Efficiency of Utilizing Bulls with High Immune Response (HIR) in Terms of Reproductive Traits of PHF Cows.

Reproductive traits in dairy cattle are crucial for herd productivity and profitability. This study investigates the influence of relatedness to high immune response (HIR) Immunity+ sires on reproductive performance indicators in Polish Holstein-Friesian cows. A total of 5094 cows were analyzed, categorized based on their relatedness to HIR Immunity+ sires, and assessed for various reproductive parameters, including age at first insemination, gestation length, days open, calving interval, and calving ease. The results showed that the level of relatedness to HIR Immunity+ sires influenced certain reproductive traits, such as service period, gestation length, and age at first and second calving. Additionally, cows related to HIR Immunity+ sires exhibited a higher frequency of twin pregnancies and more complicated births. While some benefits were observed in certain reproductive traits among cows related to HIR Immunity+ sires, such as reduced age at first insemination and shortened gestation length, the overall impact on reproductive efficiency remains inconclusive. Further studies are needed to fully elucidate the effects of using semen from HIR Immunity+ sires on reproductive performance in dairy cattle.

Clinical applicability of external and internal body dimensions in predicting dystocia in late-gestation Holstein-Friesian heifers.

The objective of this study was to determine the clinical applicability of maternal intrapelvic area (PA) and selected morphometric parameters that can be measured before parturition in predicting dystocia in dairy heifers. The measurements were performed in 374 late-gestation Holstein-Friesian heifers. Inner pelvic height and width were measured using a pelvimeter, and PA was calculated. The heifers were monitored continuously around the time of calving, and calving difficulty was categorized as: unassisted calving (UC), slight assistance (SA), considerable difficulty (CD) and veterinary assistance (VA). Calving performance was analysed with the χ2 test, and the effect of body dimensions on the course of parturition was evaluated by one-way analysis of variance. Dystocia (CD + VA) was predicted with the use of the classification tree method. Dystocia accounted for 29.14% of all deliveries. The percentages of stillbirths and retained placenta increased (p < .01) with increasing calving difficulty. Average PA immediately before parturition was smaller (p < .01) in group VA (223.2 cm2 ) than in group UC (253.3 cm2 ). According to the classification tree, dystocia may occur (74.07% odds) in heifers with PA < 254.2 cm2 and a rump angle <5.68° before parturition. Measurements of heifer's cannon circumference and sire's body size improve the accuracy of dystocia prediction.

Multi-Trait Single-Step Genomic Prediction for Milk Yield and Milk Components for Polish Holstein Population.

The objective of our study was to evaluate the predictive ability of a multi-trait genomic prediction model that accounts for interactions between marker effects to estimate heritability and genetic correlations of traits including 305-day milk yield, milk fat percentage, milk protein percentage, milk lactose percentage, and milk dry matter percentage in the Polish Holstein Friesian cow population. For this aim, 14,742 SNP genotype records for 586 Polish Holstein Friesian dairy cows from Poland were used. Single-Trait-ssGBLUP (ST) and Multi-Trait-ssGBLUP (MT) methods were used for estimation. We examined 305-day milk yield (MY, kg), milk fat percentage (MF, %), milk protein percentage (MP, %), milk lactose percentage (ML, %), and milk dry matter percentage (MDM, %). The results showed that the highest marker effect rank correlation was found between milk fat percentage and milk dry matter. The weakest marker effect rank correlation was found between ML and all other traits. Obtained accuracies of this study were between 0.770 and 0.882, and 0.773 and 0.876 for MT and ST, respectively, which were acceptable values. All estimated bias values were positive, which is proof of underestimation. The highest heritability value was obtained for MP (0.3029) and the lowest heritability value was calculated for ML (0.2171). Estimated heritability values were low for milk yield and milk composition as expected. The strongest genetic correlation was estimated between MDM and MF (0.4990) and the weakest genetic correlation was estimated between MY and ML (0.001). The genetic relations with milk yield were negative and can be ignored as they were not significant. In conclusion, multi-trait genomic prediction can be more beneficial than single-trait genomic prediction.

Estimation of Body Weight Based on Biometric Measurements by Using Random Forest Regression, Support Vector Regression and CART Algorithms.

