genetic and non-genetic correlations of the average somatic cell score (scs) at different stages oflactation (100, 150, 200, 305 and 365 days in milk) with lactation performance were estimated based on thefirst lactation records of iranian holstein calving during 2000 to 2009. (co) variance components wereestimated using derivative-free reml based on multiple traits animal models. the estimated...

The objective of this study was to estimates the genetic and environmental components for the lactation curve parameters, milk yield, age at first calving (AFC), calving interval (CI) and somatic cell count (SCC) in Iranian Holstein cows. The dataset consisted of 210625 test day records from 25883 cows with milk yield in the first parity recorded from July 2002 to September 2007 in a total of 9...

early weanling and rearing of lambs on milk replacer is an important act to increasing flock productivity. two experiments were carried out to compare the voluntary intake and nutrients digestibility ewe milk and commercial milk replacer and their feeding effects on the growth rate, feed intake and feed efficiency of suckling lambs. in experiment 1, eight lambs (two 4-lamb groups) at 31 to 34 d...

The aim of this study was to compare energy consumption in dairy farms with different sizes. Sources of energy include non renewable sources such as fossil fuel, and electricity and renewable sources such as forage, concentrate, machinery, labor, and water. The required data were collected from 42 dairy farms in Tehran province, Iran and were analyzed to assess energy consumption based on diffe...

The aim of this study was to use meta-analysis to identify the enteric methane (CH4) mitigation strategy that reduced CH4 emission without lowering production. To this end, a database initially developed was updated, compiling data from 61 publications (233 experiments) for various observations in dairy cattle on effects of hydrogen sink (H-sink), ionophore, lipid and conc...

For a beef cow to continue in an annual production cycle, she must rebreed within 3 mo after calving. Malnutrition during this period frequently results in failure of the cow to become pregnant. The energetic needs of the cow are increased by lactation, and additional energy is required for growth of the primiparous cow. Determining energy expenditures during the first 40 to 60 d postpartum is ...