bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nutritional stress and pre-implantation mortality in Merino sheep, (1964–7). General discussion and conclusions
Authors: Edey T. N. 
Published: March 2009

SUMMARYCollation and re-analysis of the results obtained in separate experiments investigating prenatal mortality in Merino ewes over a period of 4 years have made it possible to draw the following general conclusions:Data from the control groups indicated that in 3 out of 4 years basal prenatal loss averaged approximately 25%, which agrees with a number of other estimates in the literature. Higher losses of ova in 1965 than in the other 3 years could not be partitioned accurately between fertilization failure and prenatal mortality.Submaintenance nutrition apparently caused embryo mortality in 1964, and possibly in 1967, when underfeeding from day 7 to 37 was followed by an unusual number of long cycles; however, there was no evidence of increased mortality in 1965 and 1966.Losses of ova shed as twins were significantly greater than amongst those shed as singles in 1964 and 1967. The higher loss of twin ova was clearly associated with the treated groups in 1964.In each of the 4 years the left ovary produced more ova than the right, and when the 4 years' data were combined, survival of ova shed by the left ovary was significantly better than of those shed by the right. The type of twin ovulation, i.e. whether the two ova came from one ovary or two, had no consistent effect on prenatal mortality.In 3 years there was no significant regression of prenatal mortality on body weight at mating. However, in 1965, when body weights were relatively low, there was a significantly negative regression. It is possible that there is a critical body weight below which poorer prenatal survival can be expected.Ewes which suffered embryonic loss followed by a delayed return to service subsequently conceived less readily than those having a cycle of normal length following fertilization failure or early embryonic death. It is postulated that in some cases this may be because ovulation occurs while resorption is still incomplete. For some ewes having long cycles after embryonic death, anoestrus or removal of the fertile rams precluded subsequent conception in that season. This was an added reason for the season's lambing performance of ‘long cycle’ ewes being much worse than that of ewes re-mated after normal length cycles.
Metabolism of the soluble carbohydrates of grasses in the rumen of the sheep
Authors: Thomas Gwen J. 
Published: March 2009

1. The bacteria and protozoa from the rumen of the sheep have been examined for their invertase activity.2. Washed suspensions of protozoal fractions obtained from the rumen were rich in invertase, and the greater part of the total activity in the rumen could be ascribed to the holotrich protozoa.3. Rumen streptococci capable of fermenting sucrose and fructan were isolated in pure culture. Their invertase was found to be an adaptive enzyme.4. Fermentation of the soluble carbohydrates of grass was studied in an ‘artificial rumen’. The micro-organisms converted 30% of the substrates into storage starch.5. Rumen contents from a grass-fed sheep were twice as active towards grass carbohydrates as those from hay-fed sheep.6. The hay and grass fed to the sheep contained invertase activity.
Some genetic implications of maternal effects—an hypothesis of mammalian growth
Authors: Dickinson A. G. 
Published: March 2009

In a cross-breeding experiment involving all types of matings among Friesian, Ayrshire and Jersey cattle, the effect of maternal size has been investigated, based on various comparisons of reciprocal crosses, using data on weight and body size from birth to 2 years of age. Among the thirteen characters analysed, there was a close relationship at I month old between the relative maturity of the characters and the relative extent of their maternal effects. This relationship showed that the more mature characters were the least affected by the maternal environment. Cross-bred calves out of a mother of the larger breed were larger at birth than the reciprocal crosses but in all cases this difference disappeared during the first year's growth.The early expression of the offspring's genotype for body size depended on whether prenatal growth had been favoured or restricted by the maternal environment within limits. Maternal retardation of growth resulted in neonatal phenotypes closely related to their genetic ranking for mature body size, whereas early expression of the genotype is obscured by lavish prenatal conditions.A mammalian growth model is presented and the results are interpreted in terms of this model. The explanation assumes that temporary advantage is taken, during growth, of variations in the environment, when the latter exceeds a minimal level demanded by the genotype for stable development to normal mature size. This supply and demand hypothesis of growth is discussed in terms of its implications for genetic selection of different types of body characters. The main conclusion is that an understanding of the early environment, particularly the maternal one, may permit selection for some adult characteristics to be carried out at an early age.
Nitrification of urea and its loss through volatilization of ammonia under different soil conditions
Authors: Wahhab A. , Khan Mahmud , Ishaq M. 
Published: March 2009

