The effect of rearing system and length of fattening period on selected parameters of broiler carcass quality

This study involved analysis of some carcass quality parameters in broilers reared under two different non-industrial systems (extensive indoor and free range) at two different lengths of fattening period (56 and 63 days). The quality parameters tested included dressed carcass yield, dressing percentage, proportion of primal cuts (breast, drumstick, thigh, wing, pelvis and back) in dressed carcass, and proportion of major tissues (muscular tissue, bone and skin) in high-value carcass cuts (breast, drumstick and thigh). The objective of the study was to evaluate the effect of broiler rearing system, length of fattening period and gender on the carcass quality traits tested. The male broilers had a higher carcass weight at the slaughtering line at both lengths of fattening period, and the obtained differences were statistically significant. The broilers raised under extensive indoor system had a somewhat higher proportion of breast and a lower proportion of thigh and drumstick. A significant effect of gender was observed on these traits. The proportion of muscular tissue, bone and skin in the high-value primal cuts, including breast, drumsticks and thighs, dependent also on broiler gender and partly on the rearing system and length of fattening period

Uticaj proteaze dodate u hranu i pola na randman i konformaciju trupova tovnih pilića

This paper presents research results on the effect of protease on the dressing percentage of conventionally dressed carcass and body conformation in broiler chickens. Broiler diet was supplemented with 0.2% protease (group E-I) and 0.3% protease (group E-II), and protein content in the feed was reduced by 4% (E-I) and 6% (E-II) through a decrease in soybean meal content. Fast-growing Cobb 500 broilers were used for a 63-day fattening trial. Body conformation measurement included absolute carcass conformation measures (metatarsus length, keel length, breast depth, breast angle, thigh girth) and relative body conformation measures - conformation indices (body weight/metatarsus length, body weight/keel length, body weight/breast depth, body weight/thigh girth). Results showed a significant effect of sex on the dressing percentage of conventionally dressed carcass and all body conformation measures, whereas diet had a significant effect on the dressing percentage of conventionally dressed carcass and breast angle values.U radu su prikazani rezultati ispitivanja enzima proteaze na randman klasično obrađenog trupa i konformaciju trupova pilića u tovu. Enzim proteaza dodat je u hranu za piliće u tovu u koncentraciji 0,2% (O-I grupa), odnosno 0,3% (0-II grupa), uz istovremeno smanjivanje sadržaja ukupnih proteina u smešama za 4% (OI grupa), odnosno 6% (O-II grupa), preko smanjenog učešća sojine sačme. U ogledu je korišćen brzorastući hibrid Cobb 500, a tov pilića trajao je 63 dana. Za ocenu konformacije trupova utvrđene su apsolutne mere konformacije trupa (dužina piska, dužina kobilice, dubina grudi, grudni ugao, obim bataka) i relativne mere konformacije trupova - indeksi mera konformacije (telesna masa/dužina piska, telesna masa/dužina kobilice, telesna masa/dubina grudi, telesna masa/obim bataka). Rezultati istraživanja su pokazali da je pol pilića imao značajan uticaj na randman klasično obrađenog trupa i na sve mere konformacije trupova, a da je ishrana pilića različitim formulacijama obroka imala signifikantan efekat na randman klasično obrađenog trupa i vrednost grudnog ugla pilića

Uticaj nivoa proteina u hrani i dužine trajanja tova na randman i mere konformacije trupova pilića

This study analyses the effect of different protein levels in broiler feeds (supplemented with protease) and different lengths of fattening period on some parameters related to dressed carcass quality. Medium-growing Master Gris broiler chickens were used in a fattening trial lasting 63 days. At slaughter, dressing percentages and abdominal fat percentages were determined based on traditionally dressed carcass weights and abdominal fat weights of broilers at 49 and 63 days, and conformation indices were calculated based on absolute conformation measurements. Results showed that dietary treatment had an effect only on one relative conformation measurement - body weight/shank length in chickens at 49 days, as control broilers had higher values of this index compared to chickens receiving feeds containing reduced levels of crude protein and protease supplementation (0.2% or 0.3%). Length of fattening period affected almost all studied parameters, except breast angle, dressing percentage of traditionally dressed carcass and abdominal fat percentage.U radu je analiziran uticaj različitog nivoa proteina u hrani za tov pilića (uz dodatak enzima proteaze) i dužine trajanja tova na neke parametre kvaliteta obrađenih trupova. U ogledu je korišćen medium-growing linijski hibrid Master Gris, a ogled je trajao 63 dana. Na liniji klanja, na osnovu mase klasično obrađenog trupa i mase abdominalne masti pilića uzrasta 49. i 63.dana tova utvrđen je randman klasimično obrađenog trupa i udeo abdominalne masti, a na osnovu apsolutnih mera konformacije izračunati su indeksi mera konformacije. Rezultati ogleda su pokazali da je uticaj ispitivanih obroka ispoljio efekat samo na jednu relativnu meru konformacije trupova - telesna masa/dužina piska kod pilića starosti 49.dana, jer su pilići iz kontrolne grupe imali veću vrednost ovog indeksa u odnosu na piliće koji su hranjeni smešama sa nižim nivoima sirovih proteina, uz dodatak enzima proteaze (0,2% ili 0,3%). Različita dužina trajanja tova uticala je na skoro sve ispitivane parametre, izuzev na veličinu grudnog ugla, randman klasično obrađenog trupa i udeo abdominalne masti

