Template-Type: ReDIF-Article 1.0 Author-Name: Jaroslav Valenta Author-Workplace-Name: Department of Animal Science, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Aftab Siddique Author-Workplace-Name: Department of Poultry Science, Auburn University, Auburn, Alabama, USA Author-Name: Eva Tůmová Author-Workplace-Name: Department of Animal Science, Czech University of Life Sciences Prague, Prague, Czech Republic Author-Name: Ondřej Slavíček Author-Workplace-Name: Department of Informatics in Transport, University of Pardubice, Pardubice, Czech Republic Author-Name: Amit Morey Author-Workplace-Name: Department of Poultry Science, Auburn University, Auburn, Alabama, USA Title: White striping, woody breast and spaghetti meat: Cooccurrence and relationship with breast fillet weight in big broiler chicken flocks Abstract: The present study aimed to determine the incidence and coincidence of white striping (WS), woody breast (WB) and spaghetti meat (SM) in raw chicken breast meat (n = 300) collected 3-3.5 h post mortem from commercial broiler flocks (Ross 708 males, 56 days of age). The fillets were scored for the occurrence and severity of WS, WB and SM using visual and tactile methods, and the relationship between myopathies and breast weight was evaluated. A total of 88% of samples (out of 300) had either one or a combination of three myopathies, leaving only 12% without any myopathies. Approximately 29% of the fillets had only one myopathy present, with 59% of the samples demonstrating the cooccurrence of breast myopathies. In the present study, 47.7% of WB samples also exhibited WS, while the cooccurrence of WB and SM was exhibited in 14.7%. Based on binomial logistic regression, an increase in WB scores decreases the odds that the fillet may be affected by SM myopathy. No association was found between SM and fillet weight. Multinomial logistic regression showed that the weight of breast fillets was positively associated with WB1 (P = 0.011), WB2 (P < 0.001), and WB3 (P < 0.001). Furthermore, positive associations were found between WS1 and WB3 (P = 0.004) as well as between WS2 and WB3 (P < 0.001). The percentage distribution changes of each WB and WS myopathy score were used in relation to the 10 weight groups. The percentages of WB3 increased and WB0 decreased as the average fillet weight increased. Regarding linear regression, these results exhibited a positive linear relationship for both WB (R2 = 0.91, P < 0.001) and WS (R2 = 0.71, P = 0.002) myopathy with fillet weight. A high prevalence of myopathies was observed. The incidence of severe WB categories and the overall high cooccurrence rate are alarming. Keywords: fast-growing chickens, breast meat, myopathy, incidence, poultry Journal: Czech Journal of Animal Science Pages: 129-140 Volume: 68 Issue: 3 Year: 2023 DOI: 10.17221/173/2022-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/173/2022-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202303-0001.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:3:id:173-2022-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Han Zhang Author-Workplace-Name: Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Workplace-Name: Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Name: Zhexi Liu Author-Workplace-Name: Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Workplace-Name: Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Name: Yijun Liu Author-Workplace-Name: Zhaohua District Agriculture and Rural Affairs Bureau of Guangyuan City, Guangyuan, P.R. China Author-Name: Depeng Wang Author-Workplace-Name: Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Workplace-Name: Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Name: Ji Wang Author-Workplace-Name: Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Workplace-Name: Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Name: Keliang Wu Author-Workplace-Name: Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Author-Workplace-Name: Key Laboratory of Animal Genetics, Breeding and Reproduction of the Ministry of Agriculture and Rural Affairs, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China Title: Relationships between gilt development and herd production efficiency are revealed by simulation Abstract: The gilt development level is a critical factor for profitability in the pig industry. To evaluate the impact of different gilt development levels on the age structure and production efficiency of female herds we used the performance data of a pig farm that was simulated over a ten-year period, with current production statistics from the Chinese pig industry as a basis for the model. In a herd of 600 breeding sows, we compared age structure, number born alive (NBA), longevity and sow lifetime productivity in three scenarios with gilt culling rates of 10%, 20%, and 30%. The results show that the gilt development has no significant effects on the age structure. The gilt development had no significant effects either on sow reproductive performance or production efficiency. However, the annual replacement rate, longevity, and sow lifetime productivity varied significantly in the three levels of gilt development (P < 0.01). We conclude that the gilt development is closely related to herd turnover and reproductive performance, and ultimately affects the cost of pig production. Gilt development is, therefore, an extremely important factor in an integrated pig production system. Keywords: pig, computer simulation, performance of gilt, age structure, productivity Journal: Czech Journal of Animal Science Pages: 122-128 Volume: 68 Issue: 3 Year: 2023 DOI: 10.17221/127/2022-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/127/2022-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202303-0002.