Showing papers by "Cesare Castellini published in 2009"

Effect of rearing system and season on the performance and egg characteristics of Ancona laying hens

Abstract: Productive performance and egg characteristics of Ancona laying hens reared under three different rearing systems (conventional, organic and organic-plus) were compared during an experimental period of one year. Three-hundred-sixty Ancona female chicks at 28 days of age were divided in three groups and assigned to different rearing systems. The organic group had 4m2 pasture/hen according to the requirements imposed by the EC Regulation 1804/99, whereas the organic-plus group had a larger grass paddock (10m2/hen). The Control group was reared in cages under standard housing conditions. The following egg characteristics were recorded and analysed during the year-long cycle: egg weight and egg mass laid/d, weight of egg components, shell thickness, Haugh index and yolk colour. Egg quality was affected by the pasture available. The hens that ingested grass (organic-plus), produced eggs with higher shell weight and percentage, darker yolk colour and higher α-tocopherol, carotenoid and polyphenol contents. The other egg traits were not affected by rearing system.

Effect of genotype and rearing system on chicken behavior and muscle fiber characteristics

Abstract: The effect of the organic production system and genotype on chicken behavior and muscle fiber characteristics was assessed. Three hundred day-old male chicks from slow-growing (Leghorn), medium-growing (Kabir), and fast-growing (Ross 208) genotypes were assigned to 2 different production systems: conventional, housing in an indoor pen (0.12 m(2)/bird); and organic, housing in an indoor pen (0.12 m(2)/bird) with access to a grass paddock (4 m(2)/bird). Behavioral observations were recorded from 73 to 80 d of age in the morning and afternoon. At 81 d of age, blood samples were collected to measure lactate dehydrogenase and creatine kinase, and 20 birds per strain and rearing system were slaughtered. Samples of pectoralis major, ileotibialis lateralis, and semimembranosus muscles were obtained for histological evaluations. Behavioral observations showed that genetic selection of animals for a better growth rate modified their behavior, reducing kinetic activity. Indeed, Leghorn birds were characterized by moving activities, whereas Kabir and Ross strains were discriminated on the basis of their lying, standing, and eating activities, and these activities were strongly associated with energy conservation, growth, and muscle fiber characteristics. Fiber characteristics and muscle enzyme functions were affected by rearing system only in animals adapted to the organic system. Interesting results relative to Leghorn chickens are the presence of alpha-Red fiber in breast muscle and the increased cross-sectional area of the ileotibialis lateralis muscle, which together with behavioral data could affirm that this genotype is the most adapted to the organic rearing system.

Influence of genotype and feeding on chemical composition of organic chicken meat

Abstract: The aim of this study was to evaluate the effects of different genotypes and of feeding on meat chemical composition, including fatty acid profile, of chickens reared under organic conditions Twomeat–typefast-growing(FG) andmedium-growing(MG), andoneegg-typeslow-growing(SG) wo meat–type fast-growing (FG) and medium-growing (MG), and one egg-type slow-growing (SG) strains were assigned to 2 different diets differing for the protein source: soybean (SB) and faba bean (FB) in partial substitution of soybean Genotypemarkedlyaffectedthemeatchemical composition Genotype markedly affected the meat chemical composition SG breast and thigh meat showed lower content of lipids (P<001) than FG Thehighestproportions he highest proportions of polyunsaturated fatty acids (PUFA) n-6 and n-3 and the lowest proportion of monounsaturated (MUFA) (P<001), as well as the lowest ratio of PUFA n6/n3 (P<001) were found in SG breast and thigh meat MG showed always intermediate values Asforfeeding, FBtreatmentproducedonlya As for feeding, FB treatment produced only a slight increment of protein in breast and a decrease of fat and ash in thigh meat Total PUFA and PUFA n-6 resulted lower in both thigh and breast meat of FB groups compared to SB (P<001)

Effect of genotype and rearing system on the native immunity and oxidative status of growing rabbits

Abstract: To investigate the effects of genotype and rearing system on innate immunity and oxidative status, 40 weaned commercial hybrid (H) rabbits and 40 rabbits of a local population (LP) were assigned to two rearing systems: cage (17 rabbits/m2) and pen (1x2 m, 10 rabbits/m2). Rearing H rabbits in pen resulted in a higher lysozyme concentration (P<0.05), an increased bactericidal ac- tivity (P<0.05) and a lower complement haemolytic activity (P<0.05) with respect to those reared in cage. Opposite results were obtained for LP rabbits. In addition, genotype H was more susceptibility to inflammation than LP in pen, whereas genotype LP suffered more in cage. A higher lipid (P<0.05) and protein (P<0.05) oxidation was found in Longissimus dorsi and Biceps femoris of rabbits H in pen compared to those in cage. An opposite trend was observed for LP rabbits. In cage, LP rabbits were more susceptible to oxidative stress than H rabbits. Taken together, our results show that immune and oxidative resistance ascribed to a specific genotype are important factors to be considered when a specific rearing system should be adopted. Considering this, rabbit LP seem to better adapt to larger spaces during growing.