Nutrition-related aspects of ascites in poultry

Pulmonary hypertension syndrome or ascites is a complex problem in poultry production. This disease has multiple causes, including genetic factors (genotype, sex) and non-genetic factors (altitude, improper egg incubation, ambient conditions in the poultry house, diet, etc.). Results from numerous studies have shown that improper diet and its interaction with other factors are among major reasons for the incidence of ascites symptoms. The objective of this study was to highlight major nutritional aspects related to pulmonary hypertension syndrome in broiler chickens. Therefore, particular attention should be paid to the dietary levels of antioxidant compounds, some minerals, energy and protein, feed forms, type of diet, and feed supplementation with ingredients which reduce the incidence of ascites

Hemijski sastav mesa kokoši nosilja iz alternativnih sistema gajenja

The aim of this paper was to estimate the effect of rearing systems (floor and organic) on the chemical composition of meat of laying hens. The tested genotypes were Isa Brown hybrid and dual purpose breed New Hampshire. Based on the results of this research can be concluded that the rearing system, generally, did not caused statistically significant differences in any of the parameters examined chemical composition of meat. On the other hand, the breast meat - white meat and thigh and drumstick - dark meat of New Hampshire genotype had significantly higher fat content compared to the Isa Brown hybrid. It must be noted that in the breast meat reported significant interaction genotype x rearing system. The other parameters of the chemical composition of meat were not significantly different between reared genotypes.Cilj ovog rada je bio da se ispita uticaj sistema gajenja na hemijski sastav mesa kokoši nosilja iz alternativnih sistema gajenja: podnog i organskog. Ispitivani genotipovi su bili linijski hibrid Isa Brown i rasa kombinovanih proizvodnih sposobnosti New Hampshire. Na osnovu rezultata ovih istraživanja može se zaključiti da sistem gajenja, generalno posmatrano, nije uzrokovao značajne razlike ni u jednom od ispitivanih parametara hemijskog sastava mesa. Sa druge strane, i meso grudi - belo meso i meso bataka i karabataka - tamno meso, New Hampshire genotipa je imalo značajno veći sadržaj masti u odnosu na Isa Brown hibrid, s tim što se mora napomenuti da se kod mesa grudi, javila i značajna interakcija sistem gajenja x genotip. Ostali ispitivani parametri hemijskog sastava mesa nisu se značajno razlikovali između ispitivanih genotipova

Efekti intenziteta svetlosti i gustine naseljenosti na telesnu masu i prinose vrednijih delova trupa brojlera

