scholarly journals Net flux of nutrients across splanchnic tissues in wethers consuming grasses of different sources and physical forms ad libitum

1997 ◽  
Vol 77 (5) ◽  
pp. 769-781 ◽  
Author(s):  
A.L. Goetsch ◽  
A. R. Patil ◽  
D.L. Galloway ◽  
B. Kouakou ◽  
Z.S. Wang ◽  
...  

Crossbred sheep (n 16,8·5 months of age and 33 (SE 0·9) kg) were used in a 21 d experiment (2x2 factorial) to determine effects on net flux of nutrients across the portal-drained viscera (PDV) and liver of ad libitum consumption of bermudagrass (Cynodon dactylon; B) v. ryegrass (Lolium multiflorum)-wheat (Triticum aestivum; RW) hay, coarsely chopped (CC) or finely ground and pelleted (GP). Crude protein concentrations were 86, 81, 113 and 119g/kg and neutral-detergent fibre concentrations were 710, 688, 654 and 672 g/kg (dry matter basis) for B-CC, B-GP, RW-CC and RW-GP respectively. Digestible energy intake (6.0,9.6·, 10·2 and 13·8 W/d) Mered (P < 0·01) with grass source and form, and digestible N intake values were 4·4, 7·0, 8·4 and 14.1 (SEM 0·82) g/d for B-CC, B-GP, RW-CC and RW-GP diets respectively. Consumption of O2 by the PDV (118,165,144 and 155mmol/h) and splanchnic bed (196,273,247 and 266 mmollh for B-CC, B-GP, RW-CC and RW-GP respectively) was greater (P=O·O7) for GP than for CC. The ratio splanchnic heat energy production: digestible energy intake was greater (P=0·06) for B than for RW (0·374,0·300,0·278 and 0·219 for B.CC, B-GP, RW-CC and RW-GP respectively). α-Amino-N release by the PDV (P< 0·01; 11·6, 12·8, 23·0 and 18·7 mmoyh) and uptake by the liver (P=0·07; 15·2, 6·1, 17·0 and 19·3 mmol/h for B-CC, B-GP, RW-CC and RW-GP respectively) were greater for RW than for B. Release of NH3-N by the PDV was greater (P=O·02) for CC than for GP (12·5, 6·2, 15·7 and 8·9 mmol/h), and hepatic urea-N release differed between grass sources (P=O·O3) and physical forms (P=0·07; 22·6, 12·7, 31·4 and mmol/h for B-CC, B-GP, RW-CC and RW-GP respectively). In conclusion, decreases in forage particle size elicited by grinding and pelleting did not affect the difference between grass sources in splanchnic tissue heat energy production relative to digestible energy intake.

1995 ◽  
Vol 61 (1) ◽  
pp. 43-55 ◽  
Author(s):  
A. L. Goetsch ◽  
C. L. Ferrell

AbstractCrossbred wethers (34 (s.e. 0·9) kg), with catheters in a hepatic vein, the portal vein and a mesenteric vein and artery, were offered ad libitum alfalfa (A), bermudagrass (B) or ryegrass-wheat (RW) hay and approximately 0, 200 or 400 g/kg maize (dry matter) to determine influences of maize level on net flux of oxygen and nutrients across the portal-drained viscera (PDV) and liver with different forage sources. Digestible energy intake (MJ/day) was 8·5, 12·0 and 12·8 (s.e. VIS) for A; 4·5, 5·5 and 9·0 (s.e. 0·93) for B; and 9·4, 8·8 and 12·2 (s.e. 0·93) for RW with 0, 200 and 400 g/kg maize, respectively. Splanchnic bed oxygen consumption (mmol/h) was 301, 304 and 322 (s.e. 27·2) for A; 178, 187 and 217 (s.e. 30·0) for B; and 226, 133 and 233 (s.e. 19·0) for RW with 0, 200 and 400 g/kg maize, respectively. Increasing dietary maize level linearly increased (P < 0·05) PDV release of alpha-amino nitrogen with B (5, 9 and 14 mmol/h) but not with A or RW. Dietary maize level did not consistently alter PDV or hepatic net flux of urea or ammonia nitrogen, suggesting that changes in ruminally fermentable organic matter from diets offered ad libitum, presumably induced by varying dietary concentrate level, may not alter nitrogen recycling when forage is 86 g/kg or greater in crude protein. Propionate release by the PDV and hepatic uptake increased linearly (P < 0·08) as maize level in A and B diets increased, although increasing dietary maize level did not significantly alter PDV, hepatic or splanchnic bed net flux of glucose regardless of forage source. Nevertheless, glucose concentration in arterial blood with A and RW increased linearly fP < 0·05) with increasing maize level, suggesting increased peripheral glucose availability. In conclusion, the potential to decrease energy consumption by splanchnic tissues relative to digestible energy intake by dietary inclusion of maize, thereby increasing the proportion of absorbed energy available to extra-splanchnic tissues, may be greater for low-quality forage than for forage of moderate or high quality and for moderate v. low dietary levels of maize with low-quality forage.


