bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of beef breeds for rangeland weaner production in Zimbabwe 1. Productivity of purebred cows
Authors: Tawonezvi H. P. R. , Ward H. K. , Trail J. C. M. , Light D. 
Published: September 2010

ABSTRACTPurebred cows were evaluated for reproductive performance and live weight, and for pre-weaning growth and viability of crossbred progeny sired by unrelated breeds. The cows comprised three indigenous breeds, Mashona, Nkone and Tuli and four exotic breeds Africander, Brahman, Sussex and Charolais. Over 3 years, the mean calving rates % (s.e.) were 55·5 (3·0), 76·0 (3·8), 63·1 (4·5), 69·6 (3·5), 70·0 (3·8), 60·0 (4·3) and 67·0 (5·0) for Africander, Mashona, Nkone, Tuli, Brahman, Sussex and Charolais cows, respectively.Bos taurusand Brahman cows were heavier at parturition and at calf weaning than indigenous cows. Mashona cows were lightest at both stages. Calves ofBos tauruscows were heaviest at birth and those of Mashona lightest. Calves of Brahman cows had the most rapid growth rate and at weaning (240 days) weighed in kg (s.e.) 207 (3·1), compared with 184 (2·1), 172 (2·2), 187 (2·6), 184 (2·1), 178 (2·7) and 186 (2·9) for progeny of Africander, Mashona, Nkone, Tuli, Sussex and Charolais, respectively. Pre-weaning survival rates of the breeds were not significantly different but viability was higher in progeny of indigenous than exotic breeds. The productivity estimates combining calving rate, cow weight, calf weaning weight and pre-weaning viability demonstrated the superiority of indigenous breeds and the Brahman over Africander andBos taurusbreeds.
A two-pool model of tritiated water kinetics to predict body composition in unfasted lactating goats
Authors: Dunshea F. R. , Bell A. W. , Chandler K. D. , Trigg T. E. 
Published: September 2010

ABSTRACTA two-pool model of tritiated water kinetics was investigated as a means of partitioning total body water into empty body water and gut water in 17 lactating goats. Empty body water, gut water and total body water were of a similar magnitude to, and highly correlated with, a rapidly equilibrating tritiated water pool, a more slowly equilibrating pool and the sum of these two pools, respectively.Empty body fat was poorly correlated with both live weight and empty body weight (R2 = 0·42 and 0·51, respectively). However, there was a strong inverse relationship between the water and fat contents of the empty body. Consequently, empty body fat was accurately predicted by a multiple regression equation which included both empty body weight and empty body water as independent variables (R2 = 0·97). Substitution of these variables with estimates derived from tritiated water kinetics still resulted in a high correlation (R2 = 0·88). Tritiated water kinetics offered little improvement over live weight alone in the prediction of empty body protein, empty body ash or fat-free empty body.
The value of cloning in MOET nucleus breeding schemes for dairy cattle
Authors: Woolliams J. A. 
Published: September 2010

ABSTRACTThe value of cloning in MOET nucleus breeding schemes has to be considered within the constraint of fixed resources. Under this constraint cloning was found to add to genetic progress only when (i) the heritability is low and (ii) it is used at the expense of a reduction in the number of bull families. This course would exacerbate inbreeding and other potential problems with MOET. All other options for using clones lead to a reduction in genetic progress due to a loss of selection intensity that is not made up for by gains in selection accuracy.
Water-washed neem (azadirachta indica) seed kernel cake in the feeding of milch cows
Authors: Nath K. , Agrawal D. K. , Hasan Q. Z. , Daniel S. J. , Sastry V. R. B. 
Published: September 2010

