ISSN 1644-0714 e-ISSN 2300-6145

Zootechnica

Volume 10(3), 2011

Original Research Articles

The correlations between milk yield of goats and some milk nutrient content during a 3- and 5-month lactation and a full lactation 

Henryka Bernacka, Magdalena Mistrzak, Daria Kasperska

Abstract. A total of 203 White Improved goats from a farm in Rożnów (Kujawsko-Pomorskie province) were investigated in 2007–2009. The study attempted to simplify the current goat milk recording scheme and make it more accurate by shortening of the evaluation time and finding optimumlactationmonths for recording. In order to reach this aim, coefficients of phenotypic correlation were calculated using the multiple regression method between the yield and basic composition of milk over a 90- and/or 150-day lactation and the same traits for a full lactation taking into account the lactation number. The lactation length inWhite Improved goats varied according to the lactation from 228 days (1st lactation) to 303 days (3rd lactation), with the daily milk yield from1.90 kg to 2.60 kg. and the fat content of 3.10–3.30%and protein content of 2.80–2.90%. High and significant coefficients of phenotypic correlation between milk yield and composition over the 90- and 150-day lactation and the same traits over a whole lactation prove that every variant of the shortened recording may serve as a basis for the evaluation of goats before the lactation ends. Slightly higher coefficients of correlation (mostly above 0.900) found for the 5-month compared to the 3-month recording show that the evaluation encompassing four controlmilkings over a whole lactation ismore accurate. However, the 3-month recording during summer months is economically more beneficial. Shortening the frequency of control milkings followed by the reduction of costs will enable a greater number of goat herds to be recorded, which is of considerable importance to the efficiency of the breeding programme.

Evaluation of the growth and slaughter value of the Ross 308 broiler chickens 

Barbara Biesiada-Drzazga, Alina Janocha, Teresa Bombik, Anna Rojek, Urszula Brodzik

Abstract. The aim of this study was the evaluation of the growth of broiler chickens and their slaughter value from 1 to 42 days of age. The research material consisted of the Ross 308 chickens. At 42 days of rearing, the chickens reached the mean final body weight of 2229.9 g. During successive weeks of rearing, the weight of all elements, i.e. giblets, inedible parts and offal, increased with an increasing body weight of birds. At the same time, their percentage in the body weight decreased considerably, and the dressing percentage increased.At 42 days of rearing, the eviscerated carcass weight averaged 1697 g, the percentage of muscles was 46.7%, that of skin and fat was 11.0% and the remainders of the carcass (bones) accounted for 42.5%. During the rearing period, considerable changes in the tissue composition of carcass and their uneven growth were found. Moreover, the effect of age and type of muscle on the chemical composition of muscles was determined.

Genetic and production trends in New Hampshire laying hens over 8 generations 

Jolanta Calik

Abstract. The aim of the study was to determine trends for genetic and production parameters in a population of New Hampshire N-11 laying hens over 8 generations. Individual performance testing included body weight at 33 weeks of age (g), egg weight at 30 weeks of age (g), age at puberty expressed as days of age at first egg (days), and number of eggs laid to 39 weeks of age. As a result of implementing the genetic improvement programme based on NOVASEL electronic data processing system, egg production was increased, age at first egg was advanced and body weight of the chickens decreased in the N-11 line. The analysis of estimates of effective population size (Ne) and coefficients of inbreeding (Fx) shows that the cockerel and hen mating system used for reproduction effectively protects the population from an increase in inbreeding.

Comparison of meat performance of fattening bulls and culled cows of Montbeliarde and Polish Holstein-Friesian breeds and their influence on income value from their sale 

Marcin Gołębiewski, Piotr Brzozowski

Abstract. The aim of the researches was to compare meat performance of fattening bulls and culled cows of Montbeliarde and Polish Holstein-Friesian breeds as well as to estimate their influence on income value. In the researches 97 bulls and 68 cows were taken under consideration. Data consisted of: breed, age, live weight, carcass weight and EUROP classification. For calculating income value of cows and fattening bulls market prices from 2010 year were used. Significant influence of the breed on live weight as well as carcass weight were reported. Cow and bulls of montbeliarde breed characterized by heavier live body weight, better dressing rate as well as much better results of EUROP classification. Therefore, average value of cow and bulls of montbeliarde breed was significantly higher if compared to Polish Holstein-Friesian.