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:3:id:127-2022-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Daniel Falta Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Lenka Zapletalová Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Oto Hanuš Author-Workplace-Name: Dairy Research Institute Ltd, Prague, Czech Republic Author-Name: Josef Kučera Author-Workplace-Name: Czech Moravian Breeders Association, Hradištko, Czech Republic Author-Name: Milan Večeřa Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Gustav Chládek Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Radek Filipčík Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Tomáš Kopec Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Author-Name: Francois Stefanus Lategan Author-Workplace-Name: Department of Livestock Science, Mendel University in Brno (FA), Brno, Czech Republic Title: The interaction between the milk production, milk components with a low frequency of analysis and factors affecting the milk composition in dual-purpose Simmental cows Abstract: The aim of this study was to improve the understanding of the contribution of components typically found in milk, but which are not often included in analyses, to the nutritional status of dairy cows. This was undertaken by analysing the amount and composition of milk produced by Simmental dairy cows, a dual-purpose breed farmed in the Czech Republic. Apart from the more frequently analysed group of components in milk, a less frequently analysed group of components were also investigated. This group, typically, consists of the following components: urea, casein, citric acid, beta hydroxy butyrate (BHB) ketones and free fatty acids. The average content of urea, casein and citric acid in milk is 25.75 mg/100 ml, 2.96%, 0.15%, respectively. The influence of environmental factors on these indicators was evaluated, as well as the degree of hereditary establishment. These less frequently analysed components (indicators), as well as the more frequently analysed components of milk, are subject to several external influences, especially the influence of the breeder, the year and the season of calving. The content of these components varied significantly statistically during the lactation period and also in the order of lactation. The influence of a cow's individuality and the degree of additive genetic background are evident, with estimated heritability coefficients ranging from 0.04 for the BHB ketone content to higher values, e.g., 0.28 for citric acid or 0.31 for the lactose content in milk. The relationships between the components of milk and the daily milk yield were also evaluated, and statistically significant negative correlations were found between the content of casein and the daily milk yield (-0.47) and between the lactose content and the number of somatic cells (-0.37). Keywords: Czech Fleckvieh, dairy, heritability, parity, calving season Journal: Czech Journal of Animal Science Pages: 99-110 Volume: 68 Issue: 3 Year: 2023 DOI: 10.17221/197/2022-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/197/2022-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202303-0003.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:3:id:197-2022-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: Radko Loučka Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Filip Jančík Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Dana Kumprechtová Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Veronika Koukolová Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Petra Kubelková Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Yvona Tyrolová Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Alena Výborná Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Miroslav Joch Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: Václav Jambor Author-Workplace-Name: NutriVet Ltd, Pohořelice, Czech Republic Author-Name: Hana Synková Author-Workplace-Name: NutriVet Ltd, Pohořelice, Czech Republic Author-Name: Soňa Malá Author-Workplace-Name: NutriVet Ltd, Pohořelice, Czech Republic Author-Name: Jan Nedělník Author-Workplace-Name: Agricultural Research Ltd Troubsko, Troubsko, Czech Republic Author-Name: Jaroslav Lang Author-Workplace-Name: Agricultural Research Ltd Troubsko, Troubsko, Czech Republic Author-Name: Petr Homolka Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Workplace-Name: Department of Microbiology, Nutrition and Dietetics, Czech University of Life Sciences Prague, Prague, Czech Republic Title: Using precision livestock farming for dairy herd management Abstract: The aim of this study was to validate selected precision livestock farming (PLF) methods of nutrition and feeding management of high-yielding Holstein dairy cows. In a feeding trial with 36 dairy cows, the effect of replacing 0.1 kg of sodium bicarbonate in the control total mixed ration (TMR-C) with 1 kg of wheat straw in the experimental total mixed ration (TMR-S) on the physiological status of cows and the amount of milk produced (milk yield, MY) was investigated. Feed intake time (FT), as measured using tensometric feed troughs (TFT), was significantly longer with TMR-S (188 min) than with TMR-C (157 min). Differences between TMR-C and TMR-S were not significant for FT or rumination time (RT), as measured by a sensor in the collar (VSC). There was only a weak correlation between the two technologies (TFT vs. VSC) for FT (r = 0.27). Differences between TMR-C and TMR-S were not significant for values measured in rumen fluid (pH, acid and ammonia levels) nor for values measured by sensors in the milking parlour (MY, fat and protein percentage of milk). Milk analysis in the laboratory showed that the cows fed TMR-C had higher urea (26.6 vs. 22.7 mg/100 ml) and free fatty acid (0.87 vs. 0.33 mmol/100 g) levels in milk. Moderate correlations were between TMR intake and MY (r = 0.55); between MY and milk fat (r = -0.46); between milk fat and milk protein (r = 0.63); and between milk fat and milk protein measured by sensors and in the laboratory (r = 0.47 and r = 0.42, respectively). In view of the above results, further research and data validation for each technology are needed. Keywords: ruminant nutrition, rumination, rumen pH measuring bolus, milk yield Journal: Czech Journal of Animal Science Pages: 111-121 Volume: 68 Issue: 3 Year: 2023 DOI: 10.17221/180/2022-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/180/2022-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-202303-0004.txt Handle: RePEc:caa:jnlcjs:v:68:y:2023:i:3:id:180-2022-CJAS