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Deficits in facial, body movement and vocal emotional processing in autism spectrum disorders
- R. C. M. Philip, H. C. Whalley, A. C. Stanfield, R. Sprengelmeyer, I. M. Santos, A. W. Young, A. P. Atkinson, A. J. Calder, E. C. Johnstone, S. M. Lawrie, J. Hall
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- Journal:
- Psychological Medicine / Volume 40 / Issue 11 / November 2010
- Published online by Cambridge University Press:
- 27 January 2010, pp. 1919-1929
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Background
Previous behavioural and neuroimaging studies of emotion processing in autistic spectrum disorder (ASD) have focused on the use of facial stimuli. To date, however, no studies have examined emotion processing in autism across a broad range of social signals.
MethodThis study addressed this issue by investigating emotion processing in a group of 23 adults with ASD and 23 age- and gender-matched controls. Recognition of basic emotions (‘happiness’, ‘sadness’, ‘anger’, disgust' and ‘fear’) was assessed from facial, body movement and vocal stimuli. The ability to make social judgements (such as approachability) from facial stimuli was also investigated.
ResultsSignificant deficits in emotion recognition were found in the ASD group relative to the control group across all stimulus domains (faces, body movements and voices). These deficits were seen across a range of emotions. The ASD group were also impaired in making social judgements compared to the control group and this correlated with impairments in basic emotion recognition.
ConclusionsThis study demonstrates that there are significant and broad-ranging deficits in emotion processing in ASD present across a range of stimulus domains and in the auditory and visual modality; they cannot therefore be accounted for simply in terms of impairments in face processing or in the visual modality alone. These results identify a core deficit affecting the processing of a wide range of emotional information in ASD, which contributes to the impairments in social function seen in people with this condition.
The risk of leptospirosirs in United Kingdom fish farm workers. Results from a 1981 serological survey
- O. N. Gill, J. D. Coghlan, I. M. Calder
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- Journal:
- Journal of Hygiene / Volume 94 / Issue 1 / February 1985
- Published online by Cambridge University Press:
- 19 October 2009, pp. 81-86
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Less than one per cent of serum samples taken from 257 fish farmers in 1981 had agglutinating antibodies to strains of Leptospira interrogans of serogroup Icterohaemorrhagiae at a titre of 30 or greater. Compared with the results from other serological surveys, this agglutinating antibody prevalence suggests that fish farming does not have a high occupational risk for leptospirosis. Between 1961 and 1981 the incidence in fish farmers was about 33 per 100000 person years at risk. During the same period the incidence in the general adult male population was 0·137 per 100000 person years at risk, so that fish farming had a moderately increased risk of Icterohaemorrhagiae serogroup infection (relative risk = 243). No one particular risk factor within fish farming could be reliably identified and therefore recommendations to reduce the risk can only be general.
The early weaning of pigs IV. Comparisons of levels of antibiotic and sources of protein in diets for pigs weaned at 9 lb. live weight
- I. A. M. Lucas, A. F. C. Calder, H. Smith
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- Journal:
- The Journal of Agricultural Science / Volume 53 / Issue 1 / August 1959
- Published online by Cambridge University Press:
- 27 March 2009, pp. 125-129
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In Exp. 1 groups of piglets weaned at about 9 lb. live weight were fed one of three 29% protein diets up to 26 lb. live weight. These diets A, B and C contained 42, 20 and 0% dried skim milk, 15, 25 and 32% white fish meal and 22, 34 and 47% rolled oat groats, respectively. At 26 lb. all pigs were changed over to a standard 17% protein diet.
The replacement of about one-half of the dried skim milk in diet A with white fish meal and rolled oat groats caused 4% faster growth from 9 to 26 lb. live weight, but the replacement of all the dried skim milk caused growth over the same weight range to be slower by 6%. The quadratic component of these treatment effects was significant at P < 0·0·25. The slower growth with the diet containing no dried skim milk was associated with a lower daily consumption of feed, and the improved growth rate with the intermediate skim milk level was probably associated with an improvement in food conversion efficiency. Treatment differences in food conversion efficiency before 26 lb. live weight, however, were not statistically significant. There were no significant carry-over effects of treatments upon performance from 26 to 50 lb. live weight.
