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Staphylococcus aureus is an important causative agent of subclinical bovine mastitis worldwide. The aim of this research was to study the ability of S. aureus to form biofilms. Additionally, we examined the genes involved in cell resistance and sensitivity to antibiotics. Samples were collected from December 2020 to May 2021 from Simmental and black-and-white cows. The study was carried out on a total number of 643 cows, of which 278 (23 %) were in the subclinical mastitis stage. Finally, 64 S. aureus isolates were isolated and identified. The highest level of phenotypic resistance was observed to antibiotics of the tetracycline (tetracycline – 48.4 %, doxycycline – 32.8 %) and β-lactam (ampicillin – 45.3 %, penicillin – 45.3 %) groups. The genes encoding antibiotic resistance were characterized with the polymerase chain reaction method: blaZ in 30 isolates, mecA in 1 isolate, ermC in 15 isolates, aph (3) in 2 isolates, tetK in 19 isolates, tetM in 9 isolates. The tested S. aureus isolates had the ability to form biofilms in 76.6 % (49/64) of cases. Of these, 69.4 % were resistant to at least one antibiotic. The obtained results have shown that S. aureus, identified in cows with subclinical mastitis, was resistant mainly to tetracycline and β-lactam antibiotics. In addition, S. aureus isolates expressed resistance genes to the above drugs and had the ability to form biofilm. This study will help to identify the extent of antibiotic resistance and monitor S. aureus contamination of raw milk.

Yoghurt is one of the well-known fermented dairy products that play an important role in the human diet. At present, products made of goat's milk are becoming more popular. This study was conducted to evaluate the effect of physicochemical properties of yoghurt fortified with vitamin C. Six different yoghurts were developed: from goat's and cow's milk without any addition, with L-ascorbic acid and acerola addition. The results showed that the addition of L-ascorbic acid significantly decreased pH. Based on the sensory evaluation, the natural cow's yoghurt has scored higher in the overall rating among yoghurts. The addition of L-ascorbic acid to natural goat's yoghurt positively affected the color, taste, flavor, and consistency. In the case of cow's milk yoghurt, the addition of L-ascorbic acid and acerola deteriorated the taste of the product.

Simple Summary Selenium (Se) plays an important role in many biological functions, especially in the immune system. We studied the effects of injectable Se supplementation on the immune status, blood parameters, body weights and average daily gain of lambs. The results of the study indicate that the Se preparation induced an increase in the values of the parameters of both non-specific and specific immunity. Lambs from the experimental group achieved higher body weights and daily gains. The present findings can contribute to a better understanding of the biological functions of Se and improve the efficacy of this mineral in livestock production. Abstract The aim of this study was to determine the effects of long-acting selenium (Se) preparation in sheep. The experimental material comprised Skudda ewes and their lambs. The animals were divided into two equal groups: C-control, and E-experimental. Between days 70 and 80 of pregnancy, group E ewes were injected with Se preparation (Barium Selenate Injection, BVP Animal Care, Ireland) at f 1 mL/50 kg body weight. Hematological, biochemical and immunological blood parameters as well as Se levels were analyzed in ewes. The growth rate of lambs, the dimensions of the musculus longissimus dorsi (MLD) cross-section, and fat thickness over the loin-eye area were also determined. It was found that barium selenate stimulated the mechanisms of humoral and cellular immunity. The injection was an effective form of Se supply, which was confirmed by its increased concentration in the blood serum of lactating ewes. The offspring of the experimental ewes were characterized by a faster growth rate, and they achieved significantly higher body weight (p ≤ 0.05) at 100 days of age. The lambs also had significantly higher parameters of MLD (p ≤ 0.05) at similar carcass fat content.

The paper presents the housing wall structure for the digital X-ray flat panel which can operate in extremely low temperature conditions. A technology of three-dimensional printing is proposed for making the detector housing with heat conductors incorporated in its wall structure.

