Antonia Lestingi

Use of dietary mannanoligosaccharides during rabbit fattening period: Effects on growth performance, feed nutrient digestibility, carcass traits, and meat quality

This study was conducted to compare the effects of mannanoligosaccharides (MOS) and antibiotics as a dietary supplement on ADG, ADFI, G:F, and feed nutrient digestibility of rabbits during the fattening period, as well as on carcass traits and meat quality. A total of 512, sixty-day-old hybrid Hyla rabbits were randomly divided into 4 treatment groups based on BW and sex. The 4 treatment groups consisted of a control group and 3 MOS groups. The control group was fed a diet that contained apramycin (50 mg/kg), but diets for the 3 MOS groups contained 0.5, 1.0, or 1.5 g/kg of MOS instead of apramycin. The rabbits were fed experimental diets for 22 d and all rabbits were slaughtered at the end of the experiment when they were 82 d old. Individual BW and feed intake per cage were recorded weekly for 32 cages randomly chosen per group (64 rabbits) to calculate ADG, ADFI, and G:F. The apparent digestibility values of OM, CP, ether extract, crude fiber, NDF, ADF, cellulose, and hemicellulose were measured using AIA as an inert marker. Carcass data were collected from 16 randomly chosen rabbits (8 males and 8 females) per group. The control group had less G:F (P < 0.001) than the MOS groups and a linear increase (P < 0.001) in G:F was observed as the concentration of MOS increased from 0.5 to 1.0 and 1.5 g/kg. The apparent digestibility of DM, OM, crude fiber, NDF, ADF, cellulose, and hemicellulose increased (quadratic, P < 0.05) as the concentration of MOS in the diets increased. The apparent digestibility of DM, OM, CP, crude fiber, NDF, ADF, cellulose, and hemicellulose was also greater (P < 0.05) in the diets containing MOS than in the control diet and the digestibility of these nutrients was greater (P < 0.05) in the diet containing 1.5 g/kg of MOS compared with the control diet. The concentration of palmitic acid, stearic acid, and SFA was greater (P < 0.05) in the meat from rabbits fed the control diet than rabbits fed the MOS diets. The concentration of stearic acid decreased (quadratic, P < 0.05) in the meat of rabbits as the concentration of MOS in the diet increased. Meat from rabbits fed diets containing MOS also had greater contents of oleic acid (P < 0.05) and MUFA (P < 0.001) than those rabbits fed the diet containing apramycin. The thrombogenic index was greater (P < 0.05) in the meat from the control group rabbits than the MOS group rabbits. In conclusion, the inclusion of MOS in diets fed to rabbits during the fattening period may improve G:F and modify the fatty acid profile of meat.

Effects of tillage and nitrogen fertilisation on triticale grain yield, chemical composition and nutritive value.

BACKGROUND Given the interest in the development of cultivation systems with low agronomic input and environmental impact, the aim of this study was to determine the influence of tillage system (conventional tillage (CT), two-layer tillage (TT), surface tillage (ST) and minimum tillage (MT)) and nitrogen (N) fertilisation rate (0, 50 and 100 kg ha(-1)) on triticale grain and protein yields, chemical composition and nutritive value. RESULTS There were no significant differences among tillage treatments in grain and protein yields. ST resulted in significantly higher crude protein (CP) and true soluble protein (TSP) contents as well as in vitro crude protein digestibility (CPD). Neutral detergent fibre concentration was significantly higher with ST than with MT, and this led to a small reduction (2 g kg(-1) dry matter (DM)) in in vitro true DM digestibility (IVTDMD). N fertilisation significantly increased grain and protein yields as well as CP, non-protein nitrogen and TSP contents and CPD. IVTDMD was significantly lower with 0 kg N ha(-1) than with 50 and 100 kg N ha(-1). CONCLUSION Reducing tillage intensity improved the CP content and CPD of triticale grain. The application of 50 kg N ha(-1) resulted in good grain quality parameters and grain and protein yields.