In Exp. 2 piglets weaned at about 9 lb. live weight were fed individually up to 40 lb. live weight. From 9 to 26 lb. antibiotic levels of 22, 45, 67 and 90 mg./lb. feed were compared, but from 26 to 40 lb. all pigs were fed a standard diet containing 18 mg. antibiotic/lb. In diets fed before 26 lb. the antibiotic was a mixture of 3 parts by weight chlortetracycline: 1 part by weight procaine penicillin. From 26 to 40 lb. live weight the antibiotic fed was chlortetracycline.
Before 26 lb. live weight increases in antibiotic level caused average increases of up to 5% in growth rate and 4% in food conversion efficiency. Taken in conjunction with previous results the improvement in growth rate in favour of the highest antibiotic level was significant at P < 0·05.
There were no carry-over effects of antibiotic level on growth rate from 26 to 40 lb., but there was the suggestion of a linear trend whereby each increase in antibiotic level fed before 26 lb. caused a decrease in food conversion efficiency between 26 and 401b. (P = 0·10).
The results are discussed in relation to financial economies which may be made in diets for early weaned pigs.
The interaction between environment and level of feeding* for pigs from weaning to bacon weight
- I. A. M. Lucas, A. F. C. Calder
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- Journal:
- The Journal of Agricultural Science / Volume 46 / Issue 1 / June 1955
- Published online by Cambridge University Press:
- 27 March 2009, pp. 56-77
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1. The rates of growth and efficiencies of food conversion between 45 and 100 lb. live weight of pigs kept to a low plane of feeding were most adversely affected during the winter months by bad housing conditions, wherein the average air temperature was 43° F. On the other hand, this bad housing had no adverse effect upon pigs of a similar size kept to a high plane of feeding.
2. The summer season, with consequently higher environmental temperatures in both good and bad piggeries, only had a significantly beneficial effect upon the rates and efficiencies of growth of pigs of 45–100 lb. live weight kept to a low plane of feeding in a bad piggery. Any effects upon the growth of pigs of similar size kept to a high plane of feeding in either a good or bad piggery or to a low plane of feeding in a good piggery did not approach statistical significance.
3. There was probably some environmental factor other than air temperature or relative humidity which had a beneficial effect on the growth of the pigs kept to a low plane of feeding in the good piggery.
4. It was observed, but not proved, that pigs of 100–200 lb. live weight kept to a high plane of feeding grew rather more efficiently in the bad house than in the good house, despite the higher environmental temperatures in the good house.
5. During the growth period between 45 and 100 lb. live weight the efficiency of food conversion, expressed in pounds t.d.n. required per pound liveweight increase, was better in the well-housed pigs kept to the low plane of feeding than in the highplane pigs housed in either piggery.
6. During the growth period between 100 and 200 lb. live weight the efficiency of food conversion of the well-housed low-plane pigs was significantly better than that for the well-housed high-plane pigs, but was not significantly better than the efficiency of food conversion of the high-plane pigs from the bad piggery.
The response of different types of pigs to varying levels of feeding from weaning to bacon weight, with particular reference to carcass quality
- I. A. M. Lucas, A. F. C. Calder
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- Journal:
- The Journal of Agricultural Science / Volume 47 / Issue 3 / May 1956
- Published online by Cambridge University Press:
- 27 March 2009, pp. 287-323
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1. A review of the literature indicated: (a) A lack of agreement upon whether or not restriction of the plane of feeding from weaning or 100 lb. live weight to bacon weight improves efficiency of food conversion. (b) That a severe restriction of the plane of feeding improves carcass-quality measurements, (c) That a less severe restriction of food intake brings the total growth period within a range more acceptable to the farmer, but only has a small effect in improving carcass quality, (d) That the small benefits to quality from this less severe restriction may be equalled or surpassed by quite small changes in the genetic ‘type’ of pig fed. (e) That there are probably interactions in the response of different ‘types’ of pig to different planes of feeding.
2. Two experiments were undertaken. In Exp. 1 both Large White × Swedish Landrace pigs and Large White × Wessex Saddleback pigs were fed from weaning to bacon weight to one of three planes of feeding. Exp. 2 was very similar in design except for some modifications to planes of feeding and the substitution of Essex Saddleback × Large White pigs in place of the Wessex crosses.
3. In Exp. 1 the planes of feeding, according to our stated definitions in terms of total digestible nutrients consumed daily at different live weights, were: very high during both growing and finishing periods (VH-VH); very high during the growing period but restricted during the finishing period (VH-R); and very low during both growing and finishing periods (VL-VL). In Exp. 2 the planes of feeding were: VH-VH; VH-R, the restriction being slightly more severe than in Exp. 1; and low during both growing and finishing periods (L-L).
