Effect of protein, fat, carbohydrate and fibre on gastrointestinal peptide release in humans

Short-term regulation of food intake controls what, when and how much we eat within a single day or a meal. This regulation results from an integrated response to neural and humoral signals that originate from the brain, gastrointestinal (GI) tract and adipose tissue. In the GI tract, multiple sites including the stomach, duodenum, distal small intestine, colon, and pancreas are involved in this process. Ingested food evokes satiety by mechanical stimulation and by release of peptides in the GI tract. The intestine in particular plays a key role in satiety through various peptides secreted in response to food. Many of the intestinal peptides inhibit also gastric emptying thus enhancing gastric mechanoreceptor stimulation. In this review, the current knowledge about the effects of different macronutrients and fibre on the release of GI satiety-related peptides in humans is discussed.     

Effect of repeated regrouping and relocation on behaviour of steers

To investigate the effect of repeated regrouping and relocation (R&R) on behaviour of steers, 72 Holstein–Friesian (14-month-old; 441 ± 3.2 kg) steers were assigned to either control (n = 30; C) or regrouped (n = 42; R) treatments and housed six per pen in 12 pens. The R steers were exposed to six R&R over 84 days. New pen cohorts were allowed to stabilise for 14 days and none of the R steers were allowed to share the same pen or pen mates, where or with whom, they were previously housed. Control steers were housed in the same pen with the same pen mates. Each steer was marked on its back with an individual identification code. Twelve cameras were used to observe and record behaviour for each pen allowing observation of all individual steers continuously for a week following each R&R. The following behaviours were recorded for each steer: lying, standing, eating, drinking, head-to-head contact with another animal while not eating, head contact with the body of another animal and bodily contact with none, one, two or three steers. Behaviour was observed by instantaneous scan sampling after each R&R, at 2 min intervals for 2 h on day 1; at further 20 min intervals on days 1 and 2; and at 120 min intervals from day 3 to 7. Where appropriate, the % of time spent in each behaviour was calculated from the data on total counts in each behavioural category. The total count data were analysed by χ²-statistics for all behavioural categories. Steers were weighed before each R&R. Average daily gain from day 0 to 84 was analysed by ANOVA. During the first 2 h observation period following mixing, R steers displayed a greater (P < 0.05) % of time standing (following the first to sixth R&R), eating (first to fourth and sixth R&R) and drinking (first, third and fourth R&R) than control steers. In the 20 min observational period, a greater % (P < 0.05) of time was spent standing, eating and drinking in R than in C steers following each R&R. In the 120 min observation period, R steers spent a greater (P < 0.05) % of time lying with less body contact behaviours than C steers, and these findings increased in the fourth, fifth and sixth R&R. These data suggest that there was partial adaptation to repeated R&R at the first two R&R followed by complete adaptation at the third and subsequent R&R, with no detrimental effect on animal performance.     

Contribution of rumen protozoa to fibre degradation and cellulase activity in vitro

Abstract The contribution of ciliates to rumen fermentation was estimated by determination of overall fibre degradation and cellulase activities (determined as carboxymethylcellulase activity) in faunated and defaunated 'artificial rumen' cultures. Experiments performed at loading rates of 22.5 and 35 g per liter per day of a grass-grain substrate revealed that fibre degradation was significantly lower in the absence of ciliates only at the high loading rate. This effect of defaunation was smaller at dilution rates below 1.7 fermenter volume turnovers per day. Bacterial numbers were higher in all experiments after removal of ciliates. Fractionation studies demonstrated that ciliates accounted for 19–28% of the total cellulase activity in faunated cultures fed on filter paper cellulose.     