The aim of this study was to evaluate the effects of a long-acting selenium (Se) preparation administered to sheep. The experiment was conducted on 30 dams and 36 lambs divided into three equal groups of 10 dams and 12 lambs each: Control—C, and two experimental groups—E (Se administered to pregnant ewes) and EI (Se administered directly to lambs after the colostral period). The Se preparation (Barium Selenate Injection, BVP Animal Care, 50 mg/mL) was administered by injection at 1 mL/50 kg (1 mg Se/kg) body weight (BW) to group E ewes in the third month of pregnancy (between 70 and 90 days) and to group EI lambs between 4 and 7 days of age. The following parameters were determined: Se concentration in the blood of ewes, milk yield, milk composition, Se concentration in milk, hematological, biochemical, and immunological parameters and Se concentration in the blood of lambs, growth rate and in vivo measurements of lean meat and fat content in lambs. Barium selenate significantly improved the Se status of dams and lambs, regardless of whether it was administered to pregnant ewes or directly to lambs in the first week of their life. The milk of ewes receiving the Se preparation was characterized by higher concentrations of fat and dry matter. The Se preparation induced significant changes in immunological parameters, thus enhancing defense mechanisms in lambs. The Se preparation exerted more stimulatory effects on humoral and cellular immune responses when administered directly to lambs after the colostral period (group EI) than to pregnant ewes (group E). The results of this study indicate that the long-acting Se preparation delivers benefits to sheep by boosting their immunity and, therefore, improving performance.

Introduction: In the Czech Republic, there is a deficiency of selenium in sheep due to its low level of occurrence in soil, thus in fodder. Selenium deficiency in these animals can manifest in a number of diseases. Therefore, sheep should be supplemented with preparations containing selenium with vitamin E, because Se is closely related to vitamin E, which plays an important role in the immune system. Aim: The aim of the study was to assess the selenium status of selected sheep breeds in the Czech Republic and to determine the effect of selenium and vitamin E supplementation on selected hematological, biochemical and enzymatic blood indicators and on reproductive indicators. Material and methods: The research material consisted of sheep, used in the Czech Republic, of three breeds: Šumavka (16), Valaszka (16) and Zwartbles (16). At the 3rd month of gestation, the sheep were injected with sodium selenate with vitamin E. In the blood of sheep, hematological, biochemical and enzymatic parameters were analized, and reproductive indicators of sheep were determined. Results and discussion: The concentration of Se in sheep was quite low at the beginning of the experiment (from 0.145 (AVR group) to 0.219 µmol/l (BZR group) and the highest concentration (1.322 µmol/l I BZR group) on the test III. It was shown in experimental groups that with increasing selenium concentration, GSH-Px activity increased from the lowest level of 53.77 (ASR group) to the highes: 222.88 U/gHb (BZR group). In sheep from experimental groups (ASR, AVR, BZR groups) better fertility was obtained, amounting to 96.3%, 95.5%,89.4%, respectively. Conclusions: In all groups of sheep there was a selenium deficiency. Supplementation turned out to be an effective method of compensating for its deficiency. The proper selenium status ensured better reproductive indicators for sheep.

The objective of this study was to determine the effect of dietary supplementation with β-hydroxy-β-methylbutyric acid (HMB) on live weight loss and selected blood parameters in goat kids after transportation to the slaughterhouse. The study was performed with goat kids that were weaned at 30 days of age and divided into two groups (GK): a control group and an experimental group whose diet was supplemented with HMB (at 50 mg kg−1 of BW) for 60 consecutive days. At the end of the 90-day rearing period, the animals were fasted for 12 h (with access to water) and were transported to the slaughterhouse in the following morning. Blood for analysis was sampled before transportation (BST1) and after unloading in the slaughterhouse (BST2). The animals were weighed on the same dates to determine live weight loss. Red blood cell counts (RBC), white blood cell counts (WBC), hemoglobin concentration (HGB), hematocrit (HCT), neutrophil to lymphocyte (N:L) ratio, and cortisol and glucose concentrations were determined in the sampled blood. The experimental goat kids were characterized by lower weight loss after transportation. Group of kids and BST did not induce variations in RBC, WBC, HGB, and HCT. Cortisol concentration was affected by both GK and BST. Cortisol levels increased after transportation in both groups, but this parameter was significantly higher in the control than in experimental animals at BST2. Glucose levels and the N:L ratio did not differ significantly between GK, but glucose concentration and the N:L ratio were higher at BST2 than at BST1 in both groups. The experimental goat kids were characterized by lower weight loss and lower cortisol concentration after transportation, which could point to the efficacy of HMB in boosting immunity and alleviating transportation stress in goat kids.