4. In Exp. 1 there was no difference in growth rate between breed crosses. Pigs on the VH-R and VL-VL planes were 12 and 88 days older respectively at bacon weight than those fed to the VH-VH plane. In Exp. 2, Landrace crosses grew faster than the Essex crosses on the VH-VH and VH-R planes, but Essex crosses grew faster on the L-L plane. Landrace crosses fed to the VH-R and L-L planes were 11 and 63 days older respectively at bacon weight than others fed to the VH-VH plane. Essex crosses fed to the VH-R and L-L planes were 16 and 53 days older respectively at bacon weight than others fed to the VH-VH plane.
5. In Exp. 1 there was no difference in food-conversion efficiency (f.c.e.) between breed crosses. There was no significant difference in f.c.e. between the VH-VH and VH-R planes, but there was a loss of 14% in F.C.E. on the VL-VL plane. In Exp. 2 the Landrace crosses had better F.C.E.'s than the Essex crosses on the VH-VH and VH-R planes, but Essex crosses were the more efficient on the L-L plane. There was no significant difference in F.C.E. between the VH-VH and VH-R planes for either breed cross, but there were losses in efficiency of 4 and 14% on the L-L plane for the Essex and Landrace crosses respectively.
6. In Exp. 1 the Landrace crosses had less back fat over the shoulder than had the Wessex crosses. Pigs of both crosses fed to the VH-R plane had smaller fat measurements than those fed to the VH-VH plane, but this improvement was only significant for minimum back fat. Landrace crosses also had less fat over the ‘eye’ muscle when fed to the VH-R plane, but this did not apply with the Wessex crosses. The difference in carcass quality attributable to the restricted plane of feeding after 100 lb. live weight was considered to be equalled by the difference between breed crosses. The improvement in carcass-quality measurements between pigs fed to the VH-VH and VL-VL planes surpassed the difference between breed crosses, but the carcasses tended to be soft. However, no data were available on the iodine numbers of the fats.
7. In Exp. 2 the Landrace crosses had less fat over the shoulder and over the eye muscle and smaller minimum back-fat measurements than had the Essex crosses. Pigs of both crosses fed to the VH-R plane had smaller fat measurements than those fed to the VH-VH plane, the difference being significant for shoulder fat and minimum back fat. Again the differences between the effects of these two planes of feeding and between the two breed crosses were considered about equal, and again the difference between breed crosses was surpassed by the difference between the carcass measurements of pigs fed to the VH-VH and L-L planes. In Exp. 2 the effects of planes of feeding upon length of carcass, thickness of streak, percentage fore and percentage middle differed significantly between the two breed crosses.
8. When carcass data from both experiments were compared it was apparent that differences between breeds or strains of bacon-type pigs are likely to be of more importance in the production of high-grade bacon than attempts to alter the conformation by varying the plane of feeding—and thus the growth curve—within the limits acceptable in practice.
9. Although previous evidence indicates that males grow faster than females, there was in Exp. 1 no significant difference in growth rate between the sexes. In Exp. 2 there was again no overall significant sex effect, but during the finishing period females grew faster than males on the VH-VH and VH-R planes, but males grew the faster on the L-L plane. In Exp. 1 there was no significant difference between sexes in F.C.E., but in Exp. 2 males were less efficient than females on the VH-VH and VH-R planes, but were the more efficient on the L-L plane, this interaction again developing principally during the finishing period.
10. In both experiments females had carcasses which were longer, had less fat, larger areas of ‘eye’ muscle and larger hams than males. In both experiments the restricted plane of feeding after 100 lb. live weight reduced the shoulder-fat measurements of females but had no effect on those of males which, being the fatter, had the greatest need of improvement to achieve the highest grade. However, the statistical significance of this interaction was low and it requires confirmation.
11. It is not the intention of the authors that these results should be taken to apply in general to the breed crosses used. The breed crosses were chosen solely as pigs which would differ somewhat in genetic type from each other.
12. The results from these experiments confirmed the indications from the literature which have been noted in paragraph 1 of this summary. The results and some of their implications have been discussed in the text.
The growth of pigs kept to one level of feeding, in two environments, and fed diets with and without an antibiotic
- I. A. M. Lucas, A. F. C. Calder
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- Journal:
- The Journal of Agricultural Science / Volume 46 / Issue 3 / October 1955
- Published online by Cambridge University Press:
- 27 March 2009, pp. 307-319
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1. Pigs housed in both a good and a bad piggery were kept to a medium plane of feeding on diets with and without a procaine penicillin supplement. Antibiotic improved neither efficiency nor rate of growth in either piggery during the period from weaning to 100 lb. live weight, nor from then to slaughter at 200 lb. live weight. The average temperatures during the first half of the experiment were 43 and 51° F. in the bad piggery and in the sleeping pens of the good piggery respectively. During the second half of the experiment these averages were 54 and 58° F. respectively.