ABSTRACTA full lactation (300 days) experiment on 32 crossbred milch cows, separated into two groups was carried out. Group 1 (control) was given a concentrate mixture consisting of 400 g groundnut cake, 300 g crushed maize, 270 g wheat bran, 20 g mineral mixture and 10 g common salt per kg; while in group 2 (experimental) the groundnut cake was replaced by water-washed neem seed kernel cake (WWNSKC). Roughage was common in both the groups. Digestion and balance study on nine cows in group 1 and eight in group 2 was carried out after 3 months experimental feeding. Milk yield was recorded twice daily and butter fat, protein and total solids were determined every month in the milk of each animal. The results showed that there was no significant difference (P > 0·05) in the milk yield, butter fat content, organoleptic evaluation of milk, dry-matter intake, digestibility of nutrients, haemoglobin, SGOT, SGPT, acid phosphatase and alkaline phosphatase in blood and reproductive ability of the cows in the two groups. The nitrogen balance was higher in the WWNSKC group (P < 0·05) due mainly to less excretion of urinary nitrogen and a concomitent decrease in blood urea nitrogen. It is concluded that water washing of neem seed kernel cake, whose potential availability in India alone is about 0·9 Mt annually, can convert this cake, hitherto going waste, into an excellent high protein animal food and can be used for feeding milch animals without any adverse effect. It is recommended that this technology be adopted by all neem seed-cake producing countries, specially those developing countries having chronic shortage of foods and fodders for animal feeding.
Cottonseed for protein and energy supplementation of high-roughage diets for beef cattle
Authors: Brosh A. , Holzer Z. , Levy D. 
Published: September 2010

ABSTRACTThe use of cottonseed (CS) as an energy and protein supplement to high wheat-straw diets was studied in a digestion and nitrogen balance trial, and as a component in fattening diets in a feeding trial. The proportions of CS studied were 0, 60, 120, 180 and 240 g/kg diet dry matter (DM). DM intake per kg M0·75 was 33, 31, 40, 31 and 29 g, respectively. The digestibility coefficient of organic matter was 415, 463, 417, 441, 350 g/kg DM and of neutral-detergent fibre was 350, 436, 411, 309, 334 g/kg DM. Nitrogen balance was –2·52, 1·1, 5·38, 5·63, 7·60 g/day respectively, for the same order of treatments. The effect of high proportions of CS in the diet in restricting DM intake and reducing its digestibility was evident. The results of the feeding trial were in agreement with those of the digestion trial and indicate the proportion of 120 g CS per kg DM as optimal and maximal.
Rumen degradation of straw. 8. Effect of alkaline hydrogen peroxide on degradation of straw using either sodium hydroxide or gaseous ammonia as source of alkali
Authors: Adebowale E. A. , Ørskov E. R. , Hotten P. M. 
Published: September 2010

ABSTRACTThe comparative effect of spraying wheat straw, maize stover and maize cob with sodium hydroxide and alkaline (sodium hydroxide treated) hydrogen peroxide over a range of moisture contents was evaluated. The effect of concentration of hydrogen peroxide on straw subsequently ammoniated was also investigated. No differences (P < 0·05) were detected between sodium hydroxide and similar concentrations of sodium hydroxide used to provide alkali for alkaline hydrogen peroxide treatments. When however, gaseous ammonia was used as the source of alkali there were significant linear increases in degradability with increasing concentrations of hydrogen peroxide. At 48 h incubation, degradability values for untreated, ammonia-treated, 10, 50 and 100 g alkaline (ammonia) hydrogen peroxide per kg were 528, 595, 640, 676 and 716 for wheat straw, 618, 652, 683, 717 and 743 for maize stover and 392, 467, 585, 632 and 686 g/kg for maize cob respectively. It is concluded that the use of gaseous ammonia as the source of alkali seems a possible practical method of using hydrogen peroxide to increase degradability of straws.
Environmental modifications in a pig growth model for early-weaned piglets
Authors: Jacobson L. D. , Cornelius S. G. , Jordan K. A. 
Published: September 2010

ABSTRACTA food-driven pig growth model was developed from two existing mathematical models. The new model predicts daily growth and heat production of early-weaned pigs. An existing pig growth model was altered by replacing the environmental component with a heat transfer model. The heat transfer model was further refined by partitioning latent heat loss between the skin and lungs, adding a thermal resistance for hair coat, and increasing tissue thermal resistance. Results from this combined model were compared with experimental observations of daily piglet growth and heat production at 15°C, 20°C, 25°C and 30°C. Good agreement existed between observed data and model predictions for piglet growth. Heat production predictions did not compare as well with experimental observations as did growth, especially when piglets lost weight.
Pituitary responses of seasonally anoestrous ewes to long-term continuous infusion of low doses of GnRH
Authors: Khalid M. , Haresign W. , Hunter M. G. , McLeod B. J. 
Published: September 2010

