Performance, digestive disorders and the intestinal microbiota in weaning rabbits are affected by a herbal feed additive

[EN] A herbal feed additive (Digestarom(R), containing a mixture of onion, garlic, caraway, fennel, gentian, melissa, peppermint, anise, oak bark and clove) was fed to rabbit does and kits to study its impact on performance, post-weaning digestive disorders and intestinal microbiota. Two groups of 9 doe rabbits and their offspring, after weaning, were fed a standard diet without or with the addition of 300 mg Digestarom(R)/kg diet. Forty kits from each group were weaned at 28 d of age weighing 0.614±0.005 kg. They were caged in groups of four rabbits (10 cages/treatment) and fed the same diet as their mothers for 13 d. Weight gain and feed intake of the kits fed Digestarom(R) was 18 and 14% higher, respectively, than those fed control diet (P<0.001), with no differences in the feed conversion. Rabbits were killed 13 d after weaning and 10 healthy animals from the Digestarom(R) group and 10 healthy and 10 diseased animals from the control group were dissected. Healthy rabbits fed control diet and those fed Digestarom(R) showed closer intestinal digesta dry matter, pH and volatile fatty acid (VFA) profi les, compared to diseased animals. VFA concentration in the small intestine was higher (P=0.030) in the diseased animals of the control group compared with the healthy and Digestarom(R) fed rabbits. However, no differences were observed in VFA concentration in stomach or caecum contents. The fermentation profi le of diseased animals was characterised by a higher proportion of propionic, i- and n-valeric acids in the caecal contents (P<0.001), and an increased i-butyric acid concentration in the stomach and caecum contents (P=0.014), whereas n-butyric acid was reduced (P<0.033) compared with the healthy or Digestarom(R) fed rabbits. Denaturing gradient gel electrophoresis indicated a higher caecal bacterial diversity in the control rabbits compared with kits fed Digestarom(R) (P=0.008). The reduced evenness factor (P<0.010) also indicated that the bacterial composition included more dominant species in the Digestarom(R) group. Under our experimental conditions, the tested herbal feed additive Digestarom(R) had protective effects in rabbit kits after weaning, making it an interesting alternative for establishing nutritional strategies.Krieg, R.; Vahjen, W.; Awad, W.; Sysel, M.; Kroeger, S.; Zocher, E.; Hulan, H.... (2009). Performance, digestive disorders and the intestinal microbiota in weaning rabbits are affected by a herbal feed additive. World Rabbit Science. 17(2):87-95. doi:10.4995/wrs.2009.662879517

Agent-Based Model of Therapeutic Adipose-Derived Stromal Cell Trafficking during Ischemia Predicts Ability To Roll on P-Selectin

Intravenous delivery of human adipose-derived stromal cells (hASCs) is a promising option for the treatment of ischemia. After delivery, hASCs that reside and persist in the injured extravascular space have been shown to aid recovery of tissue perfusion and function, although low rates of incorporation currently limit the safety and efficacy of these therapies. We submit that a better understanding of the trafficking of therapeutic hASCs through the microcirculation is needed to address this and that selective control over their homing (organ- and injury-specific) may be possible by targeting bottlenecks in the homing process. This process, however, is incredibly complex, which merited the use of computational techniques to speed the rate of discovery. We developed a multicell agent-based model (ABM) of hASC trafficking during acute skeletal muscle ischemia, based on over 150 literature-based rules instituted in Netlogo and MatLab software programs. In silico, trafficking phenomena within cell populations emerged as a result of the dynamic interactions between adhesion molecule expression, chemokine secretion, integrin affinity states, hemodynamics and microvascular network architectures. As verification, the model reasonably reproduced key aspects of ischemia and trafficking behavior including increases in wall shear stress, upregulation of key cellular adhesion molecules expressed on injured endothelium, increased secretion of inflammatory chemokines and cytokines, quantified levels of monocyte extravasation in selectin knockouts, and circulating monocyte rolling distances. Successful ABM verification prompted us to conduct a series of systematic knockouts in silico aimed at identifying the most critical parameters mediating hASC trafficking. Simulations predicted the necessity of an unknown selectin-binding molecule to achieve hASC extravasation, in addition to any rolling behavior mediated by hASC surface expression of CD15s, CD34, CD62e, CD62p, or CD65. In vitro experiments confirmed this prediction; a subpopulation of hASCs slowly rolled on immobilized P-selectin at speeds as low as 2 µm/s. Thus, our work led to a fundamentally new understanding of hASC biology, which may have important therapeutic implications

Positional analysis of egg triacylglycerols and phospholipids from hens fed diets enriched in refined seal blubber oil

The effect of feeding laying hens with refined seal blubber oil (SBO, containing 22.2% ω3 polyunsaturated fatty acids) on the fatty acids composition and regiospecific distribution of fatty acids in triacylglycerols (TAG) and phospholipids (PL) of egg produced was investigated. The hens were fed four diets containing 0 (control), 1.25, 2.5 or 5% SBO for 5 and 9 weeks. Comparison of the total fatty acids composition indicated that a 5 week feeding period was sufficient to obtain the highest amount of total polyunsaturated fatty acids in the eggs. The fatty acids composition of the egg lipids reflected the fatty acids composition of the diet. The substantial reduction in the ω6/ω3 ratio (ie 8.5 to 2.6) is of interest, and is in line with the recommendations of health authorities in several countries, where it has been suggested that the human diet should contain a ω6/ω3 ratio of 3–4. The greatest reduction of the ω6/ω3 ratio occurred for diet A (control) and diet B (1.25% SBO). Principal component analysis analysis of the fatty acids composition of egg lipid showed four clusters representing: (i) the control diet; (ii) the diet containing 1.25% SBO as well as samples obtained from feeding 2.5% SBO for 9 weeks; (iii) the diet with 5% SBO; and (iv) samples obtained from hens fed 2.5% SBO for 5 weeks. More ω-3 polyunsaturated fatty acids (ω3 PUFA) were incorporated in phosphatidylethanolamine and phosphatidylcholine than in TAG. Although ω3 were predominantly linked in the position Sn-1,3 of TAG in SBO, they were esterified in the Sn-2 position of the TAG and PL of eggs obtained after feeding laying hens with enriched diets