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The hypothesis that relocation of cows with a housing change temporarily decreases their milk production and affects cows' behaviour in the milking parlour has been proved. Forty-one Holstein cows on the 1st and 2nd lactation were relocated from the tie-stall barn into the free-stall barn. Cows were milked in a 2 × 5 herringbone parlour twice a day. Individual milk yields, order, and used parlour side were recorded electronically during 50 (milk) or 22 (order and side) milking sessions. Milk yield after cows' relocation (23.76 kg) significantly decreased if compared to that reached on the day preceding relocation (30.97 kg; P < 0.001). Milk production approached the level of the last day on days 3 and 4 (30.72 and 30.72 kg, respectively) after relocation. Milk yield exceeded that before relocation on day 13 (31.82 kg). There were significant differences between parities during the whole observation period except for the first day after relocation - cows on the 2nd parity yielded more (P < 0.001). Multiparous cows entered the parlour earlier than primiparous, equally during morning and evening milkings (P < 0.01). Generally a left-side preference was found in the observed cows, while it was more prominent in primiparous than in multiparous cows during evening milkings (P < 0.05). Relationships between milking order and milk performance were on days 5-11 negative and significant (P < 0.01). We may conclude that although temporarily, relocation with housing and milking changes significantly affected the milk yield.

The objective of this investigation was to evaluate the stability of milk flow curves and the volume of residual milk in relation to milk flow curves in breeds Tsigai, Improved Valachian, and Lacaune (n = 16 heads per breed) milked twice daily. Milk flow type stability was evaluated at morning milking (stabile milkings) during three successive days in the middle of two months (June, July). After the following fourth morning milking (OT milkings) in both months, oxytocin was injected intravenously at a dose of 2 UI. Afterwards the ewes were milked again in order to remove residual milk. The milk flow curves were classified into four types: 1 peak (1P), 2 peaks (2P), plateau I (maximal milk flow over 0.4 l/min) (PLI), plateau II (maximal milk flow less than 0.4 l/min) (PLII). If all milk flow curves of one animal were of the same type within one month and within both months, respectively, the animal was characterized as the ewe with the stabile type of milk flow. Frequency of occurrence of single milk flow types (1P : 2P : PLI : PLII) during stabile milkings was 42 : 49 : 9 : 0% in June and 51 : 37.5 : 11.5 : 0% in July. 33 ewes (i.e. 69%) had the stabile type of milk flow within both months. But, more than 51% of them had 1P type of milk flow. Milk production varied according to milk flow curve during OT milkings (0.427 ± 0.015, 0.498 ± 0.024, and 0.655 ± 0.035 l for 1P, 2P, and PLI, respectively). The highest percentage of residual milk from total milk yield (RM/TMY) was observed in ewes with 1P (20.29 ± 0.85%), followed by ewes with PLI (12.31 ± 1.99%) and 2P (9.72 ± 1.36%) (P < 0.0001). Lacaune ewes had the lowest amount of residual milk (0.054 ± 0.006 l) and RM/TMY (9.86 ± 1.16%) compared to breeds Tsigai (0.088 ± 0.008 l; 16.47 ± 1.44%) and Improved Valachian (0.069 ± 0.010 l; 15.99 ± 1.78%) indicating their better udder emptying.

Studies that involved testing monoclonal antibodies (mAbs) for cross-species reactivity proved to be efficient for the identification of previously unrecognized antigens in a number of different species. Twenty-six mAbs specific to different bovine CD (cluster defined) antigens (CD9, CD18, CD45R, CD41/61, CD62L, MHC class I and bovine IgG light chain molecule) were assayed for reactivity with rabbit peripheral blood leukocytes. Four of the mAbs recognizing CD9 and CD41/61 were reactive with rabbit platelets or granulocytes. These were investigated further by immunoblotting and immunohistochemical staining. The study identified CD9 and CD41/61 molecules on rabbit cells by mAbs IVA-50 and IVA-38. It showed that IVA-50 is a new valuable CD9 reagent for rabbit immunology which could be used for immunofluorescence staining or ELISA assay, immunohistological and molecular studies of rabbit CD9 antigen. IVA-38 recognizes the CD41/61 on rabbit platelets in indirect immunofluorescence and ELISA assay.

