The objectives were to evaluate the effects of sire and content of fresh or ionised egg yolk in extenders on sperm motility and share of live and dead sperm in collected ejaculate, in thawed artificial insemination (AI) doses, and during thermodynamic testing compared to extenders not containing egg yolk. Ejaculates were collected once a week from 4 Holstein bulls. Each of the 20 ejaculate samples from each bull was diluted with 4 different extenders. AndroMed and Bioxcell (no egg yolk) and Triladyl and Optidyl (fresh, ionised egg yolk) were used. A total of 640 AI doses were analysed. The volume of samples, sperm concentration, and percentage of motile spermatozoa were evaluated after collection, as was sperm motility after thawing of AI doses and during thermodynamic testing. Percentages of live and dead sperm were also evaluated. The data set was analysed using SAS/STAT 9.1 (SAS Institute Inc., Cary, NC, USA). The results confirmed significant (P<0.05-0.01) between-sire differences in the volume, density, and activity of sperm as well as in share of live and dead sperm after collection; in decline of sperm motility in the fresh ejaculate, after thawing, and during the entire thermodynamic test, as well as in the share of live and dead sperm after thawing. The extenders ranked by sperm motility are: Optidyl, Triladyl, AndroMed, and Bioxcell, demonstrating the higher quality of AI doses produced using egg yolk extenders. Differences in sperm motility were significant (P<0.05-0.01) during the entirety of thermodynamic testing. Egg yolk extenders had a significantly (P<0.05-0.01) higher percentages of live sperm after thawing.

Dairy cows of 2 breeds, 74 Holstein (H) and 72 Czech Fleckvieh (C) cows in the 1st (H, n=38; C, n=38) and 2nd lactation (H, n=36; C, n=34) during the 1st period (n=74; H, n=40; C, n=34; to 150 days) and the 2nd period of lactation (n=72; H, n=34; C, n=38; above 150 days) were observed. Differences in external and internal proportions of teat closely before (the 1st measurement), immediately after (the 2nd measurement) and 3 h after milking (the 3rd measurement), udder conformation evaluated by linear description, somatic cell count, daily milk yield and the time of milking were evaluated in relation to the effect of breed and period of lactation. The length of the teat canal, area of the teat end, and wall thickness were measured from the axial picture recorded by ultrasound Aloka SSD500 (Aloka Co., Ltd., Tokyo, Japan).Significant interbreed differences were detected in external as well as internal teat proportions (P<0.05-0.001). Relative changes of teat diameter, comparing C and H cows, differed significantly between the 1st and the 3rd measurement (P<0.05). The length of teat increased during milking and didn´t achieve the beginning size during 3 h after milking. Significant diiference in the length of teat between the 2nd measurement and the 3rd measurement was determined in H cows only (P<0.001). The most significant changes of the length of the teat canal and the area of teat were found in both breeds between values measured closely before and immediately after milking (P<0.5-0.001). Wall thickness was strengthen in C cows (+15.6 %) during the 2nd measurement according to the 1st (P<0.05), while difference represented +18 % (P<0.001) in H cows. Non-significantly higher values of external proportions of teat were measured in the 2nd period of lactation except diameter of teat closely before milking. Internal proportions of teat were always significantly higher in the 2nd period of lactation in relation to the 1st period. Prolongation of teat canal by 0.15 cm (P<0.01) closely before, by 0.16 cm (P<0.001) immediately after, and by 0.13 cm (P<0.01) 3 h after milking was measured in the 2nd period of lactation. The area of teat end measured before milking was significantly larger in the 2nd period of lactation (P<0.01). Keywords

Abstract. The aim of this review was to evaluate the relationship between the body condition of cows and reproduction. Reproduction was evaluated from the viewpoint of animal husbandry traits, ovarian activity and embryo transfer. Main emphasis was given to the review of articles from the area of biotechnical methods (in vitro embryo production, embryo transfer). Most authors agree on the opinion that the worsening of the reproduction traits of cows is a result of changes in the body condition score (BCS) either under or over their average value. Worsening of reproduction traits was presented not only from a zootechnical viewpoint (e.g., calving interval, 56 d nonreturn rate, etc.) but also in term of ovarian activity, oocyte recovery and in vitro embryo production. In general, the body condition of cows is an important factor affecting female reproduction ability at the ovarian level.

The aim of this study was to evaluate the polymorphic effects of two single nucleotide polymorphisms (SNPs) of fatty acid binding protein (FABP4) and stearoyl-CoA desaturase (SCD) genes on intramuscular fatty acid profiles in the longissimus muscle in two cattle breeds. Two previously reported SNPs of bovine FABP4 (7516G>C) and SCD (878C>T) were in turn assessed for their associations with intramuscular fatty acid profiles from the upper sirloin cuts of Aberdeen Angus and Blonde d'Aquitaine cattle. In total, 33 animals were genotyped using PCR-RFLP. Intramuscular fatty acid composition was evaluated using two complementary statistical approaches: a classical univariate regression model and a multivariate approach using a combination of Principal Component Analysis and Random Forests. Significant effect of FABP4