Effect of dietary mannan‐oligosaccharides on in vivo performance, nutrient digestibility and caecal content characteristics of growing rabbits

To evaluate the effect of mannan-oligosaccharides (MOS) on in vivo performance, nutrient digestibility, fermentation characteristics and caecal microbial populations of rabbits, 144 thirty-five days old hybrid Hyla were equally divided into three groups, one of which was fed the same diet without additives (control group), one with antibiotics (colistin sulphate, 144 mg/kg; tylosin, 100 mg/kg; oxytetracyclin, 1000 mg/kg) and one with MOS (1 g/kg of diet). Mortality rate, live weight, feed intake and feed conversion ratio were recorded up to 62 days of age. At 60 days nutrient digestibility was measured by acid insoluble ash method. The caecal content of 10 rabbits per group was collected at 62 days and analysed for volatile fatty acids production, ammonia content and microbial count. Rabbits from the control group had a significantly (p < 0.01) lower body weight at 62 days (1638.9 g vs. 1779.4 g and 1862.5 g, respectively for the control, MOS and antibiotic groups) while the antibiotic group showed a higher (p < 0.05) feed intake than the control group (127.9 g/day vs. 109.3 g/day). Rabbits from the MOS group had a higher apparent digestibility of cellulose (34.27% vs. 29.61% and 27.49%, respectively for the MOS, control and antibiotic groups) and, as a consequence a higher level of acetate in the caecal content (39.93 mmol/l vs. 34.21 mmol/l and 23.09 mmol/l, respectively for the MOS, control and antibiotic groups). Caecal microflora of the MOS group rabbits also had a higher fermentative activity in respect of protein source, as demonstrated by the higher productions of branched chain fatty acids. MOS and antibiotics significantly reduced the colonies of Coliformis (2.32 vs. 3.20 vs. 2.40 logCFU/g, respectively for the MOS, control and antibiotic groups, p < 0.01). Mannan-oligosaccharides at 1 g/kg of diet can be used as an alternative to antibiotics during the rabbits growth period.

Effects of water restriction on growth performance, feed nutrient digestibility, carcass and meat traits of rabbits

The study investigates the effects of a post-weaning water restriction on performance, nutrient digestibility, carcass traits and meat quality of 84-day-old rabbits. A total of 1388 weaned rabbits (35 days) were randomly divided into two groups on the basis of BW and sex. The two groups were fed the same diets ad libitum both in the post-weaning (35 to 60 days) and fattening (61 to 84 days) periods. In the post-weaning period, one group (AL) also received drinking water ad libitum, whereas the other (WR) had a water restriction from 35 to 41 days 2 h/day; from 42 to 48 days 2.5 h/day; from 49 to 55 days 3 h/day; and from 56 to 60 days 4 h/day. During the fattening period, both groups had water-free access. Individual live weights and feed intake per cage were recorded weekly for 32 cages randomly chosen per group (64 rabbits) to calculate the BW gain, feed intake and feed conversion ratio (FCR). The apparent digestibility values of nutrients were measured using acid-insoluble ash. Carcass data were collected from 16 rabbits (8 males and 8 females) per group selected for similar final BW in both groups. Mortality from 35 to 60 days was higher in the AL group (10.1% v. 5.2%, for AL and WR, respectively, P < 0.0001). BW gain was higher for the AL group during both the post-weaning (+22.4%, P < 0.01) and the entire period (+7.5%, P < 0.05). Water restriction reduced feed intake both in the post-weaning (-17.4%, P < 0.0001) and in the entire period (-9.9%, P < 0.05). During the fattening period, FCR was lower for the WR group (5.15 v. 5.75 g/g, for WR and AL, respectively, P < 0.05). The apparent digestibilities of dry matter, organic matter, NDF, ADF and cellulose were greater in the restricted rabbits (+4.7%, +4.5%, +10.2%, +18.8% and +12.8%, P < 0.01, P < 0.01, P < 0.05, P < 0.01, P < 0.05, respectively). Perirenal and scapular fat percentages were higher in the AL rabbits (+30.7% and +116.6%, P < 0.01 and P < 0.001, respectively). Water restriction increased saturated fatty acids (C16:0, +12.9%, P < 0.05), lauroleic acid (C12:1, +75.0%, P < 0.01), n-3 polyunsaturated fatty acids (C20:5, +50.0%, P < 0.01 and C22:5, +16.6%, P < 0.05) and the n-3/n-6 ratio (+28.6%, P < 0.05). The applied water restriction between 35 and 60 days executed during the winter months improved the digestive health of rabbits, with no negative effects on carcass traits, or physical and chemical meat characteristics. However, from the animal welfare point of view, a water restriction can be criticized as a method to restrict feed intake.

