„milk“ 56 výsledků

This research was conducted on 147 cows of purebred Montbéliarde dairy cattle during their first to seventh lactation. On average, each dairy cow provided 161 values on live weight during lactation via the automatic milking system (AMS). The average live weight of a dairy cow of said herd was 699.94 kg, the daily milk yield was 33.67 kg on average and the average day of lactation (DIM) was 111.75. This research discovered a statistically significant decrease of live weight in dairy cattle before the 60th day of lactation in every observed lactation. On the contrary, the changes in live weight in the last 60 days of standardized lactation proved to be inconclusive. Between days 60 and 240 of the lactation, an increase of live weight of varying intensities was observed, mainly in cows who had undergone less lactation cycles in the past. Similarly, the research has proven an impact of the number of lactation cycles the cow has undergone in the past on the live weight of the cow during the first, second and third lactation (645.21 kg, 700.35 kg and 752.10 kg respectively). On the contrary, there was no conclusive difference in live weight between the third and more lactation cycles. The results have also shown that the changes in live weight during lactation were significantly different in first-calf heifers, as opposed to cows after more lactation cycles, similarly to the differences in milk yield.

The objectives of this study were to determine the relationship of oxidative product levels, using malondialdehyde (MDA) as a marker on occurrence of mastitis and its causing pathogens in two dairy flocks of ewes situated in east and north of Slovakia. The diagnosis of mastitis was performed on the basis of clinical examination of the udder, macroscopic evaluation of milk, with the evaluation of Californian mastitis test (CMT) and bacteriological analysis of individual raw milk samples. From total 537 and 444 halves ewe’s milk samples were 16.6% and 23.2% positive to CMT, respectively. The prevalence of mastitis caused by bacterial pathogenes in the monitored herds was 14.3% to 19.1%, respectively. In all monitored sheep flocks were confirmed predominantly subclinical forms (SM) of intramammary infection (IMI). The highest of etiological agents in all monitored herds had coagulase negative staphylococci and coagulase positive staphylococci especially Staphylococcus aureus. Except for staphylococci were Streptococcus uberis and Streptococcus spp. most frequently pathogens isolated from mastitic sheep. The highest MDA level was observed from clinical cases of mastitis however, increased MDA levels were detectable from subclinical cases. Bacterial isolates from mastitc halves milk samples are different in levels of MDA. In this study, we found that milk samples infected with S. aureus were higher compared to other pathogens. In conclusion, differences in both severities of IMI and mastitis pathogens were associated with differences of MDA in infected udders.

The climate in the Czech Republic is mild, transient between oceanic and continental, with a typical alternation of 4-year periods. The continental climate is characterized by high temperatures in summer and low temperatures in winter. During the extreme fluctuation of microclimatic conditions in the stable, there is also a change in individual reproductive indicators due to disruption of hormonal secretion, which further affects individual physiological processes, thus worsening conception or milder manifestations of heat, which we currently try to detect by neck responders and other modern systems.The experiment analyzed the effect of the average monthly temperature and humidity in the stable on the percentage of pregnant cows, in 2017 without the use of neck responders and in 2019, when all cows already had a neck responder. Monitoring was performed in 2017 and 2019 on the private farm GenAgro Říčany, a.s. (GPS 49 ° 12'32.319 "N, 16 ° 23'42.666" V). The values of average temperatures and relative humidity were calculated from 15-minute interval recordings of HOBO brand data loggers (Onset), which were placed in the stable, at the height at the withers of the cows without the possibility of influencing the measurements by the cows themselves. The object of monitoring was a herd of approximately 700 cows of Czech Fleckvieh Simmental various lactations. Data on the conception of cows were obtained both from the monthly reports of the breeding organization and from the data of the breeder.Thermal stress can have a long-lasting effect observable for weeks or months after the summer. This is also evidenced by the results of the work, which shows the worsening conception of cows, especially in late summer and autumn. At the same time, the results show a positive effect of the used neck responders, which help with the detection of heat and thus improve the reproduction of the whole herd.

The objective of this study was to analyse costs and incomes from milk/cheese and lamb production in dairy sheep flocks and to evaluate their economic efficiency by calculating the profit/loss that is expressed as the difference between these two economic indicators. Costs were calculated taking into account their individual item structure, revenues were calculated taking into account sales of milk/cheese and lamb production. The analysis included three-year period i.e. years 2017, 2018 and 2019. The object of investigations were twelve and thirteen dairy sheep flocks per year, respectively. Economic indicators were expressed in Eur per feeding day (costs) and/or in Eur per ewe and year (costs, sales, subsidies, profit/loss). Milk and lamb sales did not cover up costs spent on production and accounting for subsidy improved economic efficiency of dairy sheep only to a lower extent. Sheep farming thus produced with the loss. Across years, milk and lamb sales almost unchanged, whereas costs notably increased. No ability to cover up costs with revenues could become an obstacle for further survival of this livestock sector. The increase of both milk yield and lamb production is therefore needed.

