objective: this study carried out to monitor the status of nutritional management and measuring difference between present and desired feeding system in dairy cattle of rural conditions of chaharmahal and bakhtiari. methods: 334 rural flocks consisting of 1442 dairy cows were selected from seven towns of this province. the experiment was lasted for in a year and using completely randomized desi...

the present study was conducted on efficiency of utilization of dietary energy for milk production in lactating crossbred cattle. 18 lactating crossbred cattle of early to mid-lactation, approximate body weight (375.39±23.43 kg), milk yield, parity and stage of lactation were divided into three groups of six animals each and were fed 0, 50 and 100% diammonium phosphate (dap) in the mineral mixt...

The present study was conducted on efficiency of utilization of dietary energy for milk production in lactating crossbred cattle. 18 lactating crossbred cattle of early to mid-lactation, approximate body weight (375.39±23.43 kg), milk yield, parity and stage of lactation were divided into three groups of six animals each and were fed 0, 50 and 100% diammonium phosphate (DAP) in the mineral mixt...

In the dynamic modeling of dairy cow performance over a full lactation, the difference between net energy intake and net energy used for maintenance, growth, and output in milk accumulates in body reserves. A simple dynamic model of net energy balance was constructed to select, out of some common dry matter intake (DMI) prediction equations, the one that resulted in a minimum cumulative bias in...

Lactation has long been recognized as a major determinant of interbirth intervals. The temporal pattern of nursing has been proposed as the mechanism behind lactational amenorrhea. We present a new model of the dynamic regulation of lactational amenorrhea that identifies maternal energy availability as the main determinant of ovarian resumption. Variation in the intensity of lactation remains a...

Three ethanol extracts, chamomile (CHA), clove (CLO) and tarragon (TAR), were tested at five doses (0, 250, 500, 750 and 1000 µL/L) to determine their effects on in vitro organic matter digestibility (IVOMD), metabolizable energy (ME), net energy of lactation (NEL), short-chain fatty acids (SCFA), microbial mass (MM) and rumen fermentation kinetics of a 40:60 forage: concentrate diet using in v...

At the dairy research farm Karkendamm, the individual roughage intake was measured since 1 September 2005 using a computerised scale system to estimate daily energy balances as the difference between energy intake and calculated energy requirements for lactation and maintenance. Data of 289 heifers with observations between the 11th and 180th day of lactation over a period of 487 days were anal...