2. Between weaning and 100 lb. live weight, pigs housed in the bad piggery grew 6% more slowly and 5% less efficiently than in the good piggery, but although the growth rates fitted in well with previous observations, neither difference was statistically significant in this experiment.
3. Between 100 and 200 lb. live weight pigs housed in the good piggery grew 3% less efficiently than in the bad piggery, but there was no difference in rate of growth. The difference in efficiency was statistically significant.
4. Carcasses from pigs housed in the good piggery were fatter than from pigs housed in the bad piggery. These fatter pigs also had higher killing-out percentages.
5. Although dietary antibiotic supplement had no effect upon growth rates or carcass measurements, it resulted in higher killing-out percentages.
The early weaning of pigs VI. The effects of early weaning and of various growth curves before 50 lb. live weight upon subsequent performance and carcass quality
- I. A. M. Lucas, A. F. C. Calder, H. Smith
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- Journal:
- The Journal of Agricultural Science / Volume 53 / Issue 1 / August 1959
- Published online by Cambridge University Press:
- 27 March 2009, pp. 136-144
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The experiment involved nine litters, each containing four male and female pairs of pigs. At about 10 days of age the four pairs within each litter were randomized one to each of the following treatments. (1) Pigs left with their dams, weaned at 56 days old and then fed ad lib. until they each weighed 50 lb. (2) Pigs weaned at 10 days old and fed ad lib. until they each weighed 50 lb. (3) Pigs weaned at 10 days old, given restricted feed allowances so that they weighed 30 lb. at 56 days old, then fed ad lib. until they each weighed 50 lb. (4) Pigs weaned at 10 days old and given restricted feed allowances so that they weighed 30 lb. at 56 days old and 50 lb. at 90 days old. Between 50 lb. and slaughter at 205 lb. all pigs were kept to the same very high plane of feeding, which was based on live weight. All pigs were individually fed from weaning onwards.
Some further observations upon the effects of varying the plane of feeding for pigs between weaning and bacon weight
- I. A. M. Lucas, I. McDonald, A. F. C. Calder
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- Journal:
- The Journal of Agricultural Science / Volume 54 / Issue 1 / February 1960
- Published online by Cambridge University Press:
- 27 March 2009, pp. 81-99
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Three experiments were carried out to obtain more information upon the effects of varying the plane of feeding for bacon pigs.
Exps. 1 and 2 followed the same 3 × 2 factorial design in which (a) diets were fed with or without procaine penicillin and (b) a comparison was made between very high (VH-VH), high (H-H) and low (L-L) planes of feeding for pigs from about 8 weeks old to slaughter at about 200 lb. live weight. The planes of feeding were defined according to the amount of t.d.n. offered to each pig daily.
For each of these two experiments eight lots of six litter mates were used. One pig from each litter was allocated to each of the six treatments, and although litter mates were housed as a group, all pigs were fed individually in separate compartments.
Exp. 3 was a 2 × 3 × 2 factorial to compare two breeds and three planes of feeding during 2 years. During each year three lots of pure-bred Landrace and three lots of Wessex Saddleback × Large White litter mates were used. Each lot consisted of three gilts and three barrows and one pig of each sex was allocated to each of the three feeding treatments. From the start of the experiment, when the pigs were about 8 weeks old, to about 100 lb. weight, all animals were kept to a very high (VH) plane of feeding. From then to slaughter at about 200 lb. live weight the following planes of feeding were compared: (1) very high plane (VH), (2) increasingly restricted plane (R) and (3) low plane (L). As in Exps. 1 and 2 these planes were denned in terms of t.d.n., and litter mates were housed together but fed individually in separate compartments.
In both Exps. 1 and 2 pigs with procaine penicillin in their feed grew very slightly faster and more efficiently than those not fed antibiotic, but the differences did not reach the 5% level of statistical significance. The feeding of antibiotio did not affect the response of the pigs to variations in the plane of feeding.
In comparison with pigs kept to the VH-VH plane of feeding, pigs kept to the H-H and L-L planes grew 13 and 22% more slowly in Exp. 1, and 11 and 26% more slowly in Exp. 2, but plane of feeding had no effect upon food conversion efficiency in either experiment. These results are for the total experimental period.