The objective of this study was to analyse eight milk yield and longevity traits in dependence on feeding (grazing) system. Data of purebred Slovak Spotted dairy cows (35,812 heads) culled in the period between 2006 and 2019 were evaluated. Only herds those feeding (grazing) system was known were taken into account. Dairy cows were assigned to four groups: (1) heifers not grazed, cows not grazed (17,628 heads), (2) heifers grazed, cows not grazed (13,056 heads), (3) heifers not grazed, cows grazed (156 heads) and (4) heifers grazed, cows grazed (4,972 heads). The highest average 305-day milk yield (6,139.22 kg) and lifetime milk yield (18,606.78 kg) were found in animals of group (1). Contrariwise, longevity traits were found more favourable in animals of group (4). Their productive life was by 102.78 days longer and average parity was by 0.14 higher in comparison to group (1). The differences between groups were found significant.

The aim of this study was to evaluate lactose in relation to milk production and calving interval in dairy cows of Slovak Spotted cattle. A total of 92,730 lactations from 45,800 dairy cows evaluation from 2015 to 2019 were used for investigating lactose percentage (LP), milk yield (MY), lactose yield (LY), fat percentage (FP), proteins percentage (PP) and calving interval (CI). Data were analysed using the SAS version 9.4 and linear model with fixed effects: herd-years-season (HYS), sire (S), breeding type (BT), coding of milk (Cod-MY) and coding of calving interval (Cod-CI). In the dataset the average of LP was 4.77±0.20 %, while the one of MY, LY, FP, PP and CI were 6,778.53±2,014.18 kg, 325.27±100.45 kg, 3.96±0.47 %, 3.39±0.23 % and 406.66±91.09 days. The correlation of LP with MY, LY, FP, PP and CI was equal to r = 0.1712, r = 0.3157, r = 0.0546, r = 0.1852 and r = -0.0147. These correlation coefficients were statistically highly significant P <0.0001. Among all fixed effects in the analysis of variance of LP, the most relevant effect was observed for HYS (P<.0001).

Probiotics and prebiotics are effective to modulate optimal conditions in gastrointestinal tract inhabited by diverse microbial population. Probiotics regulate and modulate gut microbial population thus reducing the risk of diarrhea. Positive effect on growth is confirmed. The aim of this study was to evaluate the effect of probiotic (Lactobacillus sporogenes) and prebiotic (Ascophyllum nodosum) supplements on weight gain in calves. Forty new-born Holstein calves were randomised to control and experimental group. In the experimental group, Lactobacillus sporogenes and Ascophyllum nodosum were added first to colostrum and then to milk replacer, calves in the control group were fed with colostrum and milk replacer only. The weight gains of animals were found out during the whole experiment. Evidence of animal health and diarrhea was monitored. In the end of experiment, the body weight gains in experimental calves were by 14,4% higher compared to control but without statistical significance (P>0,05). Probiotic and prebiotic treatment tended to diminish diarrhea. The health benefits of monitored treatment were noticed in experimental group.

The study presents an approach to detect selection signals by the scan of runs of homozygosity (ROH) in two beef cattle populations bred Slovakia. The frequency and distribution of runs of homozygosity in the genome are affected by natural and artificial selection, recombination rate and structure of the population. After quality control, the final data set included 43,427 single nucleotide polymorphisms with overall length 2,504 Mb. Across the genome, sixteen regions under strong selection pressure with a total length of 73.94 Mb were identified. The functional analysis of selection signals revealed several quantitative trait loci for body structure, fitness and milk production. In the region with a high frequency of ROH reflecting the intense artificial selection genes related mainly to muscle development (MSNT, ROCK1, LAMTOR5) were observed. Besides, genes related to the control of the immune system (PTX3, FGL2) and reproduction (ADCYAP1R1) were localized within selection signals. The results confirm the intention to improve the production and reproduction traits of Charolais and Limousine cattle according to established breeding objectives for each breed.