Nitrification of urea and its loss through the volatilization of NH3were studied under different soil conditions. Under all conditions less urea was nitrified and more time was needed for its nitrification in sandy than in sandy loam soil. Nitrification was favoured at lower concentration of urea, onethird moisture of the moisture-holding capacity and at neutrality or the alkaline pH.Loss of NH3was found to be twice as much from the sandy loam as from the sandy soil. It was also found that half of the total loss occurred during first drying. Loss of NH3from urea was found to be proportional to its concentration. The loss increased with the increase in soil moisture and temperature; but it decreased with the decrease in pH on the acid side and the increase in depth of its placement.
Cytological characteristics and fertilizing capacity of bull spermatozoa
Authors: Campbell R. C. , Hancock J. L. , Shaw I. G. 
Published: March 2009

1. Two methods were used to estimate the frequencies of nine morphological classes of spermatozoa in 257 ejaculates from one Guernsey, five Friesian and seven Hereford bulls at an insemination centre. In nigrosin-eosin stained preparations and in fixed wet preparations the respective mean frequencies (%) were: malformed heads, 1·08 and 0·98; malformed middle pieces, 0·88 and 0·89; bent tails, 3·92 and 4·56; coiled tails, 0·60 and 0·43; free heads, 3·72 and 2·63; free tails, 1·79 and 1·85; neck beads, 0·87 and 0·93; middle-piece beads, 4·91 and 6·83.2. There were close correlations between the two sets of measurements, but the differences of means were significant for free heads, bent tails, coiled tails, neck beads and middle-piece beads.3. The mean percentage of dead (eosinophil) spermatozoa was 21·0.4. The variations in the frequencies of each morphological class and of dead spermatozoa were divided within and between samples, ejaculates, bulls and breeds. The frequencies of all classes differed significantly between ejaculates within bulls; all but broken necks differed between bulls within breeds, and the Friesian and Hereford bulls differed in the frequencies of malformed heads, free heads, malformed middle pieces, free tails, neck beads and dead spermatozoa. The frequencies of bent tails, coiled tails and dead spermatozoa declined significantly with order of ejaculate.5. The interrelationships of the frequencies of each class were examined. Two new methods used to measure the dead-sperm content of semen were shown to give results significantly correlated with those obtained by the conventional staining method and with motility ratings.6. The interrelationships of measurements of the individual characteristics and conception rate were examined. Within-bull variations in conception rate showed a significant positive correlation (P < 0·05) with the frequencies of malformed heads and free heads. The between bull variation in conception rate showed a negative correlation with the frequency of neck beads (P < 0·05).
Dietary effects on beef composition: I. Quantitative and qualitative carcass traits
Authors: Garrigus R. R. , Johnson H. R. , Thomas N. W. , Firth N. L. , Harrington R. B. , Judge M. D. 
Published: March 2009

SUMMARYSuppressed development of edible portion in carcasses from cattle fed hay during the early feeding period (216–340 kg live weight) was followed by compensatory growth during the intermediate (341–409 kg live weight) and final (410–454 kg live weight) periods. However, when silage in the early feeding period was followed by corn concentrate in the intermediate period, no increased ‘edible portion’ development was achieved beyond that produced by continuous silage. The final feeding period (corn concentrate) resulted in a decline in ‘edible portion’ percentage in cattle that previously received concentrate in the intermediate period whereas those that previously received silage remained at about the same percentage.Cattle fed hay during the early period had less (P > 0·01) carcass weight, less (P > 0·01) fat cover, and more (P > 0·01) reticulo-rumen weight than those fed corn silage for the same period, regardless of slaughter weight.In the heavy (409 and 454 kg) slaughter groups, cattle fed silage in the early period had higher (P > 0>05) marbling scores than those fed hay. Feeding silage in the intermediate period resulted in lower colour (P > 0·01) and firmness (P > 0·01) scores in the longissimus dorsi muscle than feeding concentrate at that time. The dietary regimes used in these studies resulted in widely varying growth rates among treatments with consequential differences in the average age of the animal groups at slaughter. Therefore, the treatment effects observed seem to be easily explicable on the basis of age differences.
The relationship between water and food intakes of european and zebu type steers
Authors: Phillips G. D. 
Published: March 2009