Background A healthy immune system plays a particularly important role in newborns, including in calves that are far more susceptible to infections (viral, bacterial and other) than adult individuals. Therefore, the present study aimed to evaluate the influence of HMB on the chemotactic activity (MIGRATEST® kit), phagocytic activity (PHAGOTEST® kit) and oxidative burst (BURSTTEST® kit) of monocytes and granulocytes in the peripheral blood of calves by flow cytometry. Results An analysis of granulocyte and monocyte chemotactic activity and phagocytic activity revealed significantly higher levels of phagocytic activity in calves administered HMB than in the control group, expressed in terms of the percentage of phagocytising cells and mean fluorescence intensity (MFI). HMB also had a positive effect on the oxidative metabolism of monocytes and granulocytes stimulated with PMA (4-phorbol-12-β-myristate-13-acetate) and Escherichia coli bacteria, expressed as MFI values and the percentage of oxidative metabolism. Conclusion HMB stimulates non-specific cell-mediated immunity, which is a very important consideration in newborn calves that are exposed to adverse environmental factors in the first weeks of their life. The supplementation of animal diets with HMB for both preventive and therapeutic purposes can also reduce the use of antibiotics in animal production.

Background The objective of this study was to evaluate the effect of HMB on the chemotactic activity, phagocytic activity and respiratory metabolism of peripheral blood granulocytes and monocytes in calves.Method The experiment was performed on 14 calves aged 30±2 days, divided into two equal groups of control (group I) and experimental (group II) animals. The feed administered to experimental group calves was supplemented with HMB (Metabolic Technologies Inc. Ames, IA, USA) at 40 mg/kg BW, whereas control calves were administered standard farm-made feed without supplementation. Blood was sampled from the jugular vein immediately before the experiment (day 0) and on experimental days 15, 30 and 60 to determine: chemotactic activity (MIGRATEST® kit), phagocytic activity (PHAGOTEST® kit) and respiratory metabolism (BURSTTEST® kit) of peripheral blood granulocytes and monocytes by flow cytometry.Results An analysis of granulocyte and monocyte chemotactic activity and phagocytic activity revealed significantly higher levels of phagocytic activity in calves administered HMB than in the control group, expressed in terms of the percentage of phagocytising cells and mean fluorescence intensity (MFI). HMB also had a positive effect on the oxidative metabolism of both granulocytes and monocytes after stimulation with Escherichia coli bacteria and with PMA (4-phorbol-12-β-myristate-13-acetate), expressed in terms of the percentage of oxidative metabolism and MFI.Conclusion HMB stimulates non-specific cell-mediated immunity, which is a very important consideration in newborn calves that are exposed to adverse environmental factors in the first weeks of their life. The supplementation of animal diets with HMB for both preventive and therapeutic purposes can also reduce the use of antibiotics in animal production.

Introduction Food manufacturers compete on the market, introducing innovative products. Functional products, which show a beneficial impact on human health over the one which comes from the basic product component, are becoming increasingly important. Since a few years researchers underline a huge importance of colostrum in this trade. ‘First milk’ is significantly richer in biologically active peptides, immunologic components and growth factors than later milk. Aim In the article an overview of literature concerning the meaning of bovine colostrum in human nutrition and its therapeutic properties was performed. Discussion A vast research which was conducted on animals, as well as in strict laboratory conditions (in vitro, in vivo) confirm clinical benefits of colostrum. A number of analyses is still conducted, which additionally refer to the design of the appropriate dose and time of treatment with colostrum. Colostrum is considered a fully safe substance. To this moment, even with very high doses, very few side effects were noted. The main functions of the colostrum are supplying the organism with essential nutrients which strengthen the immune system, stimulation of the immune system response, maintaining the intestinal microflora and tissue regeneration acceleration. Conclusions Summing up, further use of products based on colostrum both in healthy individuals – prevention, as well as with some diseases is justified. The interest in questioned substance is rising due to vast scientific and clinical research underlining the significance of colostrum in feeding of human beings. Scientists predict that products based on colostrum may play a significant role on the functional products market in the future.