Comparison between carcasses of artificially suckled I.H.D.H. (Italian Heavy Draught Horse) foals slaughtered at 6 months and traditional carcasses obtained by foals slaughtered at 11 and 18 months

Abstract Aim of the study was the evaluation of a innovative I.H.D.H. carcass production system in order to improve the conditions for mare’s milk production. In the trial were used 18 foals, subdivided in three randomized groups of 6 animals each. Every group was slaughtered at a different age: 6 months (artificially suckled), 11 months and 18 months (naturally suckled, following traditional rearing systems). Six months old foals carcasses were characterized by 75.59 % of lean, 12.79 % of fat and 11.64 % of bone. Six months foals carcasses showed the lean end the fact respectively higher (P<0.001) end lower (P<0.001) than 18 months ones (P<0.001), and the bone higher than 11 months foals (P<0.001). Six months hind quarter incidence was 65.00 %, more than found for 18 months carcasses (P<0.001). Moreover, 6 months carcasses showed an first quality cuts incidence higher than 11 months foals (P<0.01).

Effect of spray application of Lactobacillus plantarum on in vivo performance, caecal fermentations and haematological traits of suckling rabbits

Two days before kindling, 228 New Zealand White rabbit does were homogeneously divided into two groups (114 does per group) and fed the same diet. After delivery, the litters were equalized to 8 pups. From 1 to 35 days of age (weaning), the control group (CONT) did not receive any treatment while in the experimental group (LAC) the nests were sprayed with a commercial product containing lyophilized Lactobacillus plantarum dissolved in water (12 g/L). L. plantarum was sprayed on the litters (5 mL per rabbit) once a day during seven consecutive days after delivery. After one week of rest, the treatment was repeated for another week according to the same experimental protocol. Mortality rate, recorded on all the litters (912 rabbits per group) was significantly lower in the LAC group (9.9 vs 17.2%; P<0.05). There were no significant differences in in vivo performance of the 24 litters per group, and rabbits of both groups reached a similar weight at weaning (938 vs 932 g for LAC and CONT groups, respectively). Rabbits from the LAC group showed fermentative activity of caecal microflora (total volatile fatty acids 24.8 vs 14.5 mmol/L; P<0.01) and higher percentage of lymphocytes (73.7 vs 63.9% of total white blood cells; P<0.05). Among the microflora population of rabbit caecal content from the LAC group, it was possible to identify L. plantarum (1.25×106 CFU/g). It might be supposed that the changes in caecal microflora can affect our results and improve the sanitary status of Lactobacillus-sprayed rabbits in the period 1–35 days of age.

Effects of compost organic amendments on chemical composition and in vitro digestibility of alfalfa (Medicago sativa L.)

Abstract The following fertiliser treatments were compared during the years 2002 and 2003 on alfalfa forage (Medicago sativa L.): compost obtained from the organic fraction of the Municipal Solid Waste (MSW); olive pomace compost (OPC); mineral fertiliser (Min). All the treatments allowed a distribution of 75kg ha-1 of P2O5. Three cuttings occurred: at 168, 206 and 351 days after compost application (DAA) in 2002; 119, 152 and 320 DAA in 2003. Cumulative biomass and dry matter yields were measured during each experimental year. Furthermore, chemical composition and in vitro digestibility of dry matter (DMd), organic matter (OMd), crude protein (CPd) and NDF (NDFd) were determined. MSW treatment showed a significantly (P<0.01) higher content of ADL than OPC and Min (77.0, 66.0 and 65.0g kg-1 DM, respectively). Fertiliser treatments also affected (P<0.01) digestibility parameters. In fact, DMd and OMd values showed the same trend with lower percentages in MSW treatment than in the OPC and Min ones. The NDFd differed in all treatments having the highest value in OPC (40.1%). The results indicated that the soil distribution of organic materials offer the possibility to reduce the application of mineral fertilisers and production costs without decreasing alfalfa yield, forage chemical composition and in vitro digestibility.