The study's main goal was to compare several data mining and machine learning algorithms to estimate body weight based on body measurements at a different share of Polish Merino in the genotype of crossbreds (share of Suffolk and Polish Merino genotypes). The study estimated the capabilities of CART, support vector regression and random forest regression algorithms. To compare the estimation performances of the evaluated algorithms and determine the best model for estimating body weight, various body measurements and sex and birth type characteristics were assessed. Data from 344 sheep were used to estimate the body weights. The root means square error, standard deviation ratio, Pearson's correlation coefficient, mean absolute percentage error, coefficient of determination and Akaike's information criterion were used to assess the algorithms. A random forest regression algorithm may help breeders obtain a unique Polish Merino Suffolk cross population that would increase meat production.

Use of Multivariate Adaptive Regression Splines Algorithm to Predict Body Weight from Body Measurements of Anatolian buffaloes in Türkiye.

Anatolian buffalo is an important breed reared for meat and milk in various regions of Türkiye. The present study was performed to estimate body weight (BW) from several body measurements, such as tail length (TL), shoulder height (SH), withers height (WH), body length (BL), chest circumference (CC), shank diameter (SD) and birth weight (BiW). The data set was taken from Mus Province of Türkiye. In this respect, 171 Anatolian buffaloes were used. To estimate the BW, different proportions of the training and test sets were used with the MARS algorithm. The optimal MARS was determined at a proportion of 70-30%. The MARS model displays the heaviest BW that can be produced by Anatolian buffalo according to tail length, body length, chest circumference and shoulder height. In conclusion, it could be suggested that the MARS algorithm may allow animal breeders to obtain an elite population and to determine the body measurements affecting BW as indirect selection criteria for describing the breed description of Anatolian buffalo and aiding sustainable meat production and rural development in Türkiye.

Comparison of Random Regression Models with Different Order Legendre Polynomials for Genetic Parameter Estimation on Race Completion Speed of Arabian Horses.

This work aimed to compare the fitting performance of the random regression models applied to the different order orthogonal Legendre polynomials on the race completion speed (m/s) of Arabian racing horses. Legendre polynomial function for additive genetic, permanent environmental variances and heritability values with the L(2,2), L(2,3), L(3,2) and L(3,3) models (where L(i,j) means L(order of fit for additive genetic effects, order of fit for permanent environmental effects)) was estimated. A total of 233,491 race speed records (m/s) of Arabian horses were taken from the Jockey Club of Turkey between 2005 and 2016. The mean and standard deviation of heritability values were estimated as 0.294 ± 0.0746, 0.285 ± 0.0620, 0.302 ± 0.0767 and 0.290 ± 0.1018 for L(2,2), L(2,3), L(3,2), and L(3,3), respectively. The steady decreasing trend of permanent environmental variances for L(2,2) provided stationery for heritability values. According to Akaike information criterion (AIC) and Bayesian information criterion (BIC) values, the L(2,2) model could be reliably used to estimate heritability values for the racing speed of Arabian horses in the presence of repeated observations.

Farmers' Risk Perception on Climate Change: Transhumance vs. Semi-Intensive Sheep Production Systems in Türkiye.

Sheep farmers' perceptions of climate change and its impacts and the adaptation strategies they consider to address these risks are of great importance in ensuring the resilience of farming practice. This study focused on sheep farmers' perception of climate change and the risks and actions taken to mitigate these impacts. A total of 68 surveys were carried out among sheep farmers (39 transhumance and 29 semi-intensive farmers) by two different representative production systems in Türkiye. Variables regarding the socio-economic profile, climate change impacts, and adaptation strategies were identified and analyzed. Principal component analysis and a Pearson Chi-square test were used to evaluate the data. Both farmers' groups accepted and perceived climate change, showing good awareness and perception. The farmers' attitudes towards adaptation to climate change were associated with production systems. Transhumance farmers had limited adaptation and coping strategies compared to semi-intensive farmers. Transhumance farmers focused mainly on selling livestock (mostly to cope with degraded natural grassland/feed deficiency) as an adaptive strategy. In contrast, semi-intensive farmers focused on modifying their farm management and feed operations, such as changing the feed ratio and supplement use, improving water and feed storage, and considering crop feed production. The knowledge obtained from this study could be helpful for farmers and policymakers who develop long-term small ruminant production strategies that consider the effects of climate change and adapt them to different farming systems in the Türkiye.

Genetic Parameters for Methane Emissions Using Indirect Prediction of Methane and Its Association with Milk and Milk Composition Traits.

