs, and to the Directors of the East African Veterinary Research Organization and the East African Agriculture and Forestry Research Organisation for their encouragement.
A comparison of the efficiency of food utilization for egg production of some inbred lines of Brown Leghorn fowls
Authors: Bolton W. 
Published: March 2009

1. The efficiency of food conversion of Brown Leghorn fowls inbred for egg number, or egg size, or egg number and egg size have been compared.2. Comparison between the lines was made for egg numbers, total egg weight and total egg energy. Egg energy was the best measure of production, total egg weight was the next best and egg number the poorest.3. When allowance was made for differences in rates of egg production and egg size, there were no differences in the efficiency of conversion of food to eggs between the lines.4. The standard errors of the means for the analytical data on the twelve replicate mixes of the diet were relatively small, but the range in values was appreciable. The importance of analysing diets in nutrition experiments is stressed, particularly for ‘iso-caloric’ diets.
The influence of aureomycin on chick-rearing results using East African feedingstuffs with special reference to importance of experimental design for accurate statistical analysis
Authors: Trail J. C. M. , Casley D. J. L. 
Published: March 2009

Groups of Rhode Island Red chicks were fed a mash made up from East African feedingstuffs or that diet supplemented with a high level rate of aureomycin—97 g. aureomycin hydrochloride per ton of feedingstuff. The chicks were kept on wire for 8 weeks. The initial improved growth rate of the chicks fed the aureomycin supplemented feedingstuff was not maintained, nor was there any statistical indication that the addition of aureomycin improved the feed conversion rate.Although the mortality rate appeared to be very much lower in the chicks fed the aureomycin supplement, the evidence was too limited to allow this to be attributed solely to the effects of the aureomycin.The experiment illustrates the need for careful design in order that the effect of the factors to be tested may be separated from the effects of other factors contained in the experiment and not confounded with them. Moreover, advanced statistical analysis should be used as an invaluable aid to, but not a substitute for, visual or graphical examination of results, for such examination often yields valuable indications of possible lines of analysis and may avoid the drawing of unjustified conclusions.
Genetic relations between carcass fat and body weight in mice
Authors: Hull P. 
Published: March 2009

Three different stocks of mice were selected for five generations for high body weight at 3, 4½, or 6 weeks of age. Changes in body weight at the three ages and in abdominal fat weight, an index of carcass composition, which occurred in the three lines were compared. It was found that the proportion of fat in the carcasses of the selected animals increased markedly in the lines selected for high 3-week weight, while in the other two lines the proportion remained the same as that in the control line.The theoretical treatment of the genetic relationship between body weights at different ages and between body weight and abdominal fat was reasonably adequate in accounting for the correlated responses actually observed.