Author/Editor		Pestevšek, U; Žust, J; Vengušt, A
Title		Vpliv obroka z velikim deležem voluminozne krme na potek vampove fermentacije ter količino in kakovost mleka pri kravah
Translated title		Influence of a high roughage diet for dairy cows on rumen fermentation, milk production and quality of milk
Type		članek
Source		Slov Vet Res
Vol. and No.		Letnik 38, št. 4
Publication year		2001
Volume		str. 327-34
Language		slo, eng
Abstract		The rumen fermentation in dairy cows fed mainly on a high roughage diet and its influence on their milk yield and milk quality was investigated. Rumen fluid examinations showed characteristically high pH values of between 6.4 +- 0.2 and 6.8 +- 0.2, low concentrations of total volatile fatty acids (from 89.3 +- 15.7 mmol/1 to 103.4 +- 17.4 mmol/1) and a wide lipogenic - glucogenic ratio between (acetic + butyric)/ propionic acid (4.3 +- 0.6 to 5.0 +- 0.8). A statistically significant positive correlation (r = 0.755 and r = 0.8377, P< 0.001) was found between the milk yield, dry matter intake and available net energy for lactation, however, the correlation between dietary crude protein content and milk production was not significant. Greater dry matter intake was positively correlated (P < 0.05) with the concentration of propionic acid and negatively with the concentration of acetic acid and the lipogenic - glucogenic ratio of rumen fluid. The relationship between rumen fermentation and milk composition in the postpartum period showed a greater influence of rumen fermentation on the milk yield than on its composition. Simple indigestion occurred in 6.8% of experimental cows.
Summary		Avtorji so proučevali potek vampove fermentacije in njen vpliv na količino in kakovost mleka ter na zdravstveno stanje pri kravah, ki so bile krmljene pretežno z voluminozno krmo. S preiskavami vampovega soka so odkrili na vseh gospodarstvih značilno povišane pH vrednosti, ki so se gibale med 6,4 +- 0,2 in 6,8 +- 0,2, majhno količino skupnih hlapnih maščobnih kislin (89,3 +- 15,7 mmol/1 do 103,4 +- 17,4 mmol/1) in široko lipogeno-glukogeno razmerje med (ocetno + masleno)/ propionsko kislino (4,3 +- 0,6 do 5,0 +- 0,8). Med količino zaužite suhe snovi in neto energije za laktacijo v primerjavi s količino proizvedenega mleka je bila ugotovljena zelo ozka statistično značilna pozitivna povezava (r = 0,755 in 0,8377, P < 0,001), povezava med količino surovih beljakovin v obroku in mlečnostjo pa ni bila značilna. Več zaužite suhe snovi je bilo na stopnji P < 0,05 pozitivno povezano z deležem propionske kisline in negativno z deležem ocetne kisline in lipogenim glukogenim razmerjem v vampovem soku. Odnosi med fermentacijo v vampu ter količino in sestavo mleka v poporodnem obdobju in v sredini laktacije kažejo na večji vpliv vampove fermentacije na količino kot na sestavo mleka. Za neaktivnostjo vampove vsebine je v poskusnem obdobju zbolelo 6,8% krav.
Descriptors		ANIMAL FEED RUMEN FERMENTATION GASTRIC JUICE MILK CATTLE ENERGY METABOLISM LACTATION HYDROGEN-ION CONCENTRATION ACETIC ACID AMMONIA BUTYRIC ACIDS PROPIONIC ACIDS FATTY ACIDS, VOLATILE CHROMATOGRAPHY, GAS MILK PROTEINS FATS LACTOSE UREA