bluuebunny/crossref_metadata_2025_split huggingface dataset:
The response of growing pigs to amino acids as influenced by environmental temperature. 1. Threonine
Authors: Ferguson N.S. , Arnold G.A. , Lavers G. , Gous R.M. 
Published: August 2016

AbstractTwo similar experiments (1 and 2) were conducted to measure the effects of a range of dietary threonine concentrations and environmental temperatures on the performance of pigs grown from 13 to 25 kg live weight. In both experiments 48 Large White x Landrace entire male pigs were assigned at 13 kg to one of six dietary threonine treatments (8·9 (T1), 7·6 (T2), 6·2 (T3), 4·9 (T4), 3·6 (T5) g/kg and T5 + supplemented threonine (T6)) and one of four temperature treatments (18, 22, 26 and 30°C). Animals were given ad libitum access to food until 25 kg live weight. There were significant interactions (P < 0·05) between temperature and threonine content on the rate of growth (ADG) with the highest gains on T1 and at 22°C. Similarly the response in food intake (FI) to dietary threonine was significantly (P < 0·01) modified by the ambient temperature. An increase in the supply of threonine in the diet resulted in significant increases (P < 0·001) in the gain per unit of food (FCE). A similar response to temperature occurred with the highest FCE recorded at 26°C and the lowest at 18°C. There was a 0·20 proportional reduction in body protein content at 25 kg live weight in pigs given T5 compared with those given T1 and similarly, excluding T6 because threonine may not have been the most limiting amino acid, the fat content was 1·37 higher for pigs on T5 versus T1, which had the lowest fat content. Similar trends occurred in protein and lipid growth rates with maximum protein deposition recorded on T1 (86 (s.e. 3·5) g/day) and maximum lipid deposition on T5 (108 (s.e. 5·8) g/day), over all temperatures. The response in total heat loss was similar to that observed in FI with the effect of decreasing threonine content being dependent on the environmental temperature. Linear regression of daily empty body threonine accretion on daily digestible threonine intake showed an average efficiency of threonine utilization for pigs between 12 kg and 25 kg live weight of 0·59 (s.e. 0·03). There were no differences in efficiency between temperatures. In conclusion, decreasing the threonine concentration below the requirement of the animal ‘resulted in a significant decrease in ADG, reduced FCE and fatter animals. Pigs given a diet deficient in threonine will attempt to maintain threonine intake as the concentration declines by increasing food intake but this compensation is dependent on the environmental temperature. Pigs are able to compensate better for a deficiency in threonine at 18°C and 22°C than at higher temperatures due to the animals being able to dissipate more heat at the lower temperatures.
The changes in body weight and plasma metabolite levels during leptin injection are caused by the reduction of food intake in sheep
Authors: Tokuda T. , Matsui T. , Ito J. , Torii S , Yano H. 
Published: August 2016

AbstractLeptin is thought to act on the central nervous system as an important regulator of food intake and body weight in mice. To examine the actions of leptin in sheep, we injected recombinant mouse leptin into the lateral cerebral ventricle of ewes. Six ewes were intracerebroventricularly cannulated and given free access to forage and water. The ewes were injected with phosphate-buffered saline (PBS) as a vehicle for 5 days through the cannula and then with PBS + leptin for 7 days consecutively. Although food intake and body weight did not change during PBS injection, the administration of leptin decreased food intake and body weight. Plasma glucose levels decreased and plasma non-esterified fatty acid levels increased on the last few days of leptin administration. Approximately 2 weeks after normal food intake was recovered, the amount of diet was individually reduced in accordance with the recorded food intake during the leptin administration in each sheep. During food restriction, body weight and plasma metabolite concentrations were similarly changed as during the leptin-administration period. These results indicate that leptin decreases food intake in sheep. Moreover, it is likely that the changes in body weight and plasma metabolites were mainly induced by the suppression of food intake during leptin injection.
Birth weight responses to shearing ewes in early to mid gestation
Authors: Morris S.T. , McCutcheon S.N. , Revell D.K. 
Published: August 2016

