At weaning (33 days of age), 246 hybrid rabbits (782 6 53 g live weight) were divided into six experimental groups and fed ad libitum six iso-ADF diets formulated according to a bifactorial arrangement with two protein levels (152 and 162 g/kg) and three soluble fibre-to-starch ratios (0.2, 0.6 and 1.5), the latter obtained by replacing starch (from 209 to 91 g/kg) with soluble fibre (from 48 to 136 g/kg). The trial lasted for 42 days until slaughter. The rabbits that were fed the diet with the highest protein level and the lowest soluble fibre-to-starch ratio showed the highest mortality rate (17.1% v. 1.7% on average; P , 0.001) and sanitary risk (mortality 1 morbidity: 20.0% v. 8.1%; P 5 0.04) compared with the rabbits fed the other diets. With increasing dietary crude protein level, the digestibility of dry matter (DM; 0.615 to 0.626) and gross energy (0.620 to 0.630) as well as aNDF (without sodium sulphite; 0.298 to 0.323) and hemicelluloses (0.417 to 0.461) significantly (0.001 , P , 0.10) improved. Moreover, total volatile fatty acids (VFAs) in the caecal content increased (59.0 to 68.4 mmol/l; P 5 0.01) and ileum crypt depth tended to reduce (P 5 0.07). Neither growth performance nor slaughter results were affected by the protein level. When increasing soluble fibre-to-starch ratio, the digestibility of DM and gross energy did not change, whereas the digestibility of aNDF (0.264 to 0.352), ADF (0.167 to 0.267) and hemicelluloses (0.400 to 0.470) linearly increased (P , 0.001). At caecum, N-ammonia tended to decrease linearly (P 5 0.08), total VFA concentration (56.0 to 67.3 mmol/l) and acetate proportion (80.4 to 83.3 mmol/100 mmol VFA) linearly increased (P , 0.01), whereas butyrate and valerate proportions decreased (0.01 , P , 0.05). Growth performance was similar among groups, whereas at slaughter the proportion of the gastrointestinal tract linearly increased (177 to 184 g/kg; P , 0.01) without effect on dressing percentage, however. As soluble fibre-to-starch ratio increased, meat pH linearly decreased and lightness (L*), redness (a*) and yellowness (b*) colour indexes increased (0.01 , P , 0.05).

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From weaning (34 d of age) until slaughter (76 d), 216 hybrid rabbits were divided into six experimental groups and fed ad libitum six iso-protein (CP: 15.9% as-fed), iso-starch (9.1%) and iso-ADF (21.4%) diets formulated in a bi-factorial arrangement, with three soluble fi bre levels (LS: 5.8% vs. MS: 7.4% vs. HS: 8.5%) and two protein sources (Soy: soybean meal vs. Sun: sunfl ower meal). The increase in dietary soluble fi bre level linearly increased (P L <0.001) in vivo digestibility of dry matter (from 55.4 to 61.3%), gross energy and fi bre fractions (from 14.8 to 25.7% for acid detergent fi bre; from 40.3 to 49.2% for insoluble hemicelluloses; from 85.0 to 93.9% for soluble fi bre). Replacing soybean with sunfl ower meal tended to decrease crude protein digestibility (73.1 vs. 72.6%, P=0.058) and reduced acid detergent fi bre digestibility (22.0 vs. 18.4%, P<0.001), while improving ether extract digestibility (69.3 vs. 70.8, P<0.001). The nutritive values of the experimental diets increased with soluble fi bre level (digestible energy from 9.0 to 9.9 MJ/kg) regardless of the protein source. Intestinal mucosa traits at 56 d of age were not affected, while caecal pH linearly decreased (from 6.19 to 5.97; P L =0.017) with increasing dietary soluble fi bre. During the trial, health problems were moderate (mortality 3.4% and morbidity 15.6%) and not affected by feeding treatments. With increasing soluble fi bre level, rabbit daily weight gain and fi nal live weight linearly increased (P L =0.045) and feed conversion improved (from 3.55 to 3.30, P L <0.001). Protein source did not affect intestinal traits or growth performance. Slaughter results and meat quality were unaffected by feeding treatments.