Effect of age and sex on body weight and body dimensions of pearl grey guinea fowl (Numida meleagris L.) 

Daria Kasperska, Henryka Korytkowska, Dariusz Kokoszyński

Abstract. Sixty pearl grey guinea fowl were investigated. Birds were kept in a closed facility without regard to sex. For the first three weeks, guinea fowl were kept in boxes on plastic mesh floor, and then in straw-bedded pens. They were fed commercial mash diets for turkeys or hens. At the end of 13 and 52 weeks of age, body weight was determined and birds selected for slaughter were subjected to body measurements.As guinea fowl aged, their body weight and body dimensions increased except for lower leg length in males. Compared to 13-week-old males, males aged 52 weeks had significantly higher body weight and highly significantly higher sternum length and chest circumference. As females aged, their body weight, lower leg length and chest circumference increased highly significantly, and sternum length and shank length increased significantly. Males compared to females were characterized by lower body weight at both evaluation times, and by significantly shorter lower leg at 52 weeks of age. The body conformation indices of massiveness, compactness and long-leggedness were higher in older birds.

Effect of season on plasma concentration of insulin-like growth factor-I and 1.25-dihydroxycholecalciferol in horses  

Jarosław Łuszczyński, Magdalena Pieszka

Abstract. During the summer season, plasma concentrations of insulin-like growth factor I (IGF-I) inArabian,Anglo-Arabian and Hucul horses as well as colts and fillies were higher compared to the winter season. Significant differences in IGF-I concentration between the seasons were found in Hucul horses (P≤0.01) and in colts (P≤0.05). Season had no significant effect on 1.25(OH)2-D3 concentration in the horse breeds studied. However, plasma concentrations of this hormone were always higher in the summer than in the winter season regardless of the breed (exceptAnglo-Arabians) and sex. Knowledge and monitoring of the physiological concentrations of IGF-1 and vitamin D3 metabolites in different seasons of the year, combined with analysis of growth rate during these periods may contribute to the improvement of the horse management and feeding system. Because of the association between these hormones and the frequency of developmental orthopaedic diseases, this information could be potentially used in veterinary practice.

The effect of dairy cattle management systems on milk yield, composition and somatic cell count 

JanMiciński, Janina Pogorzelska

Abstract. The study was conducted on two family farms (herdsAand B). The experimental materials comprised Polish Holstein-Friesian cattle raised in 2006–2009. The objective of this study was to compare SCC, the yield and composition of milk from Holstein-Friesian Black-and-White cows kept in the tie-stall and free-stall system for four years. The analysis indicates that cows housed in a tie-stall barn (herdA) were characterized by higher milk performance than cows kept in a freestall barn (herd B).Milk yield was correlated with SCC in milk in both herds.Yield increase in the Aherd was connected with the SCC decrease. Such dependence has not been found in the herd B.

The influence of the season of the birth of Duroc and Pietrain boars and their crossbreeds on sperm traits 

Kazimierz Pokrywka, Krzysztof Tereszkiewicz

Abstract. The aim of this study was evaluation of the quality of ejaculates of boars from Duroc and Pietrain breeds, and also crossbreeds born in different seasons. Materials used for the study were gathered during the process of breeding boars. There were 143 boars of breeds Duroc, Pietrain and their crossbreeds (Duroc x Pietrain and Pietrain x Duroc). The 20 442 of boars’ ejaculates were examined between 1997–2009 in the Małopolska Biotechnology Centre – Examinations Station of Boars in Czermin. Ejaculates were evaluated basing on: the volume of spermatozoid fractions, the percentage of progressive spermatozoids, spermatozoid concentration, total count of progressive spermatozoids and the total number of insemination doses obtained from one ejaculation. The parameters of examined ejaculates of boars races were analyzed statistically accordingly with their births seasons: spring (from 22nd March to 21st June), summer (from 22nd June to 21st of September), autumn (from 22nd September to 21st of December), winter (from 22nd December to 21st of March). The studies have shown the significance of impact that season of birth has on semen quality of boars and crossbreeds of evaluated races. The highest reproductive potential expressed as a number of insemination doses, was found in boars of Duroc and Pietrain breeds born in the summer. In case of crossbreeds, the best quality of sperm was found in males born in the winter season.