The aim of this study was to evaluate the milkability of two purebred breeds Tsigai (TS, n = 14) and Improved Valachian (IV, n = 15), their crosses with Lacaune 50% TS × 50% LC (n = 13), 50% IV × 50% LC (n = 9) and purebred Lacaune (LC, n = 19). The measurements of the milk flow were performed on day 90 ± 10 of lactation during evening machine milking. The recording of milk flow was carried out by the equipment for graduated electronic recording of milk level in a jar in one-second intervals. The milk flow curves were classified into four types: 1 peak (1P), 2 peaks (2P), plateau I (maximal milk flow over 0.4 l/min (PLI)), plateau II (maximal milk flow less than 0.4 l/min (PLII)). The last two types refer to ewes with steady milk flow during milking. Udder morphology traits were measured (cisternal depth, teat angle) and subjectively assessed by the use of linear scores (cistern depth, teat position). The average total milk yield was 0.335 ± 0.043, 0.392 ± 0.042, 0.407 ± 0.042 l in purebred TS, IV, LC resp. and 0.397 ± 0.046, 0.434 ± 0.056 l in crosses TS × LC and IV × LC, resp. The frequency of occurrence of different types of milk flow /1P:2P:PLI:PLII/ was 27, 47, 22, 4%, resp. The highest milk yield was observed in ewes with PLI (0.481 ± 0.045 l), followed by 2P (0.401 ± 0.029 l) and 1P (0.293 ± 0.036 l) type of milk flow curve (P = 0.0112). An opposite effect was observed in the percentage of machine stripping yield where 1P had 41.94 ± 3.83%, 2P 21.29 ± 3.04% and PLI 15.90 ± 4.70% (P < 0.0001). LC and TS × LC, IV × LC had the more horizontal teat position than TS and IV. It can be supposed that at least during around 69% milkings the sheep released oxytocin in response to machine milking and that TS, IV and their crosses with LC also have a suitable potential for machine milking.

The aim of this study was to investigate milk flow patterns and milk composition in relation to pre-milking udder stimulation. The milk of one quarter of each of the sixteen cows was removed separately and in the course of milking it was divided into six fractions (P â cisternal milk during milking without stimulation and the first 300 ml during milking with pre-stimulation, 0-25%, 25-50%, 50-75%, 75-100%, 75-100%, MS-machine stripping) and into five portions (25%, 50%, 75%, 100%, 100% + MS). Two milkings were performed during two consecutive evening milkings with or without manual stimulation. Pre-stimulation resulted in a reduction of milking time, duration of the increase and decline phase of milk flow, stripping yield, but it increased the peak flow rate as compared to milking without pre-stimulation (P < 0.05). In both fractions and portions the content of fat increased steadily during milking and reached a maximum at MS. Lactose increased from P to 50-75% and then it decreased to MS. Significantly higher fat contents at 25% and 50% portions and in both protein and dry matter at 25% portions were found during milking with pre-stimulation as compared to no stimulation (P < 0.05). The content of fat, protein and dry matter were also higher in both P and 0-25% fractions for milking with pre-stimulation (P < 0.05). Pre-stimulation positively influenced the parameters of milk flow and therefore the efficiency of milk removal and contributed to better distribution of components in milk fractions during milking.

The release of oxytocin and milk ejection occurrence in response to teat stimulation are crucial for fast and complete milk removal during milking or suckling. The milk ejection reflex can be disturbed at central or peripheral level under different experimental and practical conditions. The central disturbance results in the lack or insufficient ejection of the alveolar milk into the cistern due to inhibited oxytocin release from pituitary into the blood circulation. The important role in the pathophysiological regulation of the inhibited release of oxytocin is played by an opioid system. Endogenous opioids have suppressive effects on oxytocin release under the normal conditions of milk removal. However under the conditions of disturbed milk ejection their role in dairy cows was not confirmed. Other possible mechanisms involved in the central inhibition of oxytocin release are discussed. In dairy cows as compared with rats the mechanisms involved in the regulation of oxytocin release at the central level remain unclear. The central inhibition of oxytocin release has often been observed in dairy practice during milking of primiparous cows after parturition, suckling by alien calf, calf removal before milking, milking of cows in the presence of own calf, relocation and milking in an unknown milking place. If sufficient released oxytocin cannot induce the transfer of milk from alveoli to cistern, peripheral mechanisms are involved. Peripheral mechanisms are related to the increased levels of catecholamines and/or activation sympathetic nervous system at the udder level. In conclusion, the release of oxytocin and milk ejection efficiency can be very easily suppressed by many factors. The effect of milking conditions on regulation of milk ejection has to be considered. Thus the physiological requirements of dairy cows have to be respected.