1. The ratios of water drunk:hay eaten were studied for groups of Zebu and grade Hereford steers.2. In all comparable conditions the ratio was significantly smaller for the Zebus.3. Restricting water availability to about half significantly reduced the ratios for both types of steers.4. The decrease in hay eaten resulting from restriction of water was less for the Zebus.5. Restricting the hay intake to approximately half significantly increased the ratios for both groups.6. The Zebus drank significantly less water than did the grades in relation to body weight.7. It is concluded that the results of water restriction may not be as disastrous as would have appeared likely from the constant ratio relationship of water and food intakes previously suggested, particularly in the case of the Zebu steers who have been shown to be better adapted to dry conditions.
The effect of fallow hoeing on cotton yields in rotations in the Sudan Gezira
Authors: Ferguson H. , Kordofani A. Y. , Roberts P. 
Published: March 2009

The average yields of irrigated long-staple cotton in the three-course rotations: dura, fallow, cotton, D-F-C; lubia, fallow, cotton, L-F-C; and fallow, fallow, cotton, F-F-C, were studied over 12 years in an experiment in the Sudan Gezira; the fallows (resting land) were either hoed or were left uncultivated during the rainy season, so that the effects of the operation of hoeing on the subsequent cotton yields could be measured.Where the fallows were unhoed L-F-C yielded more cotton than F-F-C, which gave at first higher yields than D-F-C, although this difference had disappeared by the end of the period. Fallow hoeing increased yields in all rotations; this response was maintained in D-F-C and L-F-C. In F-F-C the response to hoeing either fallow diminished steadily in time and whilst the higher response to hoeing both fallows also decreased, its rate of decrease was no greater than when only one fallow was hoed. The response to hoeing fluctuated considerably from year to year. In all rotations these fluctuations were associated with rainfall and the relationships have been expressed in the form of regression equations; separate equations were necessary for each rotation as the relationships were quite distinct.The variety X1730 A out-yielded Domains Sakel. There were interactions between the varieties and the other treatments, but these interactions were such that the varieties differed more at higher levels of yield and did not modify the above conclusions appreciably.
The effect of supplemental fat on the digestibility of the carbohydrates in compounded poultry diets
Authors: Bolton W. , Murty V. N. 
Published: March 2009

1. The digestibility of diets supplemented with fat has been investigated.2. For adult fowls and young chicks an increase in the fat content was accompanied by a decreased digestibility of the supplemental fat.3. Supplemental fat depressed the digestibility of the carbohydrates when added to a chicks' diet, but had no such effect on a layers' diet.
The potency of balancing interactions between dietary proteins. Chick experiments on the significance for prior judgement and use of herring proteins
Authors: Laksesvela B. 
Published: March 2009

