High occurrence of carbapenem-resistant Escherichia coli isolates from healthy rabbits (Oryctolagus cuniculus): first report of blaIMI and blaVIM type genes from livestock in Tunisia.

We aimed to study the antibiotic susceptibility and possible occurrence of extended-spectrum beta-lactamases (ESBL)/carbapenemase-producing Escherichia coli isolates collected from rabbits in Tunisia. In all, 35 faecal samples from healthy rabbits were collected from one farm and E. coli were isolated from three media: antibiotic-free TBX agar, TBX+2 mg l-1 cefotaxime and TBX+1 mg l-1 imipenem. In total, 39 E. coli isolates were recovered; the majority showed resistance to at least one antibiotic and none was ESBL producer. Carbapenem resistance was detected in 16 isolates from either selective or un-selective media. Phenotypic methods used to detect carbapenemase production showed two positive isolates by Modified Hodge Test, six metallo-carbapenemase producers (Imipenem disc+EDTA) and all were temocillin resistant (possible OXA-48 carbapenemase). blaVIM and blaIMP type genes were detected in two and one isolates, respectively; one of them harboured both genes. Isolates contained common genes encoding resistance to sulphonamides (sul1, sul2), tetracycline (tetA, tetB, tetC) and fluoroquinolones (qnrS, aac(6')-Ib-cr). Class 1 and 2 integrons were detected in five and four isolates, respectively. These findings highlight the importance of rabbit production as reservoir of carbapenem-resistant E. coli and argument the first report of blaVIM and blaIMP genes in livestock in Tunisia.

Characterization of bacteriocinogenic Enterococcus isolates from wild and laboratory rabbits for the selection of autochthonous probiotic strains in Tunisia.

AIM: The objective of this study was to characterize lactic acid bacteria (LAB) from rabbits to be used as potential autochthonous probiotic. METHODS AND RESULTS: Fifteen faecal samples were collected from wild and laboratory rabbits. One hundred and eight isolates were collected and tested for their inhibitory power against eight pathogenic bacteria. Among them, 43 Enterococcus isolates were able to inhibit at least one pathogen. Enterocine genes entA, entB and entP were detected in 14, 17 and 22 isolates, respectively. These isolates were tested for their antibiotic susceptibility and genes encoding virulence factors. Relevant phenotypes of antibiotic resistance were observed especially for ampicillin, vancomycin and linezolid. The following virulence genes were detected (number of positive isolates): hyl (5), esp (8), gelE (30), agg (2), ace (21), efa (6), CylLL/s (5), cob (26), cpd (32) and ccf (33). Five isolates were considered as safe and showed tolerance to both acid and bile salt. CONCLUSION: Bacteriocinogenic enterococci isolates from rabbits may show relevant resistance phenotypes and virulence factors. In addition, one Enterococcus durans isolate presents promising autochthonous probiotic candidate. SIGNIFICANCE AND IMPACT OF THE STUDY: This study reveals interesting properties for E. durans isolate and supports their utilization as autochthonous probiotic in rabbit husbandry.

Heat stress effects on livestock: molecular, cellular and metabolic aspects, a review.

Elevated ambient temperatures affect animal production and welfare. Animal's reduced production performances during heat stress were traditionally thought to result from the decreased feed intake. However, it has recently been shown that heat stress disturbs the steady state concentrations of free radicals, resulting in both cellular and mitochondrial oxidative damage. Indeed, heat stress reorganizes the use of the body resources including fat, protein and energy. Heat stress reduces the metabolic rates and alters post-absorptive metabolism, regardless of the decreased feed intake. Consequently, growth, production, reproduction and health are not priorities any more in the metabolism of heat-stressed animals. The drastic effects of heat stress depend on its duration and severity. This review clearly describes about biochemical, cellular and metabolic changes that occur during thermal stress in farm animals.

Effects of oil and natural or synthetic vitamin E on ruminal and milk fatty acid profiles in cows receiving a high-starch diet.

Among trans fatty acids, trans-10,cis-12 CLA has negative effects on cow milk fat production and can affect human health. In high-yielding dairy cows, a shift from the trans-11 to the trans-10 pathway of biohydrogenation (BH) can occur in the rumen of cows receiving high-concentrate diets, especially when the diet is supplemented with unsaturated fat sources. In some but not all experiments, vitamin E has been shown to control this shift. To ascertain the effects of vitamin E on this shift of BH pathway, 2 studies were conducted. The first study explored in vitro the effects of addition of natural (RRR-α-tocopherol acetate) and synthetic (dl-α-tocopherol acetate) vitamin E. Compared with control and synthetic vitamin E, the natural form resulted in a greater trans-10/trans-11 ratio; however, the effect was very low, suggesting that vitamin E was neither a limiting factor for rumen BH nor a modulator of the BH pathway. An in vivo study investigated the effect of natural vitamin E (RRR-α-tocopherol) on this shift and subsequent milk fat depression. Six rumen-fistulated lactating Holstein cows were assigned to a 2×2 crossover design. Cows received 20-kg DM of a control diet based on corn silage with 22% of wheat, and after 2 wk of adaptation, the diet was supplemented with 600 g of sunflower oil for 2 more weeks. During the last week of this 4-wk experimental period, cows were divided into 2 groups: an unsupplemented control group and a group receiving 11 g of RRR-α-tocopherol acetate per day. A trans-10 shift of ruminal BH associated with milk fat depression due to oil supplementation of a high-wheat diet was observed, but vitamin E supplementation of dairy cows did not result in a reversal toward a trans-11 BH pathway, and did not restore milk fat content.