The study covers milk yield and composition data for 17,468 Polish Holstein-Friesian cows. Methane production (g/lactation per cow, MP) for dairy cow were predicted using three methane production equations (MPE) that took into account: milk yield (MPE1), energy corrected milk (MPE2) and both milk protein concentration (%), and energy-corrected milk (MPE3). The average amounts of methane produced for each cow per lactation were 31,089 g, 46,487 g, and 51,768 g for MPE1, MPE2, and MPE3, respectively. Repeatability models were used to estimate genetic parameters for MP. The estimated heritabilities for MPE1, MPE2, and MPE3 were 0.30, 0.24, and 0.24, respectively, with a standard error of 0.01. High genetic correlations (>0.76) were obtained between methane and milk yield, protein, fat, lactose and dry matter contents in milk for MPE1, MPE2 and MPE3. Still, a moderate genetic correlation (0.34) was obtained between methane and fat content (MPE1); the standard error of the estimated genetic correlation was less than 0.05. The results of the current study indicate that genetic selection aimed to reduce MP in dairy cows is possible. However, such direct genetic selection could cause a negative genetic response in milk yield and composition due to negative genetic correlations between MP and milk yield and composition.

Carcass Characteristics, Digestive System Traits of Spent Broiler Breeder and Dual-Purpose Hens.

Raising dual-purpose hens for meat is believed to bring more economic benefits to farmers selling products directly to consumers. The aim of the study was to determine the differences between the carcass features and the digestive system of multipurpose hens and spent broiler breeders. In the experiment, 20 carcasses of 70-week-old Rosa 1 dual-purpose hens and 20 carcasses of 62-week-old Ross 308 broiler breeders were used. Measurements of the length of various sections of the intestine and the diameter of individual intestinal segments were made. During the gutting, proventriculus, gizzard, liver, heart, and spleen were separated and then weighed. Dual-purpose hens differed significantly (p < 0.05) from broiler breeders in weight and carcass dimensions. Multipurpose hens were characterized by significantly lower (p < 0.05) percentages of breast muscles, leg muscles, skin with subcutaneous fat, wings, and carcass remainders. Broiler breeders were characterized by significantly longer (p > 0.05) total intestinal length, duodenum, jejunum, ileum, and terminal intestine. Significant differences were confirmed in terms of the diameter of some segments of the intestine. Broiler breeder hens also had a greater mass of internal organs compared to the dual-purpose layer hens.

Forecasting Milking Efficiency of Dairy Cows Milked in an Automatic Milking System Using the Decision Tree Technique.

In barns equipped with an automatic milking system, the profitability of production depends primarily on the milking efficiency of a cow (ME; kg/min) defined as cow milk yield per minute of box time. This study was carried out on 1823 Polish Holstein−Friesian cows milked by the automatic milking system (AMS) in 20 herds. Selected milking parameters recorded by the AMS were analyzed in the research. The aim of the study was to forecast ME using two statistical techniques (analysis of variance and decision trees). The results of the analysis of variance showed that the average ME was 1.67 kg/min. ME was associated with: year of AMS operation (being the highest in the first year), number of cows per robot (the highest in robots with 61−75 cows), lactation number (highest for multiparas), season of calving (the highest in spring), age at first calving (>36 months), days in milk (151−250 days) and finally, rear quarter to total milk yield ratio (the highest between 51% and 55%). The decision tree predicted that the highest ME (2.01 kg/min) corresponded with cows that produced more than 45 kg of milk per day, were milked less than four times/day, had a short teatcup attachment time (<7.65 s) and were milked in robots that had an occupancy lower than 56 cows.

Carcass characteristics and selected meat quality traits from commercial broiler chickens of different origin.

The aim of the study was to compare carcass and meat quality traits in 42-day-old Ross 308 and Cobb 500 broiler chickens. Forty carcasses were studied. Acidity (pH24 ) and electrical conductivity (EC24 ) of pectoralis major muscle and drumstick were determined 24 h postmortem. After carcass cutting, samples of breast and leg meat were collected for determination of quality traits. Broiler genotype had a significant effect on abdominal fat content in carcass and on water, protein, fat, sodium, and magnesium content in breast meat. Bird origin had an effect on the lightness, yellowness, horizontal diameter of muscle fiber, horizontal:vertical (H:V) diameter ratio, and most textural characteristics of pectoralis major muscle, as well as on the pH (pH24 ), electrical conductivity (EC24 ), and yellowness (b*) of leg muscles. Sex of birds had a significant effect on carcass weight, water, fat and collagen content, L*, a*, b* color attributes, and chewiness and gumminess of breast meat and on water and protein content in leg muscles. The present study provided information on the differences in carcass and meat quality between Ross 308 and Cobb 500 broiler chickens.