1. The potency of balancing interactions between the protein of herring press-cake (dried) and solubles (condensed) on one side, and certain vegetable feeds on the other, has been examined on 2- to 4-week-old chicks:(a) Initially by comparing the co-effect of a series of different combinations of the herring products when ingested together with certain cereals plus extracted ground-nut meal, to that estimated earlier when the same combinations of herring products formed the sole dietary protein.(b) Thereafter by studying whether the co-effect of the herring products was influenced or not by substituting extracted soya-bean meal for the ground-nut meal.(c) Further by tentative trials to show that registered interactions were caused by some keystone amino acids.2. A special dietary system was devised for the purpose (a basal diet of actual feeds + a synthetic, practically protein-free basal diet + the tested feed, eventually + adjustments), the results being recorded as combinative protein value = c.p.v.3. Interactions between dietary constituents not only were shown under the circumstances, but proved to be an easily acting factor of great power. Herring solubles in proportions of 15–45% were formerly found to bring about a statistically significant improvement of the meal when fed together with this as the only protein of the diet. But: (a) the introduction of certain cereals and ground-nut readily converted the beneficial effect of the solubles into a significantly negative one. (b) Whereas soya-beans instead of ground-nut evidently reversed the situation again. In this third grouping solubles at moderate levels appeared neutral, meaning that herring solubles combined significantly better with soya-bean than with ground-nut when fed to young chicks in presence of a set of cereals and herring meal, (c) Responses to supplemental, crystalline amino acids showed that the interactions between the protein sources could be attributed to their constituent amino acids. Thus the little efficient combination of solubles and ground-nut plus certain cereals could be greatly improved by small quantities of all ten essential amino acids together, and equally much by lysine plus threonine only. Contrarily, the diet appeared weakened when lysine, threonine or isoloucine were omitted singly or together from the whole ten. The same was the case with single addition of leucine.4. The discussion stresses the pre-eminent importance of the diet in biological estimations of protein value. It also points out the practical significance of skilful combination of different protein sources.
Effects of egg-yolk-citrate and egg-yolk-glycine dilutors on the morphology of bovine spermatozoa
Authors: Mukherjee D. P. , Dott H. M. 
Published: March 2009

Twenty semen samples were collected by means of the artificial vagina from three Friesian and two Dexter bulls. In each sample, thehead lengthandhead breadthof spermatozoa which did not take up the nigrosin-eosin stain, and their percentage before and after 72 hr. of preservation in egg-yolk-citrate and egg-yolk-glycine, were studied. The following results were obtained from the study:1. No significant variation was found in the two measurements of sperm head before and after preservation in E.Y.C.2. Both thehead lengthandhead breadthof spermatozoa preserved in E.Y.G. were significantly less than those before and after preservation in E.Y.C..3. The change in size of the spermatozoa head in E.Y.G.. dilutor may be due to an alteration in the acrosome.
A comparison of the vegetative growth, development and seed yield of three varieties of cowpea, Vigna unguiculata (L.) Walp.
Authors: Ojehomon O. Ojeaga 
Published: March 2009

SUMMARYThe vegetative growth, flowering and seed yield of three cowpea varieties—Adzuki, Mala and New Era—with contrasting yields, were compared in one field and two greenhouse experiments. In the field the plants were spaced so far apart that they did not form a closed stand, but were effectively individuals, like the potted plants used in the greenhouse experiments. In all experiments New Era yielded most followed by Mala, although the differences between these two varieties were not significant, and Adzuki least.Seed yield and vegetative growth were not simply related. New Era with the highest seed yield had the largest vegetative dry weight, leaf area and leaf area duration (D), followed by Mala, with Adzuki always least in each parameter. However, the superiority of New Era in total dry weight and leaf area was much greater than in seed yield. Mala and Adzuki were more efficient than New Era in converting dry matter into seed. Large fractions of current assimilates moved from the leaves to the seed of Adzuki and Mala than of New Era.Varietal differences in relative growth rate, net assimilation rate, or leaf area ratio were too small to account for varietal differences in seed yield.New Era and Mala produced more flower buds than Adzuki. However, Adzuki developed the largest proportion of ripe fruits, but had more aborted seeds/fruit than New Era and Mala. Thus, increased flower production and fruit formation did not increase the production of mature seeds. Therefore, little would be gained by breeding or selecting for increased flower production. The heavier seeds of Mala and New Era compared with those of Adzuki contributed greatly to their larger yields. At the spacing of 3 ft x 1 ft used in the field, the leaf area index (L) and leaf area duration (D) were suboptimal, and closer spacing should increase yield.
Changes in egg shell thickness and white and yolk weight and composition over a period of a year
Authors: Jenkins N. K. , Tyler C. 
Published: March 2009