AbstractThis study compared the effect on foetal growth of shearing ewes in very early pregnancy (day 50) with the effect of shearing later in pregnancy (day 70 or 100). One hundred and sixty ewes were allocated at day 49 of pregnancy to four ‘time of shearing’ treatments — pregnancy day 50 (P50), P70, P100 (no. = 45 ewes per treatment) and unshorn (shearing of this group occurred 43 days after weaning) (no. = 25); two methods of shearing (by standard comb and cover comb); and two levels (1 or 2) of pregnancy/rearing rank. All ewes had been mated over a 28-day period and grazed pasture throughout the trial. The mid point of lambing was 27 August 1996. Live weights of ewes (corrected for fleece weight) were not influenced by shearing time at any stage except at day 45 of lactation when ewes shorn at P50, P70 or P100 were about 3⋅0 kg lighter than unshorn ewes. Shearing method had no effect on ewe live weight. Time of shearing and shearing method had no effect on ewe greasy fleece production or wool tensile strength. Shearing significantly (P < 0⋅05) influenced the birth weight of single- (by 0⋅7 to 0⋅8 kg) but not twin-born lambs. Maternal plasma triiodothyronine concentration increased proportionately by 0⋅47 to 0⋅85 (P < 0⋅05) and lasted for at least 20 days in response to shearing irrespective of time of shearing. No difference in plasma insulin concentration was detected between shearing groups but plasma glucose concentration proportionately increased by 0⋅06 to 0⋅16 (P < 0⋅05) for 10 to 20 days after shearing. These results indicate that shearing between day 50 and 100 of pregnancy can increase lamb birth weights and that the response is associated with an increase in thyroid hormone concentrations in the maternal circulation.
Differences in food resource allocation in a long-term selection experiment for litter size in mice 1. Developmental trends in body weight and food intake against time
Authors: Rauw W. M. , Luiting P. , Verstegen M. W. A. , Vangen O. , Knap P. W. 
Published: August 2016

AbstractDifferences in the metabolic resource situation between non-reproductive male and female mice of a line selected for high litter size at birth (average of 22 born per litter) and a non-selected control line (average of 10 born per litter) were investigated in two replicates. Brody curves were fitted to individual data on body weight against age and linear regression lines were fitted to individual data on cumulative food intake against age. Mature body weight and mature daily food intake were higher in selected mice than in control mice and higher in males than in females. Selected males matured faster than selected females and control mice. In general, differences in growth and food intake curves between species or lines can mostly be explained by differences in mature size. Therefore, parameters were subsequently scaled by individual estimates of mature body weight. Differences that remain after scaling are a consequence of what have been called specific genetic factors. Scaled mature food intake was higher in selected mice than in control mice and higher in females than in males. Scaled maturation rate was higher in selected mice than in control mice and higher in selected males than in selected females. This shows that in the present study, specific genetic factors have been detected for both body weight and food intake, which suggests that selection for increased litter size has disproportionally changed the resource allocation pattern.
Menadione nicotinamide bisulphite as a source of vitamin K and niacin activities for the growing pig
Authors: Marchetti M. , Tassinari M. , Marchetti S. 
Published: August 2016

AbstractWhen compared with other menadione derivatives such as menadione sodium bisulphite (MSB), menadione nicotinamide bisulphite (MNB), an organic salt combining menadione and nicotinamide, shows better stability towards physical and chemical factors once it is added to pre-mixes or foods. The present work evaluates the bioavailability of the two vitamins present in this compound and toxicity in the pig. To assess vitamin bioavailability, pigs were given small amounts of food containing MNB or equivalent amounts of MSB and nicotinamide in the free form. Menadione and nicotinamide concentrations in blood samples drawn at set times after the diets were given did not reveal any significant differences between the two modes of administration. Haematic levels of both vitamins in animals receiving MNB, or MSB and nicotinamide, were after 2, 4, 8 and 12 h higher (P< 0·001) than those of untreated animals. The tolerance level to MNB was evaluated in pigs given diets containing graded amounts of MNB (100, 500, 2500 mg/kg) for 28 days. No significant (P> 0·05) differences were recorded in live weight, food intake and gain/food ratio in pigs given these diets when compared with those given an unsupplemented diet. Haemoglobin and bilirubin levels did not differ between animals given various amounts of MNB and control animals. Plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities in pigs given 100 mg/kg of MNB did not show significant differences when compared with those observed in pigs given an unsupplemented control diet. In pigs on the diets supplemented with 500 and 2500 mg/kg of MNB there was a significant increase in the two enzymatic activities as compared with controls (P< 0·001 andP< 0·01). In the case of ALT this had disappeared by 28 weeks. MNB is a good source of vitamin K for the pig and does not appear to have any adverse effects, even when administered at levels higher than those normally used in pig food supplementation.
Prediction of lean meat proportion based on ultrasonic backfat thickness measurements of live pigs
Authors: Hulsegge B. , Merkus G. S. M. , Walstra P. 
Published: August 2016