Growth and Slaughter Characteristics of Weaning Male Kids of Turkish Native Goat Breeds.

There is little knowledge about the carcass potential of Turkish native goat breeds raised under different rearing conditions. It is necessary to compare the carcass characteristics of these breeds to minimize the effect of the rearing conditions. Therefore, this study aims to compare the growth, slaughter, and carcass characteristics of male kids at weaning age to eliminate the impact of rearing conditions. Kids born to Angora (n = 6), Hair (n = 6), Honamli (n = 6), and Kilis (n = 6) Turkish native goat breeds, ranging in age from 2-3 years, were slaughtered at 90 days of weaning age and carcass characteristics were determined immediately. There were differences (p < 0.05) among breeds in terms of birth weight (BW) and daily weight gain (DWG) from birth to weaning age. Honamli kids had higher BW and DWG than those of other breeds (p < 0.05). Similarly, carcass weights (hot-cold) and yields (hot-cold) of Honamli kids were higher compared to kids born to other breeds (p < 0.05). Additionally, Honamli and Hair kids had higher longissimus-dorsi (LD), and semitendinosus (ST) muscle weights compared to Kilis and Angora kids. Interestingly, Kilis kids had lower BW and DWG than those of other breeds (p < 0.05). There were significant differences (p < 0.05) among breeds in terms of non-carcass parts and organ weights. Positive correlations were calculated between cross-sectional area and weight (r = 0.793; p < 0.01), length and weight (r = 0.723; p < 0.01), and depth and weight (r = 0.698; p < 0.01) in LD muscle of all kids. A similar correlation trend was calculated for the ST muscle (cross-sectional area and weight; r = 0.699; p < 0.01, length and weight; r = 0.751; p < 0.01, and depth and weight; r = 0.528; p < 0.05) in all kids. In conclusion, the present study results showed that Honamli kids could be used for fattening material due to their good carcass quality compared to other native breeds.

Genetic Parameters Estimation of Milking Traits in Polish Holstein-Friesians Based on Automatic Milking System Data.

The automatic milking system (AMS) provides a large amount of information characterizing the course of each milking cow, which is not available in the conventional system. The aim of our study was to estimate heritability and genetic correlations for milk yield (MY), milking frequency (MF), and speed (MS) for 1713 Polish Holstein-Friesian primiparous cows milked in barns with an AMS. Daily heritability indicators estimated using second-order Legendre polynomials and Random Regression Models showed high variation during lactation, ranging 0.131-0.345 for MY, 0.153-0.322 for MF, and 0.336-0.493 for MS. The rates of genetic correlation between traits ranged: 0.561-0.929 for MY-MF, (-0.255)-0.090 for MF-MS, (-0.174)-0.020 for MY-MS. It is possible to carry out effective selection for milking speed, which provides an opportunity to increase the number of cows per milking robot, and thus increase the profitability of production in the herd. The results proved that selection for milk yield and daily milking frequency is also feasible. The research showed a high, positive genetic correlation between milking frequency and milk yield, which allows us to conclude that preferring breeding cows with a natural tendency to frequent visits to the milking robot should indirectly improve the genetic basis of milking.

Prediction of cow's fertility based on data recorded by automatic milking system during the periparturient period.

The results of most studies show the beneficial effect of milking automation on production parameters of dairy cows, but its effect on fertility traits is debatable. Therefore, a study was undertaken to predict cow fertility - services per conception (SC) and calving interval (CI) - based on automatic milking system (AMS) data collected in the periparturient period subdivided into the second and first week before calving, 1-4, 5-7, 8-14, 15-21 and 22-28 days of lactation. SC and CI were predicted using daily indicators such as concentrate intake, number of milkings, cow box time, milking time, milking speed, colostrum and milk yield, composition, temperature and electrical conductivity. The study material was derived from the AMS management system and from the SYMLEK milk recording system. The analysis covered data for 16,329 milkings of 398 Polish Holstein-Friesian (PHF) cows, which were used in three AMS herds. The collected numerical data were statistically analysed by correlation analysis in parallel with decision tree technique (SAS statistical package). The present study showed that due to the low, mostly non-significant coefficients of correlation between AMS data collected between 2 weeks before and 4 weeks after calving, it is not possible to predict cow fertility based on single traits. It has been established that the decision tree method may help breeders, already during the postcalving period, to choose the level of factors associated with AMS milking, which will ensure good fertility of cows in a herd. The most favourable number of services per conception is to be expected from cows that were milked <1.6 times per day from 1 to 4 days of lactation and electrical conductivity of their colostrum did not exceed 69 mS during that time. In turn, shortest CI (366 days) will be characteristic of the cows whose average daily colostrum yield did not exceed 20.2 kg and their daily concentrate intake from 8 to 14 days of lactation was at least 5.0 kg.

