Intestinal barrier function and absorption in pigs after waeaning: a review

Under commercial conditions, weaning of piglets is associated with social, environmental and dietary stress. Consequently, small-intestinal barrier and absorptive functions deteriorate within a short time after weaning. Most studies that have assessed small-intestinal permeability in pigs after weaning used either Ussing chambers or orally administered marker probes. Paracellular barrier function and active absorption decrease when pigs are weaned at 3 weeks of age or earlier. However, when weaned at 4 weeks of age or later, the barrier function is less affected, and active absorption is not affected or is increased. Weaning stress is a critical factor in relation to the compromised paracellular barrier function after weaning. Adequate feed intake levels after weaning prevent the loss of the intestinal barrier function. Transcellular transport of macromolecules and passive transcellular absorption decrease after weaning. This may reflect a natural intestinal maturation process that is enhanced by the weaning process and prevents the pig from an antigen overload. It seems that passive and active absorption after weaning adapt accurately to the new environment when pigs are weaned after 3 weeks of age. However, when weaned at 3 weeks of age or earlier, the decrease in active absorption indicates that pigs are unable to sufficiently adapt to the new environment. To improve weaning strategies, future studies should distinguish whether the effect of feed intake on barrier function can be directed to a lack of a specific nutrient, i.e. energy or protein

Estimating the cumulative effects of the nature-based tourism in a coastal dolphin population from southern Kenya

Due to the growth of nature-based tourism worldwide, behavioural studies are needed to assess the impact of this industry on wildlife populations and understand their short-term effect. Tourism impact on dolphin populations remain poorly documented in developing countries. This study investigates the effects of nature-based tourism on the behaviour of the Indo-Pacific bottlenose dolphins (Tursiops aduncus) in southern Kenya. We used Markov chain models to estimate transition probabilities between behavioural states in the presence and absence of tourist boats, and assess the overall behavioural budgets. Based on these data and the tourism intensity in the area, we quantified the potential tourist boat disturbance over the period 2006-2013. Our results demonstrated that tourist boat interactions affected dolphins' behavioural budgets, with a significant decrease in the overall amount of time travelling and an increase in diving. The average duration of travelling and resting decreased significantly in the presence of boats. Although the cumulative tourism exposure was not significant for the dolphin population at their current levels, these impacts should be taken into consideration with the potential tourism growth in the area. This is particularly important if tourism reaches periods of high intensity, as we have shown that these periods could have a significant impact for the species, particularly where home-range and core areas are highly overlap by this activity. Understanding the effect of human disturbance variations from previous years may help to predict the consequences on dolphin populations, towards achieving a more ecological and economic sustainability of the activity

Evaluation of vegetable protein in canine diets: assessment of performance and apparent ileal amino acid digestibility using a broiler model

Recent technological advances in the human food industry with respect to meat processing have decreased the availability of animal proteins to the pet food industry which typically formulates diets with an excess of animal protein. In the long term, this is not sustainable; thus, alternative protein sources need to be investigated. This study examined three canine diets, comparing a typical animal protein-based diet (control) with two experimental diets where the animal protein was substituted in part with vegetable protein (formulated based either on total protein or amino acid content) using a broiler model. Each diet was fed to six cages each containing two birds from day 15, 18 cages in total (36 birds). Excreta were collected from days 19 to 21. On day 23, birds were euthanized and weighed, and their ileal digesta were collected and pooled for each cage. In addition, one leg per cage was collected for evaluation of muscle mass. Results showed no significant difference in animal performance (feed intake or live weight gain) or muscle to leg proportion across the diets. Birds fed the control diet and the diet balanced for amino acid content exhibited the greatest coefficients of apparent metabolizability for nitrogen (p < .001). Birds fed the diets that contained partial replacement of animal with vegetable protein generally had greater ileal digestibility of amino acids compared to birds fed the control (animal protein) diet. Analysis of excreta showed no dietary difference in terms of dry matter content; however, birds fed the diet balanced for total protein and the diet balanced for amino acid content had significantly greater excreta nitrogen than the control (p = .038). Overall, the study suggests vegetable proteins when formulated based on amino acid content are a viable alternative to animal proteins in canine diets

Effectiveness of head starting to bolster Philippine crocodile Crocodylus mindorensis.

