Zenon Bernacki

Effect of age and sex on slaughter value of guinea fowl (Numida meleagris).

The effects of age and sex of guinea fowl on their dressing percentage, carcass composition, pH value, water holding capacity, colour and sensory properties of meat was determined. At 16 weeks of age, males and females had significantly higher body weights and carcass weights compared to birds at 13 weeks of age. The carcasses of older birds contained more breast muscles, leg muscles and skin with subcutaneous fat, and less wings, with a significant difference for males. At both evaluation times, males compared to females had lower body weight, carcass weight, dressing percentage, content of breast muscles and abdominal fat, and a higher proportion of leg muscles. Older birds had significantly lower redness (a*) values for breast muscles in males and for leg muscles in females.

COMPARISON OF MEAT PERFORMANCE OF PEKIN DUCKS FROM TWO CONSERVATIVE FLOCKS

Pekin ducks from P44 and P55 conservative flocks were compared for body weight and dimensions, feed intake, dressing percentage and carcass composition. P44 ducks, compared to P55 birds, had greater body weight (3124 vs. 3051 g), longer trunk with neck (47.8 vs. 47.5 cm), trunk (25.8 vs. 25.3 cm), keel (13.3 vs. 12.8 cm) and shanks (6.3 vs. 6.2 cm) as well as significantly greater chest circumference (34.6 vs. 33.7 cm). P55 ducks were characterized by lower feed intake per bird (7.48 kg) and per kg body weight (2.45 kg) and greater European Production Index (259 points) compared to P44 ducks (7.73 kg, 2.53 kg, 251 points). The carcasses of P44 ducks contained more breast muscles (12.6%) and skin with subcutaneous fat (31.4%) but less leg muscles (13.2%) compared to P55 birds (12.3, 29.7 and 13.9% of carcass with neck, respectively).

CARCASS COMPOSITION AND PHYSICOCHEMICAL AND SENSORY PROPERTIES OF MEAT FROM BROILER CHICKENS OF DIFFERENT ORIGIN

Three commercial lines of broiler chickens, Ross 308, Hubbard Flex and Hubbard F15 were investigated. Preslaughter weight, weight of eviscerated carcass with neck and dressing percentage were the highest in Hubbard Flex and the lowest in Ross 308 chickens. Analysis of carcass composition showed statistically significant differences in the content of neck, wings, breast muscles, skin with subcutaneous fat, abdominal fat and remainders of the carcass. The highest muscle content (total proportion of breast and leg muscles in carcass) was found in Hubbard Flex chickens, and the lowest body fat content (total proportion of skin with subcutaneous fat and abdominal fat) in Ross 308 birds. Chicken origin had a significant effect on pH15, water holding capacity, colour lightness (L*), yellowness (b*) and aroma and juiciness of breast muscles.

CARCASS COMPOSITION AND MEAT QUALITY OF GREY PARTRIDGE (PERDIX PERDIX L.)

The aim of the study was to determine the body weight, dressing percentage, carcass composition and physico-chemical and sensory properties of meat from grey partridge (Perdix perdix L.). At the age of 32 weeks, male and female grey partridge had similar body weight (301.4 g vs 299.5 g), carcass weight (218.2 g vs 216.0 g) and dressing percentage (72.4% vs 72.1%). Dissection analysis showed non- significant differences in carcass composition between males and females. The carcasses of males contained more leg muscles (17.4%), skin with subcutaneous fat (5.5%) and neck (3.4%), but less breast muscles (30.7%) and wings (8.8%) compared to the carcasses of females (17.0%, 5.3%, 3.3%, 31.1% and 10.7%, respectively). Compared to males, the breast muscles of females were characterized by significantly higher water holding capacity. In addition, females showed significantly (P 0.05) lower values of lightness (L*), yellowness (b*) and tenderness of breast muscles compared to males.

Body Conformation and Internal Organs Characteristics of Different Commercial Broiler Lines

I Professor, Department of Poultry Breeding, Faculty of Animal Breeding and Biology UTP University of Science and Technology, Bydgoszcz, Poland II Master of Science, Sohag University, Faculty of Agriculture, Department of Poultry and Animal Breeding, Sohag, Egypt III Master of Science, Department of Poultry Breeding, Faculty of Animal Breeding and Biology UTP University of Science and Technology, Bydgoszcz, Poland

The effect of corn or beet pulp silage supplemented diet on production parameters, oxidative stability of muscles and fatty acid composition of abdominal fat in geese

Abstract The aim of this study was to assess the production parameters of White Koluda® geese fed with a corn or beet pulp silage supplemented diet. The oxidative stability of breast and thigh muscles during frozen storage and the fatty acid composition of abdominal fat were also investigated. Measurements were carried out on a total of 42 geese of the White Koluda® W31 strain that were divided into three experimental groups: group I (control) - basal diet, group II - basal diet with corn silage addition, group III - basal diet with pressed beet pulp silage addition. Diets containing ad libitum maize silage or sugar beet pulp silage supplemented with a limited amount of commercial diets, significantly reduced BW (about 9%) and ADG (about 27%) of birds compared to the control group in the 14th week of rearing. Feeding corn or sugar beet pulp silage to geese did not affect pH values, heme iron content, colour parameters but decreased lipid oxidation values in muscles 3 days after slaughter. The abdominal fat of geese fed with the pressed beet pulp silage supplemented diet was characterized by a significantly higher content of myristic and linoleic acid and a lower content of oleic acid. In conclusion, feeding geese with limited amount of commercial mixtures supplemented with maize or sugar beet pulp silages may be recommended primarily for increasing financial efficiency in White Koluda® geese farms but also for improving the quality of goose carcasses, due to their low fat and high quality of meat.