The objective of the study was to investigate the influence of pre-milking teat disinfection on total bacterial contamination of teat skin, and to analyze the effect of pre- and post-milking teat disinfection on somatic cell count in milk. Three groups of cows in five dairy farms were used. The total bacterial contamination on cow teat skin before and after teat disinfection was determined. The number of colony forming units (cfu) was calculated per 1 ml a total for 2700 samples. The most bacteria on teat skin were effectively reduced after pre-milking teats disinfectionm almost in all groups of 5 farms (from 1.1 to 4.5 times). Summarized results showed that the number of bacteria counted on teat skin and milk somatic cell count (SCC) were significantly higher from teats with no pre- and post-milking teat disinfection in comparison with teats with pre- and post-milking teat disinfection or no pre-milking teat disinfection and post-milking teat disinfection only (p≤0.05). Pre-milking teat disinfectant with peracetic acid and hydrogen peroxide was effective in reducing total bacterial contamination on cow teat skin. The results also indicate that application with pre- and post-milking teat disinfectants provided an impact on the reduction of SCC in milk. The lowest iodine content was 0.1291 mg L-1 (group T1, whereas the highest was 0.2963 mg L-1). In our research the differences in the iodine content between farms were noted as well. For example, the highest iodine content in milk appeared at FIV farm. Statistical differences appeared at p≤0.05.

Highlights • Transition milk supplementation with colostrum improves calves growth. • Extending colostrum feeding period positively affected multiple blood variables. • Supplemented calves had lower disease incidence., The aim of this study was to determine the effect of colostrum-supplemented transition milk on the growth rate of newborn calves. Thirty-six day-old female Holstein calves with a birth weight of 43.4 ± 5.5 kg were randomly assigned to a treatment group and a control group. On day 1, all calves received one portion (3 kg) of colostrum within 2 h after birth. Between the second feeding and the age of 5 days, control calves received only transition milk that had been collected from dams shortly before feeding, and the treatment group received 1.5 kg of colostrum collected from dams on day 1 and 1.5 kg of transition milk from subsequent milkings. Monthly body weight and average daily gain were used to measure growth performance. Blood samples were collected from the jugular vein at multiple time points to evaluate the biochemical and immune status of calves. Colostrum-supplemented transition milk increased the concentrations of serum immunoglobulins, triacylglycerols, cholesterol and total protein. The activity of lactate-dehydrogenase and ceruloplasmin decreased, whereas lysozyme activity increased with time in the control group. It can be concluded that additional five days of colostrum feeding positively influences non-specific humoral immunity indicators and serum biochemical parameters in dairy calves.

Bioinformatics and cheminformatics tools such as databases play an increasingly important role in modern science. They are commonly used in biological and medical sciences and they have many applications in food science. Databases listing biologically active compounds contribute to the design of functional foods and nutraceuticals. Databases of toxic or allergenic compounds are useful for food safety evaluations. This review presents examples of freely available databases (without obligatory registration) listing major groups of bioactive components. The main categories of compounds annotated in online databases include nucleic acids, proteins, peptides, carbohydrates, lipids, and low-molecular-weight compounds. Other categories of database entries are also discussed, including enzymes, allergens and their epitopes, flavor-enhancing compounds, as well as toxic substances. The last section of the review focuses on metabases, which are Web sites that create access to multiple databases.

Introduction Composition and hygienic quality of milk determine its nutritional value and processing suitability. However, biological quality of milk depends on the content of bioactive components, which due to its health promoting properties have a positive effect on human health. Biologically active substances present in cow's milk include proteins, peptides, amino acids, sugars, vitamins, enzymes, sterols, phospholipids and fatty acids. Among these components, several proteins (lactoferrin, β -lactoglobulin, bovine serum albumin and casein) that inhibit cancer cell growth, deserve special attention. However, cow's milk contains also approximately 30 potentially allergenic proteins. The most common bovine milk allergens are casein fractions and β -lactoglobulin naturally not present in human breast milk. Aim The aim of this study was to analyze the available literature on the characteristics of cow's milk proteins as allergens that may cause food allergies and identify methods of reducing their immunogenicity. Material and methods On the basis of the available literature characteristics of cow's milk proteins and their effect on the occurrence of food allergy in human are presented. A review of the available methods of modification of animal proteins that may reduce its allergenicity was also conducted. Discussion It is possible to reduce cow's milk allergenicity in the production of dairy products by thermal, enzymatic and biotechnological techniques. The majority of subjects that demonstrate intolerance of bovine milk may safely consume fermented dairy products. Conclusions Prevalence of food allergy is so high that it may be considered a disease of civilization. Therefore, attention should be paid to food technological processes that may eliminate or reduce allergenicity of cow's milk proteins.

