Don’t let flies compromise your youngstock health 

Fly control is crucial as flies can be a problem to all livestock, including calves, during the summer months. The two most common species found on farms are the stable, house and face flies. 

Why fly control matters

The impact of flies can be detrimental to animal health, productivity, and profitability. Flies feed on other animals’ bodily fluids, including: blood, tears, sweat, urine, and faeces. This deprives animals of essential minerals and nutrients.

In addition to nutrient loss, flies are a major nuisance. Animals waste energy trying to battle them off by stamping, kicking, or head throwing. This can lead to injuries for both the animals and the stockperson. This also means the animals devote less time to grazing and resting.

Diseases spread by flies

Flies act as carriers for several diseases:

• Summer mastitis: biting flies act as vectors, causing mammary gland infections in cattle.

• Pink eye  (Keratoconjunctivis): generally spread by flies by feeding on sweat and tears.

• Blue tongue: the virus is spread by midges (Culicoides genus).  

Practical fly control measures on your farm

Improve hygiene

Flies thrive in dirty, damp environments. Their life cycle takes around 21 days, so it’s important to break the cycle by reducing breeding grounds.

Housed	Grazed
Keep bedding as clean and dry as possible. Regularly clean out pens and take the muck away from the area.	Avoid grazing near to water courses and wet fields.
Keep housing well drained and ventilated.	Ideally graze in breezy areas to keep the fly population down
Keep water troughs clean and algae free.
Remove soiled feed from troughs.
Ensure milk feeding utensils are cleaned and dry after every use.

Use fly control tools

There are many tools available for fly control in sheds, for example:

• Sticky glue rolls,

• Electric fly zappers

• Fly traps (only work in direct sunlight, these can be useful to use in paddocks).

There are many chemical sprays and insecticides also available. However, always check with your vet and supplier before using these products.  

Are fly products safe for calves?

Yes, but only certain products. Always talk to your vet about what is safe for different age groups. Follow the manufacturer’s guidelines carefully, especially regarding how long to wait before reintroducing animals to treated areas.

Garlic supplementation as a natural repellent

A garlic lick is a great way to provide animals with a fly repellent as well as their necessary minerals and vitamins whilst at grass. With garlic supplementation there are different sources available in the form of oil, salts, and powders etc. It is important to note that not all garlic is equal.

Garlic isn’t the most palatable feed therefore a lick with a suitable molasses content is vital alongside the correct level of garlic to achieve best intakes. Addition of high magnesium levels will reduce intakes. This means a dual-purpose magnesium and garlic bucket may not succeed enough intakes to cover for flies, milk fever or grass tetany. 

Additional benefits of garlic

Research shows garlic offers more than fly control. It is also has:

• Antibacterial, antifungal, and antioxidant effects in animals (Ogbuewu et al.,2019).

• Reduced faecal egg counts and greater weight gain in sheep (Curry and Whitaker, 2010 and Hasan et al., 2015)

• Increased rumen microbial protein synthesis in sheep (Mahmoud and Salah, 2017; Zhong et al., 2019; Zhu et al., 2021)

• Lower methane emissions. Some compounds found in garlic can inhibit the microbiome producing methane in the rumen (Dey et al., 2021)