Effects of fibre concentration of diets consisting of hay and slowly degradable concentrate on ruminal fermentation and digesta particle size in mid-lactation dairy cows

The objective of this study was to investigate the intestinal microbiota of growing kittens fed moderate- or high-protein diets using DNA-based qualitative and quantitative techniques. Kittens were weaned to a high-protein (HP; n = 7) or moderate-protein (MP; n = 10) diet at 8 weeks of age. Fresh faecal samples were collected at 8, 12, and 16 weeks of age. DNA was extracted and quantitative PCR used to quantify Bifidobacterium, Lactobacillus, Clostridium perfringens, and Escherichia coli concentrations. Denaturing gradient gel electrophoresis was performed to create a dendrogram and unrooted trees using Bionumerics 5.0 to identify similarity due to litter, age, or diet. Kittens fed HP had lower (p = 0.02) Bifidobacteria and Lactobacillus counts than MP-fed kittens. E. coli was lower (p = 0.02) in HP-fed kittens and tended to be affected by age (p = 0.09). Kittens were clustered by litter at 8 weeks of age, and then clustered by diet at 12 and 16 weeks of age. Our data suggest that faecal microbiota of growing kittens change after weaning and that dietary protein concentration affects E. coli, Bifidobacterium, and Lactobacillus populations. The relevance of these data in terms of intestinal health and disease remain to be determined and justifies further study.     

Effects of stochastic food deprivation on energy budget,body mass and activity in Swiss mice

When small animals are faced with an unpredictable food supply,they can adapt by altering different components of their energy budget such as energy intake,metabolic rate,rate of non-shivering thermogenesis(NST)or behaviour.The present study examined the effect of stochastic food deprivation(FD)on body mass,food intake,resting metabolic rate(RMR),NST and behaviour in male Swiss mice.During a period of 4 weeks' FD,animals were fed ad libitum for a randomly assigned 4 days each week,but were deprived of food ...     

Stress, behaviour and reproductive performance in female cattle and pigs

Female farm animals are exposed to a great variety of environmental and management related stressors. As a consequence, their reproductive and maternal abilities may be compromised through mechanisms acting on the hypothalamic, pituitary, ovarian and uterine function. Responses to short- and long-term stressors may differ as short-term stressors often fail to affect reproduction or even may have stimulatory effects. Thus, the stress response induces diverse neuroendocrine reactions that can either increase or decrease the probability of an animal reproducing depending on the specific situation. The aim of the present review is to summarise the current knowledge on the stress concept and its implications on behaviour and reproductive performance in cows and female pigs as phenomena reported in laboratory animals are unable to explain all effects encountered in domesticated farm animals.     

The effects of food and density on the nocturnal behaviour ofArion ater andAriolimax columbianus (Pulmonata: Stylommatophora)

The effects of food supply and population density on the nocturnal behaviour of Arion ater and Ariolimax columbianus were investigated. Density did not significantly affect A. ater's level of activity or short-term movement, resting, or feeding. A. columbianus was more active and moved, rested, and fed more frequently when slug density was high. A. ater foraged and rested more often, but fed less when good food was unavailable. Ariolimax's only response to the food regime was to feed more when good food was available. Seasonal changes in the level of activity and behaviour of Arion were evident, whereas Ariolimax's activity and behavioural repertoire were not similarly affected. Arion ater's nightly activity appeared to be mainly food oriented, while Ariolimax columbianus seemed most responsive to slug density during its nocturnal activity periods.     

Effects of floor-feeding and the presence of a foraging substrate on the behaviour and stress physiological response of individually housed gilts