Evaluation of intestinal bacterial flora of conventional and organic broilers using culture-based methods

Abstract: The major bacteria colonizing the intestinal tract (ileum and caecum) of organic (O) and conventional (C) chickens were counted, isolated and identified by conventional methods. Chickens were obtained from 7 conventional and 7 organic chicken farms (n=203). Intestinal sampling was performed at different ages, every 10 days, starting at 20 days until 40 and from 20 days to 80 days of age, respectively, for conventional and organic birds. Statistical analysis was performed on two separate data sets (40 days of age and all ages).The comparison of C vs O systems was analyzed with univariate and multivariate procedures. There were large differences in bacterial counts in relation to the portion of intestine, the rearing system and the farms. In the ileum of conventional birds Enterobacteria were higher than in organic birds (7.03 vs 6.09 CFUxlog/g; P<0.05), whereas the contrary was observed for Lactobacilli (6.75 vs 7.07 CFUxlog/g; P<0.05). With respect to the other microflora, the effect of farm probably masked possible differences. The effect of rearing system was more visible in the caecum than in the ileum: Enterobacteria levels were higher in C than in O chickens (7.42 vs 7.05 CFUxlog/g; P<0.01), whereas Enterococci (7.65 vs 6.55 CFUxlog/g; P<0.05), Lactobacilli (7.85 vs 7.31 CFUxlog/g; P<0.05) and total aerobia (8.12 vs 7.66 CFUxlog/g; P<0.01) counts were higher in organic chickens. Multivariate analysis of caecum microflora showed the possibility of discriminating the rearing system. In the ileum of conventional birds Enterobacteria and total aerobia increased with age, while Lactobacilli decreased. In the O system, Enterobacteria, Lactobacilli and total anaerobia showed a similar trend, whereas total aerobia and Enterococci showed the opposite trend. A similar situation was observed in the caecum. Further investigations are necessary to better assess the role and effect of the enteric flora on the productive performance and on the health status of reared chickens.

Faba bean (Vicia faba var. minor) as a protein source for organic chickens: performance and carcass characteristics.

Abstract: The ban of transgenic feed and synthetic amino acids in organic chicken diets has made necessary to find protein-rich feedstuffs which do not alter productive performance. The effect of the faba bean (Vicia faba var. minor) as a partial substitute for soybean on the performance and carcass traits of slow-growing chickens of both sexes reared under the organic method was assessed. The experiment was carried out in the spring and autumn; one thousand birds per season were split into 8 groups (4 groups of males and 4 groups of females, each duplicated) and fed a double phase diet: a common starter diet for 20 days and two different growing-finisher diets containing either soybean (24%; S) or faba bean (16%; F) till the end of the rearing period (120 d). Average values of final live weight, feed intake and daily weight gain were significantly affected by sex, being higher in males than in females; the diets affected performance only in the 21-60 days of age period when the F group grew less and had poorer feed efficiency compared to the S group. Successively, the compensatory growth eliminated differences in slaughter weight. Regarding carcass traits, the diet affected only the ready- to-cook carcass percentage and the carena length, both of which were higher in S birds. Faba beans could be a valuable protein source in the diet of organic chickens when used after the critical starter period.

Serum level of hormone and metabolites in pregnant rabbit does

Abstract: The aims of this study were to compare the hormones and metabolites serum levels and the reproductive performances of nulliparous (n=100) and primiparous pregnant does submitted to artificial insemination (AI) 11 days post-partum. On the day of AI, all the does were weighed and the sexual receptivity was evaluated. The kits were weaned at 26 day. Blood samples were collect by punc- ture of the marginal ear vein from one day before AI until few days before the kindling and assayed for hormones and metabolites. The higher sexual receptivity and the fertility in nulliparous than in primiparous does confirmed the negative effect of lactation. Nulliparous does showed higher blood con- centration of leptine than primiparous, and in both the groups such level lowered during pregnancy, probably reflecting the reduction of the fat reserve. The insuline level increased during pregnancy in either groups as a consequence of the growing of the foetuses. In nulliparous does the cortisol, NEFA and T3 concentrations were higher than primiparous does. The glucose levels were similar in both the groups probably due to the homeostatic mechanisms controlling the glycemia. Hormonal and metabo- lite analyses represent a good tool for understanding the physiological mechanisms required to meet higher reproductive performance.