A study has been made of all eggs laid over a year (March-March) by twelve birds.It was found that:1. Shell thickness, yolk weight and white weight all increased with time.2. For each individual bird a linear relationship existed between yolk weight and yolk calcium weight and between yolk weight and yolk phosphorus weight.3. High calcium diets significantly increased shell thickness at the beginning of the experiment and yolk calcium around the middle of the experiment. Dietary calcium levels had no other effects and dietary phosphorus levels no effects at all.4. The ‘curves’ relating shell thickness and time for each individual bird are discussed in relation to the relative merits of different birds as producers of thick shells.
Fission products and the dairy cow IV. The metabolism of 131I following single and multiple doses
Authors: Garner R. J. , Jones H. G. 
Published: March 2009

1. The change in concentration of 131I with time in plasma, urine, milk and the thyroid gland has been followed in four cows after administration of either a single oral dose or of 131I from a decaying source every 6 hr. for 14 days.2. The observed changes in concentration following multiple doses have been compared with those predicted from the single-dose experiments.3. Small discrepancies were observed between the observed and predicted course of events in urine, milk and the thyroid gland: their significance is considered to be doubtful.
A study of various chemical treatments to remove lignin from coarse roughages and increase their digestibility
Authors: Chandra Suresh , Jackson M. G. 
Published: March 2009

SummarySeveral delignifying agents, used in various paper-making processes, have been compared for their ability to remove lignin and increase the digestibility of several roughages in laboratory experiments using a spray method of treatment recently suggested by Wilson & Pigden (1964). The chemicals were dissolved in small quantities of water which were then used to moisten the roughage. No washing was done after treatment. Sodium hydroxide was the most effective chemical; at a rate of 10 g per 100 g of roughage, the lignin content of ground maize cobs was reduced by 26% and rumen dry-matter digestibility increased by more than 100%. Bleaching powder was as effective as sodium hydroxide in removing lignin, but residual chlorine apparently inhibited rumen microbial digestion.Maize cobs, wheat and paddy straws, sorghum stover and sugar cane tops, though of widely differing initial digestibility, were brought to an equal level of rumen digestibility if treated with 4% or more of sodium hydroxide. Drying the treated roughage at 100 degrees instead of at room temperature increased digestibility only in the case of maize cobs. The alkali spray treatment was as effective in increasing the digestibility of chaffed as of ground wheat straw. Data are presented which show the amounts of residual alkali in treated roughage as a function of time after treatment and of concentration of alkali used in the treatment. Further, data are presented which show the loss of nutrients from treated roughage if washed as in the traditional method.
The digestion of bacterial mucopeptide constituents in the sheep: 1. The metabolism of 2, 6-diaminopimelic acid
Authors: Mason V. C. , White F. 
Published: March 2009

Summary1. In a series of experiments with cannulated lambs the amounts of 2, 6-diaminopimelic acid (DAPA) and a-amino nitrogen passing daily through the abomasum, terminal ileum and rectum were measured. While there was a very significant net absorption of α-amino nitrogen between the abomasum and terminal ileum, there was no net absorption of DAPA between these points. Indeed, there was a tendency for more DAPA to leave the terminal ileum than entered the abomasum, though this was only significant at the 10% level. In all cases significantly less DAPA passed out of the rectum than passed through the terminal ileum, indicating extensive degradation of this amino acid in the hind-gut, probably as a result of microbial activity.2. In adult sheep given control rations no DAPA could be detected in the blood, even when 643 ml plasma were analysed. These sheep usually excreted less than 5 mg DAPA daily in the urine.3. When synthetic DAPA was introduced into the peritoneum, blood, abomasum, rumen or caecum of cannulated adult sheep in physiological amounts, approximately 80, 83, 53, 5 and 0 % of the administered dose was recovered in the urine. Furthermore, when introduced into the abomasum, DAPA could be measured in plasma from the anterior mesenteric and jugular veins.4. It was concluded that in the normal sheep the DAPA-containing fraction of the bacterial cell-wall material synthesized in the rumen is not digested in the small intestine. In the caecum and colon, however, this fraction is extensively degraded by hindgut bacteria.