AbstractIn The Netherlands a system has been developed for classification of live pigs based on lean meat proportion. Ultrasonic backfat thickness measurements were taken on 377 live pigs to assess the ability of the developed system for estimation of the lean meat proportion. The measurements were made at the sites mid point (half the distance from the occipital bone to the base of the tail), mid point –2·5 cm and mid point +2·5 cm, 5 cm off the dorsal mid line.On the same day, these pigs were slaughtered and the lean meat proportions of the carcasses were estimated using the Hennessy Grading Probe (HGP). HGP measurements were taken between the third and fourth from last rib, 6 cm off the dorsal mid line on carcasses (3/4 LR). The day after slaughter, 88 left carcass sides were randomly chosen to be dissected according to a simplified European Union (EU) reference method.From the fat thicknesses measured, the one at the site mid point on live pigs was the most accurate predictor for the EU lean meat proportion. The use of multiple site measurements, compared with a single site measurement, significantly reduced the residual standard deviation for the estimation of lean meat proportion.The site mid point on live pigs differed in longitudinal as well as in dorsal-ventral direction from 3/4 LR on carcasses.The results of this study suggest that multiple backfat thickness measurements on live pigs can be used for prediction of lean meat proportion with sufficient precision for practical use. Therefore, the developed system can serve as a classification system for live pigs.
Effect of nutrient density and group size on the performance of growing and finishing pigs given food using single-space feeders
Authors: O’Doherty J. V. , McKeon M. P. 
Published: August 2016

AbstractA 2 ✕ 2 ✕ 3 factorial arrangement of treatments used 522 boars to examine the main effects and interactions of season (spring v. summer), number of pigs per pen with a single-space feeder (13 or 16 pigs per pen with a singlespace feeder; 0·78 m2 per pig v. 0·65 m2 floor space per pig) and nutrient density of the diet (12·5 g lysine per kg and 14·0 MJ digestible energy (DE) per kg from 38 kg to slaughter (high), 12·5 g lysine per kg and 14·0 MJ DE per kg during the growing phase and 10·0 g lysine per kg and 13·6 MJ DE per kg during the finishing phase (split) and 10 g lysine per kg and 13·6 MJ DE per kg from 38 kg to slaughter (low)) on the performance and carcass characteristics of growing and finishing pigs. The smaller group of pigs had a higher food intake during the grower-finisher period than the high stocked pigs (P < 0·01). The pigs had a higher lysine intake in the spring than in the summer months (P < 0·05). Differences in daily food intake for the smaller group of pigs were reflected in increased growth rate during the grower-finisher period (P < 0·001). However these pigs had a poorer food conversion ratio during the grower-finisher period (P < 0·05) than the bigger group of pigs. The pigs offered the high specification and split-fed diets had better growth rate (P < 0·05) than the pigs given the low specification diet during the grower and finisher period. There was a significant two-way interaction in growth rate between dietary treatment and season during the finisher period (P < 0·01). The pigs given the high specification diet had a better growth rate (P < 0·001) than the pigs given the low diets during the summer months. However, the high specification diet depressed growth rate during the spring months (P < 0·05). The pigs had a lower backfat and higher lean meat in the summer than in the spring months (P < 0·05).
Intake and growth of steers offered different allowances of autumn grass and concentrates
Authors: French P. , O’Riordan E. G. , O’Kiely P. , Caffrey P. J. , Moloney A. P. 
Published: August 2016