Placental Characteristics Classification of Various Native Turkish Sheep Breeds.

The aim of this study was to classify placental characteristics of Akkaraman, Morkaraman, Karayaka, Awassi, Malya, and Bafra sheep breeds using the hierarchical clustering method. In total, 240 individual data records were used as experimental material. Placental characteristics such as total cotyledon surface area, small and large cotyledon length, small cotyledon depth, etc. were used as explanatory variables to classify the breeds' characteristics. Hierarchical clustering was used with the nearest neighbour method with Euclidean distance in order to classify the sheep breeds' variations. As a result, six breeds were separated into three clusters: the first cluster consisted of Bafra, Karayaka, and Awassi breeds; the second consisted of Akkaraman and Malya breeds; and the third cluster included only the Morkaraman breed. Bafra and Karayaka were pointed as the nearest breeds, with a similarity of 98.7% in terms of placental characteristics. The similarity rate of the Akkaraman and Malya breeds was at a level of 97.5%, whereas it was 96.8% for Bafra, Karayaka, and Awassi breeds. The similarity of Akkaraman, Karayaka, Awassi, Malya, and Bafra sheep breeds was estimated as 95.7%. The overall similarity was found to be at a level of 93.2% among sheep breeds. The outcomes of the study might be useful as a selection tool for reproductivity and can be used to select the breed to be reared.

New composite traits for joint improvement of milk and fertility trait in Holstein dairy cow.

OBJECTIVE: The objective of this study was to define a new composite trait for Holstein dairy cows and evaluate the possibility of joint improvement in milk and fertility traits. METHODS: A data set consisting 35,882 fertility related records (days open [DO], calving interval [CI], and number of services per conception [NSC], and total milk yield in each lactation [TMY]) was collected from 1998 to 2016 in Polish Holstein-Friesian breed herds. In this study TMY, DO, CI, and lactation length of each cow was used to obtain composite milk and fertility traits (CMF). RESULTS: Moderate heritability (0.15) was estimated for composite trait that was higher than heritability of female fertility related traits: DO 0.047, CI 0.042, and NSC 0.014, and slightly lower than heritability of TMY 0.19. Favourable genetic correlations (-0.87) were estimated between CMF with TMY. Spearman rank correlation coefficients between breeding value of CMF with DO, CI, and TMY were high (>0.94) but with NSC were moderate (0.64). Selection on CMF caused favourable correlated genetic gains for DO, CI, and TMY. Different selection indices with different emphasis on fertility and milk production were constructed. The amount of correlated genetic gains obtained for DO and total milk production according to selection in CMF were higher than of genetic gains obtained for DO and TMY in selection indices with different emphasis on milk and fertility. CONCLUSION: The animal selection only based on a composite trait - CMF proposed in current study would simultaneously lead to favourable genetic gains for both milk and fertility related traits. In this situation CMF introduced in current study can be used to overcome to limitations of selection index and CMF could be useful for countries that have problems in recording traits, especially functional traits.

Prediction of Lactational Milk Yield of Cows Based on Data Recorded by AMS during the Periparturient Period.

Early prediction of lactation milk yield enables more efficient herd management. Therefore, this study attempted to predict lactation milk yield (LMY) in 524 Polish Holstein-Friesian cows, based on information recorded by the automatic milking system (AMS) in the periparturient period. The cows calved in 2016 and/or 2017 and were used in 3 herds equipped with milking robots. In the first stage of data analysis, calculations were made of the coefficients of simple correlation between rumination time (expressed as mean time per cow during the periparturient period: second (14-8 days) and first (7-1 days) week before calving, 1-4, 5-7, 8-14, 15-21 and 22-28 days of lactation), electrical conductivity and temperature of milk (expressed as means per cow on days 1-4, 5-7, 8-14, 15-21 and 22-28), amount of concentrate intake, number of milkings/day, milking time/visit, milk speed and lactation milk yield. In the next step of the statistical analysis, a decision tree technique was employed to determine factors responsible for LMY. The study showed that the correlation coefficients between LMY and AMS traits recorded during the periparturient period were low or moderate, ranging from 0.002 to 0.312. Prediction of LMY from the constructed decision tree model was found to be possible. The employed Classification and Regression Trees (CART) algorithm demonstrated that the highest lactation yield is to be expected for cows with completed lactations (survived until the next lactation), which were milked 4.07 times per day on average in the 4th week of lactation. We proved that the application of the decision tree method could allow breeders to select, already in the postparturient period, appropriate levels of AMS milking variables, which will ensure high milk yield per lactation.