The effects of inbreeding level on service period (SP) and pregnancy length (PL) were monitored in Holstein and Czech Fleckvieh after the first calving. The levels of inbreeding (F X ) ranged from 1.25 to 25 %. SP and PL of inbred cows were compared with their outbred equals -half-sisters, sharing the same sire (n = 1824) and their first calving happened in the same farm and at the same time (± 3 month). Database with the number of 631 810 animals (year of calving 1985-2004) was used for analyses. Inbred cows were grouped according to F x coefficient (1.5-2.3 %; 3.0-5.0 %; 8.0-12.5 %; 25 %). The GLM with fixed effects (the breed, breeding value of the sire and monitored individual for milk production, year of calving, age at first calving) was applied to all data. The effect of inbreeding depression on SP was more pronounced at higher levels of inbreeding (+2.81; +3.35; +4.53; +8.23 d, respectively according to above mentioned F x groups) but non-significant. Differences in PL (+0.3; +0.32; -0.08 and 1.68 d) were not significant either. Average value of PL for inbred animals was 0.43 d higher. The correlation coefficient was +0.023 for SP and +0.0658 for PL. The F x coefficient increasing by 1 % extends the SP by 0.22 day and PL by 0.063 day. There was a higher variability of SP and PL in inbred cows. The length of calving interval between the first and second lactation is affected more by SP than PL.

Genetic effects, e.f. population and heterosis effects have been estimated for: Czech Fleckvieh, Beef Simmental and various types of their crosses produced in beef cow-calf operations. The best genetic-statistical model was chosen for the analyze of these effects. The fallowing traits were analyzed: birth weight, weights at 210 and at 365 days of age as well as average daily gains between birth and 210 days, between 210 and 365 days and between birth and 365 days of age. Parameters for all the traits were estimated by the method of least squares means with fixed effects year of birth, herd, sex, type of birth (single or multiple), age of dam and genotype. Genetic models involved the means and two to four crossbreeding effects: i.e. direct and maternal population effect and direct and maternal heterosis effect. The results showed that the genetic model including the mean and all four crossbreeding effects was more accurate and advantageous that the others. For all growth traits crossbreds exceeded both purebred populations. Positive values were estimated for most direct and maternal population effects. Direct and maternal heterosis effects in global showed negative values.

The aim of this study was to evaluate the effect of inbreeding on the yield and quality of bovine embryos. The data were obtained from 125 Holstein cows superovulated on 3 farms in the Czech Republic. In total, 125 flushings of embryos were analyzed, from which 761 embryos were obtained. Of all donors, 36 cows were inbred (199 embryos) and 89 cows were noninbred (562 embryos). The inbred cows were divided into 2 groups according to their inbreeding coefficient (F X ) level. The low F X group (F X 1.26%-1.56%) had 23 cows and 147 embryos, and the high F X group (F X 3.1%-25%) was represented by 13 cows and 52 embryos. The average value of the F X coefficient in inbred cows was 6.552%. The data were subsequently analyzed using PROC GLM of SAS as descriptive statistics and t-tests (SAS/STAT ® 9. 1., 2009). All evaluated traits in inbred cows had worse results than noninbred cows. Although there were poorer results for inbred versus noninbred cows, the differences were not great at lower F X values and were not statistically significant. Important and significant differences (P ≤ 0.05) were found in the proportion of transferable embryos and unfertilized oocytes at higher rates of F X .

Abstract. The objective of this study was to explore the effect of the level of inbreeding on the milk production (MP) and the breeding values (BV) of milk production. Data included cows calved in years 1990-2005 at farms in the Czech Republic. Inbred cows were grouped according to Fx coefficient (Fx = 1.25 %, Fx = 2.0–3.125 %, Fx = 4.0–12.5 % and Fx = total). MP and BV of inbred cows were compared with their outbred equals – half-sisters, sharing the same sire (n = 2,063), dam reached the same breeding value (±5 %) and their first calving happened in the same farm and at the same time (±2 months). The PROC GLM of SAS® with fixed effects (age at first calving, year of calving, number of lactations, first calving interval and relative breeding value of the sire and dam) was applied to all data. In the examined groups of Fx coefficient milk production of inbred cows at the first lactation decreased of −103.02, −236.8, −472.24 and −247.65 kg of milk. Also an insignificant increase of percentage of fat was found in most of the inbred groups: −0.0025, +0.1204, −0.0064 and +0.0708, as well as percentage of protein: −0.0063, +0.0365, −0.0346 and +0.0157. A similar tendency was also found when the milk production was represented by breeding values. Breeding value for milk in kg showed a decrease of −36.57, −43.55, −92.23 and −50.81 kg milk. Breeding value for fat percentage showed in inbred animals an increase of +0.0068, +0.0394, +0.0152 and +0.0251 %. A similar increase was also found in breeding value for protein percentage: +0.0015, +0.0216, −0.0035 and +0.0134 %. The Fx coefficient increasing by 1 % decreases milk production (regression coefficient) by 59.75 kg milk and increases fat and protein by +0.0112 % and +0.0030 %.