Showing papers by "Gerolamo Xiccato published in 2013"

A meta-analysis on the role of soluble fibre in diets for growing rabbits

Abstract: In this review, the methods used to measure fibre and soluble fibre fractions are briefly presented and the effects of the soluble fibre content in diets for growing rabbits reviewed by a meta-analysis of studies available in literature, with the aim of elucidating the relationships with other dietary nutrients. Soluble fibre was assumed as the difference between total dietary fibre (TDF) and neutral detergent fibre (NDF), as it is simple to obtain and has been measured in numerous studies. Dietary soluble fibre content affects the digestive utilisation of soluble and insoluble fibre fractions and its increase is associated with reduced mortality in growing rabbits affected by epizootic rabbit enteropathy. This effect could be attributed to the high fermentability of soluble fibre, the consequent changes in the intestinal microbiota and an enhanced gut barrier function just after weaning. A supply of 12-14% of soluble fibre (as-fed) is recommended in diets for post-weaning and growing rabbits containing around 30% NDF and 18% acid detergent fibre. The positive effects of increasing dietary soluble fibre are linked to the use of sugar beet pulp as primary source of soluble fibre and should be confirmed with other sources of soluble fibre.

Housing of growing rabbits in individual, bicellular and collective cages: fear level and behavioural patterns

Abstract: During growth (27 to 75 days of age), a total of 384 rabbits were kept in 72 individual cages, 48 bicellular cages (2 rabbits/cage) and 24 collective cages (9 rabbits/cage). To evaluate the effects of the housing system on the fear level and behavioural patterns of rabbits at the two ages (39 to 45 days and 66 to 73 days), a tonic immobility test and an open-field test were conducted and their behaviour was video recorded. In the tonic immobility test, the number of attempts to induce immobility (1.38) was lower, and the duration of immobility (47.8 s) was higher (0.05 < P < 0.01) in the rabbits housed in individual cages than in those kept in bicellular (1.72 attempts and 25.0 s of immobility) and collective cages (1.99 attempts and 25.0 s of immobility). During the open-field test, the rabbits from individual and bicellular cages showed higher latency (38.8 and 40.3 v. 27.0 s), a lower number of total (73.3 and 81.7 v. 91.9) and central displacements (3.6 and 2.8 v. 5.4) and a shorter running time (11.8 and 13.6 s v. 17.7 s) and the time biting the pen (5.5 and 9.1 s v. 28.2 s) compared with the rabbits kept in collective cages (0.05 < P < 0.001). During the 24-h video recording, the rabbits in individual and bicellular cages spent less time allogrooming (0.34% and 0.19% v. 1.44%), moving (0.74% and 0.60% v. 1.32%) and running (0.08% and 0.03% v. 0.21%) than the rabbits in the collective cages (0.01 < P < 0.001). The lowest numbers of alerts and hops were observed in the rabbits kept in bicellular cages. With increasing age, a lower number of rabbits were sensitive to the immobility test and more rabbits entered the pen spontaneously during the open-field test (P < 0.001). In conclusion, the rabbits in individual cages exhibited the highest fear level and incomplete behavioural patterns; the rabbits housed in collective cages showed the lowest fear levels and had the possibility of expressing a wider range of behaviour; and the rabbits in bicellular cages exhibited an inconsistent pattern of fear in the tonic immobility and open-field tests. Probably, these rabbits were in a less stressful condition compared with animals in individual cages because social contacts were allowed, even if freedom of movement was more limited.

