562 research outputs found
Effect of dietary supplementation of lysophospholipids on productive performance, nutrient digestibility and carcass quality traits of broiler chickens
No full textAn experiment was carried out to evaluate productive performance, nutrient digestibility and carcass quality traits of broiler chickens fed diets supplemented with an exogenous emulsifier based on lysophospholipids prepared by enzymatic conversion of soy lecithin. One thousand seven-hundred and fifty-five one-day-old male Ross 308 chicks were randomly divided into three experimental groups of nine replications each: control group (CON) fed a corn–soybean basal diet, and two groups fed CON diet supplemented with constant (1 kg/ton) or variable (1–1.5 kg/ton) level of emulsifier (CONST and VARI, respectively). At the end of the trial (42 d), birds receiving the emulsifier had a statistically significant (p < 0.05) lower feed conversion rate compared to the control. Body weight and daily weight gain were only slightly influenced by lysophospholipids supplementation, while mortality and feed intake resulted similar among the groups. No statistically significant effect of the emulsifier was observed on nutrient digestibility as well as slaughtering yields, skin pigmentation and incidence of foot pad dermatitis. The results obtained in this study suggest that the use of an emulsifier based on lysophospholipids improves feed efficiency while showed limited effect on carcass quality traits
Comparison of different extenders on the quality characteristics of turkey semen during storage
No full textSemen of the domestic turkey cannot be stored longer than 6 h without a loss of fertilizing capability. The improvement of long-term liquid storage procedures of semen is important since the commercial production of turkey relies almost entirely on artificial insemination. Therefore, studies improving storage regimens would allow longer storage and consequently hen fertility (Iaffaldano and Meluzzi, 2003). Since the search for an optimal extender composition for semen storage is still in progress, the aim of this paper has been to study the effects of different extenders on the quality of turkey semen during the storage for 48 h at 5°C
Application of omics technologies for a deeper insight into quali-quantitative production traits in broiler chickens: A review
No full textAbstract The poultry industry is continuously facing substantial and different challenges such as the increasing cost of feed ingredients, the European Union’s ban of antibiotic as growth promoters, the antimicrobial resistance and the high incidence of muscle myopathies and breast meat abnormalities. In the last decade, there has been an extraordinary development of many genomic techniques able to describe global variation of genes, proteins and metabolites expression level. Proper application of these cutting-edge omics technologies (mainly transcriptomics, proteomics and metabolomics) paves the possibility to understand much useful information about the biological processes and pathways behind different complex traits of chickens. The current review aimed to highlight some important knowledge achieved through the application of omics technologies and proteo-genomics data in the field of feed efficiency, nutrition, meat quality and disease resistance in broiler chickens
Condizioni di allevamento e prestazioni produttive. Gli effetti sulle performance zootecniche e sulla qualità del prodotto.
No full textOccurrence of Breast Meat Abnormalities and Foot Pad Dermatitis in Light-Size Broiler Chicken Hybrids
No full textOnly limited information regarding the occurrence of breast meat abnormalities and foot
pad dermatitis (FPD) in current broiler genotypes is available. Therefore, this study was conducted
to estimate the incidence and severity of breast myopathies (white striping, WS; wooden breast, WB;
spaghetti meat, SM) and FPD in two fast-growing chicken hybrids, while simultaneously recording
their growth performance. A total of 1560 one-day-old female chicks (780 for each hybrid, A and B;
12 replicates/genotype) were raised in the same environmental conditions and fed the same diet.
Productive parameters were recorded at the end of each feeding phase. At slaughter (35 d), the
occurrence of meat abnormalities and FPD was assessed on 150 breasts/genotype and on all of the
processed birds, respectively. Although comparable growth performance was observed at
slaughter, genotype B reported a significantly higher percentage of breasts without meat
abnormalities (69% vs. 39%, 75% vs. 41%, 61% vs. 37% for WS, WB and SM, respectively) and also
birds without FPD, than genotype A (53% vs. 23%, respectively). Overall, these findings highlight
the importance of better understanding the effects of the genotype and the artificial selection applied
to fast-growing chicken hybrids on the occurrence of emerging meat abnormalities and FPD even
in light-size birds
Improving welfare conditions of broiler chicken in Italy. Effects on performances, carcass and meat quality
No full textA trial was carried out to evaluate the influence of improved housing conditions for broilers kept on litter on productivity, carcass and meat quality traits. A total of 33,000 Ross 508 female broiler chickens were divided into two groups Welfare (WLF) and Standard (STD) and reared under different stocking density (14 vs. 19 birds/sq m), litter (wood shaving) amount (3.5 vs. 2.5 kg/sq m) and light:dark regimen (18:6 vs. 23:1). Birds were slaughtered at 40 or 50 d of age. Environmental temperature and humidity as well as litter moisture did not change between the two housing conditions. WLF birds reached a higher body weight but had a slight worse feed efficiency, whereas no differences were found in carcass traits. Breast meat quality evaluation showed higher moisture content and poorer water holding capacity in WLF birds
Effect of sequential feeding on nitrogen excretion, productivity, and meat quality of broiler chickens.