Both restricted feeding and barren housing have a negative influence on sow welfare. The aim of this study was to test whether sows that have to search for their feed in a substrate on the floor show less stereotyped (and other abnormal) behaviour and have a lower physiological stress response. In three batches, 96 gilts were housed individually in two rooms in 3.1 m² pens with 1.9 m² solid floor. In a 2×2 factorial design either wood shavings (S) or no substrate (NS) were provided on the floor, and 900 g of feed was provided twice daily (06:30 and 15:00 h) either in a trough (T) or on the floor (F). In weeks 8–12, behaviour was scan-sampled once in the periods 07:00–09:00 h (P1), 10:00–12:00 h (P2), and 13:00–15:00 h (P3). Data from the 5 weeks were pooled per animal. Video recordings (24 h) in week 12 or 13 were scan-sampled for ‘standing’. Saliva samples were taken in week 11 at 2 h intervals during 24 h and measured for cortisol. Spontaneously voided morning-urine was sampled in weeks 2, 7 and 12 or 13 for determination of ratios of adrenaline (A) and noradrenaline (NA) with creatinine (CR). Most effects that were found were due to substrate presence. Main findings were that compared with S-animals, NS-animals stood more during the dark period (4.8% versus 3.0%; P<0.05) and showed more (visible) oral behaviour in P1 (56.8% versus 47.6%; P<0.05), P2 (35.8% versus 30.8%; tendency) and P3 (44.1% versus 33.8%; P<0.05). This included more sham chewing in P1 (tendency), P2 and P3, more pen manipulation in P3, and more other oral behaviour (e.g. teeth grinding) in P1 (tendency) and P2. They had higher cortisol levels before feeding (peaks) and in the early evening (24 h average: 1.49 ng/ml versus 1.02 ng/ml; P<0.05) and higher NA/CR ratios in weeks 7 (tendency) and 12 (5.5 ng/mg versus 3.7 ng/mg; P<0.05). No treatment effects were found on A/CR ratios. Substantial interactive effects of feeding method and substrate were only found in floor manipulation. In all three periods NS-T-animals manipulated the floor less than other animals, probably because they had no attraction to the floor and were not rewarded for searching. Results imply that the presence of a substrate on the floor improves welfare, whereas provision of feed in the substrate in order to stimulate foraging behaviour is of less importance.     

Methods of collection for salivary cortisol measurement in dogs

Salivary cortisol has been increasingly used as a measure of stress response in studies of welfare, reaction to stress and human-animal interactions in dogs and other species. While it can be a very useful measure, there are a number of saliva collection issues made evident through studies in the human and animal fields which have not been investigated in the canine species. Collection materials and the volume of saliva that is collected; the use of salivary stimulants; and the effect of food contamination can all dramatically impact cortisol measurement, leading to spurious results. In order to further examine the limitations of the collection method and the effects of collection material and salivary stimulant on salivary cortisol levels, a series of clinical, in vitro and in vivo studies were performed. It was found that there is a large amount of inter- and intra-individual variation in salivary cortisol measurement. Beef flavoring of collection materials leads to unpredictable variability in salivary cortisol concentration. Using salivary stimulants such as citric acid also has the potential to affect cortisol concentration measurement in saliva. Hydrocellulose appears to be a useful collection material for salivary cortisol determination. Recommendations for collection materials and use of salivary stimulants are presented.     

The effect of feeder type and change of feeder type on growing and finishing pig performance and behaviour

Reduced feed intake and hence lower growth rates commonly occur when the environment of the pig changes, e.g. at weaning and when pigs are moved from growing accommodation to finishing accommodation. It is hypothesised that if environmental factors, such as feeder type, remain the same in the weaning and finishing accommodation this ‘growth check’ may be reduced. A total of 640 pigs in 32 pens of 20 pigs per pen were used to investigate the effects of two feeder types and changing or not changing the feeder type at 10 weeks of age on growth performance and behaviour in the periods from 4 to 10, 10 to finish (22) and from 4 to finish (22) weeks of age, respectively. The two feeder types tested were a ‘wet and dry’ single-space (S) feeder and a ‘dry’ multi-space feeder (M).In the period 4–10 weeks of age feeder type had no significant effect on growth performance though pigs on the ‘dry’ multi-space feeder tended to exhibit significantly better feed efficiency from 4 to 7 weeks of age. In the first week after changing accommodation the growth rate of pigs on all treatments was depressed (compared to the last 3 weeks of the grower period) and was reduced a further 60 g/day when the feeder type was changed. However, the “feeder” effect was transitory and had no effect on overall finisher performance except for pigs changed from a ‘dry’ multi-space feeder to ‘wet and dry’ single-spaced feeder. These animals had significantly faster growth rate over the finisher phase (P<0.05, 886 g/day) and between 4 weeks of age and finish (P<0.05, 730 g/day) than pigs on all other treatments. Feeder treatment had no significant effect on feed intake or feed efficiency in the finisher period or overall from wean to finish. Similarly, the treatments had no effect on the variation in growth rate. Behavioural observations showed that the average number of pigs at the feeder during the finishing period was significantly higher when feed was offered from treatment M–S (1.19 (freq/30 s), P<0.001). In conclusion, the present results suggest that, a change in feeder type, from a ‘dry’ multi-space feeder in growing accommodation to a ‘wet and dry’ single-space feeder in finishing accommodation appears to stimulate improved growth performance in the early finishing period and overall from weaning to finish.     

