bird density stress markers and growth performance in the italian chicken breed milanino

Summary The Milanino is an Italian chicken breed included in a conservation project run by the University of Milan. It is characterized by good fertility, heavy body weights, high adaptation ability to adverse climate conditions, and disease resistance. Because of these characteristics, the Milanino could represent an important genetic resource for alternative production systems. This research was aimed at studying the effect of bird density on growth and slaughter performance, as well as stress response in Milanino chickens kept in outdoor pens. One hundred and sixty Milanino chickens were randomly assigned to 2 experimental groups kept at different densities (2 m2/bird and 8 m2/bird) and were slaughtered at 185 days of age. Growth and slaughter performance and stress condition were recorded. The interaction bird density * sex * age significantly affected body weight and an opposite trend was found between females and males: heavier females were found in the high-density group, while heavier males were found in the low-density group. Bird density did not affect carcass weight data. The stress marker (H/L ratio) was significantly higher in birds kept at the higher density (2 m2/bird). In conclusion, the Milanino provided satisfactory growth performance with different rearing density but the lower density, 8 m2/bird, should be preferred to minimize welfare problems for male birds

egg quality and productive performance of laying hens fed different levels of skimmed milk powder added to a diet containing lactobacillus acidophilus

Abstract The current trial was carried out on a commercial poultry farm to study the effect of skim milk powder (SMP) added to a diet containing Lactobacillus acidophilus on performance and egg quality of laying hens from 20 to 49 wk of age. A total of 2,400 Hy-Line W-36 laying hens were housed in 600 unenriched cages (4 hens each) located over 4 tier levels. Animals were assigned to 1 of 3 experimental treatments (0, 3, and 4). The laying hens assigned to treatments 3 and 4 received a diet enriched respectively with 3 and 4% SMP, whereas the animals in treatment 0 were fed a diet without SMP. All diets, moreover, were supplemented with L. acidophilus D2/CSL. Hen performance was determined throughout the experimental period and egg quality was measured on 30 eggs per treatment every week. Results showed that productive performance in terms of egg production, egg weight, and feed conversion ratio was not influenced by SMP at 3 or 4% of the diet. Egg quality was significantly affected by SMP included at 3 or 4% of the diet. Eggs from treatments 3 and 4, in fact, displayed higher shell thickness than those from treatment 0 (

Free-Range Rearing Density for Male and Female Milanino Chickens: Growth Performance and Stress Markers

The Milanino is a heavy Italian chicken breed and represents an important genetic resource for alternative production systems. Due to the absence of standard management guidelines for local chicken breeds, this study aims to determine the space requirement to achieve a good equilibrium between growth performance and stress response in Milanino chickens reared according to a separate-sex free-range program. A total of 140 birds (70M:70F) were reared in outdoor pens from 75 to 235 d of life according to the following experimental groups (35 birds/group): (M2) males in 2 m(2)/bird; (F2) females in 2 m(2)/bird; (M10) males in 10 m(2)/bird; (F10) females in 10 m(2)/bird. Growth performance and stress condition were recorded. Bird density affected male body weight, that was higher at the lower density of 10 m2/bird. In contrast, females showed a consistent growth rate irrespective of the bird density suggesting lower space requirements. An overall good adaptability of the breed to the separate-sex free-range system was found, irrespective of both sex and bird density. Moreover, the stress markers values assessed at the end of the growing period suggest the ability of Milanino birds to respond well to environmental stressors. The results provided in this report will be implemented into free-range management guidelines for meat production in the Milanino breed: the separate-sex rearing is recommended during the growing period in outdoor pens and the bird density has to be planned according to the sex

Effect of lycopene on fowl sperm characteristics during in vitro storage

Chicken and turkey sperm contains high amounts of PUFAs and spontaneous peroxidation occurs during in vitro storage. For this reason, the addition of antioxidant to diluent takes special interest in the improvement of commercial extenders. The effects of lycopene added to fowl sperm was the object of this study. Semen of 13 roosters, from 36th to 43rd week of age, was collected and pooled. Fresh semen was evaluated at 0 h time and 4 aliquots of 500\u3bcL were diluted to 2 7109 sperm/mL by diluent Lake or Lake and lycopene at different concentrations (500\u3bcg/mL, 250\u3bcg/mL and 100\u3bcg/mL) and stored at 13/14\ub0C in a water bath for 24 h. Motility, forward progressive motility and viability were evaluated at 1 h, 6 h and 24 h. Sperm motility and forward progressive motility were not significantly (P > 0.05) affected by lycopene inclusion. For 500\u3bcg/mL treatment the viability parameter was significantly (P < 0.05) higher than for Lake or Lake with 250\u3bcg/mL and higher for Lake with 100\u3bcg/mL. Besides, among the treatments the 500\u3bcg/mL of lycopene reduced the viability loss between 6 h and 24 h of incubation. The results of the present study suggest positive effects of lycopene supplementation to extender on fowl sperm survival during liquid storage