1983 ◽  
Vol 36 (2) ◽  
pp. 193-199 ◽  
Author(s):  
R. G. Campbell ◽  
M. R. Taverner ◽  
D. M. Curic

ABSTRACTForty-two pigs representing equal numbers of entire males and females were used to study the effects on the performance and body composition of four restricted levels of feeding (14·5, 20·3, 24·9 and 29·4 MJ digestible energy per day), and of offering the same diet (14·5 MJ digestible energy per kg and 210 g crude protein per kg) ad libitum between 20 and 45 kg live weight.Over the four restricted feeding treatments there were no significant differences between the sexes for the performance and body composition of four restricted levels of feeding (14·5, 20·3, 24·9 and 29·4 MJ digestible energy per day), and of offering the same diet (14·5 MJ digestible energy per kg and 210 g crude protein per kg) ad libitum between 20 and 45 kg live weight.Although ad libitum energy intake was the same for both sexes (34·2 MJ digestible energy per day), raising digestible energy intake from that provided by the highest restricted feeding treatment (29·4 MJ/day) to ad libitum resulted in marked differences between the sexes for performance and body composition.For males, raising digestible energy intake from 29·3 to 34·2 MJ/day improved the rate of live-weight gain and protein deposition by 0·15 and 0·10 respectively but had no further effect on food conversion ratio or body fat. The same increase in digestible energy intake for females improved growth rate by only 0·065, had no further effect on the rate of protein deposition but increased markedly food conversion ratio and body fat.


1966 ◽  
Vol 17 (6) ◽  
pp. 933 ◽  
Author(s):  
RH Weston

Intravenous acetate tolerance tests were conducted on sheep offered chopped lucerne hay at six levels of intake, a ground and pelleted mixture of lucerne hay, maize, and peanut meal at two levels, and a low quality roughage ad libitum. The rate of disappearance of acetate injected intravenously increased with increase in the levels of both feed intake and digestible energy intake. There was no difference between diets in the rate of disappearance when the diets provided similar amounts of digestible energy. Changes in rate of disappearance occurred within 7 days of changes in level of feeding. It was concluded that care should be exercised in interpreting differences between diets in acetate tolerance when the diets provide widely differing quantities of digestible energy.


2017 ◽  
Vol 57 (1) ◽  
pp. 96 ◽  
Author(s):  
Joshua Philp ◽  
Adam M. Komarek ◽  
Sarah J. Pain ◽  
William Bellotti

Small mixed farming systems in developing economies often rely on compensatory growth to recover livestock weight lost during seasonal feed shortages; however, deficit feed management may continue to affect the capacity of livestock to efficiently use feeds even after adequate feeding has resumed. Accordingly, we compared the difference in liveweight gain and feed utilisation over time in Tan weaner sheep in western China, during a period of ad libitum compensatory feeding after alternative feed deficit scenarios. During the feed deficit period, sheep were offered, at 80% maintenance requirements, corn straw, corn grain and lucerne hay in a respective ratio of either 80 : 20 : 0 (S1 ration: metabolisable energy = 7 MJ/kg DM, crude protein = 40 g/kg DM) or 55 : 20 : 25 (S2 ration: metabolisable energy = 8 MJ/kg DM, crude protein = 65 g/kg DM) for 20 days. All sheep were then offered an ad libitum supply of the S2 ration for a further 20 days, during which DM digestibility (DMD), energy intake and liveweight was measured and compared at 5-day intervals. Results indicated that sheep previously fed the S1 ration were not able to digest as much of the ad libitum S2 ration as those previously fed the S2 ration, experiencing significantly lower DMD, energy intake and average daily weight gain. The difference in the effect of the two restrictive feeding treatments on the digestibility of the ad libitum S2 ration gradually decreased over time, indicative of a recovery adaptation during ad libitum feeding period. The rate of DMD recovery post-realimentation was greater in the S1 sheep, likely due to their significantly lower DMD values immediately following underfeeding. We concluded that the comparatively higher nutritive value of the S2 ration sustained rumen digestive function throughout the restrictive feeding period, permitting sheep to commence re-feeding under conditions that are more favourable. Additionally, it is evident that reliance on livestock winter rations typical in western China, as expressed by the S1 ration, degraded ruminant digestive conditions to such an extent that feed was used with reduced efficiency even after being supplied in adequate quantities.