The objective of this study was to determine the effects of beef cattle breed and muscle type on the proximate chemical composition and quality traits of meat, including processing suitability. The experimental materials comprised samples of musculus longissimus dorsi (LD muscle) and musculus semitendinosus (ST muscle) collected from the carcasses of young Limousin, Charolais and Hereford bulls. The chemical composition, texture, hydration and color parameters of LD and ST muscles were determined. Meat from Limousin and Charolais bulls, characterized by higher body mass at slaughter contained more protein than meat from Hereford bulls. Meat from Hereford bulls had a higher fat content, compared with the other two breeds. Texture parameters, including hardness, gumminess and chewiness, varied depending on muscle type and cattle breed. An analysis of the maximum shear force values showed that the mechanical properties of beef also varied depending on cattle breed and muscle type.

Introduction Recent years have witnessed a growing interest in the nutritional value and health benefits of food products of animal origin. Numerous research studies have been undertaken to evaluate the effects of bovine milk, a key dietary component, on human health. Fat is one of the most important components in bovine milk, and its content ranges from 2.8% to 8.1%, subject to the breed of cattle, nutritional aspects, individual characteristics, lactation period, milk production hygiene and season. Aim The aim of this study was to review the latest literature concerning the health effects of components found in bovine milk fat. Materials and methods This paper is a literature review, and it analyzes the composition of bovine milk fat and its effects on human health. The available sources were grouped thematically, and an attempt was made to characterize various milk fat components and their effects on human health. Discussion The unique nutritional value of bovine milk can be attributed to the presence of short-chain fatty acids and medium-chain fatty acids which are important sources of energy for the muscles, heart, liver, kidneys, blood platelets and nervous system. They do not pose an obesity risk; they prevent ulcerative colitis, cancer, atherosclerosis and hypertension; they have anti-inflammatory and antibacterial effects, and they boost natural immunity. Milk contains cholesterol, a lipid derivative which stabilizes and stiffens cell membranes, builds the cell cytoskeleton, protects nerve fibers and acts as a precursor of steroid hormones, bile acids and vitamin D 3 . Bovine milk lipids do not exert hypercholesterolemic or atherogenic effects in the human body. Conclusions A growing tendency to replace animal fats, mainly milk fat, with vegetable fats is a matter of concern.

Introduction Civilization-related diseases are defined as diseases encompassing a global range, whose appearance or spreading issues have been largely caused as a result of the advances of modern civilization. Thus, such diseases are also interchangeably termed diseases of the 21st century. Allergy, i.e., an organism's abnormal immune reaction to exposure to an allergen, due to its increasing incidence, especially in developing countries, is occasionally called “an epidemic of the 21st century”. Issues concerning food allergy are significant ones with respect to allergies as such. Aim This work aimed at reviewing the most current literature concerning food allergy. Discussion The incidence of adverse reactions to food varies. Reaction depends on the allergen type, patient's age, type of evaluated mechanism, and local diet. Potentially, each food may cause sensitivity; however, in order for a reaction to occur several conditions must be fulfilled. Allergens are mainly water-soluble glycoproteins ranging in size from 10 kDa to 70 kDa. Cases of allergies caused by smaller particles (approx. 3 kDa) or larger ones (up to 100 kDa) are also known. The increased prevalence of food allergies results from an unfavorable combination of genetic and environmental factors. Conclusions The incidence of food allergies is on the increase. The symptoms are intensified and regress at more advanced ages, whereas diagnostic and treatment complexities place these diseases among civilization-related diseases of the present century.