The aim of this trial was to clarify whether suckling after several weeks of only machine milking can affect the release of oxytocin, cortisol and prolactin in dairy cows. In total twelve Brown Swiss cows on their first to third lactation were used. Pre-experimental period: all cows were suckled three times daily (9.00, 14.00 and 20.00) and milked twice daily (7.00 and 17.30) in tie housing during the first 5 days postpartum. Afterwards the calves were separated and moved to another building. The cows were moved to loose housing and milked in the dairy parlour within the same stable. Experimental period: after four weeks of only machine milking twice daily, cows were relocated from the herd to the same place as they were housed and milked during their postpartum period. The cows were again suckled on day 3 and 4 after relocation at the same time as above. Oxytocin, cortisol and prolactin levels were evaluated during the first suckling on day 3 (9.00) and during suckling at the same time next day (4th suckling) after relocation. Oxytocin secretion was clearly inhibited in all cows during the first five minutes of suckling with tendency of slow increase during the next minutes of suckling (suckling lasted about 10 min) except for two primiparous cows showing an increase of oxytocin release from the first minute of suckling. The release of oxytocin in response to the 4th suckling significantly increased immediately after start of suckling. Both, cortisol and prolactin significantly increased in response to all sucklings. There were significantly higher prolactin and lower cortisol values during the first suckling as compared with the fourth suckling in primiparous but not in multiparous cows.

The goal of this study was to evaluate the dose dependent changes in common milk and blood parameters for udder health after an intramammary (IM) infusion of five different doses of lipopolysaccharide (LPS, 100, 50, 25, 12.5 and 6.25 μg, respectively). Ten Holstein Friesian cows randomly divided into five groups of 2 cows each were IM infused into one quarter with one LPS dose dissolved in 10 ml of saline. The contralateral quarter was infused with 10 ml saline (9 g/l). Milk samples were taken immediately before and 12, 24, 36, 48 and 60 hours after the treatment. All milk samples were analysed for somatic cell counts (SCC), lactose, sodium (Na), chloride (Cl) and electrical conductivity (EC). Two blood samples were taken immediately after milking for analysing leukocytes (WBC), polymorphonuclear neutrophils (PMN), Na and Cl. The SCC increased maximal at 12 hours after the LPS challenge and differed among LPS doses, as well as the area under curve from 0 to 36 hours (AUC 0-36 h). There were no significant differences among LPS doses in lactose levels for the regression at 12 hours and AUC 0-36 h. Lactose levels in milk from quarters receiving the lowest dose of LPS were lowest after 24 hours, whereas in all other groups lactose levels decreased maximal within the first 12 hours. The regression at 12 hours as well as the AUC 0-36 h showed significant changes for Cl levels but not for Na and EC, respectively. Amongst all groups EC increased maximal within 12 hours and peak EC showed dose dependent differences with highest values at the highest LPS dose. There were no dose differences in WBC. Blood electrolytes showed only tendentially dose dependent differences for blood Na in AUC 0-36 h. The results were possibly due to a great individual variance amongst all cows. In conclusion there are dose dependent differences in the response to LPS especially in milk parameters, which are likely caused by a greater tight junction damage by higher LPS doses. 100 μg LPS seems to be a threshold between low and high doses of LPS. All doses used in this study induced signs of mastitis but there might be a low dose of LPS with only an enhancing effect on mammary gland immune status without inducing mastitis symptoms. This needs to be investigated for developing new ways of mastitis prophylaxis.