Influence of dietary pattern,physical activity,and I148M PNPLA3 on steatosis severity in at-risk adolescents

Evidence relating dietary patterns to obesity and related disorders such as non-alcoholic fatty liver disease (NAFLD) is limited in pediatric age. Aim of this study was to analyze the association between dietary patterns, obesity and development of severe steatosis and the metabolic syndrome in a series of children and adolescents referred for suspected NAFLD, and the interaction with the rs738409 I148M PNPLA3 polymorphism. Two hundred patients (112 females) had completed a food frequency and demographic questionnaire. Nearly 58 % were obese, and 32 % were overweight. Mild, moderate, and severe fatty liver was present in 60 (30 %), 87 (44 %), and 51 (26 %) participants, respectively. A great proportion of overweight/obese children and adolescents reported a correct dietary pattern. At multivariate ordinal regression analysis considering demographic, anthropometric, genetic, and behavioral determinants, the major determinant of steatosis severity was PNPLA3 I148M genotype (p < 0.0001), followed by older age (p = 0.017), higher waist circumference (p = 0.016), and less time spent practising physical exercise (p = 0.034). Furthermore, there was a significant interaction between PNPLA3 I148M and intake of sweetened beverages (p = 0.033) and of vegetables (p = 0.038). In conclusion, although dietary pattern was reportedly correct in at-risk overweight adolescents with NAFLD, we report a novel interaction between PNPLA3 I148M and dietary components with the severity of steatosis.     

Energy metabolism and protein balance in growing rats fed different levels of dietary fibre and protein

A study was performed to investigate the effect of different levels of dietary fibre (DF) and dietary protein on visceral organ size, digestibility, nitrogen balance and energy metabolism in rats. Thirty-six male Wistar rats, initial body weight about 76 g, were used in a factorial design consisting of three levels of DF (low, 100 g/kg DM; medium, 250 g/kg DM and high, 290 g/kg DM) and two levels of dietary protein (low, 120 g/kg DM and high, 223 g/kg DM). The added fibre source was soybean hulls and Danish fish meal was used as sole source of dietary protein. Measurements of gas-exchange were done on six rats (one group) while urine and faeces were collected individually. The ratio of food/empty body gain increased (P < 0.05) with increasing DF and decreasing levels of dietary protein. The weight of the digestive tract was larger (P < 0.05) in rats fed the high fibre diet than in those fed the low fibre diet. The digestibility of nutrients and energy decreased linearly with increasing level of soybean fibre (P < 0.05). An increased intake of DF was associated with a concomitant loss of protein and energy to faeces. The microbial degradation of NSP and other unabsorbed carbohydrates caused considerably changes in N metabolism of the colon. In rats fed the low protein diets increased levels of DF decreased N excretion in urine and increased N excretion in faeces, while the ratio of retained/digested protein remained constant. When rats were fed the high protein diet protein retention dropped in response to DF both absolute and relative to digested amount, indicating that energy intake could be a limiting factor. Heat production as a percentage of metabolizable energy (HP/ME) was higher (P < 0.05) in rats fed the low protein diet than in rats fed the high protein diet, but no significant difference was found among DF levels.     