Conservation Biology - ol

Maternal Antibiotic-Induced Early Changes in Microbial Colonization Selectively Modulate Colonic Permeability and Inducible Heat Shock Proteins, and Digesta Concentrations of Alkaline Phosphatase and TLR-Stimulants in Swine Offspring

Elevated intake of high energy diets is a risk factor for the development of metabolic diseases and obesity. High fat diets cause alterations in colonic microbiota composition and increase gut permeability to bacterial lipopolysaccharide, and subsequent low-grade chronic inflammation in mice. Chronic inflammatory bowel diseases are increasing worldwide and may involve alterations in microbiota-host dialog. Metabolic disorders appearing in later life are also suspected to reflect changes in early programming. However, how the latter affects the colon remains poorly studied. Here, we hypothesized that various components of colonic physiology, including permeability, ion exchange and protective inducible heat shock proteins (HSP) are influenced in the short- and long-terms by early disturbances in microbial colonization. The hypothesis was tested in a swine model. Offspring were born to control mothers (n = 12) or mothers treated with the antibiotic (ATB) amoxicillin around parturition (n = 11). Offspring were slaughtered between 14 and 42 days of age to study short-term effects. For long-term effects, young adult offspring from the same litters consumed a normal or a palm oil-enriched diet for 4 weeks between 140 and 169 days of age. ATB treatment transiently modified maternal fecal microbiota although the minor differences observed for offspring colonic microbiota were nonsignificant. In the short-term, consistently higher HSP27 and HSP70 levels and transiently increased horseradish peroxidase permeability in ATB offspring colon were observed. Importantly, long-term consequences included reduced colonic horseradish peroxidase permeability, and increased colonic digesta alkaline phosphatase (AP) and TLR2- and TLR4-stimulant concentrations in rectal digesta in adult ATB offspring. Inducible HSP27 and HSP70 did not change. Interactions between early ATB treatment and later diet were noted for paracellular permeability and concentrations of colonic digesta AP. In conclusion, our data suggest that early ATB-induced changes in bacterial colonization modulate important aspects of colonic physiology in the short- and longterms

Nutrition driven small-intestinal development and performance of weaned pigs and young broilers

The relative importance of animal husbandry and nutrition during the first weeks after weaning in pigs and after hatch in broilers has increased considerably over the past 50 years as a result of the tremendous improvement in daily body weight (BW) gain. Substantial changes in weight, architecture, and physiology of the small intestine occur early in the life of these animals. The optimal function of the small intestines is fundamental for nutrient absorption from the diet and for health. Nutrient requirement studies conducted on these animals have largely overlooked the very young animal. It is therefore logical that there are still gaps in our knowledge of the nutrition of these animals during this particular stage of life. The objective of this thesis was to improve small-intestinal development and performance of pigs after weaning and young broilers by ways of an optimal nutrient composition of the diet. In experiments with broilers, it was shown that enhanced dietary ideal protein (IP) concentrations in the starter diet increased BW gain in the starter phase and in the subsequent grower phase. Moreover, the effects of enhanced IP concentrations in the starter diet on BW gain are more marked than the effects in the grower and finisher diets. However, BW gain hardly improved in response to dietary IP increment during the first 3 d after hatch, whereas in the consecutive 3 d, BW gain improved substantially with enhanced dietary IP concentrations. This suggests that the first 3 d after hatch, from a nutritional point of view, are substantially different from the next consecutive days in the life of broiler chicks. Moreover, a 30% increase in dietary IP increased the duodenum weight between 6 and 9 d of age. Thus, in young broilers, a greater relative small-intestinal weight is associated with a greater BW gain. However, this thesis did not make a clear determination of the functional changes of the small intestine after hatch in broilers. A review of the literature showed that after weaning in pigs, the barrier function of the tight junctions of the small intestine is disturbed, and transcellular barrier function seems to improve after weaning. In the first study with pigs, the data here showed that paracellular barrier functions, as measured with orally administered lactulose, did not correlate with bacterial translocation or transcellular barrier function, as measured with horseradish peroxidase in Ussing chambers. Therefore, it was concluded that lactulose recovery in the urine of pigs after weaning is not associated with risk factors for infection. The last study with pigs showed that dietary protein with dextrose stimulates mucosal weight after weaning. However, the combination of protein with dextrose had no substantial effect on small-intestinal barrier function, whereas dietary starch with dextrose improved small-intestinal barrier function. In conclusion, optimising protein nutrition in broilers after hatch has a great potential to further improve overall broiler performance. In particular, knowledge regarding optimal nutrition during the first 3 d after hatch is still lacking. Furthermore, dietary protein is a potent stimulator for growth of the proximal small intestine in broilers and of the small-intestinal mucosa in pigs. However, mucosal mass and luminal protein are of minor importance for small-intestinal barrier function in pigs after weaning. In contrast, the luminal carbohydrate supply or energy level is important for maintaining small-intestinal barrier function

