Summer Horse Care: Flies, Heat, and Sun Protection

Summer Isn't Just Sunshine and Trail Rides

For a lot of riders, summer is the best season - long days, dry footing, and endless trail riding opportunities. But summer also brings a unique set of challenges that can make your horse miserable if you're not prepared. Relentless flies, dangerous heat, dehydration risks, and even sunburn can turn the best season into a stressful one for your horse.

The good news is that managing summer challenges is mostly about preparation and routine. Get your systems in place early in the season, and both you and your horse can actually enjoy the warm months.

Heat Stress: The Silent Summer Danger

Horses generate enormous amounts of internal heat during exercise - they're essentially 1,000-pound furnaces with a less efficient cooling system than humans. In hot, humid conditions, their ability to dissipate heat through sweating can be overwhelmed, leading to heat stress or, in severe cases, heat stroke.

Recognizing Heat Stress

• Excessive sweating followed by lack of sweating (anhidrosis - a serious condition)
• Elevated respiratory rate - rapid, shallow breathing that doesn't slow down with rest
• Heart rate that stays elevated (above 60 BPM) for more than 30 minutes after exercise
• Lethargy, stumbling, or disorientation
• Rectal temperature above 103°F (39.4°C) - above 105°F (40.5°C) is a veterinary emergency
• Dark, concentrated urine or reduced urination

Emergency Cooling

If your horse shows signs of heat stress:

1. Stop all exercise immediately and move to shade
2. Apply large amounts of cold water over the entire body, focusing on the large blood vessels along the neck, between the hind legs, and under the belly
3. Scrape the water off and reapply. Leaving warm water sitting on the skin can actually trap heat. The scrape-and-reapply cycle is critical.
4. Offer small amounts of cool (not ice-cold) water to drink
5. Fan the horse if possible to aid evaporative cooling
6. Call your veterinarian if the horse doesn't improve within 15-20 minutes or if rectal temperature exceeds 105°F

Prevention Strategies

• Ride early or late - Exercise during the cooler parts of the day. Early morning and late evening are best. Avoid midday rides in extreme heat.
• Acclimatize gradually - Horses need 2-3 weeks to adapt to hot conditions. Don't suddenly increase intensity when a heat wave hits.
• Monitor the heat index - Temperature plus humidity. When the combined number exceeds 150, reduce exercise intensity. Above 180, only light exercise at best.
• Provide shade - Run-in shelters, trees, or shade structures in pastures and paddocks
• Electrolytes - Supplement electrolytes for horses in regular work during hot weather. Offer plain water alongside electrolyte-treated water so the horse can choose.

Hydration: More Important Than You Think

A horse drinks 5-10 gallons of water per day under normal conditions. In hot weather or during exercise, that can double or more. Dehydration contributes to colic, poor performance, and heat stress.

Ensuring Adequate Hydration

• Fresh, clean water always available - Scrub water troughs weekly in summer to prevent algae and bacterial growth
• Check water temperature - Horses may drink less if water is too warm. Insulated tanks or shaded troughs help. Adding ice can encourage drinking on very hot days.
• Multiple water sources - In large pastures, ensure water is accessible without a long walk. Dominant horses may guard single water sources.
• Salt - Provide free-choice salt blocks or loose salt year-round. Salt stimulates thirst and promotes adequate water intake. Loose salt is consumed more readily than blocks.

The Skin Pinch Test

To check hydration, pinch a fold of skin on the horse's neck or shoulder. In a well-hydrated horse, the skin snaps back immediately. If it takes 2+ seconds to flatten, the horse may be dehydrated. This test isn't perfectly accurate (older horses and thin horses may have slower skin turgor regardless), but it's a useful quick check.

Fly Control: The Summer-Long Battle

Flies aren't just annoying - they cause real health problems. Stable flies bite and draw blood, face flies transmit eye infections, horn flies concentrate on the back and sides, and bot flies lay eggs that become stomach parasites. An effective fly control program uses multiple strategies simultaneously.

Environmental Management

• Manure management - Clean stalls daily. Remove pasture manure at least twice weekly. Flies breed in manure, and reducing breeding sites is the most effective single intervention.
• Standing water elimination - Dump any containers holding stagnant water. Fix leaky faucets. Mosquitoes and certain flies breed in standing water.
• Fan installation - Fans in barns and run-in shelters create air movement that flies can't navigate. Most flies can't fly in wind speeds above 5 mph.
• Compost properly - A properly managed hot compost pile kills fly larvae. An unmanaged manure pile is a fly factory.

Physical Barriers

• Fly masks - Protect eyes and ears from flies. Check fit daily - they shouldn't rub or obstruct vision. Remove at night to prevent moisture buildup.
• Fly sheets - Lightweight mesh blankets that cover the body. Particularly helpful for horses with sweet itch (Culicoides hypersensitivity).
• Fly boots/leg wraps - Protect lower legs from stomping injuries caused by relentless fly activity

Chemical Control

• Fly sprays - Pyrethrin-based sprays provide temporary relief. Reapply as directed. Oil-based sprays last longer than water-based.
• Spot-on treatments - Longer-lasting than sprays. Applied to specific areas.
• Feed-through fly control - Products added to feed that pass through the digestive system and prevent fly larvae from developing in manure. Most effective when all horses on the property use them.
• Fly predators - Tiny parasitic wasps that kill fly pupae in manure. Released monthly during fly season. They don't sting or bother humans or horses. An excellent biological control method.
• Fly traps - Various trap styles catch adult flies. Position away from where horses are kept (you want to attract flies away from horses, not toward them).

Sunburn and Sun Protection

Horses can and do get sunburned, particularly on pink-skinned areas like white blazes, pink noses, and areas with thin or white hair.

At-Risk Horses

• Horses with white facial markings, especially pink noses
• Paint and pinto horses with extensive white areas
• Cremello and perlino horses (double dilute genes producing pink skin)
• Gray horses as they age and their skin becomes more exposed
• Any horse with pink skin around the eyes

Protection Methods

• Fly masks with UV protection - Many fly masks include UV-blocking fabric. Choose these for horses with pink skin on the face.
• Equine sunscreen - Apply zinc oxide-based sunscreen (human baby sunscreen works) to pink noses and other exposed areas. Reapply every few hours if possible.
• Shade access - The simplest protection. Ensure pastures have shade structures or trees.
• Turnout timing - Turn at-risk horses out in the evening and bring in during peak UV hours (10 AM-4 PM) during summer.

Hoof Care in Summer

Summer presents its own hoof challenges. Dry conditions can cause cracking and brittleness, while frequent hosing and wet-dry cycling weakens hoof walls.

• Maintain farrier schedule - Don't extend intervals just because your horse seems fine. Hooves still grow and need regular attention.
• Hoof conditioner - In dry climates, a quality hoof moisturizer helps prevent cracking. Apply to the hoof wall and sole.
• Avoid hosing hooves constantly - Repeated wet-dry cycles soften and weaken hoof walls. If you hose down your horse to cool off, that's fine, but don't drench the hooves multiple times daily.
• Provide firm footing - Soft, wet footing in summer can contribute to thrush. Ensure dry areas are available.

Adjusting Feed and Nutrition

Horses may eat less in extreme heat, similar to how most of us lose appetite in a heat wave. Compensate by:

• Offering hay during cooler parts of the day when appetite is higher
• Ensuring pasture grass quality - summer heat can reduce nutritional value of grass
• Adding electrolytes for horses in work
• Monitoring body condition regularly and adjusting feed as needed
• Soaking hay or offering hay cubes/beet pulp to increase water intake through feed