The aim of the study is to evaluate the relation of protein nutrition to transformation of nitrogen (N) from feed to milk and its urinary excretion in dairy cows under the farm conditions. In breeding conditions of dairy farms in the groups of dairy cows in the 1st phase of lactation, with low content of CP (139±11.8 g/kg), optimum (161.8±6.3 g/kg) and high content of CP (179.7±8.5 g/kg) in dry matter of total mix ration (TMR), was confirmed the effect of increased the level of ammonia (NH3) in the rumen (17.4±1.7; 19.6±2.3; 22.8±3.4 mg/100 ml). The same tendency with higher statistical significance (P<0.001) was confirmed to the increased concentration of urea in the blood (22.8±3.7; 27.8±4.8; 35.1±6.6 mg/dl) and to the concentration of urea in the milk (18.2±2.6; 24.8±3.9; 33.3±6.7mg/dl). In the groups with increasing content of CP in the TMR, the ecological load of the environment increases, that was confirmed by a significant increase (P<0.001) of excreted N in the urine (139.4±19.8; 189.5±30.4; 254.7± 51.3 g N/day) and an increase (P<0.001) in the emission of ammonia into the environment (68.1 ± 6.1; 83.7 ± 9.4; 103.8 ± 15.9 g/day). The highest efficiency of N utilization at the level of 31.1 ± 1.4 % was confirmed at a CP content of 150-170 g/kg dry matter of TMR. The evaluation of direct regression dependence between the analysed CP content in TMR and analysed parameters of N transformation in individual farms was confirmed a significant relationship in CP and NH3 content (r = 0.641), CP and urea in the blood (r = 0.689) resp. CP and excretion of N in urine (r = 0.600). Direct relation was confirmed by the analysed NH3 content in the rumen and the urea content in the blood (r = 0.795), and urea in the milk (r = 0.786), as well as the urea content in the blood in relation to the urea in the milk (r = 0.767). The obtained results confirm the suitability of the use of the monitored markers to assess the level of protein nutrition and the environmental load at the farm.

The problem of the calf livestock to be preserved under the use restriction conditions of the antibiotics in case of the infectious diseases requires the search for alternative antimicrobial agents, to which the nanocompounds of the noble metals are belonged. The influence of the colloid silver solution on the indicators of the clinical condition, mineral turnover and morphological composition of the blood of the black-pied Holstein calves aged from birth to 30 days had been analyzed. It had been established that the calf rearing with the colloid silver solution composed of colostrum (milk) at a dose of 1.0 and 2.0 mg/l from the 1-st to the 10-th day every twenty-four hours, from the 11-th to the 30-th day, which is carried out once a decade, does not influence on the indicators of the clinical condition, but dose-dependently contributes to the increasing silver content in the blood. Nanosilver at a dose of 2.0 mg/l of colostrum causes the increasing iron and zinc accumulation in the blood of the calves on the 3-rd day after birth. With the increasing calf age up to 30 days as well as with the increasing oral use interval of the colloid silver solution, its influence on the exchange of zinc, iron and copper in the blood is decreased. On the 3-rd and 10-th day after the calf rearing with the colloid silver solution at a dose of 1.0 mg/l, the erythrocyte number reduction in their blood was found by 15.0 % and 12.3 %, the dose of nanosilver of 2.0 mg/l of colostrum causes a similar influence only on the 10-th day. On the 30-th day after the increasing interval of the calf rearing the erythrocyte number in the blood of both studied groups had been equal with the control one. The leukocyte number in the blood of the healthy calves practically did not depend on the dose of the colloid silver, as well as on its use period. The dose of the colloid silver equal to 2.0 mg/l of colostrum (milk) influences on the blood leukogram in a lesser extent than the dose equal to 2.0 mg/l, but both drug doses for 30-th day increase the lymphocyte percentage in the blood of the healthy calves. The obtained results make it possible to select an effective dose and interval of nanosilver application to the calves, taking into account the indicators of their clinical condition, mineral turnover and morphological composition of the blood, as well as to consider it as a prophylactic agent in case of the infectious diseases

The aim of this review is to consolidate the already much published knowledge concerning the gastrointestinal tract of the dairy cow in relation to nutrition. This review document deals with the essential living conditions of dairy cows, with an attention to nutrition, and highlights the importance of correct ration design. Dairy cows in different production cycles have special requirements for the composition, structure and nutrient composition of their rations. This review document provides more detailed information on the physical structure of feedstuffs as well as the need for individual nutrients for the right functioning of the dairy cow. These elements determine total health, feed intake, rumination, the development of metabolic diseases and last but not least, milk yield and composition. Rumination is an important and valuable tool that indicates the correctness of these aspects. Many published studies point to the relationship between rumination and health status where early intervention can be made to prevent a reduction in milk yield and consequent negative selection from the breeding stock. Many studies describe rumination as an indicator that forms the basis of the herd on which the very substantial and developing benefits of breeding as well as reproduction itself are built. The rumination-based relationships of heat stress and dairy cow health are also nowadays receiving a great deal of attention in studies. In nowadays also receiving a great deal of attention in studies about relationship not only between rumination - heat stress but also dairy cow health status. Heat stress is characteristically labelled as an unwanted factor that has an adverse effect on dairy cow milk yield.