ABSTRACTThe response to long-term continuous infusion of gonadotrophin releasing hormone(GnRH)was monitored in progesterone-treated seasonally anoestrous ewes. Using osmotic pumps, groups of five ewes eachreceived 0(controls),125, 250, 500 or 1000 ng GnRH per h subcutaneously for a period of 21 days. Bloodsamples were collecte dat 30-minintervals from 6 h before until 24 h after the start of treatment and then for 8-h periods on days 2, 8, 15 and 21. After 21 days of treatment all the ewes were slaughtered to determine pituitary GnRH receptor numbers. Continuous infusion of GnRH resulted in a short-lived (2day)increase in plasma LH and oestradiol concentrations after which they were not different from the pre-treatment values. Over the later period of treatment when the pituitary gland was not responding to the exogenous GnRH(days 8, 15 and 21), LH episodes(presumably due to endogenous GnRH secretion fromthe hypothalamus) were observed. Continuous infusion of GnRH was also associated with a suppression in plasma FSH concentrations, the duration of which was dose-dependent. Only at the highest GnRH dose level(1000 ng/h)was there a significant reductionin pituitary GnRH receptor content.
Effects of cimaterol on energy utilization for maintenance and for protein and fat deposition by wether and ewe lambs given chopped lucerne hay or lucerne-barley pellets
Authors: Sainz R. D. , Wolff J. E. , Upsdell M. P. 
Published: September 2010

ABSTRACTThe effects of sex (wethersv.ewes), diet (chopped lucerne hayv.lucerne-barley pellets) and cimaterol on energy utilization by Suffolk cross lambs were determined by comparative slaughter. Quadratic regression of energy retention (RE) on metabolizable energy intake (MEI) enabled estimation of maintenance energy requirements (Em), efficiencies of gain (ktotal) and maximum rates of gain (REMAX). Regressions using RE in fat and proteinv.MEI yielded analogous parameters for fat and protein deposition (Em fat, kfat, REMAX fatand Emprotcin, kprolein, REMAXprotcinrespectively). Emwas lower in wethers than ewes (455v.510 kJ/kg M0·75per day respectively), but was unaffected by diet or cimaterol. Sex and cimaterol did not affect ktotai. which was higher in lambs given pellets compared with lambs given hay (0·417v.0·224 respectively). Similarly, REMAXwas higher in lambs given pellets than in lambs given hay (326v.114 kJ/kg 0·75 per day respectively). None of the groups differed significantly in the parameters of fat deposition, which averaged 480 kJ/kg 0·75 per day for Emfal, 0·224 for ktat, and 250 kJ/kg M0·75per day for REMAX, fat-Em.proteinwas lower in wethers than in ewes (466v.569 kJ/kg 0·075 per day, respectively), and was further reduced by cimaterol (418 and 507 kJ/kg 0·75 per day for wethers and ewes respectively). Estimates of kprotcin were higher in wethers than in ewes (0·091v.0·064 respectively), and were increased by cimaterol (0·115 and 0·089 for wethers and ewes respectively). Similarly REMAX protein was higher in wethers than in ewes (47v.37 kJ/kg 0·75 per day respectively), and was increased by cimaterol (58 and 48 kJ/kg 0·75 per day for wethers and ewes respectively). The repartitioning action of cimaterol was additive with effects of diet, intake and sex.
Comparison of Duroc and British Landrace pigs and the estimation of genetic and phenotypic parameters for growth and carcass traits
Authors: Cameron N. D. 
Published: September 2010

ABSTRACTDuroc and halothane negative British Landrace boars and gilts were performance tested on ad libitum or restricted feeding regimes, with like-sexed non-littermate groups of one, two, three or four pigs per pen. There was a total of 320 pigs with 20 litter groups per breed with four boars and four gilts per litter group. Within each feeding regime, a boar and a gilt from each litter were tested on one of two diets in 1986, for each of the four combinations, and pigs were tested similarly for two other diets in 1987. Carcass composition was determined by half-carcass dissection of 160 pigs allocated between treatments.There was a breed × sex interaction for growth and performance traits for pigs fed ad libitum. Duroc boars were faster growing and more efficient than Landrace boars, but Duroc gilts grew more slowly and were less efficient than Landrace gilts. On restricted feeding, Duroc pigs were more efficient than Landrace pigs.At constant slaughter weight, Duroc pigs had less subcutaneous fat but more intermuscular fat. Although they had less separable fat in the carcass, Duroc pigs were not leaner as weights of bone, skin, head, feet and tail were heavier than for Landrace pigs.Group penning and group feeding of pigs may have enhanced competition effects resulting in positive genetic and phenotypic correlations between growth rate and backfat depths on both feeding regimes.The positive genetic correlation between growth rate and fat deposition resulted in a negative genetic correlation between growth rate and carcass lean content and a lower genetic correlation with lean tissue growth rate than in other studies.
Efficiency of nucleus breeding schemes in dual-purpose cattle of Tanzania
Authors: Kasonta J. S. , Nitter G. 
Published: September 2010

