Abstract. The aim of this study was to compare the influence of propylene glycol and glycerin added to Total Mixed Ration (TMR) dose on lipid-carbohydrate metabolism, activity of selected liver enzymes and milk yield of Simmental cows in periparturient period. Forty two cows of Simmental breed were divided into 3 groups (n=14). Cows from the experimental groups were given 300 ml/d of either propylene glycol or glycerin from 7th day prepartum to 21st day postpartum. In week 5 of lactation in cows that were given propylene glycol and in week 12 in cows receiving glycerin Body Condition Score (BCS) was higher as compared to control cows. An application of glycerin resulted in the highest milk yield. Higher glucose content in groups that were given propylene glycol and glycerin would have contributed to the reduction of negative energy balance at the beginning of lactation. The lowest increase in aspartate transaminase (AST) and bilirubin level was observed in cows receiving glycerin. The study demonstrated that metabolic changes in Simmental breed cows in the periparturient period are dramatic, and an application of glucogenic precursors may improve metabolic efficiency.

The possible genetic impact of sire on cattle populations, herd milk yield and milk traits (fat and protein) have been described in the literature along with its impact on some milk indicators (MIs) as somatic cell count, urea and ketones. There is a dearth of information on the impact on a series of other MIs (physical, chemical, health, technological). The goal of this study was to assess the possible effect of sire on a wide range of MIs including technological properties in Czech Fleckvieh to suggest future possible breeding trends. A series of MIs (n=37) was investigated in individual milk samples (MSs). 191 effective daughters (MSs) were included. The sire groups (n=13) were well balanced in terms of herd, lactation stage and sampling season. Only sires with >5 daughters were ranked. A linear model of analysis variance with the fixed effects, sire and combined factor (herd × year × season) was used. 19 MIs as log count of streptococci in fermentation ability of milk (log FAM-CS), FAM-CS, log total fine microflora count in FAM (log FAM-TCM), FAM-TCM, solids non fat (SNF), iodine content, citric acid (CA), titration acidity in FAM, lactose (L), crude protein (CP), true protein (TP), casein (CAS), dry matter, Mg and P content, milk alcohol stability, electrical conductivity (EC), titration acidity, casein numbers (for CP and TP), log count of lactobacilli in FAM (log FAM-CL), FAM-CL and pH in FAM were influenced by sire (P<0.05). However SNF, CA, L, CAS and perhaps EC could be newly reflected as information for genetic improvement of dairy cattle with connection to dairy milk recovery and cow health. CA (10.08±1.92 mmol×l −1 ) deserves special attention. The model variablity explanation moved from 6.97 (SCC) over 29.51 (CA) to 48.32 % (pH) for MIs. This is one of few studies to assess the impact of sire over a wide range of MIs and the results warrant careful evaluation and further study.

The milk analyse result reliability is important for assurance of foodstuff chain quality. There are more direct and indirect methods for milk composition measurement (fat (F), protein (P), lactose (L) and solids non fat (SNF) content). The goal was to evaluate some reference and routine milk analytical procedures on result basis. The direct reference analyses were: F, fat content (Röse-Gottlieb method); P, crude protein content (Kjeldahl method); L, lactose (monohydrate, polarimetric method); SNF, solids non fat (gravimetric method). F, P, L and SNF were determined also by various indirect methods: -MIR (infrared (IR) technology with optical fi lters), 7 instruments in 4 labs; -MIR-FT (IR spectroscopy with Fourier's transformations), 10 in 6; -ultrasonic method (UM), 3 in 1; -analysis by the blue and red box (BRB), 1 v 1. There were used 10 reference milk samples. Coeffi cient of determination (R 2 ), correlation coeffi cient (r) and standard deviation of the mean of individual diff erences (MDsd, for n) were evaluated. All correlations (r; for all indirect and alternative methods and all milk components) were signifi cant (P ≤ 0.001). MIR and MIR-FT (conventional) methods explained considerably higher proportion of the variability in reference results than the UM and BRB methods (alternative).