The aim of this study was to test whether a more pronounced oxytocin release induced by naloxone during milking causes higher efficiency of milk removal. Eight pregnant multiparousHolsteincows from second to fifth lactation were used for this experiment. The experiment was carried out during three consecutive days, i.e. six milkings (three morning and three evening milkings). During first and third evening milking in cross over design (four and four animals) 250 mg of naloxone or 10 ml saline was injected 5 min before the start of udder preparation. During these milkings 2 IU of oxytocin was injected i.v. after stripping and the amount of milk obtained in response to oxytocin injection was measured. Pre-milking naloxone treatment increased the milking-related release of oxytocin, however, only in six of eight cows. The stimulatory effect of naloxone on oxytocin release in the mentioned six cows differed individually from 4 ng/l to 132 ng/l. Naloxone treatment did not influence milk yield before stripping and stripping milk yield. However, naloxone treatment significantly reduced the amount of milk obtained in response to oxytocin injection. Peak flow rate tended to be higher after naloxone treatment. In conclusion, oxytocin release seems to be very important for the evaluation of different milking routines and milk removal environment with respect to the welfare of dairy cows.

The objectives of our study were to describe the variation of quarter milk flow parameters and to determine the factors that affect these parameters the most. Additionally, repeatabilities (r2) of the quarter milk flow traits (duration of milk flow, time to reach peak flow, peak flow rate, and duration of milk flow in single phases - increase, plateau, decline and blind phase) were calculated. Repeatability of total milk yield and milk yield in single phases was calculated, too. The data from 39 Holstein cows, in their first to third lactation and free of clinical mastitis, were used for statistical analysis. A total of 1 656 curves of quarter milk flows were recorded during six consecutive days. At the last evening and morning milking samples of milk from each quarter were collected for determination of somatic cell count (SCC). Peak flow rate, quarter position, time of milking (morning and evening) and SCC significantly affected most of the measured traits. The highest r2 were for total milk yield and yield of plateau phase 0.53 and 0.50, resp. The lowest r2 were calculated for the duration of increase phase, and milk yield of the increase and blind phase 0.26, 0.12 and 0.21, resp. Peak flow rate, SCC, time of milking and front-rear position influenced the values of r2 of traits to various extent.

The study aimed to determine the content of 17 elements (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Li, Mn, Mo, Ni, Pb, Sb, Se, Sr, and Zn) in samples of sheep milk, cheese, and whey (36 samples in total) collected from a farm in an environmentally burdened area due to the long-term mining and industrial activity in Slovakia as well as to determine the possible risk of consumption via health risk assessment calculations. Consumption of 120 g of milk, 500 g of milk, 20 g of cheese, and 100 g of cheese were used in calculations for children and adults, respectively. According to the results, concentrations of four elements are controversial. Lead concentrations in all types of samples exceeded the maximum permissible lead limit in milk set by European Union legislation. The content of Se and As is problematic for children's consumption, and the target hazard quotient for As and Al is higher than one (considered potentially not safe) in all scenarios. According to the target system approach, lead concentrations in milk and cheese could adversely influence the nervous system and kidneys of adults' and children's developmental and reproductive systems. Considering the worst-case scenario, consuming sheep milk and cheese from the monitored areas could represent a risk and be potentially harmful to human health, mainly for children. However, further monitoring of the levels of elements and concentrations in environmentally burdened areas and more robust data on consumption are needed.

This study determined effects of milk production, milk components, or fatty acids (FA) profile on live weight of suckling lambs till their weaning. Live weight (LW, kg) of 42 purebred Wallachian lambs (from 33 ewes) was recorded during four control days with approximately 30-day intervals during rearing. At the same time, their mothers were examined for milk production (kg), milk fat (g), proteins (g), lactose (g), and fatty acids (%) contents. Results investigated using linear regression analysis showed 5.93 kg ( p < 0.05) increase of lambs LW corresponded with 1 kg of ewe's daily milk production increase during the observed period. Similarly, significant 0.13 kg or 0.11 kg increases of lambs live weight corresponded with 1 g increase of milk protein or milk lactose at this time. Milk with higher prevalence of trans-palmitoleic acid, trans-vaccenic acid, cis-vaccenic acid, linolelaidic acid, linoleic acid, or conjugated linolenic acid (CLA) significantly improved lambs LW. Moreover, significantly positive Pearson partial correlation between LW and trans-vaccenic acid (r = 0.305) or CLA (r = 0.347) indicated on genetic correlation between these traits. Therefore, milk (natural or artificially supplied) with higher distribution of these specified FAs could improve lambs' LW.