In order to determine the effect of intensity of light and stocking density, as well as the interaction of light intensity x stocking density on body weight and individual carcass traits, an experiment was performed on 1200 broilers of the Ross 308 genotype. The investigated factors were the intensity of light (LI): 20 lx (K) ; 150 lx (O) and stocking density (SD): 10 broilers/m2 (A); 13 broilers/m2 (B); 15 broilers/m2 (C), in 4 repetitions. The light source was incandescent bulbs of adequate intensity and a light program 16L: 4D: 2L: 2D was applied. Broiler body weight was controlled on 11th, 21st, 35th and 42nd day, by individual measurement of all chickens in the trial. The average sample containing 12 chickens per treatment with equal gender representation (total of 72 broilers) was used to study the slaughter quality of carcasses based on the parameters of absolute and relative yield of more valuable carcass parts (breast, thighs and drumsticks) and meat in the more valuable parts of the carcass. The effect of light with different intensity on the body weight differed depending on the broiler rearing phase. The interaction effect of the intensity of light and stocking density on the body weight of broilers was confirmed in all stages of growing up to the age of 42 days. A higher intensity of light (150 lx) showed the potential to alleviate the negative effects of higher stocking density (15 broilers/m2 ) on the final body weight of the broiler. The carcass traits were not significantly affected by the intensity of the light, while the stocking density, as well as the intensity of the light x stocking density did influence the yield of whole breast and the yield of breast meat.U cilju utvrđivanja efekta intenziteta svetlosti i gustine naseljenosti, kao i interakcije intenzitet svetlosti x gustina naseljenosti na telesnu masu i pojedine karakteristike trupa, sproveden je ogled na 1200 brojlera genotipa Ross 308. Ispitivani faktori su intenzitet svetlosti (LI): 20 lx (K); 150 lx (O) i gustina naseljenosti (SD): 10 grlo/m2 (A); 13 grlo/m2 (B); 15 grlo/m2 (C), u 4 ponavljanja. Izvor svetlosti su bile incandescent bulbs odgovarajućeg intenziteta i primenjen je svetlosni program 16L:4D:2L:2D. Telesna masa pilića je kontrolisana 11., 21., 35. i 42. dana, pojedinačnim merenjem svih pilića u ogledu. Na prosečnom uzorku od 12 pilića po tretmanu sa podjednakom zastupljenošću polova (ukupno 72 brojlera) izvršeno je ispitivanje klaničnog kvaliteta trupa na osnovu parametara apsolutnog i relativnog prinosa vrednijih delova trupa (grudi, bataci i karabataci) i mesa u vrednijim delovima trupa. Efekat svetlosti različitog intenziteta na telesnu masu se razlikovao u zavisnosti od faze gajenja brojlera. Interakcijski efekat intenziteta svetlosti i gustine naseljenosti na telesnu masu brojlera je potvrđen u svim fazama gajenja do starosti 42 dana. Veći intenzitet svetla (150 lx) je pokazao potencijal da ublaži negativne efekte većih gustina naseljenosti (15 grlo/m2 ) na završnu telesnu masu brojlera. Karakteristike trupa nisu bile pod značajnim glavnim efektom intenziteta svetlosti dok je gustina naseljenosti, kao i interakcija intenzitet svetlosti x gustina naseljenosti, uticala na prinos celih grudi i prinos mesa grudi

Uticaj enzima proteaze i dužine trajanja tova na randman klanja tovnih pilića

This study evaluates the effect of different crude protein levels in broiler diets supplemented with 0.2% and 0.3% protease enzyme (Ronozyme Pro Act) on dressed carcass weight and dressing percentage during two fattening periods (49 and 63 days). The fast-growing strain Cobb 500 was used. At the end of the fattening trial i.e. at 49 and 63 days, 10 male and 10 female birds were randomly sacrificed from each experimental group to determine body weights and conventionally dressed, ready-to-roast and ready-to-grill carcass weights. The data obtained were used to calculate the dressing percentages of the differently dressed carcasses. Results indicated that carcass weights and dressing percentages were not affected by diet (P>0.05), but also showed that the increase in the length of the fattening period by two weeks (from 7 to 9 weeks) led to increased carcass weights, while dressing percentages decreased (P (lt) 0.05).U radu su prikazani efekti različitih nivoa sirovih proteina u hrani za tovne piliće, uz dodatak enzima proteaze (Ronozyme Pro Act) u količini 0,2% i 0,3% na masu i randmane obrađenih trupova pri različitom trajanju tova (49 i 63 dana). U ogledu je korišćen brzorastući tovni hibrid Cobb 500. Na kraju oglednih perioda, 49 i 63. dana, odabrano je slučajnim izborom po 10 muških i 10 ženskih pilića iz svake eksperimentalne grupe i izmerena je masa grla pre klanja, masa klasično obrađenog trupa, trupa spremno za pečenje i trupa spremno za roštilj. Na osnovu ovih podataka izračunat je randman različito obrađenih trupova pilića. Dobijeni rezultati ukazuju da mase i randmani trupova nisu bili pod uticajem ispitivanih obroka (P>0,05), ali i da su se sa produžavanjem trajanja tova za 2 nedelje (sa 7. na 9 nedelja) povećale mase trupova, uz istovremeno smanjivanje randmana obrađenih trupova (P (lt) 0,05)

Efekat upotrebe sirove soje u završnim smešama za ishranu brojlerskih pilića na mere konformacije i udele vrednijih delova trupa