To evaluate the effect of digestible fibre (DF, hemicelluloses+pectins)/ADF ratio (1.0 and 1.3) and starch level (12, 15, and 18%) on health status, digestive physiology, growth performance, and carcass traits, 246 rabbits weaned at 27 d were fed until slaughter (76 d) with six diets formulated according to a bifactorial arrangement (2 DF/ADF ratios by 3 starch levels). Increasing DF/ADF improved DM digestibility (P<0.01), but did not affect growth performance, caecal content characteristics and slaughter traits. Increasing starch level improved digestibility efficiency and conversion index (P<0.001), decreased ileal mucosa villi height (P=0.04), without affecting growth performance, caecal fermentation and slaughter results. The increase of DF/ADF ratio tended to reduce mortality (25.0 vs 17.6%; P=0.11), whereas the raise of starch greatly increased mortality (from 6.9 to 43.1%; P<0.001) and sanitary risk (from 13.9 to 63.9%; P<0.001)

To evaluate the effect of digestible fibre (DF) to starch ratio (0.8, 1.5, and 2.8) and protein level (15% and 16%) on health status, digestive physiology, growth performance, and carcass traits, 246 rabbits weaned at 33 d were fed until slaughter (75 d) six diets formulated according to a bi-factorial arrangement (3 DF to starch ratios by 2 protein levels). Growth performance and carcass quality at slaughter were not af- fected by treatments. Increasing DF to starch ratio did not modify dry matter digestibility (62.0% on average), while increased (P<0.001) DF digestibility (52.3 to 68.1%), stimulated caecal fermentation (total VFA: 56.0 vs 67.8 and 67.2 mmol/l; P=0.02) and changed VFA molar proportions. Increasing dietary protein increased digestibility of dry matter (P=0.02), crude protein (P<0.001) and digestible fibre (P<0.001) and increased cae- cal VFA production (P<0.01). The highest mortality (17.1% vs 1.5% average mortality of the other groups, P<0.001) was found in rabbits fed the diet with the lowest DF to starch ratio and the highest protein level

The chemical composition and the level of seven indicator congeners of PCB (BZ/IUPAC no. 28, 52, 101, 118, 138, 153, and 180) were determined in 133 specimens of farm-raised European sea bass (Dicentrarchus labrax). The fish were caught from different aquaculture rearing systems: extensive fish valley, semi-intensive ponds, sea-cages, and intensive concrete tanks. Fresh fillet chemical composition differed among the rearing systems (fat: 2.9, 7.5, 7.1, and 9.4%; P<0.001). Total concentrations of indicator congeners were below the EU limit (200ng/g fat) for meat, poultry and eggs, being the lowest in extensively-reared sea bass (75ng/g fat), intermediate in sea bass from semi-intensive ponds (119) and sea cages (116), and the highest in intensively-reared fish (133) (P<0.001). Similarly, PCB concentrations in fresh fillets were 2,438, 10,116, 8,491, and 12,952pg/g in the four systems (P<0.001). The congener 153 was the most represented in all rearing systems. TEQ concentrations for the dioxin-like congener no. 118 were 50 to 200 times lower than the maximum admitted value. Total concentration of indicator congeners of PCB was poorly correlated with fish slaughter weight (R2=0.17), while highly correlated with fat concentration of fish (R2=0.75)

Epizootic Rabbit Enteropathy (ERE) is an important syndrome that occurred in European rabbit farms the last ten years and is linked to massive deaths, mainly during the fattening period. ERE was first observed in France, in 1997, and was quickly spread in all rabbit-breeding European countries, e.g. Italy, Spain, Portugal, Belgium, Netherlands, Hungary, Germany, Great Britain and Greece. In Greece, ERE has been clinically identified since 2003 in several commercial rabbit farms, causing severe economic loss in country's rabbit farming sector. In other continents no ERE cases have been reported up to today. ERE is characterized by very high mortality, reaching up to 30-80%. The exact etiology of the syndrome is still unclarified, although in several cases, various known pathogens have been isolated, e.g. coccidia, E. coli, Clostridium spp., Enteroviruses, Rota, virus. Treatment is only symptomatic and is mainly based on the use of antibiotics. Prescribed antibiotics against ERE are thiamouline and tylozine. But, the antibiotic of choice is the water soluble bacitracin, which is exclusively permitted only for use in rabbit farms.