AbstractThe aim of this experiment was to quantify the relationship between autumn grass supply and concentrate supplementation level on grass intake and animal performance. One hundred and ten continental steers (567 kg) were assigned to 10 treatments. The experimental design was a three grass allowances (6, 12 and 18 kg dry matter (DM) per head daily) by three concentrate levels: (0, 2·5 and 5 kg per head daily) factorial with a positive control group offered concentrates ad libitum and no grass. Grass allowance was offered daily and concentrates were given individually. The experiment began on 22 August and all animals were slaughtered after a mean experimental period of 95 days. Grass intake was calculated using the n-alkane technique and diet digestibility using ytterbium acetate as an indigestible marker. There was an interaction (P < 0·05) between grass allowance and concentrate level for grass intake. At the low grass allowance there was no effect of offering animals supplementary concentrates on grass intake, at the medium and high grass allowances, supplementary concentrates reduced grass intake by 0·43 and 0·81 kg DM respectively per kg DM concentrate offered. Increasing grass allowance increased (P < 0·001) complete diet organic matter (OM) digestibility at all concentrate levels and supplementary concentrates increased (P < 0·001) complete diet OM digestibility only at the low grass allowance. Both offering animals supplementary concentrates (P < 0·001) and increasing daily grass allowance (P < 0·001) increased their carcass growth rate. Relative to the animals offered the low grass allowance and no concentrate, supplementing with concentrate increased carcass growth by 116 g/kg concentrate DM eaten whereas increasing the grass allowance, increased carcass growth by 38 g/kg DM grass eaten. As a strategy for increasing the performance of cattle grazing autumn grass, offering supplementary concentrates offers more scope than altering grass allowance.
Genetic and economic relationships between somatic cell count and clinical mastitis and their use in selection for mastitis resistance in dairy cattle
Authors: Kadarmideen H. N. , Pryce J. E. 
Published: August 2016

AbstractClinical mastitis (CM) and monthly test-day somatic cell count (SCC) records on Holstein cows were used to investigate the genetic and economic relationship of lactation average (of natural logarithms of) monthly test-day SCC (LSCC) with CM. After editing, there were 23663 lactation records on 17937 cows from 257 herds. Three groups of herds were first identified as having low (L), medium (M) and high (H) incidences of CM from the original or pooled (P) data set. Genetic parameters were estimated for the original and three data sub-sets (derived from the three herd groups). Expected genetic responses to selection against CM were calculated using genetic parameters of each data set separately, with an adapted version of the UK national index (£PLI-profitable lifetime index). Indirect economic values of SCC (EVSCC) were calculated as the direct cost of CM per cow per lactation weighted by the genetic regression coefficient of CM lactation records on their sires’ predicted transmitting ability for SCC (PTASCC). All genetic regression analyses were based on linear and threshold-liability models. Heritabilities and repeatabilities, respectively, were 0034 and 0·111 for CM and 0120 and 0·347 for LSCC in the original data set. Genetic, permanent environmental, residual and phenotypic correlations between CM and LSCC for the original (pooled) data set were 0·70, 0·44, 013 and 0·20, respectively. Parameter estimates for the three herd groups differed, with magnitude of the estimates increasing with increase in incidence from L to H herd groups. The EVSCCper unit of PTASCCfor L, M, H and P herd groups, respectively, were £004, £0·15, £0·33 and £018 on the observed and £0·86, £0·96, £1·22 and £110 on the underlying-liability scales. Selection for mastitis resistance, using SCC as an indicator trait in an extended version of £PLI, resulted in a selection response of 0·9, 21, 1·7 and 1·9 more cases per 100 cows after 10 years of selection in L, M, H and P herd groups, respectively. These results suggest that genetic responses to selection for CM resistance as well as the EVSCCare specific to herd incidence and hence would be appropriate for customized selection indexes. The increase in CM cases was greater when CM was excluded from the £PLI (2·8v1·9), hence it is recommended that CM should be included in the breeding goal in order to arrest further decline or to make improvement in genetic resistance to clinical mastitis.
Genetic resistance to gastro-intestinal nematode parasites in Galla and Small East African goats in the sub-humid tropics
Authors: Baker R. L. , Audho J. O. , Aduda E. O. , Thorpe W. 
Published: August 2016

