What do you want to know about heat stress in dairy cows?
Fans and sprinklers cooling cows at 45degC in Pakistan. A Great Set-up!
It’s already May and the temperatures are rising in the Northern Hemisphere. In April, we have had 2 weeks over 28 degrees C and it’s guaranteed that hot weather is to come. Cows show heat stress from a Temperature Humidity Index of 65 (Bernabucci U.) and from there, milk volume, Dry Matter Intake and reproduction will ALL be affected. Do you know what priorities to apply on farms? When and where to place fans; what about sprinklers? What droplet size should you advise? What are the production and repro effects?
Inspire Cattle Solutions training 30 Young Vets in Belgium on Heat Stress for Elanco Animal Health
Bernabucci U., Biffani S., Buggiotti L.,
Vitali A., Lacetera N., Nardone A.,. 2014. “The effects of heat stress in
Italian Holstein dairy cattle”, .” Journal of Dairy Science
471-486.
Bernabucci U., Lacetera N., Baumgard L.H.,
Rhoads R.P., Ronchi B., Nardone A. 2010. “Metabolic and hormonal
acclimation to heat stress in domesticated ruminants.” Animal 4
(7): 1167-1183.
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The basics seem pretty simple: Income minus expenses = net profit. However, with milk prices varying all the time, sometimes by large amounts, it is hard to keep this equation in positive balance! Maximising the Net Profit is an advisor’s main goal!
Income is made from milk SOLD. This is not the same as milk obtained from the parlour: some may be used by the producer and friends/family. Some may be in withhold from drug use and colostrum; so it is good to know what volume of MILK SHIPPED FROM THE FARM is. Other income may be from calf sales, beef sales, surplus feed and bedding etc.
Costs can be many! Most costs on a dairy are in feed. See if you can work this out on a kg Dry Matter basis or ask your nutritionist. It is important to note here that GRASS IS NOT FREE! You still have to maintain it, cut it, store it etc. Other costs are in labour, rent, energy, water etc. Know all of these and you can work out your Net Profit.
Maximising this is THE goal
Profit can be maximised by 3 ways:
Increasing Herd Numbers can maximise cost of production
Milk price can be influenced by milk quality (fat%, protein%, SCC)
Cost of production can be influenced by reducing disease losses, increasing herd numbers and increasing labour efficiency
Volume of milk can be influenced by reducing disease, increasing feed intake, improving reproduction and 3 X daily milking
IOFC is a very popular way of working out how your feed costs work to produce one litre of milk. The principle of this lies in knowing the feed costs to maintain the cow (breathing, ruminating, movement, calf growth etc.). Every litre of milk produced on top of this requires a certain amount of kg of Dry Matter at your cost of feed for that time. Of course, the more litres of milk you get, the more “diluted” the maintenance cost becomes and the more efficient your IOFC is.
Summary
So IMPROVE YOUR PROFITS by choosing your advice wisely!
Managing People, Equipment, Procedures, Environment and Monitoring can all help to improve your Profits. Inspire Cattle Solutions are GREAT at this!
Bozic M., Newton
J., Thraen C.S., Gould B.W.,. 2012. “Mean-reversion in income over feed
cost margins: Evidence and implications for managing margin risk by US dairy
producers.” Journal of Dairy Science 95: 7417-7428.
doi:10.3168/jds.2012-5818.
The ultimate test of heifer management is to look at their average Age at First Calving (AFC). If this lies between 22-25 months there are some great benefits for your milking herd:
Increased Yield over whole lifetime
Better Udder Health in the First Lactation
Decreased culling risk in the first lactation
Increased likelihood to calve for a second time
Improved economics compared to AFC of <22 and >26 months
It has been published that the average AFC for the UK is 29 months (median 28 months), ranging up to 42 months! This is not a great statistic! Calving beyond 25 months of age is associated with lost future milk and greater risk of culling or not even reaching a second lactation. So many herds in the world are not achieving their potential by allowing heifers to grow more slowly.
How to achieve AFC targets
It’s all down to great management from the start!
It’s all in the raising! Good colostrum management, ad lib or >3 X daily feeding of milk to pre-wean calves, achieving 0.9kg/day pre-insemination growth and 0.5kg/day post-insemination growth are the keys to reaching first calving at 24 months. Any disease, parasites, insemination procedures, poor feed quality or poor feed access will affect this key performance indicator. It is up to us as advisors to work with farmers to minimise these risks and help them to reach their absolute potential! Together, we can do great things!
Eastham N.T., Coates A., Cripps P., Richardson H., Smith R., Oikonomou G.,. 2018. “Associations between age at first calving and subsequent lactation performance in UK Holstein and Holstein-Friesian dairy cows.” PlosOne 13 (6): e0197764 2.
Sherwin V.E., Hudson C.D., Henderson A., Green M.J.,. 2016. “The association between age at first calving and survival of first lactation heifers within dairy herds.” Animal 10 (11): 1877-1882 3.
Adamczyk K., Makulska J., Jagusiak W., Węglarz A.,. 2017. “Associations between strain, herd size, age at first calving, culling reason and lifetime performance characteristics in Holstein-Friesian cows.” Animal 11 (2): 327-334 4.
