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Principles of the Future Education Strategy
- J. Goford, C.S. Bellis, C.D. Bykerk, S.A. Carne, S. Creedon, C.D. Daykin, N.J. Dumbreck, D.G.R. Ferguson, E.M. Goodwin, P.H. Grace, N.S. Henderson, P.N. Thornton
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- Journal:
- British Actuarial Journal / Volume 7 / Issue 2 / 01 June 2001
- Published online by Cambridge University Press:
- 10 June 2011, pp. 221-240
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The paper explores the framework for the development of actuarial education in the future. The main aims are to broaden the profession while maintaining standards and to achieve global qualifications by working with other actuarial bodies. The suggested way forward would mean several changes from existing practice.
The response of growing pigs to amino acids as influenced by environmental temperature: tryptophan
- N.S. Ferguson, R.M. Gous
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- Journal:
- Animal Science / Volume 74 / Issue 1 / February 2002
- Published online by Cambridge University Press:
- 18 August 2016, pp. 103-110
- Print publication:
- February 2002
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An experiment was performed to measure the response of young pigs to dietary tryptophan (TRP) concentrations and environmental temperatures. Seventy-two entire male Large White ✕ Landrace pigs were assigned to one of six dietary treatments (2·90 (T1), 2·46 (T2), 2·01 (T3), 1·57 (T4), 1·12 (T5) g/kg and T5 + supplemented TRP (T6)) and one of three temperature treatments (20, 25 and 30°C) at a mean starting live weight of 14·38 (s.e. 0·201)kg. Animals were given ad libitum access to food until a final weight of 26·42 (s.e. 0·479) kg. There were no significant interactions between temperature and dietary TRP on any production variable. There was a significant (P < 0·05) quadratic improvement in the rate of live-weight growth (ADG) as the concentration of dietary TRP increased and as the temperature decreased. However, the response to increasing dietary TRP was independent of the environmental temperature. Maximum ADG was attained on T2 (0·498 (s.e. 0·023) kg/day) and at 20ºC (0·412 (s.e. 0·024) kg/day). Final live weight was a significant (P < 0·001) covariate for ADG and food intake (FI) responses. With TRP as a precursor for serotonin, a neurotransmitter that regulates appetite, it was anticipated that food intake would be affected with decreasing dietary TRP levels. However, there was no response in daily food intake to decreasing TRP concentration. This lack of response in appetite to dietary TRP may have been a result of an increasing TRP to large neutral amino acid ratio, which is known to correlate with an increase in serotonin synthesis. Total heat loss followed a similar response to FI. The gain per unit of food consumed was significantly (P < 0·001) reduced as the TRP content of the diet was decreased. The most efficient treatments were T1 (506 (s.e. 1·90) g gain per kg food) and T2 (495 (s.e. 23·2) g gain per kg food) while the worst was T5 (237 (s.e. 22·3) g gain per kg food). There were significant quadratic responses to dietary TRP in protein content of the empty body (P < 0·05) and the rate of protein retention (PR) (P < 001) but only PR was affected by temperature (P < 001). Both temperature (P < 0·05) and dietary TRP (P < 0·001) had a significant effect on the lipid content of the body but only temperature affected the rate of lipid retention, with a significantly (P < 0·001) lower rate at 30 oC. The efficiency of TRP utilization improved with increasing temperature. It was lowest at 20ºC (0·60 g TRP per kg protein) and highest at 30ºC (0·86 g/kg), while the mean efficiency for pigs between 14 and 26 kg live weight, at thermoneutrality (25°C), was close to 0·71 g/kg.