The effect of dry period length on the course of milk production of Polish Holstein-Friesian var. Black-and-White cows 

Ewa Salamończyk, PiotrGuliński

Abstract. Based on the results of milk performance of lactating cows, 15 659 Black-and-White with varied addition of HF genes was evaluated in the course of lactation milk production depending on the length of the dry period before the full lactations investigated. Breast plotted curves according to selected groups of animalsWood’s model. The average milk yield of ECM, the study population was: 6 573 kg of standard lactation and 7 063 kg in the lactation lasted an average of a full 352 days. It also showed that these cows, calving over the years 1995–2008 were marked by very high persistence of lactation. The average monthly decline in milk production after peak lactation was 3.52% (LPI = 31.7%). Of the four genetic groups rated highest in the persistence of lactation (the lowest rate of LPI) had a cow with the shortest period of the dry, less than 45 days in three groups of genes, Black-and-White animals which, in its genotype from 50.1 to 75% HF, from 75.1 HF to 99.9% and cows Polish Holstein-Friesian (100%).Monthly average daily milk yield decrease in ECM from 1 month of lactation, for these groups of animals ranged from 1.9% to 3.4%.

The effect of bacterial silage inoculant on the fermentation, cell wall contents and aerobic stability of maize silage 

Marek Selwet

Abstract. This research was carried out to determine the effects of bacterial silage inoculant using as silage additives on the fermentation charakteristics, cell wall contents and aerobic stability of maize silages. Maize silage was harvested in the 89 (BBCH) developmental ripening stage. Biological additive was used as additive which contains Enterococcus faecium PCM 1858, Pediococcus acidilactici PAL-34, Lactobacillus plantarum PCM 493, Lactobacillus buchneri DSMZ 5987, Lactobacillus rhamnosus PCM 489, Lactobacillus brevis PCM 488, Lactobacillus lactis PCM 2379. Maize was ensiled in 4 dm3 special PCV laboratory microsilos with a cover permitting gaseous products. The microsilos were stored at 10–15±2ºC undr laboratory conditions. Microsilos from each group were sampled for microbiological and chemical analyses on the days 3, 14, 21 and 60 after ensiling, whereas aerobic stability was determined after 7 days. As a result, bacterial silage inoculant improved fermentation, decreased cell wall contents, deoxynivalenol (DON) concenration, do not improved aerobic stability of maize silage after 7 days exposure to air.

Effect of the quality of handling and care on the reproduction parameters of mink 

Beata Seremak, Małgorzata Dziadosz, Bogdan Lasota, Lidia Felska-Błaszczyk, Kamil Pławski, Anna Masłowska, Grzegorz Mieleńczuk

Abstract. The aim of this study was to determine the effect of animal handling, defined as the so-called human factor, on the level of reproductive parameters of female mink.We analyzed some reproductive parameters of 6 348 one- and two-year-old Scanbrown females, such as fertility, prolificacy and rate of rearing the young. Mink were divided into four groups; group I and II consisted of one-year-old females, group III and IV comprised females at age two years. Individual groups of females were operated by four different teams of workers. The results indicate a strong influence of the quality of care on the parameters of breeding.

The influence of the breed and age on the libido of insemination boars 

Bogdan Szostak, Joanna Sarzyńska

Abstract. The libido of a boar is a very important factor which determines the male’s suitability for insemination. Before a breeder is included in the semen production cycle, its libido has to be estimated, which may significantly contribute to the improvement of the organization of work in breeding stations.Many factors influence a boar’s libido.Among others, it is the male’s age and breed. In this work the influence of the breed and age on the sexual behaviour of boars is estimated, as well as the phenotype correlations between a boar’s libido and the parameters of the semen are defined. It has been proved that among the analysed breeds and hybrids the highest libido characterized PIC hybrids, and hybrids such as: Pietrain x Duroc and Duroc x Pietrain, and among the pure breed boars – Duroc breed. It has also been proved that the sexual activity of boars decreases with age. Significant correlations between a boar’s libido and some features of the semen have been shown.