No full textThe aim of this trial was to investigate the effect of a 24-h cycle sequential feeding program on nitrogen excretion, incidence of foot pad lesions, productive performance, quality traits, and chemical composition of broiler chicken breast meat. In total, 1,320 one-day-old male Cobb 700 chicks were split into 2 groups of 6 replicates each. From 1 to 10 d of age, all of the chickens received the same prestarter diet (ME 3,058 kcal/kg; CP 226 g/kg). The control group (CON) received 1 of 3 diets for 24-h cycles: starter (ME 3,162 kcal/kg; CP 205 g/kg), grower (ME 3,224 kcal/kg; CP 192 g/kg), and finisher diets (ME 3,242 kcal/kg; CP 184 g/kg) from d 11 to 18, 19 to 38, and 39 to 44 of age, respectively. The sequential feeding group (SF) received the same diets as the CON birds for half of the day, and then low-protein and isoenergetic diets for the remaining half of the day. Birds submitted to the SF program showed better utilization of dietary nitrogen compared with the CON birds (45.0 vs. 46.1% of N excreted/N ingested, respectively; P < 0.05), and consequently the SF birds had lower nitrogen excretion compared with the CON birds (24.8 vs. 25.9 N g/kg of BW, respectively; P < 0.01). The SF birds exhibited a significantly lower incidence (7 vs. 13%) of foot pad lesions and consumed 70 g of feed/bird more than the CON birds. The SF birds also had a significantly higher feed conversion rate compared with that of the CON birds (1.84 vs. 1.78, respectively). The SF breast meat exhibited a significantly lower ultimate pH, a higher cook loss, and a lower lipid content compared with the values found for the CON group. The SF approach in poultry husbandry had positive repercussions on environmental and animal welfare aspects, but adversely affected feed efficiency, and altered some meat traits (mainly pH and cook loss)
The role of histidine dipeptides on postmortem acidification of broiler muscles with different energy metabolism
No full textIt is generally held that the content of several free amino acids and dipeptides is closely related to the energy-supplying metabolism of skeletal muscles. Metabolic characteristics of muscles are involved in the variability of meat quality due to their ability to influence the patterns of energy metabolism not only in living animal but also during post-mortem time. Within this context, this study aimed at establishing whether the concentration of histidine dipeptides can affect muscle post-mortem metabolism, examining the glycolytic pathway of three chicken muscles (Pectoralis major, extensor iliotibialis lateralis and gastrocnemius internus as glycolytic, intermediate and oxidative-type, respectively) selected based on their histidine dipeptides content and ultimate pH. Thus, a total of 8 carcasses were obtained from the same flock of broiler chickens (Ross 308 strain, females, 49 days of age, 2.8 kg body weight at slaughter) and selected immediately after evisceration from the line of a commercial processing plant. Meat samples of about 1 cm3 were excised from bone-in muscles at 15, 60, 120 and 1,440 min post-mortem, instantly frozen in liquid nitrogen and used for the determination of pH, glycolytic metabolites, buffering capacity as well as histidine dipeptides content through 1H-NMR. Overall results suggest that glycolysis in leg muscles ceased already after 2 h post-mortem, while in breast muscle continued until 24 h, when it exhibited significantly lower pH values (P<0.05). However, considering its remarkable glycolytic potential, Pectoralis major muscle should have exhibited a greater and faster acidification, suggesting that its higher (P<0.05) histidine dipeptides’ content might have prevented a potentially stronger acidification process. Accordingly, breast muscle also showed greater (P<0.05) buffering ability in the pH range 6.0-7.0. Therefore, anserine and carnosine, being highly positively correlated with muscle’s buffering capacity (P<0.001), might play a role in regulating post-mortem pH decline, thus exerting an effect on muscle metabolism during pre-rigor phase and the quality of the forthcoming meat. Overall results also suggest that total histidine dipeptides content along with muscular ultimate pH represent good indicators for the energy-supplying metabolism of chicken muscles
Welfare of broiler chickens
No full textBroiler chickens have been selected for their rapid growth rate as well as for high carcass yields, with particular regard to the breast, and reared in intensive systems at high stocking density ranging from 30 to 40 kg live weight/m2. These conditions lead to a worsening of the welfare status of birds. In Europe a specific directive for the protection of broiler chickens has been recently approved whereas in Italy there is not yet any regulation. The EU directive lays down minimum rules for the protection of chickens kept for meat production and gives indications on management practices with particular focus on stocking density, light regimen and air quality, training and guidance for people dealing with chickens, as well as monitoring plans for holding and slaughterhouse. In this review the rearing factors influencing the welfare conditions of birds are described and detailed information on the effects of stocking density, light regimen, litter characteristic and air quality (ammonia, carbon dioxide, humidity, dust) are provided. Moreover, the main health implications of poor welfare conditions of the birds, such as contact dermatitis, metabolic, skeletal and muscular disorders are considered. The behavioural repertoire, including scratching, dust bathing, ground pecking, wing flapping, locomotor activity, along with factors that might impair these aspects, are discussed. Lastly, farm animal welfare assessment through physiological and behavioural indicators is described with particular emphasis on the “Unitary Welfare Index,” a tool that considers a wide range of indicators, including productive traits, in order to audit and compare the welfare status of chickens kept in different farms
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