The objective of this study was to evaluate the effect of HMB on selected parameters of the humoral immunity in calves. The experiment was performed on 14 calves aged 30 ± 2 days, divided into two equal groups of control (group K) and experimental (group H) animals. The feed administered to the experimental calves was supplemented with HMB at 40 mg/kg BW, whereas the control calves were administered standard farm-made feed without supplementation. Blood was sampled from the jugular vein immediately before the experiment (day 0) and on experimental days 15, 30 and 60 to determine the following immunological parameters: total protein levels, gammaglobulin levels, lysozyme activity and ceruloplasmin activity. An analysis of the results obtained revealed a significant increase (p < 0.05; p < 0.01; p < 0.001 respectively) in gammaglobulin levels and lysozyme activity throughout the entire experimental period, an increase (p < 0.05; p < 0.01 respectively) in ceruloplasmin activity on experimental days 15 and 30, but no changes in serum total protein levels of calves administered HMB as compared to those found in the control group

Locomotor activity and daily milk yield of dairy cows during the perioestrous period in successive lactationsThe experiment was conducted in a herd of high-producing Holstein-Friesian cows, using the AfiFarm Herd Management Software, to analyze their locomotor activity during 236 oestruses in relation to the daily milk yield determined during the periooestrous period in four successive production and reproductive cycles. Day "0" was the day of the observed oestrus. Locomotor activity and milk production levels were monitored five days before and five days after oestrus. A correlation was noted between high milk yield and the reproductive performance of cows. An increase in milk yield was accompanied by extended inter-pregnancy and inter-calving intervals and a drop in the insemination index which also tended to decrease in multiparous cows. Primiparous and the highest-yielding cows were characterized by the highest levels of locomotor activity. The physical activity of cows increased by around 67% during oestrus. However, daily milk yield declined at oestrus, compared with the average milk production levels determined five days before and five days after oestrus in each lactation. The installation of pedometers supported the detection of oestrus, including silent oestrus, in dairy cows, and the AfiFarm system was found to be an effective tool for dairy farming and herd management.

The milk yield of 24 934 cows from herds monitored by the National Animal Breeding Center, Branch in Olsztyn, was analyzed. The data were collected in the years 1997–2006. The cows were divided into three groups, based on herd size: group I of up to 20 cows, group II of 21–50 cows and group III of more than 50 cows. Additional criteria for the above division were the number of successive 305-day lactations and full lactations as well as the length of inter-calving intervals. The objective of this study was to determine the effect of herd size on the yield and proximate composition of milk in active cattle populations in farms in north-eastern Poland over a ten-year period, taking into account lactations of normal length and full lactations, inter-calving interval (ICI) duration and lifetime cow productivity. The average yield over 305-day lactations was 6579 kg milk (6723 kg FCM), 273 kg fat (4.15%), 213 kg protein (3.24%), 309 kg lactose (4.70%) and 841 kg dry matter (12.78%). Cows in the largest herds (> 50 head) were characterized by the highest productivity, and cows in the smallest herds (≤ 20 head) – by the lowest. The latter produced milk with the highest fat content (4.16%) and the lowest protein content (3.21%). In herds comprising more than 50 animals, cows with the longest ICI (> 525 days) were marked by the highest milk production in full lactations (11 010 kg). As regards lifetime productivity, the highest values were noted in cows used for 3.44 years in the smallest herds (19 809 kg milk). In the largest herds cows were used for the shortest period of time (3.31 years), and their lifetime productivity reached 17 185 kg milk.