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The aim was to evaluate the chosen relationships among milk composition, factors of primary milk production and milk thermostability (TES) on large data file during whole season (n 2,829). The results showed the TES mean 20.71 ± 8.19 minutes (geometric mean 19, median 20 minutes), from 3 to 57 minutes. Variation coefficient was 39.6%. The highest monthly mean was in September (23.98 ± 7.97, vx 33.3 % and xg 22.4 min.) and the lowest in January (16.5 ± 7.17, vx 43.5 % and xg 15.1 min.) and monthly mean values fluctuated (P < 0.001) in a relatively broad range of 7.48 minute (36.1 %). Weak positive correlation was found between the TES (also log TES) and log TCM (total count of microorganisms) and log COLI (count of coli microorganisms) as well (0.169 and 0.124; P < 0.01; n 1,353 and 1,355). The somatic cell count (SCC) showed no significant relationship with TES (P > 0.05). The surprising results are probably due to the lower variability and especially TCM, COLI and SCC level (248 ± 139 103ml-1; xg 218; vx 56.2 %; n 3,253) in the bulk milk. Significant effect on the TES was identified also in farms (P < 0.001). The results should contribute to an effective method of raw milk selection for dairy products with higher thermal stress during processing. The proposed selection limits for farms according to their history to predict better TES of raw material for 2 years of milk collection are: summer, TES mean over 17.5 minutes, variability up to 36.4 %; winter, over 13.0 minutes and up to 43.3 %.

No abstract

Abstract. This study was carried out on a commercial dairy farm located in the South-Moravian region of the Czech Republic. Two video cameras (IP7330 and PZ6122, Vivotek Technology), located over cubicles below the ceiling, provided video recordings, which were taken in 15-min intervals from 02.00 to 08.00 (Period 1 – morning) and from 10.00 to 19.30 (Period 2 – afternoon) one day per week (i.e. on Thursday) from 2 July (week 27) to 15 October (week 42). Air temperatures and humidity were measured every fifteen minutes during the days of behavioural observations using three HOBO data loggers. In order to determine the spatial distribution of dairy cows, the research barn was visually divided into three sectors of equal size: A – closest to the middle of the barn, B – between and C – the edge of the stable. Inside the barn, air temperatures predominantly ranged between 22 °C and 30 °C during Period 2, while in Period 1 they were lower by 5 °C to 11 °C. During Period 1, dairy cows were distributed quite evenly among sectors. Since week 29, however, the number of cows in sector A began to increase in Period 2 and did not return to the normal distribution pattern before week 42. Interestingly, the crowding was observed only during Period 2 and not in Period 1. Crowding began to appear when average daily temperatures increased to 20 °C.

ABSTRACT:The aim of the experiment was to compare the carcass composition of 20 Montbeliarde bulls (M) and 20 Czech Pied bulls (C). The carcass weight of the animals in one group varied minimally and was about 380 kg. The Montbeliarde bulls showed a higher growth rate, expressed by a significantly lower (P < 0.01) age at slaughter (562.6 vs. 626 days) while the live weight (682.9 vs. 690.6 kg) and carcass weight (380.4 vs. 382.6 kg) were comparable, which resulted in a significantly higher (P < 0.01) daily weight gain (1.142 vs. 1.045 kg) and net weight gain (0.676 vs. 0.615 kg). The Montbeliarde bulls showed a greater (P < 0.05) height at rump (144.0 vs. 140.2 cm), worse carcass conformation according to SEUROP (3.24 vs. 2.84), lower proportion of forequarter (44.7 vs. 45.7%) and higher proportion of hindquarter (55.3 vs. 54.3%). As for the carcass composition, no significant inter-breed differences were found in weights and proportions of shanks, meat trimmings, separable fat, bones, round, loin, filet, flank with rib, flank, shoulder and chuck. The Montbeliarde bulls had a significantly lower (P < 0.05) weight and proportion of neck (10.1 vs. 11.1 kg and 5.4 vs. 5.9%) and weight of brisket and rib (17.6 vs. 18.7 kg) and proportion of brisket and rib (9.4 vs. 9.9%, P < 0.01).