Interleukin 10 promoter region polymorphisms in inflammatory bowel disease in Tunisian population.

OBJECTIVE: To test whether IL-10 promoter region polymorphisms are associated with susceptibility to inflammatory bowel disease, we examined the contribution of interleukin- 10 (IL-10) gene polymorphisms to Crohn's disease (CD) and Ulcerative colitis disease (UC) occurrence and also to CD phenotype. MATERIELS AND METHODS: SNPs at positions -627 (C > A) and -1117 (G > A) in the IL-10 promoter were determined in a sample of 105 Tunisian patients with IBD (75 CD and 30 UC) and 90 matched healthy controls. RESULTS: The 627 CA genotype is associated with ileal location (p = 0.015) and with stricturing (p = 510-3) and penetrating (p = 310-3) presentation of CD. An additive effect between IL10 variants and CARD15 3020 insC mutation (p = 0,006) on severe forms of CD was shown. CONCLUSIONS: In Tunisian population, the 3020insC insertion in NOD2/CARD15 gene is a marker of susceptibility to CD, while the A allele at position -627 in the IL-10 promoter increases the risk of CD ileal location and severe disease presentation. A genetic epistasis between IL-10 gene polymorphisms and CARD15/NOD2 gene mutation was suggested.

3020insC insertion in NOD2/CARD15 gene, a prevalent variant associated with anti-Saccharomyces cerevisiae antibodies and ileal location of Crohn's disease in Tunisian population.

OBJECTIVE: Our aim is to investigate the relation between CARD15 3020insC mutation, anti-Saccharomyces cerevisiae antibodies (ASCA) and disease phenotype, in Tunisian inflammatory bowel disease (IBD) patients. MATERIALS: A hundred Tunisian patients with IBD (75 Crohn's disease CD and 25 ulcerative colitis UC) and 60 matched healthy controls were studied. METHODS: CARD15 mutation was analysed by using an allele-specific polymerase chain reaction and sequencing. Assessment of ASCA in serum was performed by ELISA. RESULTS: The frequency of the mutation was significantly higher in Crohn's disease than in control (p = 0,0005; OR = 20.45; CI 95% = 2.86-413.85) and did not differ statistically in UC group (p = 0, 05) from control. ASCAs were present in 60% of CD and 20, 8% of UC. CONCLUSION: This study suggests that in northern Tunisian population, 3020insC mutation in NOD2/CARD15 gene is a prevalent mutation leading to the typical Crohn's disease including ileal location, stricturing and penetrating clinical types and ASCA expression.

Hypoglycemic effect of oral insulin in diabetic rabbits using pH-dependent coated capsules containing sodium salicylate without and with sodium cholate.

The hypoglycemic effect of oral insulin (20 U and 40 U) capsules coated with a pH-dependent soluble polymer (Eudragit S100) and containing sodium salicylate (50 mg) without and with sodium cholate (50 mg) was studied in alloxan-hyperglycemic rabbits and compared with that of s.c. insulin injection (20 U). The capsules containing 20 U insulin + sodium salicylate (50 mg) produced a significant reduction in plasma glucose level to 82 and 73% of initial values at 2 and 3 hr after administration, respectively. The blood glucose level slowly returned to normal values at 5 hr. The AUC0-5 hr was 73.7 +/- 43.5 mg.hr/dl compared to 242 +/- 70.5 mg.hr/dl for insulin (20 U, s.c.) with a relative hypoglycemia of 30.4%. A higher dose of oral insulin (40 U) + sodium salicylate (50 mg) was more effective in reducing plasma glucose level which steadily decreased and reached 56% of the initial value by 5 hr (AUC0-5 hr = 132 +/- 41.5 mg.hr/dl and relative hypoglycemia = 27.3%). Sodium cholate (50 mg), however, slightly improved sodium salicylate effect producing an AUC0-5 hr of 139 +/- 37.3 mg.hr/dl with relative hypoglycemia of 28.7%. The relative hypoglycemia of pH-dependent coated capsules reached in the present experiment is the highest found so far.

[Comparison of different adjustment models of curves of fecal excretion of transit markers]. / Comparaison de différents modèles d'ajustement des courbes d'excrétion fécale des marqueurs du transit.

Seventy nine fecal excretion curves of rare earth were adjusted with 3 published models (Grovum and Williams, 1973; Dhanoa et al, 1985; Siddons et al, 1983). The models provided statistically similar estimations of particulate turnover in the first compartment and mean retention time. However, some important individual differences between parameter values could be observed from one model to another.

[Influence of the quantity of ingested dry matter and food retention time on feed digestibility in dairy goats]. / Influence de la quantité de matière sèche ingérée et du temps de séjour des aliments sur la digestibilité de la ration par la chèvre laitière.

Simultaneous measurements of organic matter digestibility (OMD) and particulate mean retention time (MRT) of diets containing various proportions of hay and concentrate (bran or beet pulp) were performed in lactating or dry goats. Beyond the hay and concentrate influences, the OMD decreased by 0.5 and 1.3 points as the dry matter intake level increased by 10 g/kg LW0.75 and MRT decreased by 5 h, respectively.