The study was conducted in the years 2006–2008. The experimental materials comprised 368 Holstein-Friesian cows purchased from Germany as in-calf heifers. The objective of this study was to determine the health status of cows in a commercial herd kept in the Olsztyn region, based on the type and incidence of diseases that occurred during three consecutive lactations, and to analyze the effect of these diseases on milk yield and composition in the first, second and third lactation cycle. The cows were divided into five groups: HEA – clinically healthy cows (showing no disease symptoms), MAS – cows with mastitis, LAM – cows with foot/leg defects and lameness, REP – cows with reproductive problems (retention of the placenta, endometritis, ovarian cysts), MET – cows with metabolic diseases (ketosis, abomasal displacement). It was found that the most common diseases during three consecutive lactations in the investigated herd were endometritis (37.63%) which occurred soon after calving (on day 18 post-partum), mastitis (35.48%), formation of ovarian cysts (10.10%), ketosis (8.39%) and leg/foot defects (6.44%). Retention of the placenta and abomasal displacement were diagnosed much less frequently (1.62% and 0.34% respectively). The percentage of healthy cows decreased in successive lactations (19.81% in the first lactation, 12.28% in the second lactation, 6.22% in the third lactation). During each lactation, more than one third of cows suffered from mastitis. The proportion of cows showing the symptoms of ketosis increased with age, from 5.12% in the first lactation to 12.23% in the third lactation. The highest yields of milk and milk components over a 305-day lactation cycle were noted in cows with reproductive diseases (ROZ). Foot/led defects and lameness (LAM), mastitis (MAS) and metabolic diseases (MET) had the most significant effect on a decrease in milk production.

The experiment was performed in the years 1998-2000 on two farms located near to Vistula Lowlands. The experimental materials were comprised of 52 daughters of bull Paran, among which 21 possessed the mLys-mic 7 allele and 31 - the mLys-mic 3 allele. The serum and whey bacteriolytic activity of the lysozyme, concentrations of selected mineral elements, technological properties of milk at successive the first lactation stages (30, 100, 150 and 200 days), somatic cell count and bacterial count were investigated in this study. The results obtained indicate that Lys-mic polymorphism has low suitability as a marker for milk production capacity in cows. The lysozyme gene, treated as a mastitis resistance factor, showed no effects on somatic cell count and bacterial count. Further investigations, conducted not only during the first lactation, but also during the next lactation in a herd threatened by a variety of pathogenic factors, would be carried to validate this Lys-mic gene polymorphism on mastitis resistance.

In this study two analytical methods, one based on matrix solid phase dispersion (MSPD) and the other on liquid–solid extraction (LSE), coupled with gas chromatography, were evaluated and used to determine the presence of 163 pesticides (6 acaricides, 62 fungicides, 18 herbicides and 77 insecticides) in various herbs. Both methods were optimized considering different parameters (sample to sorbent mass ratio, extracting solvent, sorbents for clean-up step, etc.). The results of these validated sample preparation procedures were compared. Under optimum conditions, the mean recoveries obtained were in the range of 70–119 % for MSPD for most pesticides and 70–118 % for LSE, but with several exceptions. Precision values, expressed as relative standard deviation (RSD), were ≤16 % for MSPD and

The human diet should be a rich source of nutrients, energy and tissue-building materials. Bovine milk is one of the few food products of animal origin that meet the above requirements. It contains proteins rich in readily available amino acids, fatty acids, vitamins, micronutrients and macronutrients, such as calcium, magnesium, phosphorus, sodium, iodine, potassium, chlorine and small quantities of iron. This study discusses the positive effects of bovine milk on human health, resulting from its composition and high nutritive value. We have reviewed numerous publications and reports indicating that milk contains readily available amino acids, unsaturated fatty acids which are vital components of the human diet, as well as macronutrients and micronutrients that regulate biochemical processes in the body. Particular attention has been paid to the anti-carcinogenic, antioxidant, anti-sclerotic, anti-inflammatory and antibacterial properties of milk, which is also known to lower blood pressure and strengthen the immune system. The health benefits delivered by selected minerals contained in milk are also described. Calcium content largely determines the nutritional value and heat stability of milk, as well as its suitability for cheese production. Milk calcium is easily absorbed, and it is characterized by a high level of physiological activity due to a favorable calcium to phosphorus ratio of 1.2:1. Milk contains 0.75 g-1.10 g dm–3 of phosphorus, and phosphorus concentrations are generally stable and independent of the nutritional regime of cows. The magnesium content of milk is determined in the range of 100 to 150 mg dm –3 . In milk, magnesium is found in the form of soluble compounds (75% of total Mg) as well as colloidal compounds (phosphates, citrates). Magnesium concentrations are correlated with the calcium content of milk. The magnesium to calcium ratio determine milk’s heat stability. Milk contains 1.35 to 1.55 g dm–3 of fully ionized potassium. The sodium content of milk is