In both Exps. 1 and 2 reductions in plane of feeding had no significant effect upon length of carcass or thickness of streak, but they caused increases in killing-out percentage and decreases in all measurements of fat thickness. They also caused increases in the area of ‘eye’ muscle (statistically significant in Exp. 2, but not in Exp. 1) and a lengthening in the shape of the ‘eye’ muscle in the bacon rasher (statistically significant in Exp. 1, but not in Exp. 2).
In Exp. 3 the Wessex crosses grew faster and more efficiently than the Landrace, but these differences were considerably larger during one year than during the other. In comparison to the Landrace, the Wessex-cross carcasses had a tendency to be shorter (P < 0·10) and to have thicker shoulder fats. They also had 1% more ‘fore’ and 1% less ‘ham’.
Compared with pigs kept to the VH-VH plane of feeding, those kept to the VH-R and VH-L planes grew 18 and 36% more slowly, respectively, during the finishing period. Over the total experimental period there was no difference in food conversion efficiency between pigs kept to the VH-VH and VH-R planes, but efficiency was poorer by 4–5% with the VH-L plane. There was no breed × feeding interaction in the data for growth rates or food conversion efficiencies.
In Exp. 3 plane of feeding had no significant effect upon killing-out percentage, shape index of ‘eye’ muscle or thickness of streak. The two lower planes of feeding caused reductions in the average rump fat, fat (1) over the ‘eye’ muscle and in the proportion of ‘middle’ in the carcasses; they also caused increases in the proportion of ‘ham’ in the carcasses.
Other carcass quality data contained significant interactions which complicated their interpretation. The effects of plane of feeding were inconsistent between:
(A) years, for length of carcass, maximum shoulder fat, area of eye muscle and iodine values of the back fat;
(B) breeds, for minimum back fat and percentage ‘fore’;
(C) sexes, for dressing percentage and fat (2) over ‘eye’ muscle;
(D) breeds and years, for dressing percentage;
(E) breeds and sexes, for maximum shoulder fat.
The results of the three experiments have been compared with other data on planes of feeding from Rowett Research Institute. A table has been given showing the probable average effects of using different planes of feeding in preference to a VH-VH plane for pigs to be slaughtered at about 200 lb. live weight. The variability in these effects under different circumstances has been discussed and a note has been made of the relative improvements in carcass quality which can be affected through feeding and through breeding.
Antibiotics and a high level of copper sulphate in rations for growing bacon pigs
- I. A. M. Lucas, A. F. C. Calder
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- Journal:
- The Journal of Agricultural Science / Volume 49 / Issue 2 / August 1957
- Published online by Cambridge University Press:
- 27 March 2009, pp. 184-199
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1. One hundred and sixty-eight pigs were used in four experiments to test the value of including antibiotics and copper sulphate, either as separate supplements or together in rations for growing pigs. Procaine penicillin was added at the rate of 5·36 mg./lb. diet and Aureomycin (in Aurofac 2 A) at 8·03mg/lb. and CuSO4. 5H2O as 0·1% of the diet.
2. During the growing period in Exp. 1, pigs fed diets supplemented with copper sulphate or procaine penicillin grew 9 and 3% faster respectively than the controls. Pigs fed a diet containing both supplements grew 22% faster than the controls. During the finishing period there was an outbreak of virus pneumonia and the within-treatment variability was large. There were no significant differences between treatments during this period, although pigs fed the supplemented diets tended to grow more slowly than the controls. Over the total experimental period pigs fed the diet supplemented only with copper sulphate grow 2% faster than the controls, and those fed the diet supplemented with both procaine penicillin and copper sulphate grew 4% faster than the controls, but these small average improvements were not statistically significant. In Exp. 1 treatment differences in food conversion efficiencies paralleled those for growth rates. Killing-out percentages were higher when pigs were fed the copper-supplemented diets, and lower when procaine penicillin was fed. The area of ‘eye’ muscle was increased by adding procaine penicillin to the diet.
3. During the growing period in Exp. 2, pigs fed diets supplemented with copper sulphate or with both procaine penicillin and copper sulphate grew 8 and 9% faster, respectively, than the controls. The addition of procaine penicillin had no significant effect when added as a single supplement or in conjunction with copper sulphate. During the finishing period pigs fed diets supplemented with copper sulphate, procaine penicillin, or both copper sulphate and procaine penicillin grew 5, 3 and 10% faster, respectively, than the controls, while over the total experimental period they grew 4, 0 and 9% faster, respectively.