Effect of light intensity on broiler behaviour and diurnal rhythms

Light intensity manipulation is an important management tool affecting broiler behaviour and physiology but still there is a debate regarding the optimum level to be used in confinement barns. Two experiments were completed to study the impact of light intensity (1, 10, 20 and 40 lx) on behaviour and diurnal rhythms of broilers raised to 35 d of age. For each experiment, 950 Ross × Ross 308 chicks were housed per room with replication of individual light intensity treatment in two environmentally controlled rooms. Within each large room, a small pen with 25 male and 25 female chicks was used for recording behaviour. Data were analyzed as a randomized complete block design with experiment acting as a block. All chicks were provided with 40 lx intensity and 23 h light until shifting to treatment light intensity and 17 h daylength at 7 d of age. For each replicate, behaviour was recorded for a 24 h period, starting at 16 or 17 d of age. At 23 d of age, three birds per room were bled at the start, middle and end of light and dark periods for melatonin estimation using RIA. When summarized over the 24 and 17 h observation periods, birds exposed to a light intensity of 1 lx rested more (P = 0.01) and preened (P < 0.05) and foraged (P < 0.05) less in comparison to other light intensities. Birds from all treatments exhibited diurnal rhythms for feeding, resting, drinking, walking, standing, foraging and preening behaviours with little or no activity during the 7 h dark phase. The serum melatonin levels at the start, middle and end of light and dark phases were unaffected by light intensity (P > 0.1). In conclusion, light intensity ranges from 1 to 40 lx did not affect melatonin levels or behavioural diurnal rhythms, but birds exposed to a light intensity of 1 lx rested more and preened less, potentially indicating a reduced welfare state.     

Effect of dietary fibre on nitrogen retention and fibre associated threonine losses in growing pigs

Apart from being an energy source, dietary fibre is also discussed to act as anti-nutritional factor reducing apparent precaecal protein and amino acid (AA) digestibility due to reduced absorption or increased endogenous secretion or both. However, the amounts of protein and AA of endogenous origin determined at the terminal ileum in cannulated animals do not represent the total losses associated with endogenous secretion. A high proportion of secreted protein is reabsorbed and does not reach the terminal ileum, and losses occur during synthesis of endogenous protein. Therefore, the present study used an alternative indirect approach, taking the reduction of nitrogen (N) retention in a threonine (Thr) limited diet as a sensitive indicator for fibre-associated Thr losses. Two experiments were conducted with 12 castrated male pigs each between 37 and 75 kg body weight to measure the effect of the intake of Thr and 150 and 300 g/d fibre from wheat bran (Exp. 1), or 150 g/d fibre from rape seed, cassava leaves, and cassava root peels, respectively (Exp. 2), on N retention. During two (Exp. 1) and three (Exp. 2) balance periods the animals were subjected to the dietary treatments according to a cross-over design. All animals received 1350 g/d of a wheat–soybean-based diet supplemented with free AA to ensure Thr being the first-limiting AA. To determine the effect of Thr on N retention, intake of the basal diet was reduced to 1150 g/d and supplemented with corn starch to reach equal energy intake and an unchanged AA pattern. With increasing BW additional starch was added to all diets to ensure a constant energy intake of 1.25 MJ ME/kg BW^0.75. Since the fibre sources contained small amounts of Thr, N retentions were corrected for precaecal digestible Thr intake originating from the fibre sources according to the Thr effect on N retention as determined in experiment 1. Corrected N retentions were affected by fibre level (p = 0.007) and source (p < 0.001). Fibre-associated Thr losses amounted to 3.3, 3.2, 1.2, and 1.1 g/kg fibre from wheat bran, rapeseed, cassava leaf, and cassava root peel, respectively. It is concluded that Thr losses per gram of dietary fibre depend on the fibre source and that fibre concentration and source in pig diets should be considered as a factor affecting Thr requirement.     