Nutrition driven small-intestinal development and performance of weaned pigs and young broilers

<p> The relative importance of animal husbandry and nutrition during the first weeks after weaning in pigs and after hatch in broilers has increased considerably over the past 50 years as a result of the tremendous improvement in daily body weight (BW) gain. Substantial changes in weight, architecture, and physiology of the small intestine occur early in the life of these animals. The optimal function of the small intestines is fundamental for nutrient absorption from the diet and for health. Nutrient requirement studies conducted on these animals have largely overlooked the very young animal. It is therefore logical that there are still gaps in our knowledge of the nutrition of these animals during this particular stage of life. The objective of this thesis was to improve small-intestinal development and performance of pigs after weaning and young broilers by ways of an optimal nutrient composition of the diet. In experiments with broilers, it was shown that enhanced dietary ideal protein (IP) concentrations in the starter diet increased BW gain in the starter phase and in the subsequent grower phase. Moreover, the effects of enhanced IP concentrations in the starter diet on BW gain are more marked than the effects in the grower and finisher diets. However, BW gain hardly improved in response to dietary IP increment during the first 3 d after hatch, whereas in the consecutive 3 d, BW gain improved substantially with enhanced dietary IP concentrations. This suggests that the first 3 d after hatch, from a nutritional point of view, are substantially different from the next consecutive days in the life of broiler chicks. Moreover, a 30% increase in dietary IP increased the duodenum weight between 6 and 9 d of age. Thus, in young broilers, a greater relative small-intestinal weight is associated with a greater BW gain. However, this thesis did not make a clear determination of the functional changes of the small intestine after hatch in broilers. A review of the literature showed that after weaning in pigs, the barrier function of the tight junctions of the small intestine is disturbed, and transcellular barrier function seems to improve after weaning. In the first study with pigs, the data here showed that paracellular barrier functions, as measured with orally administered lactulose, did not correlate with bacterial translocation or transcellular barrier function, as measured with horseradish peroxidase in Ussing chambers. Therefore, it was concluded that lactulose recovery in the urine of pigs after weaning is not associated with risk factors for infection. The last study with pigs showed that dietary protein with dextrose stimulates mucosal weight after weaning. However, the combination of protein with dextrose had no substantial effect on small-intestinal barrier function, whereas dietary starch with dextrose improved small-intestinal barrier function. In conclusion, optimising protein nutrition in broilers after hatch has a great potential to further improve overall broiler performance. In particular, knowledge regarding optimal nutrition during the first 3 d after hatch is still lacking. Furthermore, dietary protein is a potent stimulator for growth of the proximal small intestine in broilers and of the small-intestinal mucosa in pigs. However, mucosal mass and luminal protein are of minor importance for small-intestinal barrier function in pigs after weaning. In contrast, the luminal carbohydrate supply or energy level is important for maintaining small-intestinal barrier function.</p