Czech Journal of Animal Science, 2020 (vol. 65), issue 4
Cryopreservation of boar semenReview
Marija Jovičić, Eva Chmelíková, Markéta Sedmíková
Czech J. Anim. Sci., 2020, 65(4):115-123 | DOI: 10.17221/47/2020-CJAS 
Sperm cryopreservation is the best technology for long-term storage of the semen. However, the damage of boar spermatozoa by cryopreservation is more severe than in other animal species and a standardized freezing protocol for efficient cryopreservation has not been established yet. Semen quality and freezability vary greatly between breeds as well as between individual boars and even the season. Boar spermatozoa are sensitive to low temperatures; they sustain damage and a high rate of mortality and freezing/thawing the boar semen may strongly impair the sperm function and decrease the semen quality. The freezability of boar semen can be influenced...
Evaluating the economic profit of reproductive performance through the integration of a dynamic programming model on a specific dairy farmOriginal Paper
Lenka Krpálková, Niall O'Mahony, Anderson Carvalho, Sean Campbell, Joseph Walsh
Czech J. Anim. Sci., 2020, 65(4):124-134 | DOI: 10.17221/38/2020-CJAS
The overall objective of this study was to improve the reproductive efficiency of lactating dairy cows and to improve the resulting total farm profit. The hypothesis is that a dairy farm can substantially improve its economic and environmental performance through increasing pregnancy rate, i.e. increasing the number of eligible cows that become pregnant for a given breeding period. This paper presents a tool which was designed with a view to comparing the reproductive efficiency. The tool was developed using dynamic programming in R (Shiny) and shows the changes in costs, revenues and net return projected for a given change in pregnancy rate....
Enteric methane emissions in crossbred heifers fed a basal ration of low-quality tropical grass supplemented with different nitrogen sourcesOriginal Paper
Afaf Abdelrahman Elshereef, Julian Arroyave-Jaramillo, Lucas Miguel Zavala-Escalante, Angel Trinidad Piñeiro-Vázquez, Carlos Fernando Aguilar-Pérez, Francisco Javier Solorio-Sánchez, Juan Carlos Ku-Vera
Czech J. Anim. Sci., 2020, 65(4):135-144 | DOI: 10.17221/256/2019-CJAS
The aim of the present study was to assess enteric methane (CH4) emissions by crossbred heifers fed a basal ration of low-quality tropical grass supplemented with different nitrogen sources. Four crossbred heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 355 ± 6.01 kg were used in a 4 × 4 crossover Latin square design with four periods of fifteen days each. Basal ration was chopped low-quality tropical grass Pennisetum purpureum fed to cover ~70% of metabolizable energy requirements for maintenance of heifers and it was supplemented with either poultry litter (control ration, T1), urea...
Effects of fermented Caragana korshinskii on the intramuscular fat content and expression of FABP3, UBE3C, ADRB3, LIPE, and SCD in different muscles of Tan sheepOriginal Paper
Xiaochun Xu, Tingda Liu, Shanshan Fan, Wenping Ma, Wenjuan Chen, Xiu Zhang
Czech J. Anim. Sci., 2020, 65(4):145-152 | DOI: 10.17221/231/2019-CJAS
The aim of this study was to investigate the effects of fermented Caragana korshinskii on the intramuscular fat content and varied expression of the intramuscular fat deposition-related genes FABP3, UBE3C, ADRB3, LIPE, and SCD among four muscle tissues (m. psoas, gluteus, quadriceps, and supraspinatus) of Tan sheep. Twenty-eight male animals of similar age (270 ± 10 days) and weight (24.6 ± 1.06 kg) were randomly divided into a control group (fed the basal diet) and an experimental group (fed the same diet except 10% of corn stalks were...