The slaughter age of cattle can be reduced on most farms “without necessarily increasing production costs or lowering carcass weights”, according to Teagasc’s Dr. Peter Lawrence.
In a recent post on the Teagasc website, he explained that the slaughter age of cattle can be reduced through improvements in genetics, nutrition, and health.
He said: “Many farmers are aware of the Irish Governments Climate Action Plan and its strategies to reduce greenhouse gas (GHG) emissions in agriculture by 25% from the reference year of 2018 to 2030.
“One of the main contributors to GHG emissions in agriculture is enteric fermentation from the digestive process in our ruminant animals where methane gas is released.
“Consequently, one of many measures to reducing methane is to reduce the average age of slaughter in our national cattle herd.
“Currently, the average age-of-slaughter in Irish steers is 26-months-of-age. The target is to reduce this down to 22-23 months by 2030.
“It is estimated that for every one-month reduction in the national average age of slaughter, the reduction is equivalent to the emissions from approximately 100,000 cows.”
He said that there are “three main areas where farmers should focus on to improve the animal performance of their beef system and help achieve a reduction in cattle slaughter age, without necessarily increasing production costs or lowering carcass weights”.
These three main areas are:
- Genetics;
- Nutrition;
- Health.
Commenting on the role of genetics, the Teagasc advisor said: “Traditionally, breeders were selecting to breed animals destined for slaughter with high growth rates, high carcass weights and carcass conformation.
“The recent revision of the beef-breeding indexes now include ‘Age to Finish’ as a new trait.
“This will help suckler farmers and dairy farmers breed beef animals that will be slaughtered at a younger age that are more efficient and less costly whilst not comprising carcass traits.”
He added that: “Research in Teagasc Grange has consistently shown that cow milk yield is the driver of calf weaning weight and this weight advantage remains with the calf right up to slaughter.
“Therefore, suckler farmers should aim to breed from cows with good milk yield, or from bulls with good milk traits to maintain or improve the milk yield of their replacements”.
Nutrition
Dr. Peter Lawrence said: “Nutrition starts from the beginning of an animal’s life from its first feed of colostrum right the way through to their finishing diet for slaughter.
“During the grazing season, cattle grazing highly digestible young leafy grass with clover will grow better than animals offered stemmy grass which is high in fibre and low in digestibility.
“Similarly, during the winter housing period animals will grow and fatten better and faster when fed high DMD quality silage that is well preserved.”
“The finishing period of cattle is very important and diets must be balanced correctly for fibre, protein, minerals and vitamins and be high in energy content.”
Health
The Teagasc advisor said: “Health and performance of a beef enterprise is dependent on minimising an animal’s exposure to disease and maximising their defence against disease.
“Farmers should focus on prevention to limit the need for subsequent intervention. For the new-born calf, this starts with good hygiene, having well-bedded straw lying areas with fresh clean air and no draughts.”
The most common cause of severe scour in calves is associated with rotavirus infection.
Annual vaccination of the cow pre-calving with a combined rotavirus-coronavirus and E.coli (K99 and F41) vaccine is an effective way to help mitigate the risk of viral infection.
He outlined that the causes of pneumonia in cattle is multiple and complex. The main factors associated with susceptibility to pneumonia are:
- Stress (disbudding, weaning, mixing cattle);
- Overcrowding;
- Inadequate ventilation;
- Draughts;
- Fluctuating temperatures;
- Poor nutrition;
- Concurrent disease.
“Pneumonia can occur in young and older cattle and vaccination against IBR, RSV & PI-3 will give a broad protection against respiratory viruses. However, vaccination alone is not a replacement for good management, hygiene or bio-security.
“Internal parasites of cattle such as stomach worms, lung worms and liver fluke can really affect animal performance and thrive is not treated correctly.
“Therefore, it’s important to keep an eye for clinical signs, take feacal egg samples, get feedback from factories (e.g., liverfluke) and review the Beef HealthCheck data on ICBF.”
He reminded farmers that the farm vet should always be consulted with specific herd health problems, herd health planning and farm biosecurity.
Progress to date on lowering slaughter age
The Teagasc advisor noted that the age of both suckler and dairy bred cattle at slaughter “has been decreasing by one week/year in steers and by one day/year in heifers since 2011.”
He said that average carcass weights for steers is approximately 355kg and 315kg for heifers. This has decreased by 0.5kg/year for steers but increased by 1.2kg/year in heifers respectively.
“With great strides being made in improving animal genetics on farms, coupled with better management of grassland, nutrition and health, Irish farmers have the potential to reduce cattle age of slaughter and lower GHG’s,” he added.