Evaluation of genetic similarity between white and grey varieties of guinea fowl (Numida meleagris).

The aim of the study was to determine DNA polymorphism between and within white and grey varieties of guinea fowl. At the end of 12 weeks of age, blood was sampled from 13 white and 16 grey guinea fowl, and DNA was isolated. Genetic similarity between the birds was evaluated using RAPD-PCR technique. PCR with five primers was performed in birds studied. The largest number of bands appeared after electrophoresis with AB1-05 and AB1-09 primers, and the smallest number when AB1-08 primer was used. Genetic similarity between the white and grey varieties of guinea fowl, determined as the mean for the primers used, was 0.97. The coefficient of genetic similarity averaged 0.65 within white variety and 0.64 within grey variety.

Body Morphometry and Development of the Digestive System of Grey Partridge (Perdix Perdix) Depending on Age and Gender

I Professor, Department of Poultry Breeding, Faculty of Animal Breeding and Biology, UTP University of Science and Technology, Bydgoszcz, Poland II Doctor of Philosophy, Department of Poultry Breeding, Faculty of Animal Breeding and Biology, UTP University of Science and Technology, Bydgoszcz, Poland III Master of Science, Department of Poultry and Animal Production, Faculty of Agriculture, Sohag University, Sohag, Egypt IV Master of Science, Department of Poultry Breeding, Faculty of Animal Breeding and Biology, UTP University of Science and Technology, Bydgoszcz, Poland V Master of Science, Division of Animal Product Evaluation, Faculty of Animal Breeding and Biology, UTP University of Science and Technology, Bydgoszcz, Poland

Carcass composition and quality of meat from Pekin ducks finished on diets with varying levels of whole wheat grain

The aim of the research was to determine the effect of replacing part of a commercial feed mixture with whole wheat grain on the bodyweight, carcass composition and meat quality of Pekin ducks. A total of 160 1-day-old sexed SM3 Heavy hybrid ducks were used in the study. Two diets were given during the rearing period (36–49 days): (1) a complete commercial diet ad libitum, and (2) restricted amounts of a commercial diet (85%) and whole wheat grain (15%). Each treatment consisted of four replications of 20 birds each. Adding whole wheat grain to the ration resulted in no significant (P > 0.05) changes in bodyweight (3475.8 g), feed conversion ratio (0–49 days, 2.50 kg DM intake/kg liveweight gain) dressing percentage (70.1%) and carcass tissue composition in ducks at 49 days of age. Breast muscle (superficial pectoral muscle) from ducks fed the commercial diet and whole wheat grain was significantly (P < 0.05) lighter in colour (L* = 39.9 vs 38.0) and a deeper yellow colour (b* = 1.7 vs 0.8), as compared with that from birds receiving the complete commercial diet alone. Breast muscle (superficial pectoral muscle and profound pectoral muscle) also had significantly (P < 0.05) higher threonine (3.9 vs 5.1 g/100 g DM) and valine content (4.0 vs 5.0 g/100 g DM). However, leg muscle (thigh and drumstick muscles) from experimental ducks had a significantly (P < 0.05) lower content of crude fat (5.1% vs 4.2%) and collagen (1.5% vs. 1.1%), as well as less glutamic acid (14.2 vs 12.5), proline (3.5 vs 3.2), alanine (3.0 vs 2.5) and arginine (6.5 vs 5.6 g/100 g DM), as compared with the control birds.

Polymorphism of prolactin gene and its association with growth and some biometrical traits in ducks

Abstract The main aim of the study was to estimate the polymorphism of prolactin (PRL) gene and its relation with some morphological traits (body weight – BW, length of trunk with neck – LTN, length of trunk – LT, chest girth – CG, length of breast bone – LBB, length of shank – LS) of Muscovy, Pekin and Mulard ducks. A secondary objective of this study was to evaluate the effect of age, origin on ducks’ growth performances. Three genotypes at locus PRL/XbaI and one genotype at locus PRL/PstI were found. The results showed that Pekin ducks with the PRL/TT genotype in selected terms of evaluation characterised by higher (p < 0.05) LS and LBB values than those with the PRL/TG genotype. In Mulard ducks, PRL/XbaI polymorphism had an effect (p < 0.05) on BW and LS in birds aged 10 and 12 weeks (wk). The effect of age, origin on the growth traits of ducks was evaluated as well. All growth traits examined significantly increased with age. There was a significant (p < 0.01) effect of the ducks’ origin. Until the 7 wk of age, the Muscovies were lighter and had lower (p < 0.01) values of LTN, LT, CG, LBB, LS than Pekin and Mulard ducks. The results confirm that there were significant associations between interaction of considered factors and estimated traits.