In light of the global challenges concerning food security, the Norwegian Parliament states that national self-sufficiency of food production is a political goal. Ruminants are able to utilize rangeland pasture and grass produced on farmland where the climate is too rough to grow food for human consumption. Enhanced nutrition and better management of dairy calves, in order to decrease calf mortality and increase the number of quality calves that reaches slaughter weight, has been emphasised as a strategy to increase the domestic beef volume. The QualityCalf project investigated the relationship between feeding, management and the effects on calf health, welfare and production, with the aim of providing science-based recommendations for a sustainable calf production.
Timely delivery of high quality colostrum is essential to protect calves from infections during their first weeks of life. We found that the content of immunoglobulin G (IgG) in colostrum varied substantially among cows as well as among farms. More than 70% of the samples were of poor quality according to the international limit drawn at 50 g IgG/L colostrum. Quality was lower in winter and for 2nd lactation cows. We found good correlation between the gold standard laboratory method (RID) and an indirect method (Brix refractometer) which can be used on-farm. A cut-off Brix value of 22 seems appropriate. Data combining cow colostrum quality and individual registration on several factors including dry period length, udder health, feeding and metabolic state, remains to be published. As many of 1/3 of the calves tested 24-48 h after birth had lower serum IgG levels than the internationally set recommendation of minimum 10 g/L, thus being at higher risk for infections. Such calves may benefit from special care and therefore the farmer should be able to identify them. In Norway, only veterinarians are allowed to take blood samples. Thus, we explored whether IgG can be detected using a non-invasive method; calf saliva and a Brix refractometer. We found a strong correlation between serum IgG and saliva Brix values at the higher levels, which was promising. However, we were unable to detect the calves at risk, so more work is needed.
Calf management was investigated at 508 randomly selected Norwegian dairy farms using a questionnaire. We found that 60% of the farmers fed their 3 w old calves less milk than the current industry recommendation of 8 L/d. The most common milk allowance was 7 L/d. Milk replacer was used by 45% of the farmers, usually from when the calves were 2 w old. Most calves were moved to a group pen at the age of 2-3 w, which is positive for their physical and mental development. All farms were visited by the Competent Authority, controlling compliance with the national calf welfare legislation. The farmers allowed us access to the national herd database on calf diseases and mortality. Data from these sources were analysed together. Only two risk factors for increased calf mortality were found; lack of free access to drinking water (found on 16% of the farms) and recorded calf diseases.
Many farmers are reluctant to feed calves more than 2-3 L milk per meal because they fear that larger portions will cause milk to enter the rumen, resulting in indigestions. In a former experiment, we had studied digestive physiology of dairy calves fed milk until satiety, up to 7 L/meal. Here, we investigated the effects of drinking speed and milk temperature, using the same method: radiography after calves had consumed 4 L milk with a contrast agent added to it. Just like in the first experiment, all milk ended up in the abomasum with no traces found in the fore-stomachs. However, cold milk could reduce the milk intake and made some calves shiver. Further, a large aperture teat will not satisfy the behavioural need of calves for sucking.
We aimed to evaluate a weaning method tailoring the weaning process to each individual calf (concentrate dependent weaning). Unfortunately, this experiment met many and severe challenges and was not successful.
In conclusion, QualityCalf has provided sound science that also is practically applicable for farmers. The projects has resulted in six scientific papers published in peer reviewed journals and more are in progress. Results have been disseminated at many user meetings and in magazines for farmers, advisors and veterinarians. Due to the close collaboration with the industry, results have already been implemented in recommendations and advisory work.
The project was a research collaboration between the Norwegian Veterinary Institute and the University of Life Sciences and the University of British Colombia. It was funded by the Foundation for Research Levy on Agricultural Products (FFL) and the Agricultural Agreement Research Fund (JA). The project also received financial support from Fjellandbruksatsningen, Tine SA and Norgesfôr. Further, Mattilsynet, DeLaval and Nortura have contributed.
Prosjektet har ført til økt oppmerksomhet om viktigheten av godt kalvestell generelt og råmelkskvalitet og økt melkemengde spesielt. Vi har påvist en meget stor variasjon i innholdet av immunglobulin G i råmelk, og har avdekket noen årsaksfaktorer. Variasjonen i kvalitet bør hensynstas på den enkelte gård. Vi har tilbakevist myten om at kalver bare kan gis små porsjoner melk, noe som gjør det enklere å øke melkemengden. Fri tilgang til drikkevann er viktig også for spedkalver, og mangel på dette økte risikoen for kalvedød. Gjennom hyppig formidling til brukere (bønder og veterinærer) og tett samarbeid med næringsaktører og deres veiledningstjenester håper vi at prosjektet vil føre til mer robuste kalver, som holder seg friske og har god velferd, noe som også bidrar til en bedre ressursutnyttelse og økt selvforsyningsgrad av storfekjøtt. Postdoc-opplæringen i prosjektet har vært meget vellykket og vil være av stor nytte for Veterinærinstituttet og kommende forskning innen dyrevelferd.
The QualityCalf project will investigate the relationship between feeding management strategies and their effects on calf health, welfare and production, with the aim of providing science-based recommendations for a sustainable calf production. The project will provide new knowledge on how to improve colostrum quality, milk feeding management and weaning of calves, building on two recent PhD theses on calf welfare from our research group. The Norwegian Parliament states that national self-sufficiency of food production is a political goal. There is a significant market undersupply of domestic beef, covered by import. Enhanced nutrition and management in order to decrease calf mortality and increase the number of quality calves that reaches slaughter weight, has been emphasized in order to increase the domestic beef volume. However, more knowledge about colostrum quality and calf feeding strategies is needed before this potential can be harvested. Thus, the QualityCalf project will evaluate the importance of different on-farm factors on colostrum quality in Norwegian dairy herds (WP1); and investigate management routines in 500 Norwegian dairy herds to evaluate the association between milk feeding routines and herd level indicators of calf health and welfare (WP2a). Risk factors associated with feeding dairy calves high milk allowances will also be investigated (WP2b). Finally, the project will evaluate if individualized concentrate-dependent weaning makes the transition from milk to solid feed smoother compared to traditional weaning in NRF calves (WP3). The project will produce results that are practically applicable for farmers and advisory services, and communication of the results to end-users is highly prioritized. The project will provide an important basis for recommendations for the industry, ensuring high standards of animal health and welfare, better economic output and the development of a sustainable and increased production of beef as well as milk.