Blood sampling to record energy balance in lactating Norwegian Red cows
1 Formål
Recently, there has been a special focus on improved breeding strategies to increase the feed efficiency and robustness of fish and farm animals. The overall aim of this experiment is, therefore, to investigate if there is a relationship between stable isotope profiling in milk and feed efficiency in lactating Norwegian Red cows (NR). During this trial, the cows will be fed a total mixed ration based on roughage and concentrate to assess individual feed efficiency in NR, by using the natural abundance of the stable isotopes 15N and 13C. However, the natural abundance of stable isotopes in milk is dependent on the abundance in feed and animal tissues. As we are not able to establish the natural abundance of isotopes in animal tissues it is necessary to take a blood sample to record the change in energy balance. The state of energy balance would give an indication to what degree the isotope profile is affected by the degradation of animal tissue during the 60-day experiment.
2 Skadevirkninger
The animals to be used in the present experiment are already kept at the Center for livestock production (SHF) at Ås and are therefore used to the facilities and the environment. The cows are therefore expected to adapt readily to the experimental situation.
3 Forventet nytteverdi
The experiment is part of an IPN-project which focuses on genetic improvement of feed efficiency of Norwegian Red cows (NR). The aim is to support genetic adaptation and identify new selection criteria for NR, with the major goal to develop a method for large-scale evaluation of feed efficiency in livestock production. The results from this experiment will be used to develop a method for large-scale phenotyping of feed efficiency in NR. As the feed amount to ~70% of the variable costs in agriculture, an improvement in feed efficiency by 1% will lead to a value creation for terrestrial animals of 81 million NOK and reduce the environmental footprint per unit produced.
4 Antall dyr og art
A total of eight Norwegian Red cows will be individually fed a total mixed ration and daily individual milk samples per cow will be collected for 60-days. During the 60-days, blood samples will be collected at days 0, 5, 15, 25, 35, 45, and 55 days after calving to register the change in energy balance. In addition, the live weight will be registered at days 2, 3, 29, 30, 59, and 60 to register the change in live weight.
5 Hvordan etterleve 3R
This study follows the milk production of individual cows, thus blood sampling and handling of the cows will involve some level of stress, but we aim to minimize the stress by using standard procedures and trained personnel. The results will provide vital knowledge that can be used to select more efficiently for feed efficiency in livestock breeding programs. Furthermore, there are no available in vitro models that can mimic entire body systems, thus it is not possible to use in vitro methods.
Recently, there has been a special focus on improved breeding strategies to increase the feed efficiency and robustness of fish and farm animals. The overall aim of this experiment is, therefore, to investigate if there is a relationship between stable isotope profiling in milk and feed efficiency in lactating Norwegian Red cows (NR). During this trial, the cows will be fed a total mixed ration based on roughage and concentrate to assess individual feed efficiency in NR, by using the natural abundance of the stable isotopes 15N and 13C. However, the natural abundance of stable isotopes in milk is dependent on the abundance in feed and animal tissues. As we are not able to establish the natural abundance of isotopes in animal tissues it is necessary to take a blood sample to record the change in energy balance. The state of energy balance would give an indication to what degree the isotope profile is affected by the degradation of animal tissue during the 60-day experiment.
2 Skadevirkninger
The animals to be used in the present experiment are already kept at the Center for livestock production (SHF) at Ås and are therefore used to the facilities and the environment. The cows are therefore expected to adapt readily to the experimental situation.
3 Forventet nytteverdi
The experiment is part of an IPN-project which focuses on genetic improvement of feed efficiency of Norwegian Red cows (NR). The aim is to support genetic adaptation and identify new selection criteria for NR, with the major goal to develop a method for large-scale evaluation of feed efficiency in livestock production. The results from this experiment will be used to develop a method for large-scale phenotyping of feed efficiency in NR. As the feed amount to ~70% of the variable costs in agriculture, an improvement in feed efficiency by 1% will lead to a value creation for terrestrial animals of 81 million NOK and reduce the environmental footprint per unit produced.
4 Antall dyr og art
A total of eight Norwegian Red cows will be individually fed a total mixed ration and daily individual milk samples per cow will be collected for 60-days. During the 60-days, blood samples will be collected at days 0, 5, 15, 25, 35, 45, and 55 days after calving to register the change in energy balance. In addition, the live weight will be registered at days 2, 3, 29, 30, 59, and 60 to register the change in live weight.
5 Hvordan etterleve 3R
This study follows the milk production of individual cows, thus blood sampling and handling of the cows will involve some level of stress, but we aim to minimize the stress by using standard procedures and trained personnel. The results will provide vital knowledge that can be used to select more efficiently for feed efficiency in livestock breeding programs. Furthermore, there are no available in vitro models that can mimic entire body systems, thus it is not possible to use in vitro methods.