The goal of this study was to analyze the genetic and environmental factors of selected meat yield indicators in Fleckvieh cattle in the Czech Republic, through the application of station (S) and field (F) testing methods. Data collected from fattened bulls were analyzed for F (n = 9378) and for S (n = 6346). In the F method and the S method, the values of the main meat yield indicators were as follows: carcass weight 402.91 kg (F), 339.37 kg (S); carcass daily gain 626.05 g/day (F), 609.74 g/day (S); SEUROP carcass classification 2.73 (F), 2.19 (S). Environmental factors were found to have a significant impact on the selected meat yield indicators; their heritability ranged from 0.14 (SEUROP classification) to 0.33 (dressing percentage). The genetic trend was significantly positive only in relation to those meat yield traits, which had a positive link to the size or weight of the animal. The genetic correlation between observations obtained in the S and F methods of testing was very high in relation to the carcass daily gain (0.8351) and carcass weight (0.8244), while slightly lower correlations were calculated for the SEUROP classification. A genetic evaluation of the degree of fatness is not routinely performed in Fleckvieh populations, and the newly established heritability for this trait ranges between 0.17–0.20. The genetic correlation between beef yield indicators and the exterior trait of muscularity was also established, and shows a strong link to the net daily gain, the SEUROP classification and body weight (0.79–0.97). The aim of the study was to evaluate the genetic and environmental effects on meat yield and also estimate genetic parameters for new traits. We can also state, based on the results, that a strong positive genetic trend is confirmed, especially in traits related to the size or weight of animals. This result can be used in breeding programs of dual-purpose cattle, where we can genetically improve the meat and milk yield through the body size.

Objective: This study was focused on the estimation of parameters of Wood’s model and description of the lactation curve using the cows which were lactated over 24 months on the first lactation.Methods: The database included 1,333 pure-bred dairy Simmental primiparous cows which lactated for 24 months (732 days). The initial dataset entering the procedure of assessment of parameters of Wood’s function included 35,826 milk yield records. Milk yield was recorded throughout lactation, with the earliest record taken on day 6 and the latest on day 1,348 of lactation. This dataset was used for the assessment of parameters a, b, c of Wood’s model using the non-linear statistical procedure. These parameters were estimated for different length of lactation. The assessed parameters were used for calculation of some characteristics of lactation curves.Results: The lowest value of a parameter (15.2317) of Wood’s model of lactation curve was found out in lactations up to 305 days long, contrary to b and c parameters which were highest in those lactations (0.1029 and 0.0015, respectively). The maximum value of a parameter (17.4329) was found out in lactations up to 640 days long, unlike b and c parameters which were minimal in those lactations (0.0603 and 0.0010, respectively).Conclusion: It can be concluded that the parameters of Wood’s model and the shape of lactation curve are changing with the growing number of milk yield records. Also, the assessed parameters revealed a significant milk production potential after 305 days of lactation.

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, the scientific journal of the Mendel University in Brno, Czech Republic

A group of 98 Czech Fleckvieh cows (one section) was observed over the period of one year with the aim to determine the variation in their milk performance and behaviour at different cowshed temperatures. Behaviour and milk yield were recorded once a week (on the same day) at 10:00. Periods of 8 weeks with the highest temperature (hot period - H) and of 8 weeks with the lowest temperature (cold period - L) were then compared. The cows were housed in one section (1/4 of the total capacity) of the free-stall cubicle shed and where the cubicles were distributed into three rows. Row A (32 cubicles) was close to the feeding plateau, row B (33 cubicles) was in the centre and row C (38 cubicles) was peripheral, close to the side wall. The cowshed temperature was monitored on a daily basis and the mean temperature was 23.2°C in the hot period and -1.7°C in the cold period, relative humidity 60.2% (H) and 74.6% (L), and THI 69.4 (H) and 33.4 (L). The behaviour of the cows was recorded 1568 times, showing them mostly lying down (1037) or standing (531). The cows tended to prefer lying down on their left sides (594 observations) as opposed to their right sides (443). Row A was favoured by the cows (418) and row B was the least popular (377). The cows produced significantly more milk in H period than in L period (0.3 kg per day). The cows lying down were older (3.18 lactations) than the standing cows (2.99 lactations) and they tended to produce more milk per day (by 0.6 kg) but the difference was found to be insignificant. The cows lying resting on their left side produced more milk per day (0.9 kg) and were older (0.02 lactations). The cows in row C were the youngest (2.94 lactations) and the cows in row B were in the last days in milk (144.1 days).

The objective of this study was to determine the effect of growth rate on some beef performance characteristics in Czech Fleckvieh heifers. Growth performance characteristics included age at slaughter (months) and daily weight gain (g). The observed beef performance characteristics were carcass weight, conformation class (SEUROP) and external fat deposition. The experimental group consisted of 480 heifers. The animals were assigned into three groups (A, B, C) based on age at slaughter. Group A consisted of 68 animals with the age at slaughter 15–21 months, group B 296 animals, age 22–28 months and group C 116 animals, age 29–35 months. A greater age at slaughter was significantly associated with a greater carcass weight which grew from 250.78 kg in group A to 317.69 kg in group C. The net weight gain decreased with age from 424.06 g in group A to 346.41 g in group C, the conformation improved from 4.46 in group A to 4.17 in group C and the external fat deposition increased from 2.5 in group A to 2.78 in group C. The dataset was again split into three groups differing in the daily weight gain (I, II, III). Group I consisted of 120 heifers with the daily gain up to 599 g, group II 303 animals with the daily gain of 600–799 g and group III only 57 animals with the gain of 800 g and more. A growing weight gain was significantly associated with a greater carcass weight (from 260.40 kg in group I to 338.66 in group III), a greater net weight gain (from 306.29 g in group I to 491.45 g in group III), improved conformation (from 4.75 in group I to 3.70 in group III) and the fat deposition was greater, too (from 2.35 in group I to 2.89 in group III).