Parity affects calving interval in dual-purpose cattle in the Mexican tropics

Total merit indices in dual purpose cattle

The economic efficiency of dual purpose cattle is influenced by a large number of traits which may be classified in groups of dairy, beef and functional traits. The combination of estimated breeding values for single traits in a total merit index, as long practised in some Scandinavian countries, is currently being implemented in a number of Central European states. Economic values for populati...

G enetic relationships between calving date, calving interval, age at first calving and type traits in beef cattle

In this paper the genetic relationships between major reproductive traits in beef cattle (Calving Date, Calving Interval and Age at First Calving) and type traits have been estimated to evaluate the usefulness of type classification in predicting reproductive performance in beef cattle. We estimated favourable genetic correlations between Calving Interval and type traits ranging from 2 0.027 to...

Calving Difficulty in Beef Cattle

Low Cost Feeding Strategies for Dual Purpose Cattle in Venezuela

This simulation study was to evaluate low cost feeding strategies in response to higher cost of commercial concentrates to maintain current milk sales from dual purpose cattle herds in the humid lowlands of western Venezuela. Data were from farm surveys in 1987 and 1988. Baseline net margins from milk and beef per cow per year were $132 and $99 for two farm cases with average dally milk of 10 a...

the effect of oxytetracycline on serum calcium, phosphorus and magnesium in cattle

نتایج این مطالعه نشان می دهد که مقدار کلسیم (یونیزه و تام)، منیزیم و فسفر به طور معنی داری تغییر پیدا کرد به جزء مقدار کلسیم تام و منیزیم در روش داخل عضلانی که تغییر معنی داری نداشته است. بر اساس نتایج این مطالعه می توان نتیجه گیری کرد که اکسی تتراساکلین بر روی مقادیر سرمی کلسیم و منیزیم تأثیر می گذارد باید مقدار این کاتیون ها در بیماران، در هنگامی که اکسی تتراسایکلین استفاده می شود مورد توجه ق...