The pilot survey among 36 Simmental cattle breeders in Slovakia was performed by an expert visiting farms and filling a questionnaire with farm managers. Data on the factors that influence the emission factors of ammonia, methane or nitrous oxide are needed to provide support for sustainable livestock production policies. Highest milk production (8305±828 kg) was found in the group with intensive production system comprising 7078 cows. Extensive systems were represented by only 2 farms with 451 cows producing 5527±1094 kg of milk. All farms used phase feeding, only 15% of all cows in the survey were grazing. The dominant way of handling animal waste was solid manure with straw bedding (30 farms), while slurry prevailed for the remaining farms. There were 8 farms (2095 cows) equipped with surface covered tanks, bags or using natural crust to reduce emission from slurry storage. Median emission factors of a dairy cow based on survey data were 137.21 kg, 0.850 kg and 50.79 kg per year for methane, nitrous oxide and ammonia, respectively. When aggregated by manure management, cows producing solid manure had a lower emission factor for methane but higher for ammonia and nitrous oxide compared to cows under liquid manure management. Linking data from various aspects of dairy production at farm level supports holistic approach as important for evaluation of food systems in the future.

The aim of this review, which has been compiled on the basis of the available existing literature, is to summarise the basic information regarding alimentary metabolic disorders in high-producing dairy cows. The disorders included in this review are among the most commonly occurring in herds. Specifically, ketosis, acidosis and milk fever. It is known worldwide that high producing dairy cows are more susceptible to ruminal dysfunction - alimentary metabolic disorders. Causes of alimentary metabolic disorders can be of different nature, such as unbalanced feed ration, stress, inadequate management and environmental factors, genetic factors and various infections or diseases of the animals. The most frequent cause of metabolic disorders is considered to be the feeding of an inadequate ration with an excess or deficiency of the required nutrients. Dairy cows must be fed a ration containing all nutrients in the correct proportions to maintain optimum metabolic function. The physical structure of the forage itself has a major influence on the health status of dairy cows and the development of dysfunctions, where not maintaining the correct technique (structure) has a negative impact on the overall rumen complex of the dairy cow.

The research of polymorphism of the PIT-1 and beta-lactoglobulin genes has been provided on the population of Ukrainian brown dairy and Sumy intrabreed type Ukrainian black-and-white dairy cows. The study of genotypes has been carried out using polymerase chain reaction in real time. The existence of interbreed differentiation in the frequencies of genotypes and alleles of the studied genes has been proved. The influence of the studied genes genotype on individual indicators of milk productivity of cows has been established.

This review aims to highlight the importance of genetic evaluation of health traits. In the past, cattle breeding primarily focused on milk production traits, but nowadays, there is a shift towards considering health traits and longevity. Cows are mainly affected by four diseases: mastitis, claw diseases, metabolic diseases, and reproductive diseases. These ailments negatively impact milk production, impair reproduction, and incur high treatment costs. In 2012, the ICAR implemented guidelines for the genetic improvement of health traits, establishing a system for recording diseases and their key indicators. This system includes a comprehensive key (>900 diagnoses), a reduced key (60 to 100 diagnoses), and a simple key (10 diagnoses). Genetic evaluation of health traits started in the mid-70s in Nordic countries. Previously, Czechoslovakia had a system for evaluating and classifying the overall health of breeding cows and bulls. In Slovakia, genetic evaluations for milk production traits, somatic cell score, calving ease, and longevity are performed. However, these traits are not included in the selection index along with health traits, for which genetic evaluations are not made. Two selection indexes are currently used: the Slovak Holstein Index, which takes into account milk production traits and type traits at 60% and 40% respectively, and the Slovak Production Index, which takes into account milk production in kilograms, fat production in kilograms, and protein production in kilograms.

The colostrum consumed by newborn ruminants immediately after birth plays a crucial role in ensuring their long and healthy lives. It is their first nutrition, supporting growth, development, and immunity against diseases. The study involved eight goat crossbreeds of Saanen × Makatia and Saanen × Alpine goats, raised in the Ghardaia region, known for its arid climate. Colostrum samples were collected during four days after kidding. Each sample was subjected to the evaluation of the microbiological quality and the key physicochemical properties, including fat and protein content, pH, titratable acidity, density, conductivity, appearance, and colour. The results showed a decrease in fat and protein content from day one to day four in both goat populations, although the differences in the four-day averages were not significant. Acidity and density also followed a decreasing trend, with the difference in four-day averages being significant in the Saanen × Makatia group. In terms of pH, variation over the four days was not significant. Conductivity values increased consistently in both populations. Microbiological analysis revealed the absence of sulphite-reducing Clostridium, Salmonella, and yeasts in all samples. The counts of Staphylococcus aureus, total aerobic mesophilic flora, and total and faecal coliforms remained within acceptable limits for raw milk, indicating that the colostrum was of satisfactory microbiological quality.