The Value of Heterosis in Cow Herds: Lessons From the Past That Apply to Today

نویسنده

  • Matthew L. Spangler
چکیده

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Evaluation of Fertility and Calving Ease of Small Holder Indigenous Cattle Herds in Semi-Arid Zone of Nigeria

This study had the objective of determining the fertility and calving ease of small holder indigenous cattle herds inseminated with imported semen from proven sires. Sixty one indigenous cows of different breed origin (Bunaji, Sokoto Gudali and Rahaji) were selected from different herds across Jigawa state-Nigeria, and were used for this study. The selected dams were inseminated with semen from...

متن کامل

Characterisation and pattern of culling in Holstein-Friesian dairy herds in Khorasan Razavi Province, Northeast of Iran

To describe proportion and pattern of culling in commercial dairy herds of Khorasan Razavi Province, this survey was carried out from 21st March 2008 to 20th March 2009 in 15 industrialized dairy herds. For each culled cow data related to parity at culling, last calving to culling interval and primary reason for culling were recorded. Annual herd exit rate was 20.9%. Out of a total of 652 culle...

متن کامل

Accuracy of oestrus detection in cows and its economic impact on Shiraz dairy farms

No report has been published on the economical losses associated with errors in oestrus detection in cows under Iranian intensive dairy management. The following study was carried out to determine the accuracy of oestrus detection by farmers using artificial insemination in Shiraz dairy farms. Milk samples were collected from 179 Holstein milking cows at the time of artificial insemination. Mil...

متن کامل

COVID-19 Outbreak in Africa: Lessons and Insights from the West African Ebola Virus Disease Epidemics

Over the years, the African continent has had to battle several outbreaks of infectious diseases in different countries. Some of the most deadly were the Ebola virus disease (EVD) outbreaks that occurred in West Africa between 2014 and 2016 affecting Guinea, Liberia, and Sierra Leone and, more recently, from 2018 to 2020 in the Democratic Republic of Congo (DRC). In the era of the COVID-19 pand...

متن کامل

Estimation of Economic Value for Production, Reproductive and Survival Traits of Buffaloes of Khuzestan Province in Two Milk Sale Conditions

In this study, production, population and economic parameters of 30 buffalo herds of Khuzestan province in two sale conditions during 2016-2017 were used to estimate the economic value for production, reproductive and survival traits. Economic value of the traits were estimated by one unit increase for each trait using the maximum profit trend. The average annual revenue, cost and profit per he...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2017