AbstractA study was carried out from 1992 to 1996 to compare the resistance to naturally acquired gastro-intestinal (GI) nematode parasite infections (predominantly Haemonchus contortus) of Galla and Small East African goats in the sub-humid coastal region of Kenya. A total of 204 Galla and 349 Small East African (SEA) kids were born from five kiddings. These were the progeny of 18 Galla and 17 SEA bucks. Live weights (LWT), blood packed-cell volume (PCV) and faecal egg count (FEC) were recorded at 1- to 2-month intervals from birth to about 14 months of age. The SEA kids were more resistant to GI nematode parasites than Galla kids as shown by their significantly lower FEC (P< 0·001) in the post-weaning period (8- to 14-month-old kids) and lower mortality from birth to 14 months of age (P< 0·05). There was no significant (P> 0·05) breed effect on PCV, but Galla kids were significantly heavier (P< 0·001) at all measurement times between birth and 14 months of age. Heritability estimates for LWT, PCV and FEC at the different sampling times were characterized by high standard errors. Heritability estimates for records taken at 4·5 and 8 months of age from a repeated measures analysis were 0·18 (s.e.0·08) for PCV and 0·13 (s.e.0·07) for logarithm-transformed FEC. The phenotypic and genetic correlation estimates between PCV and LFEC were moderately to highly negative and averaged –0·36 and –0·53, respectively. The results are discussed in relation to the limited evidence for resistance to GI nematode infections in goats and compared with the much stronger evidence for resistance in sheep.
The effect of a zinc, cobalt and selenium soluble glass bolus on the trace element status of extensively grazed sheep over winter
Authors: Kendall N. R. , Jackson D. W. , Mackenzie A. M. , Illingworth D. V. , Gill I. M. , Telfer S. B. 
Published: August 2016

AbstractThe effects of trace element deficiencies in lambs, particularly zinc, copper, cobalt and selenium, include decreased growth rates and increased mortality. However, trace element supplementation of sheep reared under extensive conditions has several logistical problems.Two trials were designed to investigate the effect of a zinc, cobalt and selenium soluble glass bolus on the trace element status of out-wintered ewe lambs. In trial 1 600 8-month-old ewe lambs (500 Scottish Blackface and 100 North Country Cheviots) were allocated to two treatment groups; 300 were treated with a zinc, cobalt and selenium soluble glass bolus (zinc) and 300 were untreated (control). In trial 2, 315 8-month-old Scottish Blackface ewe lambs were allocated to three treatments: 105 were treated with the zinc, cobalt and selenium soluble glass bolus (zinc), 105 were treated with a copper, cobalt and selenium soluble glass bolus (copper) and the remaining 105 were untreated (control). Blood samples were collected immediately prior to giving boluses and again after approximately 4 months. These were assessed for zinc (plasma zinc concentration), cobalt (serum vitamin B12concentration), selenium (erythrocyte glutathione peroxidase activity) and copper status (plasma copper concentration, caeruloplasmin, amine oxidase and superoxide dismutase activity and calculation of the ratio between the caeruloplasmin and plasma copper).The zinc bolus in both trials significantly increased the plasma zinc concentrations (P< 0·001 andP< 0·01 respectively), erythrocyte glutathione peroxidase activities (P< 0·001) and serum vitamin B12concentrations (P< 0·001). The copper bolus also significantly increased the erythrocyte glutathione peroxidase activities (P< 0·001) and serum vitamin B12concentrations (P< 0·001) when compared with the controls but were not significantly different from the zinc group. The copper bolus significantly increased all of the copper status indicators (P< 0·01) when compared with the control and zinc groups. However, in trial 1 when only the zinc and control groups were compared, the zinc bolus significantly increased the ratio (P< 0·001) and serum caeruloplasmin (P< 0·001) and erythrocyte superoxide dismutase (P< 0·01) activities. These responses were not observed in trial 2 with the erythrocyte superoxide dismutase being significantly reduced in the zinc group when compared with the control group (P< 0·001).The zinc, cobalt and selenium soluble glass bolus increased the status of all three trace elements consistently for a period of at least 100 days. The increases of cobalt and selenium status were similar to those achieved using the copper, cobalt and selenium bolus, which also increased the copper status of the sheep.