Influence of bovine follicular fluid on thawed bovine spermatozoa - assessment by CASA system and flow cytometry.

AIM: The aim of this study was to analyze the effect of bovine follicular fluid on the survival, morphology and kinetic parameters of bovine thawed spermatozoa under laboratory conditions. MATERIALS AND METHODS: The semen from 5 bulls of proven fertility was incubated in follicular and physiological fluid for 8 hours. During this time assessment using the CASA system was performed. At the beginning and the end of incubation process evaluation by flow cytometry was conducted. RESULTS: The results of the sperm motility assessment showed a significant decrease in the analyzed parameters both in the follicular and physiological fluid. A significant reduction in all parameters characterizing movement properties in the semen incubated in the follicular fluid was found. In the physiological fluid, a similar trend was demonstrated only for the following properties: VAP, VSL, VCL, ALH, BCF. A significant difference was found for both fluids in: VCL (p=0.026), ALH (p=0.038) and LIN (p⟨0.001) at the beginning of incubation. The results of the plasma membrane integrity assessment showed a statistically significant increase in the percentage of dying sperm at the 8th hour of the incubation in the follicular fluid. In the case of semen incubation in physiological fluid, a statistically significant decrease in the percentage of live non-damaged cells was found with a simultaneous increase in the subpopulation of undamaged dead cells. CONCLUSIONS: Follicular fluid rapidly accelerates the capacitation process. The results of flow cytometry support the hypothesis concerning the ability of follicular fluid to prolong sperm survival.

Evaluation of Acute Phase Proteins in Clinically Healthy Dairy Cows in Perinatal Period and During Lactation.

The estimation of acute phase proteins (APP), which are recognized as inflammation markers is a good method for animal health monitoring. Several factors such as obesity, age and sex are also known to modulate APP status. We evaluated the influence of pregnancy and lactation in 65 clinically healthy dairy Holstein-Friesian dairy cows, 2nd÷4th lactation, chosen from 3 different dairy farms located in South West part of Poland. Bovine C-reactive protein (CRP), haptoglobin and fibrinogen were assayed using commercial ELISA kits. The highest values of CRP and haptoglobin were observed in cows during the first month after calving. The highest concentrations of fibrinogen was found in a group of cows prior to expected date of parturition and the level of this protein in blood plasma was decreasing during lactation. The significant differences of analyzed APPs among cows before delivery, during first month after calving and in lactation (1-3 months after delivery) suggested that factors like pregnancy and stage of lactation would have an influence on their concentration.

The investigation of correlation among selected biochemical parameters and vital signs in dairy herd to design the bio-cybernetic dairy cow model.

The paper presents investigations of the relationship between the biochemical parameters and vital signs in dairy cows. We analyzed the welfare and functioning of a dairy herd using biochemical parameters and vital signs. Life and biochemical parameters were examined. In the model indicators useful for monitoring the herd are: the age of the cows, the number of cows' lactating, daily amount of received milk, length of lactation period for cows in the herd, the length of inter-calving period for cows, the number of days to effective insemination, the amount of protein in the feed, the level of ß-oxidation in leucocytes, glucose transport through red blood cells and plasma insulin. Based on the results the mathematical model was designed allowing the presentation of a cybernetic model of cow's organism. There was constructed a multi-equation model which determined the relationships between the selected variables describing the state of dairy cows in the herd and variables that characterize their welfare with its statistical verification.

The influence of antibiotic treatment of bitches in oestrus on their attractiveness to males during mating.

The aim of this study was to evaluate the influence of the antibiotic treatment, including the mode of drugs administration, on bitches' attractiveness to the stud dogs during mating. Moreover, we tried to estimate the possibility of aversive effect of the drug vehicle on the male behavior. In experiment I, four bitches in oestrus without antibiotic treatment (group A), four bitches treated with intravaginal antibiotic (group B) and four bitches treated with intramuscular antibiotic (group C) were presented to four stud dogs. In experiment II, bitches in oestrus (n = 5) were presented to the males (n = 2) before and after the application to the females' vulva the antibiotic carrier--Miglyol 840 (Sasol, Germany). In both experiments the presence of the typical sexual behavior of the males (sniffing, licking the vulva and anal region, mating attempts) was evaluated. In experiment III the reaction of the males to the samples containing oestrual discharge from the bitches untreated and treated with antibiotics was evaluated. In the last part of study the aversion reaction to the samples containing antibiotic and the antibiotic carrier was evaluated. The results of experiments showed that females treated with the antibiotics were less attractive to males than untreated females, regardless of the method of administration. We did not observe adverse effect of the antibiotic carrier but samples from the bitches treated with antibiotics were significantly less attractive to the males. We concluded that the reason for reduced attractiveness of the bitches in oestrus after antibiotic treatment was the changes in semiochemical signal emitted by treated females as a consequence of elimination of the vaginal bacterial flora, which seems to be involved in creation of the typical, recognizable by the stud dogs, oestrual signal but also by the possible covering effect of used drugs.