ABSTRACTFor the Mpwapwa cattle breed in Tanzania, the efficiency of various breeding schemes including an open nucleus was investigated by model calculations. Artificial insemination and intensive recording of production are assumed to be applied in a nucleus which is the main breeding unit. As a pre-nucleus, associated herds with less intense data recording serve as the basis to screen superior cows for nucleus replacements, provide the capacity for progeny testing, and operate as bull multipliers for commercial herds.The criteria of efficiency were genetic gain and profit from selection for a dual purpose breeding objective (milk and beef) in a total population of 10 000 cows. Introducing a two breeding tier scheme through separating all recorded cows into a nucleus and pre-nucleus leads to an increase of the genetic gain rather than the profit. Further improvement is obtained by introduction of artificial insemination in pre-nucleus herds. The nucleus size should not exceed about 5% of the cow population and an optimum size of the pre-nucleus is about 15%. Opening the nucleus to replacement cows coming from the pre-nucleus affects the aggregate genetic gain very little although it can be recommended if milk yield is to be mainly improved or if the total profit is taken into account. Furthermore, the nucleus should be opened if there is little difference between the heritabilities in the nucleus and pre-nucleus and also in order to avoid detrimental effects of inbreeding and genotype × environment interaction.
The dietary requirements of calcium and phosphorus for growing lambs
Authors: Wan Zahari M. , Thompson J. K. , Scott D. , Buchan W. 
Published: September 2010

ABSTRACTGroups of wether lambs were fed on four concentrate diets, from a live weight (LW) of about 25 kg until they had grown to about 50 kg, when they were killed, minced and analysed. A fifth group was killed at the start of the trial to provide data on their initial composition. The dietary treatments were identical except in their concentrations of calcium (Ca) and phosphorus (P) and supplied, with some approximations: (A) 0·75 times the requirements for Ca and P estimated according to the recommendations of the AFRC Technical Committee on Responses to Nutrients (TCORN, 1990); (B) a close match to the estimated requirements for both elements; (C) 1·5 times the estimated requirements for both elements; (D) 1·5 times the Ca requirement and 0·75 times the P requirement.The retentions of Ca and P in the lambs were closely similar with diets B and C (6·8 and 7·3 g Ca per kg LW and 4·1 and 4·5 g P per kg LW) and significantly lower with diet A (4·8 g Ca and 3·0 g P per kg LW) and diet D (5·0 g Ca and 2·7 g P per kg LW). Parallel differences in response to diet were evident in the composition of the metacarpi. Plasma Ca and P concentrations showed no significant differences between the dietary treatments A, B and C, but plasma P concentrations were markedly depressed with lambs on diet D and plasma Ca concentrations were elevated in this group. Rumen P concentrations were also markedly lower in lambs on diet D and their food intakes and growth rates were lower than in lambs in other groups. The results indicate that Ca and P retentions were not increased by feeding these elements in excess of their estimated requirements and were reduced when Ca and P or P alone was reduced proportionately to about 0·75 times requirement. The data are in accord with the TCORN recommendations and suggests that they provide a satisfactory basis for defining Ca and P requirements for growing lambs.
Experimental design for comparative digestibility trials with pigs: limitations of Latin squares
Authors: Goedhart P. W. 
Published: September 2010