The experiment of the supstitution of soybean meal with raw soybean in the final diet was carried out on Hubbard F15 chickens at the age of 35-42 days. The effect of different levels and varieties of raw soybeans in diets on carcass conformation and share of major carcass parts was determined in a two factorial experiment 2 x 5 (2 soybean varieties x 5 levels of raw grains in the mixture), ie a total of 10 dietery treatments. At the end of the trial, by a random sample method, 12 chickens (6 males and 6 females) from each group were sacrificed and examined. The results showed that the index of drumstick girth and share of drumstick were under significant (p (lt) 0.05) influence of the soybean varieties. The level of raw soybeans in diets had significant effect (p (lt) 0.05) on the index of drumstick girth and on the absolute value of the breast depth and breast angle. Shares of breast and thighs of broiler chickens of both sexes were not significantly influenced by the studied factors. It was concluded that the share of raw soybean of 10, 15 and 20% in the final mixtures for broilers hinders the utilization of protein in the ration, resulting in poorer quality of chicken carcasses.Ogled je izveden na pilićima hibrida Hubbard F15 u uzrastu od 35-42. dana. Efekat upotrebe različitog nivoa sirove soje u smešama na konformaciju trupa i udeo vrednijih delova trupa utvrđen je dvofaktorijalnim eksperimentom 2 x 5 (2 sorte soje x 5 nivoa učešća sirovog zrna u smeši) sa 10 tretmana ishrane. Na kraju ogleda metodom slučajnog uzorka iz svake grupe žrtvovano je po 12 pilića (6 muških i 6 ženskih) u cilju utvrđivanja mera konformacije i udela vrednijih delova trupa. Dobijeni rezultati su pokazali da je indeks obima bataka bio pod značajnim (p (lt) 0,05) uticajem sorte soje. Nivo sirove soje u smešama imao je značajnog uticaja (p (lt) 0,05) na indeks obima bataka kao i na apsolutnu vrednost dubine grudi i grudnog ugla. Udeo bataka je bio pod značajnim (p (lt) 0,05) uticajem sorte soje. Udeli grudi i karabataka brojlerskih pilića oba pola nisu bili pod značajnim uticajem ispitivanih faktora. Zaključeno je da učešće sirove soje od 10, 15 i 20% u završnim smešama za ishranu brojlerskih pilića otežava iskorišćavanje proteinskog dela obroka. što rezultira slabijim kvalitetom pilećih trupova

Egg characteristics of New Hampshire laying hens from floor and organic rearing systems

The aim of this study was to compare the effect of two alternative rearing systems (floor and organic) on egg quality traits of New Hampshire laying hens in three different phases of the productive cycle (32, 48 and 72 weeks of age). Egg samples (15 eggs per group) were analysed for quality (egg weight, egg shape index, albumen height, Haugh unit, yolk colour) and chemical composition (dry matter, minerals, proteins and lipids). Egg weight, dry matter and protein content increased, while albumen height, Haugh unit and lipid content decreased with hen age (p≤0.05). Eggs from the floor rearing system had a higher shape index and lipid content compared to organic eggs (p≤0.05). Both factors and their interactions had a significant effect on yolk colour (p≤0.05)

Efekat proteaze na proizvodne i klanične osobine tovnih pilića

Carcass conformation is a very important parameter in assessing the overall appearance and meatiness of broilers. This study evaluates the effect of protease supplemented to reduced protein diets on production traits, dressed carcass weight and conformation measures in fast-growing Cobb 500 and slow-growing Master Gris broilers over a fattening period of 49 days. At slaughter, the following measurements were taken: pre-slaughter body weight (BW), conventionally dressed carcass weight and abdominal fat weight. Following carcass dissection into primal cuts, absolute conformation values, including metatarsus length (ML), keel length (KL), breast depth (BD), breast angle (BA) and thigh girth (TG), were determined. For carcass conformation evaluation purposes, index values of carcass conformation measures BW/ML, BW/KL, BW/BD and BW/TG were identified. Genotype and sex had a significant effect on dressed carcass weight and all conformation measures, whereas the effect of different protein levels in protease-supplemented diets was significant only in Master Gris, for metatarsus length and the following indices: BW/ML, BW/KL and BW/TG.Konformacija trupova pilića predstavlja vrlo važan parametar za ocenu opšteg izgleda i mesnatosti pilića. U radu je analiziran efekat enzima proteaze, uz snižen nivo sirovih proteina, na proizvodne osobine, masu obrađenog trupa i mere konformacije kod brzorastućeg-Cobb 500 i spororastućeg hibrida - Master Gris. Tov pilića trajao je 49 dana. Na liniji klanja izmerena je telesna masa pilića pre klanja, masa klasično-obrađenog trupa i masa abdominalne masti. Nakon rasecanja trupova na osnovne delove izmerene su apsolutne mere konformacije: dužina piska, dužina kobilice, dubina grudi, grudni ugao i obim bataka. Za bolju ocenu konformacije trupova izračunati su indeksi mera konformacije: telesna masa/dužina piska, telesna masa/dužina kobilice, telesna masa/dubina grudi i telesna masa/obim bataka. Značajan je bio uticaj genotipa i pola na masu obrađenih trupova i sve ispitivane mere konformacije, dok je uticaj različitih nivoa proteina, uz dodatak enzima proteaze, bio značajan samo kod hibrida Master Gris, i to za dužinu piska i indekse telesna masa/dužina piska, telesna masa/dužina kobilice i telesna masa/obim bataka