The effect of MgSO4 addition and the increasing doses of calcium and phosphorus during ending drying period on the occurrence of hypocalcaemia and hypophosphataemia in dairy cows.

The aim of the presented study was the estimation of optimal Ca and P levels applied before calving together with anionic salt addition, as an element of hypocalcaemia and hypophosphataemia prevention. The experiment was carried out during the dry period on 48 cows with similar milk yield in the previous lactation. Cows were divided into four groups. In group I (control) the amount of minerals was in accordance to NRC standards. In experimental groups (groups II-IV), two weeks before calving, cows received 140 g/day/head of hydrated magnesium sulphate to achieve dietary cation-anion difference at the level of about 50 mEq/kg DM. In groups II and III cows received calcium carbonate (100 g/day) 10 days a.p. (antepartum) (group II), or 5 days a.p. (group III), while cows in IV group received dicalcium phosphate (100 g/day) for 5 days a.p. Application of MgSO4 x 7H20 significantly affected the urine pH of cows from group III and IV 4-5 d. before calving - 6.45 and 6.81, respectively. The acidification of urine was observed after calving in group IV (7.13). In cows from group II (100 CaCO3 10 days a.p.) urine pH decline was not found (7.97-7.75). In that group the incidences of hypophosphatemia were noted (blood serum inorganic P level 1.41-1.46 mmol/1). Addition of magnesium sulphate prevented hypocalcaemia occurrence -- 4-5 d. before calving the concentration of ionized Ca in blood serum was 1.11, 1.13 and 1.16 mmol/1 (respectively for group II, III and IV). Reproductive functions were significantly improved after the application of CaCO3 and CaHPO4 for 5 days a.p. in comparison with control and group II -- progesterone concentration in the blood serum on the 45th day of lactation was 1.396 - 1.409 versus 0.799 - 0.401. The correlation between progesterone and inorganic P level in serum was almost significant. Based on the obtained results a treatment optimal in prevention of hypocalcaemia and hypophosphataemia is the application of 50 g CaCO3 and 50 g of CaHPO4 for the last 5 days of the dry period together with MgSO4 x 7H20 given for 14 days a.p.

The influence of administration of biotin and zinc chelate (Zn-methionine) to cows in the first and second trimester of lactation on their health and productivity.

In cattle, the prevention of diseases might be possible using dietary methods, with nutritional optimization of feed rations. For years significant influence has been associated with the addition of biotin, methionine and zinc (each given individually, or as chelate - Zn-methionine). The aim of this study was to evaluate the influence of biotin or biotin + Zn-methionine additives on the health and performance of cows, in the first and second trimester of lactation. This study was carried out in 3 groups of cows, 30 animals in each group. In the first group cows were fed the usual fodder used on the farm. In the second group biotin at 10 mg/day/cow was added. In the third group both biotin at 10 mg/day/cow and Zn-methionine at 5 g/day/cow were added. The administration of biotin increased the milk yield and reduced the occurrence of retained placenta, as well as endometritis puerperalis. However, the high doses of biotin suppressed ovulation and oestrus symptoms in the investigated cows (low progesterone levels on days 15, 21 and 45 after calving). Zn-methionine in comparison to biotin had a lower effect on the milk yield in the cows. Moreover, its supplementation improved the milk content, as well as some of the blood parameters; it also decreased the number of somatic cells in milk. The concurrent administration of biotin and zinc-methionine seemed to be a good method for the prophylaxis of subacute mastitis and for the improvement of the high yielding dairy cows' productivity.

Curli expression by Escherichia coli strains isolated from bovine mastitis.