ABSTRACTIn comparative digestibility trials with growing pigs Latin squares are widely used as experimental designs. In this paper conditions for the application of Latin squares are explicitly stated and checked with real data. Data were collected at the Institute for Livestock Feeding and Nutrition Research in the Netherlands and consisted of digestibility trials run on pigs of 40 to 100 kg live weight. There is strong evidence for a certain form of period × animal interaction in the data. This may seriously affect estimates of treatment effects and results of significance tests. It is concluded that Latin squares are unsuitable for comparative digestibility trials with pigs growing from 40 to 100 kg. When there is no interest in statistical comparison of the diets under study, Latin squares can still be used. Some suggestions for alternative designs are given.
An evaluation of an inoculant of Lactobacillus plantarum as an additive for grass silage for dairy cattle
Authors: Mayne C. S. 
Published: September 2010

ABSTRACTHerbage from the first regrowth of perennial ryegrass based swards was direct-ensiled following treatment with either an inoculant of Lactobacillus plantarum (Ecosyl, Imperial Chemical Industries pic) at 3·0 1/t, formic acid (850 g/kg) at 2·9 1/t, or no additive (control). During harvesting, alternate loads of inoculant material were treated with an absorbent polymer (ammonium polyacrylamide) at the rate of 1 kg/t herbage and ensiled in separate 100-t capacity silos. The mean dry matter (DM) and water soluble carbohydrate concentrations of herbage used for the four treatments was 157 and 120 g/kg respectively. Lactic acid levels post ensiling increased more rapidly in inoculant-treated herbage than with the other treatments. Formic acid and inoculant-treated silages were well preserved whereas control and inoculant-plus-polymer silages were only moderately well preserved. Losses of DM during ensilage were greater with the formic acid treatment with DM recovery values of 0·78, 0·72, 0·76 and 0·73 for the control, formic acid, inoculant and inoculant-plus-polymer silages respectively. Treatment of herbage with an absorbent polymer prior to ensiling resulted in a proportional reduction in effluent volume of 0·2 whereas formic acid treatment increased effluent flow by 0·28. The silages were evaluated in a changeover design experiment with two periods each of 4 weeks duration, using 24 British Friesian dairy cows. Animals were housed in individual stalls and in addition to the treatment silages, received 5 kg/day of supplement containing 193 g crude protein per kg DM. Silage intakes were increased by proportionately 0·10, 0·14 and 0·05 respectively with the formic acid, inoculant and inoculant-plus-polymer treatments compared with the control. The increased silage intakes with the inoculant treatment were reflected in an increased milk yield of 1·1 kg milk per day whereas formic acid and inoculant-plus-polymer treatments had no significant effect, although formic acid treatment did result in a significant increase in milk fat concentration. There were no major differences between treatments in energy or nitrogen digestibility, when determined on a complete ration basis. In conclusion, a large milk yield response was obtained as a result of treatment of herbage with inoculant prior to ensiling and this resulted from increased silage and hence energy intake. Treatment with formic acid increased silage and energy intake but had no effect on milk energy output.
Selection for rate and efficiency of lean gain in Hereford cattle 1. Selection pressure applied and direct responses
Authors: Mrode R. A. , Smith C. , Thompson R. 
Published: September 2010

ABSTRACTSelection of bulls for rate and efficiency of lean gain was studied in a herd of Hereford cattle. There were two selection lines, one selected for lean growth rate (LGR) from birth to 400 days and the other for lean food conversion ratio (LFCR) from 200 to 400 days of age, for a period of 8 years. A control line bred by frozen semen from foundation bulls was also maintained. Generation interval was about 2·4 years and average male selection differentials, per generation were 1·2 and — 1·1 phenotypic standard deviation units for LGR and LFCR respectively.Genetic parameters and responses to selection were estimated from the deviation of the selected lines from a control line and by restricted maximum likelihood (REML) techniques on the same material. Realized heritabilities were 0·40 (s.e. 0·12) for LGR and 0·40 (s.e. 0·13) for LFCR using the control line. Corresponding estimates from REML were 0·42 (s.e. 0·10) and 0·37 (s.e. 0·14). The estimate of the genetic correlation between LGR and LFCR was about — 0·69 (s.e. 0·12) using REML.The estimates of direct annual genetic change using deviations from the control were 3·6 (s.e. 1·3) g/day for LGR and — 0·14 (s.e. 0·07) kg food per kg lean gain for LFCR. Corrsponding estimates from REML were similar but more precisely estimated. The correlated responses for LFCR in the LGR line was higher than the direct response for LFCR.