Effect of dietary fibre on nitrogen retention and fibre associated threonine losses in growing pigs

Apart from being an energy source, dietary fibre is also discussed to act as anti-nutritional factor reducing apparent precaecal protein and amino acid (AA) digestibility due to reduced absorption or increased endogenous secretion or both. However, the amounts of protein and AA of endogenous origin determined at the terminal ileum in cannulated animals do not represent the total losses associated with endogenous secretion. A high proportion of secreted protein is reabsorbed and does not reach the terminal ileum, and losses occur during synthesis of endogenous protein. Therefore, the present study used an alternative indirect approach, taking the reduction of nitrogen (N) retention in a threonine (Thr) limited diet as a sensitive indicator for fibre-associated Thr losses. Two experiments were conducted with 12 castrated male pigs each between 37 and 75 kg body weight to measure the effect of the intake of Thr and 150 and 300 g/d fibre from wheat bran (Exp. 1), or 150 g/d fibre from rape seed, cassava leaves, and cassava root peels, respectively (Exp. 2), on N retention. During two (Exp. 1) and three (Exp. 2) balance periods the animals were subjected to the dietary treatments according to a cross-over design. All animals received 1350 g/d of a wheat-soybean-based diet supplemented with free AA to ensure Thr being the first-limiting AA. To determine the effect of Thr on N retention, intake of the basal diet was reduced to 1150 g/d and supplemented with corn starch to reach equal energy intake and an unchanged AA pattern. With increasing BW additional starch was added to all diets to ensure a constant energy intake of 1.25 MJ ME/kg BW(0.75). Since the fibre sources contained small amounts of Thr, N retentions were corrected for precaecal digestible Thr intake originating from the fibre sources according to the Thr effect on N retention as determined in experiment 1. Corrected N retentions were affected by fibre level (p = 0.007) and source (p < 0.001). Fibre-associated Thr losses amounted to 3.3, 3.2, 1.2, and 1.1 g/kg fibre from wheat bran, rapeseed, cassava leaf, and cassava root peel, respectively. It is concluded that Thr losses per gram of dietary fibre depend on the fibre source and that fibre concentration and source in pig diets should be considered as a factor affecting Thr requirement.     

Effect of air temperature and humidity on ingestive behaviour of sheep

Thirty-two Polwarth ewes, of ages up to 1 year, were observed in a climatic chamber (24 to 45° C) for eight periods of 5 h each. The observations were made through a window in the chamber wall. All animals were observed four times, then shorn and observed four times again. The animals were given weighed quantities of water and feed consisting of commercial concentrate plus Rhodes grass (Chloris gayana) hay. The water and feed remaining after 5 h of observation were weighed. The following traits were analysed: time eating hay (TEH), time eating concentrate (TEC), time drinking water (TDW), weight of hay eaten (WHE), weight of concentrate eaten (WCE), volume of ingested water (VIW), ruminating time standing up (RTS), ruminating time lying down (RTL), idling time standing up (ITS), and idling time lying down (ITL). Shearing had a significant effect for all traits except ITS. Shearing resulted in higher values for all traits except for ITS and ITL. Ingestion of hay (TEH and WHE) decreased with increased air temperature and humidity, while the ingestion of concentrate (TEC) and WHE) and water (TDW and VIW) increased. Rumination decreased with increased air temperature and humidity, and was higher in shorn than in unshorn sheep.     

Fatigue during sustained maximal voluntary contraction of different muscles in humans: dependence on fibre type and body posture

Nine healthy men, aged between 25 and 35 years, performed sustained maximal voluntary contractions (MVC) of foot plantar, foot dorsal, and finger flexor muscles. Contractions lasted 10 min and were followed by short test contractions at 30% MVC during recovery. Two positions of the working extremity high or low were established by different body postures (supine or sitting). Under these conditions, studies of force, integrated electromyogram (iEMG), blood pressure, and heart rate showed firstly that force decreased throughout the first few minutes of maximal contraction but reached a near steady-state value after 5 to 6 min. Secondly, force decay and steady-state level depended on muscle group and body position. When sitting (low leg), muscles with a high incidence of slow twitch fibres (plantar flexors) showed a slower force decay and a higher relative steady-state force than fast dorsal flexor muscles. When supine (high leg), plantar and dorsal flexor muscles reached about the same low level of relative steady-state force. Changes in iEMG, blood pressure, and heart rate did not differ in the two positions. Thirdly, during recovery, plantar flexor muscles showed higher iEMG values as well as higher values of blood pressure and heart rate when supine than when sitting. Recovery of dorsal flexor muscles was little affected by body posture. Fourthly, force development and recovery of predominantly fast finger flexor muscles were almost independent of arm position. It was concluded that muscle fibre composition was the main factor in determining endurance capacity. However, endurance was influenced by changes in the hydrostatic blood pressure component.(ABSTRACT TRUNCATED AT 250 WORDS)     