Housing of growing rabbits in individual, bicellular and collective cages: growth performance, carcass traits and meat quality

Abstract: During growth (from 27 to 75 days of age), 384 rabbits were kept in different types of wire-net cages: 72 individual cages (72 rabbits; 10 animals/m2), 48 bicellular cages (96 rabbits; 2 rabbits/cage; 18 animals/m2) and 24 collective cages (216 rabbits; 9 rabbits/cage; 18 animals/m2). The rabbits housed in individual cages showed higher daily weight gain both during the fattening period (from 52 to 75 days of age) and during the whole period of growth (43.0 v. 41.8 and 41.5 g/day; P < 0.05), and they had a higher final live weight at 75 days of age (2678 v. 2619 and 2602 g; P < 0.05) compared with the rabbits in the bicellular and collective cages, respectively. Rabbits in individual cages ingested more feed (133 v. 127 and 126 g/day; P < 0.01), but the feed conversion did not differ significantly among rabbits housed in the three types of cages. At slaughter, the carcass traits and meat quality were weakly affected by the housing system. The transport losses were higher in rabbits kept in individual and bicellular cages compared with those reared in collective cages (3.1% and 2.9% v. 2.2%; P < 0.01). In rabbits kept in individual cages, the hind leg muscle to bone ratio was higher (6.35 v. 6.19 and 5.91; P < 0.05) compared with the bicellular and collective cages, respectively. The pH and colour of the longissimus lumborum did not change with the housing system, while the b* index of the biceps femoris was lower (3.04 and 3.32 v. 4.26; P < 0.001) in the rabbits kept in individual and bicellular cages, respectively, than in those kept in collective cages. In conclusion, the rabbits housed in individual cages showed higher daily growth than rabbits kept in bicellular or collective cages, but they had a similar feed conversion and carcass quality. Differently, neither in vivo performance nor slaughter results differed among the rabbits kept in bicellular cages or in collective cages. The meat colour may be affected by the housing system, but to an extent that is hardly perceivable by the final consumer.

Increasing dietary energy with starch and soluble fibre and reducing ADF at different protein levels for growing rabbits.

Abstract: Summary Th e eff ect of increasing dietary energy by increasing both starch (14% to 20%) and soluble fi bre (9.6% to 11.6%) and decreasing ADF content (21% to 13%) at two crude protein levels (14% and 15%) was assessed on health, growth performance, caecal fermentative activity, gut mucosa traits, and carcass and meat quality of growing rabbits reared from 34 to 76 days of age. At weaning, 306 rabbits were divided into six groups and fed ad libitum six diets formulated according to a bi-factorial arrangement with 3 (starch+soluble fi bre)/ADF ratio (L=1.2; M=1.8; H=2.8) x 2 protein levels. Th e contemporary increase of dietary starch and soluble fi bre and the reduction of ADF linearly increased the digestibility of dry matter, energy and all nutrients, decreased feed intake and improved feed conversion (3.65 to 2.76 in rabbits fed diets L and H; P<0.001); it increased morbidity (P=0.09) but did not aff ect mortality due to epizootic

Performance of growing rabbits in bicellular cages and collective pens

Abstract: The study aimed at evaluating whether housing growing rabbits in pairs in bicellular cages (18 animals/m 2 ) or in group of 20 to 54 animals kept in small (1.40 x 1.20 m) or large pens (1.40 x 2.40 m) with wooden floor at low (12 animals/m 2 ) or high stocking density (16 animals/m 2 ) might influence growth performance and slaughter traits. The rabbits kept in bicellular cages showed higher final live weight (2839 vs. 2655 g; P<0.01), daily weight gain (+10%; P<0.01), and feed intake (+11%; P<0.001), without differences for feed conversion ratio, compared with the rabbits housed in collective pens. At slaughter, the former rabbits also displayed higher dressing percentage (60.5% vs. 59.6%), dissectible fat proportion (3.0% vs. 2.1% reference carcass) and hind leg muscle-to-bone ratio (7.53 vs. 6.63) (P<0.001) compared with the group-housed rabbits. Within the collective pens, the increase in the stocking density from 12 to 16 rabbits/m 2 increased only the slaughter dressing percentage (59.4% vs. 59.8%; P=0.05), whereas no significant effect of pen size was measured. In conclusion, rearing rabbits in collective pens impaired growth performance and slaughter results compared to rabbits kept in bicellular cages, regardless of stocking density or pen size.