1967 ◽  
Vol 9 (2) ◽  
pp. 141-148 ◽  
Author(s):  
D. J. A. Cole ◽  
J. E. Duckworth ◽  
W. Holmes

1. The voluntary feed intakes of pigs fed on diets having calculated digestible energy contents of 2,970, 3,356, 3,630 and 3,910 kcal/kg. dry matter were measured over four periods from 38 to 105 kg. live-weight.2. The pigs achieved similar daily digestible energy intakes regardless of the digestible energy content of the diet.3. When housed in metabolism crates pigs ate less than when housed in holding pens and the difference was greater than would be expected solely from the reduced exercise of the pigs in crates.4. Daily digestible energy intake was 575 kcal/kg. live-weight 0.675 when the pigs were in holding pens. The daily digestible energy intake of pigs in metabolism crates increased less with live-weight.5. The use of metabolism crates to obtain digestibility coefficients and values for nitrogen retention to be applied to animals housed under other conditions is discussed in relation to the differences found in apparent digestibility coefficients, feed intake and growth rates between pigs in crates and in holding pens.


2007 ◽  
Vol 98 (3) ◽  
pp. 636-640 ◽  
Author(s):  
C. Jeya K. Henry ◽  
Helen J. Lightowler ◽  
Caroline M. Strik

The aim of the present study was to investigate the effects of long-term intervention of low-glycaemic-index (GI) v. high-GI breakfasts on energy and macronutrient intakes in children aged 8–11 years. Preadolescent children were assigned to one of two groups in a random cross-over design. Each group was given low-GI and high-GI breakfasts on two non-consecutive days per week for 10 weeks per breakfast type. Each breakfast provided approximately 1273 kJ (300 kcal) and was closely matched for macronutrient and dietary fibre content. Subsequent food intake at an ad libitum buffet lunch was recorded and daily energy and macronutrient intakes were measured by 24 h recall and 3 d food diaries. There was a tendency towards a reduced energy intake at lunch following the low-GI breakfast compared with the high-GI breakfast, although the mean difference of 75 kJ (18 kcal) was not significant (P = 0·406). In particular, there was a trend towards a reduced energy intake in the low-GI arm compared with the high-GI arm among boys. In addition, data from the 3 d food diaries showed that there was a tendency towards a reduced energy intake during the low-GI compared with the high-GI study period. In conclusion, although the difference in energy intake following the low-GI and high-GI breakfasts was not statistically significant, the reduced energy intake following the low-GI breakfast is encouraging. Both dietary fibre and carbohydrate type may affect GI, thus their potential and relative modulating effect on appetite requires further investigation.


1983 ◽  
Vol 37 (1) ◽  
pp. 119-123 ◽  
Author(s):  
G. G. Partridge ◽  
S. J. Allan

ABSTRACTAn experiment was performed to examine the effects of feeding four concentrations of crude protein in the diet to lactating rabbits. Diets A, B, C and D contained 173, 181, 224 and 243 g crude protein per kg dry matter respectively. Each diet was offered at one of two feeding levels: H (330 g/day) or L (280 g/day) with three replicates in each of the eight treatment groups. Milk production and nitrogen balance were measured over a 28-day lactation.Although dry-matter intakes on feeding level H were significantly higher than those on feeding level L the difference diminished as the crude protein concentration decreased. The effect of crude protein intake on doe milk production was estimated therefore by regression analysis with digestible energy intake as a covariate. Both crude protein intake and digestible energy intake alone had significant effects (P < 0·001) on daily milk production and there was also a significant effect (P < 0·05) of crude protein intake after fitting digestible energy intake. Overall the equation was:Milk production (g/day) =17·61 + 0·985 crude protein intake (g/day) + 30·3 digestible energy intake (MJ/day).(±0·448) (±14·8)The relationship between digested nitrogen and nitrogen output as milk was also examined by regression analysis with digestible energy intake as a covariate. This equation was:Nitrogen output in milk (g/day) =0·438 + 0·164 digested nitrogen (g/day) + 0·572 digestible energy intake (MJ/day).(±0·068) (±0·294)The practical implications of feeding high levels of crude protein in the diet to increase milk production and pup weaning weight are discussed.