Selected Gelling Agents in Canned Dog Food Affect Nutrient Digestibilities and Fecal Characteristics of Ileal Cannulated Dogs

Little is known about the effects of gelling agents in canned dog food on nutrient digestibilities and fecal characteristics. Dogs were fed canned diets with either no gelling agent (control) or one of three gelling agents, wheat starch, a guar gum/carrageenan mixture (50:50), and a locust bean meal (LBM)/ carrageenan mixture (50:50) incorporated at two levels (0.2 and 0.5% of the diet on a wet weight basis). Six dogs were fed each diet in a 6 ‐ 7 Youden square design. Dogs fed diets containing gelling agents had higher ileal digestibilities of OM (P = 0.05), fat (P < 0.01), GE (P = 0.02), and total amino acids (P = 0.04) and lower (P < 0.01) total tract DM digestibilities when compared to dogs fed the control diet. Fecal output by dogs fed the control diet, expressed on both an as-is (73.4g/d) and DM (45.6g/d) basis, was lower (P < 0.01) than for dogs fed gelling agent-containing diets (mean 102.3g/d as-is and 57.6g/d DM). Dogs fed the control diet also had lower ( P < 0.01) fecal DM percentages and higher (P = 0.02) fecal scores than dogs fed gelling agent-containing diets.     

Effect of individual or paired housing during post-weaning on feed intake, growth rate and behaviour of lambs

The aim of this study was to compare the behaviour and weight gain of weaned lambs penned either in pairs or alone, with visual and tactile contacts between pens. A 2 × 2 factorial experiment was conducted over seven weeks. Forty-eight Dorset lambs (twenty-five females and twenty-three males) were randomly distributed among pens. All pairs were non-twin lambs of the same sex. They were fed haylage (48.9% of DM) and a commercial pelleted feed both provided ad libitum. Weight of lambs was recorded at d0 and then weekly until d49. Consumption of dry matter and average daily gain (ADG) were also recorded. Lamb postures, activities and total bleats were directly observed in the morning and in the afternoon on six different days (d1, d2, d5, d12, d19, d26). On d1, observations were done only in the afternoon. For paired lambs, data were averaged by pen. Lambs penned alone were less active, slept more (P < 0.03) and walked less (P < 0.001) than paired lambs. Total bleats were not affected by housing treatment or sex, but were significantly higher for the first two days (P < 0.0001). Lamb growth performance was unaffected by the type of housing (P > 0.05). There was a significant difference in ADG (P < 0.001), total gain (P < 0.001), kg concentrate kg⁻¹ gain (P < 0.05) and final body weight (P < 0.05) in favor of males as compared to females. Our results suggest that a housing system in which individually raised lambs are allowed visual, tactile, and auditive contact with each other, compared to lambs housed in pairs, does not impact negatively on their growth and behaviour.     

Effect of glycerol on behaviour of amylose and amylopectin films

The effect of water and glycerol on sorption and calorimetric T_gs of amylose and amylopectin films were examined. The mechanical properties of the films were also analysed under varying glycerol content at constant RH and temperature. Based on changes observed in sorption and tensile failure behaviour glycerol was strongly interacted with both starch polymers. Even though water was observed to be more efficient plasticiser than glycerol, glycerol also affected the T_g. But in spite of the observed decrease in T_g under low glycerol contents brittleness of the films increased based on changes in elongation. The increase in brittleness of both polymers was also in agreement with their actual behaviour. At around 20% glycerol great change in the rheological properties occurred. Above 20% glycerol amylose film showed much larger elongation than the low glycerol content films and was still strong but the amylopectin produced a very week and non-flexible film.