The aim of the study was to determine the expression of mannose-sensitive and mannose-resistant adhesins by agglutination of cattle, sheep, goat, rabbit, horse, and chicken red blood cell assay, and curli fimbriae by Congo red binding assay among 341 E. coli strains isolated from 51 milk samples of clinically recognized bovine mastitis. Curli fimbriae expression within biofilms created on an inert surface was also investigated. To determine whether curli fimbriae are expressed both in conditions optimal for their production and in conditions resembling the host organism, the study was conducted in anaerobic atmosphere at 37 degrees C, and at room temperature in aerobic atmosphere. The results demonstrated that although the E. coli isolates examined were deprived of mannose-sensitive and mannose-resistant adhesins they were able to produce curli fimbriae in both aerobic and anaerobic conditions at room and higher temperature, indicating that these adhesins may be involved in the pathogenesis of bovine mastitis.

Importance of newly detected staphylococcal enterotoxins for food safety.

Staphylococcal enterotoxins (SEs) are emetic toxins causing food poisoning in humans, because of their biological activity and structural relatedness They have been classified as members of the pyrogenic exotoxin superantigen family Among them nine major antigenic types of emetic enterotoxins were recognized In recent years several newly detected SEs were also discriminated, but their occurrence and role in human and animal diseases are not fully understood Neverthless, evidences of their pathogenic role and broad distribution in staphylococcal strains cumulate Therefore their importance as potential risk factor for food safety becomes essential For this reason their properties, genetic determinants and supposed mechanisms of the pathogenic activity are discussed in respect of their potential hazard to human health.

Thyroid hormones (TH) and 5'-monodeiodinase (5'-MD) activity in goat's milk from the early, mid- and late lactation period.

The physiological significance of thyroid hormones (TH) present in colostrum and milk is still under consideration. The present study was aimed at determining milk thyroxine (T4) and triiodothyronine (T3) levels in three lactation phases (early, mid- and late) of the goat, and to measure activity of the milk 5'-deiodinase (5'-MD) enzyme responsible for the intramammary conversion of prohormone T4 to its metabolically highly active form T3. Thirty-two milk goats (Polish White breed) fed a standard diet were used for milk sampling. The highest TH levels in mammary secretion were recorded during the first 2-3 days post partum. Then the hormone levels decreased, and by about Day 7 fluctuated around the overall mean for the early-lactation phase (Days 1 to 24 of lactation), recording 0.134+/-0.059 microg T4 and 150.8+/-2.80 ng T3 in 100 ml of the milk. Such T4 concentrations appeared to be comparable to those in the rabbit and human, whereas the concentration of T3 was higher than in the cow, pig and mare's milk. Milk 5'-MD activity was higher (P < 0.01) during early and late lactation, compared to the mid-lactation phase. It coincided with low T4 and high T3 milk levels during early lactation, and with high milk T4 and low T3 concentrations during late lactation. The quantity of T4 and T3 available to newborn kids in milk suggests that TH ingested with the colostrum may have a physiological role during the early postnatal life of suckling goats.

Thermal changes in cow's mammary gland after experimentally invoked inflammation (mastitis).

The purpose of the study was the evaluation of the thermal changes within mammary gland in cows, after experimentally invoked inflammation, developed as a result of 60 ml of 20% NaCl solution given directly into the udder (A and D quarters). Three hours after injection, the increased' temperature of teats and their bases by 2.26 degrees C and 0.58 degree C, respectively, was stated. The temperature was still increased after 6 hours from NaCl solution injection. It was accompanied by increase of heat flux from the skin surface by 50.17 mW/cm2 taken from the teat surface, and by increased values of Burton Index--the tissue blood supply index.

[The effect of technopathologically limited stress factors on the fertility of cattle]. / Einfluss technopathiebedingter Stressfaktoren auf die Fruchtbarkeit des Rindes.

The influence of purulent claw-diseases on the development of uterus infections, its involution and ovary dysfunctions (acyclia, cysts) was examined. It was shown that A. pyogenes, Ps. aeruginosa, Fus. necrophorum and other microorganisms involved in these lesions are potential sources for the infections of the uterus. In comparison with the controls the frequency of endometritis was twice in the group with claw-problems. Similar differences existed in the involution-time of the uterus or its atonia, acyclia and the development of ovarian cysts (p less than 0.01). The Index of insemination was elevated by about 65%.