Sperm quality changes during equilibration time at 4 \ub0C before cryopreservation of chicken semen

Cryopreservation procedure includes many steps and each one may affect sperm quality and then sperm viability after thawing. The aim of our experiment was to study if sperm quality changes occur during the initial steps of the cryopreservation pellet procedure in chicken semen. The initial steps, dilution rate and equilibration time at 4 \ub0C, were studied. Ejaculates were collected from Mericanel della Brianza male breeders (n. 18), pooled and splitted into two aliquots, one diluted 1:2 and the other one 1:3 in prefreezing Lake\u2019s diluent. Diluted aliquots were equilibrated at 4 \ub0C for 40 minutes. The following semen parameters were measured on fresh semen (T0), after 20 (T20) and 40 (T40) minutes: motility (%), VCL (\ub5m/sec), VSL (\ub5m/sec), LIN (%), ALH (\ub5m), normal and abnormal viable sperm, dead sperm and damaged sperm (%). The main effects, dilution rate and equilibration time, and the relative interaction were studied by repeated measure analysis of variance. Sperm quality was significantly affected by the equilibration time, whereas the dilution rate and the interaction were not significant. The proportion of abnormal viable sperm significantly increased from T0 to T20 (15 to 21%). Other changes occurred from T20 to T40: the proportion of viable normal sperm significantly decreased compared to T0 (69 to 62%), and the VCL (131 to 119 \ub5m/sec) and ALH (11 to 9 \ub5m) values also significantly decreased. No further decrease in the proportion of abnormal viable sperm from T20 to T40 was recorded. Very similar trend in sperm quality was found with both dilutions during equilibration time at 4 \ub0C. The variability found in semen concentration among ejaculates suggests the need to improve the criteria of dilution to standardize semen processing. In conclusion, short equilibration time, such as 20 minutes, in prefreezing diluent at 4 \ub0C is recommended to prevent a decrease in sperm quality during chicken semen processing for cryopreservation

Egg related parameters affecting fertility and hatchability in the Italian bantam breed Mericanel della Brianza

Local chicken breeds are a vital reservoir of gene resources and their conservation has a technical role related to the future development of the productive system, as well as a social-cultural role. The aim of this study was to evaluate the effects of egg weight, egg storage period and egg weight loss on hatchability of fertile eggs in the Italian bantam breed Mericanel della Brianza. Fourteen females and eight males were kept in floor pens and divided in 8 families (1M:1 or 2F) during the reproductive season (March\u2013June). Birds received a photoperiod of 14L:10D and were fed ad libitum. Egg production and egg weight were recorded daily. Eggs were divided in 4 weight groups: EW1=25%. Fertility, embryo mortality and hatchability were recorded. The mean values during the reproductive season were 82% fertility and 50% hatchability of fertile eggs. The best combination of fertility and hatchability values were recorded in EW2 and lower fertility was recorded in EW1 (P<0.05). Hatchability decreased under 50% after 10 day storage period before incubation and the best hatchability was recorded in EWL1. The present results contribute to the knowledge on reproductive parameters necessary to improve the reproductive efficiency of this Italian breed within a conservation plan

Physical parameters and fatty acids profiles in milanino, mericanel della brianza, valdarnese bianca and commercial hybrids (Gallus gallus domesticus) table eggs

The aim of the present study is to investigate the physical parameters and fatty acid composition and related nutritional parameters of market-procured table eggs from Milanino, Mericanel della Brianza and Valdarnese Bianca hens compared to two commercial hybrid strains\u2019 eggs to determine characterizing quality traits for traditional breeds conservation and valorization through high quality niche products. Fifty-four market eggs by three traditional breeds (Mericanel della Brianza\u2014MRC; Milanino\u2014MLN; and Valdarnese Bianca\u2014VLD) and two commercial hybrid strains (Commercial Hybrid Brown\u2014CHB; Commercial Hybrid White\u2014CHW) have been analyzed\u2014physical parameters, fatty acids profile and atherogenic and thrombogenic indexes were investigated. A General Linear Model\u2014GLM was applied to data analysis with breed and genetic origin (traditional breed\u2014TRD; commercial hybrid\u2014HYB) as sources of variation. Two Principal Component Analyses (PCA) were carried out with physical parameters and fatty acid parameters as variables. Eggs produced by traditional breeds MRC MLN and VLD differentiate from eggs produced by commercial hybrids CHB and CHW in physical and chemical parameters (fatty acids parameters). The nutritional value of the traditional eggs has been demonstrated to be higher considering the yolk content, the PUFA fraction, the more favorable n6/n3 ratio and the atherogenic and thrombogenic indexes. Commercial layers\u2019 eggs revealed their higher commercial value based on weight, albumen content and percentage of edible content