To identify strains of Mycobacterium bovis circulating in Iran, we used region of difference, spoligotypes, and variable number tandem repeats to genotype 132 M. bovis isolates from Holstein Friesian cattle. Despite wide geographic origins, the strains were genetically homogeneous. Increased distribution of cattle herds and inadequate control measures may have contributed to strain dispersion.

Introducción. En el ciclo de producción los bovinos leche, tiempo crecimiento las terneras representan un período gastos y poco retorno para productor, sin embargo, la preparación hembras saludables durante este es fundamental incorporar al hato productivas que garanticen financiero. Objetivo. Determinar parámetros productivos bovinométricos filiales uno (F1) dos (F2) producto del cruce entre r...

The development of effective genetic evaluations and selection of sires requires accurate estimates of genetic parameters for all economically important traits in the breeding goal. The main objective of this study was to assess the relative performance of the traditional lactation average model (LAM) against the random regression test-day model (RRM) in the estimation of genetic parameters and...

Whole-crop wheat treated with 40 kg urea/t/DM was examined in two experiments as the sole forage offered ad libitum. The objective was to evaluate the nutritive value of the forage, and the response in milk production to energy and protein supplements. In Experiment 1, 12 Holstein Friesian lactating cows in three 4 4 Latin squares were offered four concentrates, AÐ6 kg/day of 208 g CP kg/DM, BÐ...

Selection pressure for greater milk solid production, calving ease and early puberty attainment has resulted in the alteration of growth trajectory New Zealand dairy heifers. Although previous data have looked at stature terms height girth, changes as a result seasonal not been examined. In addition, relative contributions appendicular skeleton thorax relation to considered studies. Therefore, ...

Data from 113 Dutch organic farms were analysed to determine the effect of cross-breeding on production and functional traits. In total, data on 33 788 lactations between January 2003 and February 2009 from 15 015 cows were available. Holstein-Friesian pure-bred cows produced most kg of milk in 305 days, but with the lowest percentages of fat and protein of all pure-bred cows in the data set. C...

This study was conducted at Sarsha Upazila in Jessore district of Bangladesh to capture a scenario of productive and reproductive performances of different genotypes such as Holstein-Friesian cross, Sahiwal cross, Sindhi cross with local, and indigenous dairy cows. Data were collected by live survey on 100 cows, divided into 4 groups each consists of 25 animals. Results shows that age at first ...