Reticulo-ruminal pH and temperature relationship between dairy cow productivity and milk composition
¹ Latvia University of Agriculture, Faculty of Veterinary Medicine, Clinical Institute, Kr. Helmana street 8, LV-3004 Jelgava, Latvia
² Latvia University of Agriculture, Faculty of Agriculture, Institute of Agrobiotechnology, Liela street 2, LV-3001 Jelgava, Latvia
The aim of the research was to establish interrelations between reticulo-ruminal pH and temperature, cows’ productivity and milk composition (milk fat, protein, lactose, somatic cell count and electrical conductivity of milk) by using specific SmaXtec reticulo-ruminal boluses. In the research were included four different age dairy cows in early lactation period. The reticuloruminal pH and temperature was measured every 600 sec. over a 79 day period. The milk yield and quality was registered three times per day with automated data recording and management system Afmilk. Results showed that reticulo-ruminal temperature brightly demonstrates cow drinking behaviour and did not influence any of the investigated milk parameters. There was established a weak, statistically significant correlation between reticulo-ruminal pH and energetically corrected milk (r = 0.19; P < 0.01), milk protein level (r = 0.35) and a weak negative correlation between milk fat/protein ratio (r = − 0.22; P < 0.01). No relation between reticuloruminal pH, milk somatic cell count and milk electroconductivity was observed. Reticulo-ruminal pH fluctuations were at individual ranges for each cow without affecting an individual milk fat/protein ratio despite all of them received the same ration. It seems that milk fat/protein ratio is primarily dependent on the feed composition and properties. In the study was included one cow whose reticulo-ruminal pH was decreased below 5.7 for 400 min. in a day, and it had not had any individual effect on milk fat/protein ratio. That fact indicates to an individual cow tolerance to subacute rumen acidosis.