4. Some pigs fed the copper-supplemented diets during the growing period in Exp. 2 were fed diets with no copper added over the finishing period. During this latter period the pigs grew at about the same speed as the controls, and significantly more slowly than those pigs which continued to receive copper sulphate. Thus, the average growth rates over the total experimental period were significantly slower by 3–7% when copper was omitted after 100 lb. than when it was fed to the pigs throughout the entire experiment.
5. In Exp. 2, as in Exp. 1, treatment differences in efficiency of food conversion paralleled those for growth rates. A higher rate of growth was always accompanied by an improvement in efficiency of food conversion, with about the same percentage difference between treatments. Indeed, changes in rate of growth were probably dependent upon changes in efficiency of food conversion, since all pigs were fed to the same scale based on live weight.
6. The treatment differences in killing-out percentage and area of eye muscle observed in Exp. 1 were not confirmed in Exp. 2. There were no differences in carcass quality measurements attributable to the treatments imposed in Exp. 2.
7. The livers of pigs fed diets containing copper sulphate during both the growing and finishing periods had, on average, about eighteen times the concentration of copper found in the controls. When the copper sulphate supplement was fed only during the growing period the liver copper concentrations were, on average, about four times those of the controls. However, the variation between the individual values was very large in all groups fed copper sulphate. This variation may have been caused partly by sampling errors if copper is not distributed evenly throughout the liver.
Responses in tissue protein synthesis to sub- and supra- maintenance intake in young growing sheep: comparison of large-dose and continuous-infusion techniques
- G. E. Lobley, Patricia M. Harris, Pat A. Skene, D. Brown, E. Milne, A. G. Calder, Susan E. Anderson, P. J. Garlick, I. Nevison, Alexmary Connell
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- Journal:
- British Journal of Nutrition / Volume 68 / Issue 2 / September 1992
- Published online by Cambridge University Press:
- 09 March 2007, pp. 373-388
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- September 1992
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In ten lambs (average live weight 33 kg), five offered 300 g/d (approximately 0.6 x maintenance; L) and five 900 g/d (1.8 x maintenance; H), tissue protein synthesis was measured by three procedures simultaneously. The techniques involved continuous infusion of [U-14C]phenylalanine and [1-13C]leucine over 7–8 h followed by a terminal large dose of [15N]phenylalanine during the last 30 or 60 min. Rates of protein synthesis were then calculated based on the free amino acid or oxo-acid isotopic activity in either arterial, iliac venous blood or tissue homogenate for the continuous-infusion studies, or on plasma or tissue homogenate for the large-dose procedure. For muscle (> 99%), and to a lesser extent skin (85–93%), effective flood conditions were achieved with the [15N]phenylalanine but were either not established or maintained for liver and tissues of the gastrointestinal tract (< 50%). The large dose of phenylalanine also caused changes in the concentration and isotopic activity of blood leucine and 4-methyl-2-oxo-pentanoate. Based on the assumption that the large-dose procedure yields the closest value for the true rate of protein synthesis (L 1.97%/d, H 2.85%/d) then, for muscle, only values based on the homogenate as precursor gave comparable results for both leucine (L 1.83%/d, H 3.01%/d) and phenylalanine (L 1.67%/d, H 2.71%/d) continuous infusion. The values based on the arterial or venous amino or oxo-acid were significantly less, more so at the lower intake. In contrast, for skin, a tissue dominated by export protein synthesis, values from the large-dose procedure (L 6.37%/d, H 10.98%/d) were similar to those derived with arterial or venous metabolites as precursor (L 5.23 and 6.93%/d, H 9.98 and 11.71%/d for leucine), but much less than those based on homogenate data. Based on the large-dose technique, protein synthesis increased with intake in muscle (P < 0.001), skin (P = 0.009) and liver (26.7 v. 30.5%/d; P = 0.029). The contributions of muscle and skin to total protein synthesis were approximately equal. The incremental efficiency of conversion for muscle of synthesized protein into deposition appeared to be similar to values reported for rodents
Thyroxine, Stilboestrol and Antibiotics in Rations for Castrated Male Pigs
- I. A. M. Lucas, A. F. C. Calder
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- Journal:
- British Journal of Nutrition / Volume 9 / Issue 3 / September 1955
- Published online by Cambridge University Press:
- 09 March 2007, pp. 267-279
- Print publication:
- September 1955
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