Forecasting the milk yield of cows on farms equipped with automatic milking system with the use of decision trees.

The purpose of this paper was to utilize the decision trees technique to determine the factors responsible for high monthly milk yield in Polish Holstein-Friesian cows from 27 herds equipped with milking robots. The applied statistical method-the decision tree technique-showed that the most important factors responsible for monthly milk yield of dairy cows using robots were, in descending order of importance: milking frequency, lactation number, month of milking, and type of lying stall. At the same time, it has been ascertained that the highest monthly milk yield (47.24 kg) can be expected from multiparous cows kept in barns with a deep bedding that were milked more frequently than three times per day. On the other hand, the lowest milk production (13.56 kg) was observed among dairy cows milked less frequently than two times a day, with an average number of milked quarters lower than 3.97. The application of the decision trees technique allows a breeder to select appropriate levels of environmental factors and parameters that will help to ensure maximized milk production.

Growth Performance, Body Measurements, Carcass and Some Internal Organs Characteristics of Pekin Ducks.

Native breeds of ducks have been the subject of many studies in the past, yet the relevant knowledge is still incomplete and needs to be further expanded. The objective of this study was to provide information about differences in growth performance, dressing percentage, carcass composition and digestive morphometry among three lines of Pekin ducks from conservation flocks raised in Poland. The study used 180 sexed Pekin ducks-30 males and 30 females of line P33 (ducks of Polish origin), 30 males and 30 females of line P8 (ducks of Danish origin), and 30 males and 30 females of line P9 (ducks of French origin). Throughout the study (49 d), ducks were confined indoors in six pens. Birds were fed complete commercial diets ad libitum and had unrestricted access to water. The compared lines of ducks differed significantly in body weight from 1 to 49 d of age except of ducks of both sexes at 14 d. At 49 d of age, significant differences were observed between the tested ducks in all the body measurements. Duck genotype had a significant effect on preslaughter body weight, carcass weight and breast muscle, neck and remainders contents, caeca length, liver weight and gizzard percentage. The results show that the tested ducks were significantly different and unique, mainly in terms of the body biometric characteristics.

A comparative study of carcass characteristics and meat quality in genetic resources Pekin ducks and commercial crossbreds.

OBJECTIVE: The study was aimed to compare carcass traits, physicochemical and textural properties of meat in two different genotypes of Pekin ducks with regard to sex effect. METHODS: The study involved 120 Pekin ducks - 30 males and 30 females of strain P33 (Polish native Pekin ducks) and 30 males and 30 females of Star 53 HY (commercial hybrid Pekin ducks). At 49 d of age, 48 birds (12 males and 12 females of each genotype) were selected for dissection. After the dissection, meat samples were collected to determine meat quality traits. RESULTS: The studied Pekin ducks of different genotype showed significant differences in body weight, carcass weight, dressing percentage, as well as percentages of breast muscles, skin with subcutaneous fat, abdominal fat, neck, and remainders of eviscerated carcass with neck. Duck genotype had an effect on the content of crude protein, crude fat, Na, K, P, Zn, pH24, electric conductivity (EC24), cooking loss, L*, a*, most textural traits of breast muscle, and also Na, Mg and Fe content, EC24, drip loss, cooking loss and L*, a* and b* colour coordinates of leg muscles. Regardless of genetic origin, males exhibited higher BW, carcass weight and carcass neck percentage, as well as lower redness, hardness, chewiness and gumminess of breast muscle compared to females. The genotype sex interaction was significant for the crude fat content and cooking loss of breast muscle, and for the yellowness of leg muscle. CONCLUSION: Star 53 HY ducks are more suited for broiler production due to their higher body weight and dressing percentage. Their breast and leg meat are characterized by more beneficial chemical composition but has poorer sensory and textural properties compared to the meat of P33 ducks.