Contemporary human diet contains excessive quantities of n-6 saturated fatty acids (SFA) and polyunsaturated fatty acids (PUFA), but it is deficient in n-3 fatty acids. This imbalance could be the cause of respiratory diseases, obesity and cancer. Until recently, animal fat, including meat fat, was regarded solely as a source of saturated fatty acids, which are a risk factor for atherosclerosis, obesity and certain types of cancer. Recent studies have shown, however, that animal fats contain biologically active substances beneficial for health, and that only some saturated fatty acids have adverse consequences. The latter group includes lauric acid (C12), myristic acid (C14) and palmitic acid (C16), i.e. mainly the ones with an unfavorable n-6/n-3 fatty acid ratio. Apart from fat, beef also contains high amounts of minerals, mainly phosphorus, potassium, magnesium and zinc. Conjugated linoleic acid (CLA), in particular its cis-9 trans-11 and trans-9 cis-11 isomers, is one of the substances with health-supporting properties. Synthesized solely in the gastrointestinal tract of ruminants, CLA reaches the blood stream and is used by the mammary gland to synthesize milk fat. CLA is embedded in the animal’s adipose tissue. There is a large body of research confirming CLA’s ability to reduce the risk of atherosclerosis and obesity, and to lower cholesterol levels. When incorporated into the human diet in the amount of 1.5 to 3.5 g, CLA exerts anticarcinogenic effects (it inhibits the development of breast cancer, malignant melanoma, colorectal cancer and lung cancer). CLA prevents

Massive deaths were reported on a chinchilla ( Chinchilla lanigera) farm, which over 10 months led to the elimination of the herd. After three months of feeding, longitudinal precipitates inside the pellets were noted. The first symptoms were observed two weeks after the introduction of feed, and included lethargy, decreased mobility, and reduced appetite, as well as increased reactions to external stimuli. Over time, single deaths, hair loss and gnawing, white discolorations on teeth, and polyuria were reported. Haemorrhages of the reproductive tract and mass abortions were observed. Necropsy revealed the presence of transudate with pH = 10, severe hyperae - mia of the intestinal mesentery, and extensive regressive lesions in the gastric and intestinal mucosa. Both grossly and microscopically, lesions were noted in the liver, kidneys, adrenal glands, and lungs. The urinary bladder was overfilled. No lesions were observed in the spleen or mesenteric lymph nodes. Histopathology of skin specimens revealed atrophy of the hair follicles. Diagnosis was sodium carbonate intoxication. Owing to the specific features of this species, it was impossible to introduce emetic-based treatment in order to eliminate the toxic agent from the body. No therapeutic measures were undertaken because of the late diagnosis of the toxic agent and late removal of feed, as well as extensive lesions on the gastrointestinal mucosa.

The experiment was performed on 121 primiparous Polish Holstein-Friesian (PHF) cows and 36 primiparous Jersey (JER) cows. The highest decrease in casein yield was noted in JER cows at 7.36 % on day 90 of lactation, 15.95 % on day 150, 26.78 % on day 210, 37.01 % on day 270 and 39.67 % on day 330. In PHF cows this decrease was substantially lower, at 4.98 %, 7.65 %, 8.72 %, 10.50 % and 16.19 % respectively. The casein content of milk from primiparous PHF cows ranged from 2.38 % (LGB – day 60) to 3.09 % (LGB BB – day 330), and it was found to be considerably lower in JER cows, varying between 2.35 % (CSN3 BB – day 30) and 3.61 % (CSN3 BB – day 210). The highest casein yield was recorded in PHF cows with the following genotypes: LGB AA (day 60), CSN1S1 BB (day 60), CSN2 AB (day 270), CSN3 BB (day 150). In JER cows the highest casein yield was noted on day 90 of lactation with respect to the following genotypes: LGB BB, CSN1S1 BC, CSN2 AA and CSN3 BB. In PHF cows the greatest effect on whey protein yield was exerted by the following genotypes: LGB AA (day 90), CSN1S1 BC (day 60), CSN2 AA (day 90); the CSN3 BB genotype influenced whey protein yield in cattle of both breeds (day 90). In JER cows the highest daily yield of whey proteins was observed on day 90 of lactation, with regard to the following genotypes: LGB BB, CSN1S1 BC, CSN2 AB and CSN3 BB.