The objective of this study was to evaluate the influence of negative energy balance on fatty acids proportion in the milk of Czech Fleckvieh cows after calving. Milk quality was determined based on fatty acid group proportion. Milk quality was evaluated in relation to selected negative energy balance (NEB) traits: body condition change (DEC) and milk citric acid content (CAC) after calving. Milk samples (n = 992) were collected once per week from 248 Czech Fleckvieh cows during the first month of lactation. Fatty acid content (%) in milk samples was determined and results were grouped as saturated (SFA) (hypercholesterolemic or volatile fatty acids) or unsaturated (UFA) (monounsaturated or polyunsaturated). Our results showed that cows with a deep NEB produce milk that is healthier for human consumption. Cows with a more significant DEC or the highest level of CAC in milk had the lowest proportion of SFA and the highest proportion of UFA (p < 0.01). These cows experienced higher physiological stress after calving; however, they produced milk of higher nutritional quality. Nowadays, we can see preventive efforts to mitigate NEB periods as a result of modern breeding trends regarding vitality, robustness, or longevity.

The aim of this study was to evaluate differences in milkability based on lactation peak and parity in Holstein cattle. Milk yield, actual milking time, milking time differences, occurrence of bimodal milk flow, average and partial milk flows within the first two minutes of milking were monitored...

The aim of this work was to evaluate influence of milking settings optimization on milk yield (MY), milking time (MT), average milk flow (AMF) and somatic cell count (SCC). Pulsation ratio was changed from 60:40 to 63:37; pulsation rate from 60 to 62 pulses per minute; and critical milk flow for automatic cluster remover (CMF) was decreased from 0.85 to 0.65 kg.min^-1. Experiment was conducted on Holstein production herd (n=370) from March to May. SAS 9.3 was used for statistical evaluation. Changes significantly influenced all evaluated parameters (P <0.05). Slightly higher MY (+0.16 kg, P <0.05) was observed before changes. Naturally, the milking time was significantly prolonged (+0.26 min; P <0.01) by decreasing the CMF. This change also prolonged decline phase of milking, so the AMF was significantly reduced (-0.17 kg.min^-1, P <0.01). On the other hand, MT prolongation was not that critical due to increases in pulsation settings, which helped to reduce the negative influence of lower CMF on MT. Milking setting adjustments had positive effect on udder health, with significant drop in SCC (-64.78 thous./ml, P <0.01). In conclusion, milking settings adjustments are viable way of achieving various farm goals; like better udder health, less residual milk and many more.

The main objective of this research communication was to explore the extent of milkability changes caused by the incidence of clinical mastitis. Our second objective was to investigate if the milkability of cows shortly before mastitis incidence significantly differed in comparison with healthy cows. Milk yield, milking time, average milk flow, partial milk flows and the occurrence of bimodal milk flows were monitored during the first 120 d in milk for all cows that calved on the farm during the experimental period (n = 127). A veterinarian diagnosed 27 cows with clinical mastitis, while the remaining healthy cows served as a control group. The period surrounding the mastitis was monitored in a timeline from 2 weeks before to 4 weeks after the diagnosis. We did not observe any significant differences in milkability between the healthy cows and the cows in the pre-mastitis period, which suggests that monitoring these might not be useful for early mastitis detection. Milk yield and milk flow were significantly decreased in the week of mastitis diagnosis compared to the pre-mastitis period. Milking time was not affected in the week of diagnosis, but was significantly increased in the following week, because milk yield returned to pre-mastitis values, but average milk flow was still significantly decreased. Milk yield was normalized to pre-mastitis values as the first of monitored parameters. Milk flow returned to pre-mastitis values in the fourth week after mastitis diagnosis. Milking time was the only parameter that was significantly affected up to a month after diagnosis. Our results showed that milkability changes caused by mastitis are significant and should not be ignored. The ability to adjust milking settings for cows diagnosed with mastitis could become a useful tool for improving mastitis treatment.

Dairy cows enter the negative energy balance in?the early post-partum period, which negatively affects milk yield, health status and reproduction. This study aimed to?determine if milk yield (MY) and fat/protein (F/P) ratio could be used as?re...

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