Early transcriptional response in the jejunum of germ-free piglets after oral infection with virulent rotavirus

Germ-free piglets were orally infected with virulent rotavirus to collect jejunal mucosal scrapings at 12 and 18 hours post infection (two piglets per time point). IFN-gamma mRNA expression was stimulated in the mucosa of all four infected piglets, indicating that they all responded to the rotavirus infection. RNA pools prepared from two infected piglets were used to compare whole mucosal gene expression at 12 and 18 hpi to expression in uninfected germ-free piglets (n = 3) using a porcine intestinal cDNA microarray. Microarray analysis identified 13 down-regulated and 17 up-regulated genes. Northern blot analysis of a selected group of genes confirmed the data of the microarray. Genes were functionally clustered in interferon-regulated genes, proliferation/differentiation genes, apoptosis genes, cytoskeleton genes, signal transduction genes, and enterocyte digestive, absorptive, and transport genes. Down-regulation of the transport gene cluster reflected in part the loss of rotavirus-infected enterocytes from the villous tips. Data mining suggested that several genes were regulated in lower- or mid-villus immature enterocytes and goblet cells, probably to support repair of the damaged epithelial cell layer at the villous tips. Furthermore, up-regulation was observed for IFN-γ induced guanylate binding protein 2, a protein that effectively inhibited VSV and EMCV replication in vitro (Arch Virol 150:1213–1220, 2005). This protein may play a role in the small intestine’s innate defense against enteric viruses like rotavirus

Effect of Dietary Zinc Oxide on Morphological Characteristics, Mucin Composition and Gene Expression in the Colon of Weaned Piglets

The trace element zinc is often used in the diet of weaned piglets, as high doses have resulted in positive effects on intestinal health. However, the majority of previous studies evaluated zinc supplementations for a short period only and focused on the small intestine. The hypothesis of the present study was that low, medium and high levels of dietary zinc (57, 164 and 2,425 mg Zn/kg from zinc oxide) would affect colonic morphology and innate host defense mechanisms across 4 weeks post-weaning. Histological examinations were conducted regarding the colonic morphology and neutral, acidic, sialylated and sulphated mucins. The mRNA expression levels of mucin (MUC) 1, 2, 13, 20, toll-like receptor (TLR) 2, 4, interleukin (IL)-1β, 8, 10, interferon-γ (IFN-γ) and transforming growth factor-β (TGF-β) were also measured. The colonic crypt area increased in an age-depending manner, and the greatest area was found with medium concentration of dietary zinc. With the high concentration of dietary zinc, the number of goblet cells containing mixed neutral-acidic mucins and total mucins increased. Sialomucin containing goblet cells increased age-dependently. The expression of MUC2 increased with age and reached the highest level at 47 days of age. The expression levels of TLR2 and 4 decreased with age. The mRNA expression of TLR4 and the pro-inflammatory cytokine IL-8 were down-regulated with high dietary zinc treatment, while piglets fed with medium dietary zinc had the highest expression. It is concluded that dietary zinc level had a clear impact on colonic morphology, mucin profiles and immunological traits in piglets after weaning. Those changes might support local defense mechanisms and affect colonic physiology and contribute to the reported reduction of post-weaning diarrhea

High tannin sorghum in diets of japanese quails (Coturnix coturnix japonica)

This experiment was carried out to evaluate the effects of replacing corn by high tannin sorghum in diets of japanese quails (Coturnix coturnix japonica) on performance and egg quality. Two hundred and fifty-two quails with 50 weeks of age were evaluated during four periods of 21 days. The treatments consisted of diets containing 20, 40, 60, 80 and 100% of sorghum, and a control treatment (100% of corn). Diets were formulated so that the levels of energy, protein, amino acids (methionine+cystine and lysine), calcium and phosphorus were similar A completely randomized experimental design was used, with six treatments, six replicates and seven quails for experimental unit. Evaluated parameters were egg production (%), feed intake, feed: gain ratio (kg/kg and kg/dozen), egg mass (g), egg weight and egg quality (Haugh unit, eggshell percentage, shell thickness and yolk color). The increasing sorghum levels had a negative linear effect (p<0.05) on egg production (Y=82.9138 - 0.0966553X; R²=0.87), egg mass (Y= 8.0840626 - 0.009336932X; R²=0.80) and yolk color (Y=7.14340-0.0546875X; R²=0.98). On the other hand, the replacement had a positive linear effect on feed:gain ratio expressed as kg/kg (Y=0.372174 + 0.000536191X; R²=0.92) and as kg/dozen (Y=2.71516 + 0.00423485X; R²=0.94). Control treatment means were different by Dunnett's test (p<0.05) for egg mass (g) when compared to the treatment with 100% of replacement and for yolk color when compared to treatments containing 20, 40, 60, 80 and 100% of sorghum. There were no differences (p>0.05) in feed intake, egg weight, Haugh unit, eggshell percentage and shell thickness. In conclusion, up to 80% of high tannin sorghum may be used on diets if xanthophyll pigments are added in order to maintain the commercial quality of final products