Summer sun is not so great for everyone!

Educational
Written By The Dairy Vet Team

Whilst some people revel in lying on the beach or by the pool, swimming the days away and soaking up the warmth of the summer sun, there are some that are faced with many challenges caused by drought conditions.  Most New Zealand Farmers utilise a primarily pasture based system and so, in the absence of having a large stock of conserved feed, having planted summer crops and/or drought tolerant pasture, may be struggling to provide adequate feed to their cows.  So, here’s a quick word on animal health and welfare during a drought.

Remember the FIVE FREEDOMS – the core of good animal welfare  

With the risk of sounding heavy handed… these apply rain, hail or shine and are non-negotiable and enforceable by law under the Animal Welfare Act 1999.  They apply to ALL animals, from domestic pets to production animals alike: 

  1. Freedom from hunger and thirst – all animals need clean water and adequate nutritionally appropriate food 

  2. Freedom from discomfort – all animals need a suitable place to live – this includes shelter and an area where they can rest 

  3. Freedom from pain, injury and disease – all animals must be regularly checked upon and given care and veterinary attention if required 

  4. Freedom to behave naturally – all animals must have enough space to move around 

  5. Freedom from fear and distress – all animals must have a quality of life 

In drought conditions all of the above obviously still apply but the three key ones are the absolute need for unlimited access to clean water (a lactating cow typically needs upwards of 100 litres per day!), provision of adequate suitable feed (remember if introducing a novel feed then do so slowly over 10-14 days to avoid rumen upset) and provision of some form of shelter/shade (ideally 5m2 per cow). 

Heat stress is real 

A cows’ “comfort zone” is said to be within the temperature of 4-20ºC (Dairy NZ) but humidity and air movement (one time that Manawatu wind is good!) are also important.  Outwardly visible signs of over-heating include: 

  • Agitation and restlessness 

  • Increased respiration rate – open mouth and laboured breathing 

  • Increased sweating and salivation 

  • Increased water intake 

  • Altered behaviour – decreased feeding, seek out shade, stand in or right by trough, reluctance to lye down etc  

  • Decreased milk production and change in milk composition - decrease in fat and protein percentages 

  • Increase in some health issues – weight loss, metritis, laminitis, acidosis, milk fever, fertility problems etc 

You can’t change the weather but you can do small things to help such as trying to reducing walking distance and speed to the shed, minimise any handling stress, milk earlier in the morning and later in the evening, use sprinklers while cows are in the yard etc. 

Remember young stock 

Young stock can be really sensitive to the stress of dry weather and they must be monitored regularly, especially if grazed off farm, for signs of ill health or stress.  Depending on their condition prior to a drought, their resilience is generally less than that of adults and, as such, special attention is required to keep them healthy and growing.   

Remember rain is not an instant fix AND may bring risks 

Depending on the degree of pasture damage it will take a number of weeks for grass to bounce back after a drought, so supplemental feeding of stock to provide adequate nutrition will likely be needed for at least a month or more longer.   In addition, once the rain returns, it may bring with it a number of heightened potential animal health risks, particularly: 

  • Facial eczema 

  • Nitrate poisoning 

  • Parasite outbreak 

Places to look for further information: 

The Dairy Vet Team
Previous

Too much nitrate can be nasty!
Next

The sometimes silent threat…