1995 ◽  
Vol 46 (2) ◽  
pp. 285 ◽  
Author(s):  
MT Skorupski ◽  
DJ Garrick ◽  
HT Blair ◽  
WC Smith

A computer model simulating life cycle production of a breeding sow and growth performance of her offspring was developed to estimate economic values of reproduction and growth performance traits. A biological growth model, simulating the digestion and metabolism of dietary nitrogen in growing pigs (20 to 85 kg), was part of the life cycle model. The growth model was based on the linear/plateau relationship between daily protein deposition and digestible energy intake. A farrow-to-finish production system, with slaughter pigs marketed at fixed liveweights, was simulated. Input variables were: gilt age at first oestrus, weaning to oestrus interval, number of pigs born alive per litter, and pre-weaning mortality for each parity. Economic inputs included prices of feed ingredients, carcass returns and non-feed costs. The upper limit to body protein deposition rate, mean daily ad libitum digestible energy intake and minimum lipid to protein deposition ratio were assumed the major genetic determinants of pig growth. The model output included average daily gain, ad libitum daily feed intake, backfat thickness, and life cycle reproductive performance and profit. The combined life cycle profit was expressed in the form of an Annualized Present Value. Life cycle profit was calculated for a range of simulated pig genotypes.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Gabriel Giacobone ◽  
Maria Victoria Tiscornia ◽  
Leila Guarnieri ◽  
Luciana Castronuovo ◽  
Sally Mackay ◽  
...  

Abstract Background Food cost and affordability is one of the main barriers to improve the nutritional quality of diets of the population. However, in Argentina, where over 60% of adults and 40% of children and adolescents are overweight or obese, little is known about the difference in cost and affordability of healthier diets compared to ordinary, less healthy ones. Methods We implemented the “optimal approach” proposed by the International Network for Food and Obesity/non-communicable diseases Research, Monitoring and Action Support (INFORMAS). We modelled the current diet and two types of healthy diets, one equal in energy with the current diet and one 6.3% lower in energy by linear programming. Cost estimations were performed by collecting food product prices and running a Monte Carlo simulation (10,000 iterations) to obtain a range of costs for each model diet. Affordability was measured as the percentage contribution of diet cost vs. average household income in average, poor and extremely poor households and by income deciles. Results On average, households must spend 32% more money on food to ensure equal energy intake from a healthy diet than from a current model diet. When the energy intake target was reduced by 6.3%, the difference in cost was 22%. There are no reasonably likely situations in which any of these healthy diets could cost less or the same than the current unhealthier one. Over 50% of households would be unable to afford the modelled healthy diets, while 40% could not afford the current diet. Conclusions Differential cost and affordability of healthy vs. unhealthy diets are germane to the design of effective public policies to reduce obesity and NCDs in Argentina. It is necessary to implement urgent measures to transform the obesogenic environment, making healthier products more affordable, available and desirable, and discouraging consumption of nutrient-poor, energy-rich foods.


2021 ◽  
pp. 1-51
Author(s):  
Yan Yin Phoi ◽  
Michelle Rogers ◽  
Maxine P. Bonham ◽  
Jillian Dorrian ◽  
Alison M. Coates

Abstract Circadian rhythms, metabolic processes, and dietary intake are inextricably linked. Timing of food intake is a modifiable temporal cue for the circadian system and may be influenced by numerous factors, including individual chronotype—an indicator of an individual’s circadian rhythm in relation to the light-dark cycle. This scoping review examines temporal patterns of eating across chronotypes and assesses tools that have been used to collect data on temporal patterns of eating and chronotype. A systematic search identified thirty-six studies in which aspects of temporal patterns of eating including meal timings; meal skipping; energy distribution across the day; meal frequency; time interval between meals, or meals and wake/sleep times; midpoint of food/energy intake; meal regularity; and duration of eating window were presented in relation to chronotype. Findings indicate that compared to morning chronotypes, evening chronotypes tend to skip meals more frequently, have later mealtimes, and distribute greater energy intake towards later times of the day. More studies should explore the difference in meal regularity and duration of eating window amongst chronotypes. Currently, tools used in collecting data on chronotype and temporal patterns of eating are varied, limiting the direct comparison of findings between studies. Development of a standardised assessment tool will allow future studies to confidently compare findings to inform the development and assessment of guidelines that provide recommendations on temporal patterns of eating for optimal health.


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