Hossein-Zadeh G. 2011. “Estimation of genetic and phenotypic relationships between age at first calving and productive performance in Iranian Holsteins.” Tropical Animal Health and Production 43 (5): 967-973 5.
Pirlo G., Miglior F., Speroni M.,. 2011. “Effect of age at first calving on production traits and on difference between milk yield returns and rearing costs in Italian Holsteins.” Journal of Dairy Science 83 (3): 603-608 6.
Elahi Torshizi M. 2016. “Effects of season and age at first calving on genetic and phenotypic characteristics of lactation curve parameters in Holstein cows.” Journal of Animal Science and Technology 58 (8): doi: 10.1186/s40781-016-0089-1 –
Heifers are the future of the herd: Their genetic potential and efficiency should be greater than the current cows so let’s raise them wisely! 20% of the costs on a dairy are from raising heifers and 50% of those costs are in feed: THIS IS NOT LOST MONEY: It’s your investment for the future! How can you make the most of growth rates?
They must EAT, EAT, EAT to reach 66% of adult weight at 13-15 months for insemination and 85% of adult weight at first calving. Working back, a 650kg Holstein cow needs to be around 550kg at calving (730 days old) and 410kg at insemination (445 days old). If they wean at 110kg at 100 days old, this means a target gain of (410-110)/345=0.87kg/day to insemination and (550-410)/(730-445)=0.5kg/day post-insemination to calving.
The VALUE of reaching these targets lies in improved YIELDS over a lifetime and decreased risk of culling in their fist lactation (Eastham, Sherwin, Adamczyk, Pirlo)
HOW do you achieve that?
Maximise intakes and keep them comfortable
Of course, FEED is important! Make sure they have enough ACCESS to feed together and make sure the feed is NOT SORTABLE: Fibre needs to be chopped short for heifers not to sort and leave it. Clean and accessible water is also important to maximise intakes. PROTEIN is very important and QUALITY counts, therefore choose a pellet mix aimed at 18% Crude Protein of good quality. 16% CP is acceptable but 18% have better growth rates (Broadwater). 2.4 to 2.6MCal/kg Metabolisable Energy (10.1 to 10.7MJ/kg) is also recommended. Comfortable, clean and spacious accommodation is also important for maximum rumination and lying times.
What you NEVER do is feed poor quality or even rotten silage to heifers because they are seen as an unnecessary cost. Look after them at this stage and they will reward you later!
Eastham N.T., Coates A., Cripps P., Richardson H., Smith R., Oikonomou G.,. 2018. “Associations between age at first calving and subsequent lactation performance in UK Holstein and Holstein-Friesian dairy cows.” PlosOne 13 (6): e0197764 2.
Sherwin V.E., Hudson C.D., Henderson A., Green M.J.,. 2016. “The association between age at first calving and survival of first lactation heifers within dairy herds.” Animal 10 (11): 1877-1882 3.
Adamczyk K., Makulska J., Jagusiak W., Węglarz A.,. 2017. “Associations between strain, herd size, age at first calving, culling reason and lifetime performance characteristics in Holstein-Friesian cows.” Animal 11 (2): 327-334 4.
Pirlo G., Miglior F., Speroni M.,. 2011. “Effect of age at first calving on production traits and on difference between milk yield returns and rearing costs in Italian Holsteins.” Journal of Dairy Science 83 (3): 603-608
Broadwater N., Chester-Jones H.,. 2011. eXtension: Feeding Strategies for Post-Weaned Dairy Heifers, 2 to 6 months of age. Accessed January 29, 2019
Increasing Pellet Intake from 0.1kg to 0.9kg/day can indicate when to wean
Most dairy farmers choose to wean their calves at a specific age, because they have always done this. IT DOESN’T HAVE TO BE LIKE THIS! When calves are weaned is determined by whether or not the rumen has developed enough to cope with solid food. So this is an economic decision based on price of milk replacer, milk and concentrate pellets, which all vary from month to month.
When calves are born, their guts act a bit like humans BUT after 3 weeks on 0.1-0.5kg/day calf pellets1, they are developing their ruminant-like, 4-stomached gut. It is the presence of solid feeds such as pellets, grasses and dry matter (straw) that influences this development
Rumen development from Dairy eXtension USDA
The calf will alter intake depending on when it is weaned: so work out the cost of this vs. the cost of milk you have available and alter accordingly1
From Dairy eXtension USDA
SUMMARY
As long as pellets and forage/fibre are given to a calf, its rumen will develop over the space of 3 weeks or so in order to cope with weaning to solid food. Management afterwards on starter intake amounts will allow calves to “catch up” depending on farm strategy. So weaning should really consider the costs of milk replacer, milk, pellets and forage from month to month.
Terre M., Pedrals E., Dalmau A., Bach A.,. 2013. “What do preweaned and weaned calves need in the diet: a high fibre or forage source?” Journal of Dairy Science 96: 5217-5225 2
Overvest M.A., Bergeron R., Haley D.B., DeVries T.J. 2016. “Effect of feed type and method of presentation on feeding behaviour, intake and growth of dairy calves fed a high level of milk.” Journal of Dairy Science 99: 317-327
