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Despite many genetic and environmental factors, the level of physical activity may be a very good indicator of the physiological (e.g. estrus, approaching parturition) or health status of cows. The aim of this study was to analyse the 24-hour walking activity of lactating cows as related to the milk yielded in particular milkings over two stages of lactation. Used were 41 cows in early lactation (group G1) and 54 cows in late lactation undergoing a gradual decline in milk production (group G2). Activity of animals was measured with activity meters and expressed in Alpro units (AU), version 6.5 by DeLaval. The cows were kept in a loose system in one common building and milked three times a day in a milking parlour. Two hours before morning and evening milking the G2 cows occurred more active than cows G1 (43 and 45 vs. 26 and 31 AU, respectively). From morning to noon milking the G1 cows showed significantly lower activity (33 AU) than G2 cows (40 AU). The highest positive significant correlation coefficients (r) were estimated for G1 cows between milk yield at noon and mean 24-hour activity, mean activity between morning and noon milking, and mean activity associated with partial mixed rations (PMR) intake between evening milking and first (morning) PMR feeding (r = 0.47-0.48). The r coefficients between investigated indicators were generally lower in G2 than in G1 cows.
The material of the study consisted of 140 cows of PHF breed, reared in the farm equipped with the automatic milking system (AMS). Cows in different lactations (from 1 to 5) were reared in the period from May 2011 to April 2013. The daily distribution of milkings (12, two-hours periods) was analyzed according to: cows’ age (primiparous and multiparous), the average milk production per milking during the whole lactation (<12.5 kg, ≥12.5 kg) and season (spring, summer, autumn, winter). The statistical analysis was conducted with the use of the χ2 independence test. It was noted that the daily distribution of milkings was statistically conditioned by all analyzed factors. The first peak of the increased milking frequency was obtained during midday hours and the next one during late night hours, i.e. during hours that are generally different from the typical milking hours in farms that do not use AMS. The lowest milking frequency was recorded during milking hours typical for farms that do not use the AMS.
Automated control systems for technical processes in dairy farming. Monitored parameters, evaluated data and formed control and operating commands for technical processes of individual animal service are presented. Perspective directions for the development of automated control systems for technical processes of machinery milking, feeding, livestock and maintenance in dairy farming based on precision (highly accurate) technologies and technical means are substantiated.
The investigation was conducted during 2005-2006 on 4010 dairy cows. Having performed statistical data analysis, we determined that the lowest somatic cell count (SCC) in Red and Red-White cow population was obtained when the milking time was 5-6 min., milking speed was higher than 1.5 kg/min., high milk flow was from 2.51 to 4 kg/min., and in Black-White cow population having a milking time was higher than 7 min., milking speed was from 1.01 to 2 kg/min., a high milk flow – from 2.01 to 4 kg/min. (p<0.001). In Red and Red-White cow population with subclinical mastitis, milking time was longer and milking speed was slower than in healthy cows. High milk flow values were least in healthy Black-White cow population. This determines a more equal milk flow which is desired in milking cows mechanically. Most sensitive to udder infection are 1st lactation cows which have a higher milk flow. A larger phenotype correlation coefficient in Red and Red-White cow population was between the SCC and milking time (-0.089, p<0.01) and between high milk flow (0.086, p<0.01) and milk yield (-0.071, p<0.05). However in Black-White cow population, correlation was found between SCC and milk yield (-0.117, p<0.01) and milking speed (-0.110, p<0.01). Contagious mastitis pathogens were identified in Red and Red-White cow milk samples primarily from productive cows having a milking speed of 1.01-1.5 kg/min., and in Black-White cow population having a milking speed of 1.51-2.0 kg/min.
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