The effect of stocking density on the responses of growing pigs to dietary lysine
- N.S. Ferguson, G. Lavers, R.M. Gous
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- Journal:
- Animal Science / Volume 73 / Issue 3 / December 2001
- Published online by Cambridge University Press:
- 18 August 2016, pp. 459-469
- Print publication:
- December 2001
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An experiment was conducted to measure the effects of stocking density (increased number of pigs per pen) on lysine requirements of pigs grown from 25 to 60 kg live weight. Two hundred and sixty-four female Large White ✕ Landrace pigs were assigned at 25 kg to one of four dietary lysine treatments (13·3 (L1); 11·4 (L2); 9·5 (L3) and 7·6 (L4) g/kg) and either seven or 13 pigs per pen (or 1 0 and 0·5 m2 per pig, respectively). An additional treatment of one pig per pen (20 m2 per pig) was included to compare the responses of solitary- versus group-penned pigs. Animals were given ad libitum access to dietary treatments from a mean pen starting weight of 261 (s.e. 0·35) kg to a mean pen finishing weight of 63·4 (s.e. 0·61) kg live weight. There were no significant interactions between dietary lysine content and floor space per pig on food intake (FI), average daily growth rate (ADG), the amount of food per unit of gain (FCR) and the rate of protein retention (PR). Significant interactions were evident for body composition and the rate of lipid retention (LR). Over the weight range 25 to 40 kg there were significant differences in FI (P < 0·05) and FCR (P < 0·001) between dietary lysine treatments but most of these differences had disappeared over the 40 to 60 kg live weight. Individually penned animals had significantly higher (P < 0·05) FI and ADG than group-penned animals. However, there were no differences between seven and 13 pig per pen treatments. Stocking density had no effect on LR or body protein content but did cause a significant reduction in PR (P < 0·001) and an increase in body lipid content (P < 0·05) as the number of pigs per pen increased from seven to 13. Lysine requirements (expressed in g/day) therefore could be seen to be reduced with increasing stocking density. However, as lysine intake was reduced in group-penned animals, the reduced daily requirement does not necessarily warrant a reduction in the lysine content of the food. Feeding according to the requirements for maximum PR will still produce the best carcass and growth performance irrespective of the group size. The improvement in PR associated with higher dietary nutrient levels did not completely offset the adverse physiological effects of higher stocking density but may partly counteract the effect of reduced lysine intake. However, there were indications that feeding crowded pigs a lower dietary lysine concentration may not further reduce the already diminished protein (lysine) growth rate. An additional experiment was performed to test whether the number of feeder bins may have constrained food intake and therefore growth in group-penned animals. The results of this experiment showed that the number of bins had no significant effect on FI, ADG and FCR in group-penned pigs, and therefore a single feeder bin was not considered a constraining factor in pigs housed with limited floor space.
The response of growing pigs to amino acids as influenced by environmental temperature. 1. Threonine
- N.S. Ferguson, G.A. Arnold, G. Lavers, R.M. Gous
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- Journal:
- Animal Science / Volume 70 / Issue 2 / April 2000
- Published online by Cambridge University Press:
- 18 August 2016, pp. 287-297
- Print publication:
- April 2000
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Two 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 response of growing pigs to amino acids as influenced by environmental temperature. 2. Lysine
- N.S. Ferguson, G.A. Arnold, G. Lavers, R.M. Gous
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- Journal:
- Animal Science / Volume 70 / Issue 2 / April 2000
- Published online by Cambridge University Press:
- 18 August 2016, pp. 299-306
- Print publication:
- April 2000
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Two experiments were conducted to measure the effects of a range of dietary lysine 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 lysine treatments (13·8 (L1), 11·8 (L2), 9·6 (L3), 7·6 (L4), 5·6 (L5) g/kg and L5 + supplemented lysine (L6)) 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 differences in the rates of growth between dietary and temperature treatments with the highest gains on L2 (0·597 (s.e. 0·020) kg/day) and at 18°C (0·549 (s.e. 0·018) kg/day). Food intake (FI) increased significantly (P < 0·001) with decreasing lysine content, reached a maximum (L4) and then declined (L5). An increase in the supply of lysine in the diet resulted in significant increases (P < 0·001) in the gain per unit of food (FCE). There was an indication (P < 0·10) that the response in FCE to dietary lysine was dependent on the temperature, with maximum FCE being obtained at 22°C on LI (647 (s.e. 18·5) g gain per kg food). Dietary treatment had a significant effect (P < 0·001) on both the rate of protein (PR) and lipid deposition (LR) irrespective of the temperature. There was a 0·60 reduction in PR and a 1·36 increase in LR in pigs given L5 compared with those given L1. Similar trends occurred in the empty body protein and lipid contents at 25 kg live weight. Both temperature and dietary lysine levels had a significant (P < 0·05) effect on total heat loss (THL). The response in THL was similar to that observed in FI. The efficiency of lysine utilization at 22°C was significantly (P < 0·05) higher than at the remaining temperatures. The mean efficiency for pigs between 13 kg and 25 kg live weight was 0·64 (s.e. 0·05). In general, growth and food intake responses to dietary lysine level were independent of environmental temperature.