Heat Stress Management in Broilers and Production Improvement Strategies ( April–September in Pakistan)

Heat stress remains one of the most critical challenges for broiler producers, especially in countries like Pakistan, where temperatures frequently exceed 40°C from April through September. This prolonged hot season, often coupled with high humidity and inconsistent electricity supply, puts enormous pressure on poultry farmers to maintain flock health, feed efficiency, and profitability. This article provides practical, climate-specific strategies to combat heat stress and enhance broiler performance, particularly during Pakistan’s harsh summer months.

Understanding Heat Stress in Pakistan’s Broiler Industry

Broilers are highly vulnerable to high environmental temperatures due to their fast growth rate, thick feathering, and limited sweat glands. In Pakistan’s central and southern regions (e.g., Punjab, Sindh, Multan, Bahawalpur, Hyderabad), daytime temperatures can rise to 42–48°C, often accompanied by high humidity after monsoon rains.

From April to September, birds show:

  • Open-mouth breathing and panting
  • Drastic reduction in feed intake (up to 20–30%)
  • Increased water consumption
  • Dehydration, poor immunity, and higher mortality
  • FCR deterioration and poor final body weights

Heat Stress Management Strategies for April–September in Pakistan

1. Environmental Control and Housing Adaptation

Tunnel Ventilation and Air Velocity

  • Use tunnel ventilation systems to pull hot air out and cool air in.
  • Recommended air velocity:
  • 2.5–3.0 m/s (above 21 days of age)
  • Up to 3.5 m/s for older birds (35+ days)

Evaporative Cooling Pads and Foggers

  • Install cooling pads on the inlet side and use high-pressure fogging systems to lower shed temperature by 5–8°C.
  • Ensure pads are cleaned every 10–15 days during dusty months (May–June).

Insulation and Orientation

  • Use PUF-insulated roofing or reflective paint to reduce heat gain.
  • Houses should be built east–west facing to minimize direct sunlight.

2. Feeding and Water Management

Feeding Adjustments

  • Offer feed during cooler hours:
  • 5:30–8:00 AM and 6:30–8:30 PM
  • Temporarily reduce feed by 5–10% during peak heat (12–5 PM), then compensate at night.

Feed Quantity Example (Near Market Age):

  • Feed approx. 95–105 grams per session, twice a day
  • Use pelleted, nutrient-dense feed to maintain intake with smaller quantities

Water Supply and Electrolytes

  • Water should be below 25°C; bury pipelines or shade overhead tanks
  • Supplement with:
  • Electrolytes: Na+, K+, Cl−
  • Vitamin C: 200–300 mg/kg feed or via drinking water
  • B-complex and Anti-Stress mixtures during severe spells

3. Production Improvement Strategies for Pakistani Conditions

A. Genetic Selection

  • Use heat-resilient breeds like Ross 308 or Cobb, Arbor Acre, which perform better in South Asian environments.
  • Farms in Faisalabad and Lahore have reported up to 7% lower mortality with proper breed selection during June–August.

B. Nutritional Strategies

  • Reduce crude protein by 1–2% during peak summer while maintaining essential amino acids (lysine, methionine).
  • Add enzymes (xylanase, phytase) and natural antioxidants (Vitamin E 200 IU/kg + Selenium 0.3 ppm) to improve gut health and reduce oxidative damage.

C. Stocking Density and Bird Comfort

  • Reduce stocking density by 10–15% in summer:
  • Maintain 0.75–0.90 sq ft/bird
  • Avoid overcrowding and excessive handling from 12:00 PM to 5:00 PM.

D. Health Management and Vaccination Scheduling

  • Use heat-stable vaccines and plan vaccinations early in the morning or after 6:00 PM.
  • Use herbal immunostimulants (e.g., Aloe vera extract, turmeric-based tonics) to support immunity.

E. Monitoring and Technology Use

  • Install temperature and humidity loggers with GSM alerts.
  • Use apps like Farmflo or Smart Poultry to record daily weights, FCR, and water/feed ratios.

Example – A Case from Multan (Summer Batch, 2023):

A 40,000-bird farm implemented heat stress management from April to September:

  • Measures Taken:
  • Tunnel ventilation + cooling pads
  • Feed at dawn and dusk
  • Electrolytes + Vitamin C daily
  • Lowered stocking by 10%
  • Results:
  • Avg. final weight: 2.30 kg (vs 2.05 kg previous year)
  • FCR improved from 1.76 to 1.64
  • Mortality reduced from 7.2% to 3.6%

Conclusion

In Pakistan, where April to September presents extreme heat challenges, proactive planning and climate-smart poultry management can protect bird health and sustain performance. Key practices such as early morning/late feeding, tunnel ventilation, optimal air velocity, and antioxidant-rich nutrition must be considered standard during the summer cycle. Producers who adapt their systems, upgrade housing, and apply science-based strategies can not only survive but thrive even in the harshest months of the year.

Dr Hamid Masood
DVM, M.Phil, PhD Microbiology
Technical & Sales Director