After the Beginning of Autumn, the weather gradually cools. Flocks that have just reached peak production during the summer heat generally have some degree of weight deficit. How to remedy this after the Beginning of Autumn through management, nutrition, and other means is a question we all need to consider.
I. Management measures: The core goals are to ease residual stress, improve comfort, restore feed intake, and promote weight gain.
1, Refined environmental control to stabilize the microclimate:
Goal: Ensure sufficient feeding time and appropriate light intensity (10-20 lux, just enough for the chickens to see feed and water).
Laying hens: Keep the duration and intensity of lighting stable (unless increased production needs to be stimulated, in which case this should still be done according to a program). Avoid reducing feeding by shortening the lighting period.
Grower pullets/replacement pullets: Strictly control lighting according to body weight and age requirements to ensure that sexual maturity and physical maturity develop in sync.
Objective: Ensure air quality (no ammonia odor or dust), maintain relative humidity (45-65%), and avoid excessive air speed causing the chickens’ perceived temperature to be too low.
Focus: Increase minimum ventilation (especially when temperatures are low) to ensure fresh air reaches all areas of the poultry house evenly. During low-temperature periods in the early morning and evening, the inlet area may be reduced appropriately (but do not close the inlets), or the frequency of fan operation may be lowered. When temperatures are high at midday, increase ventilation to remove moisture and excess heat. Prevent cold drafts from blowing directly onto the chickens.
Temperature: Avoid renewed heat stress caused by the “autumn tiger,” but take even greater care to prevent cold stress in the early morning and evening and during sudden temperature drops (the most common disease-triggering factor after the Start of Autumn). Maintain the optimal temperature range according to the chickens’ age/stage (refer to the temperature control curve for brooding and rearing chickens; laying hens are typically 18-28°C). When gradually removing cooling equipment (such as evaporative cooling pads and misting systems), ensure a smooth transition. Take particular care to prevent drafts, especially cold drafts at night.
Ventilation: The day-night temperature difference increases in autumn, so ventilation management needs to be more precise.
Lighting: Follow the correct lighting program. When discontinuing midnight supplementary lighting for night feeding, do not stop it all at once. Instead, reduce the lighting time by 15 minutes per week until it is eliminated.
Maximize feed intake:
Increase feeding frequency/time: Provided the feed remains fresh (to prevent mold), feeding frequency may be increased appropriately, or each feeding period may be extended (to ensure the chickens have enough time to finish the feed).
Empty-trough management: Keep the feed lines clean. Allow a reasonable empty-trough period each day (1-2 hours) to stimulate appetite, ensure feed freshness, and allow the chickens to eat the fines at the bottom of the trough, promoting balanced nutrient intake.
Monitor drinking water: Ensure it is plentiful, clean, and at a suitable temperature (water that is too cold or too hot can affect drinking). Check whether the water pressure at the end of the water line and the nipple drinker flow rate are normal. Clean water is essential for ensuring feed intake and digestion.
Adjust feeder height/depth: Ensure the feed pan is at a suitable height so the chickens can peck at the feed easily without wasting it. Keep the feed layer at a moderate thickness.
Reduce stressors: Keep work procedures consistent (feeding, inspections, manure removal, etc.), handle birds gently, and reduce sudden noises or disturbances.
Strengthen weight monitoring and make adjustments:
Severely underweight (more than 10% below target): This indicates poor overall flock condition and requires a more aggressive nutritional recovery plan (see the nutrition section).
Uneven weight distribution (high variability): This indicates intense competition within the flock, with some weaker birds not eating enough. Check whether there is sufficient feeding space (feeder space and drinking space) and whether weaker birds need to be separated and fed. Reduce stocking density, ensure access to drinking water, improve feed palatability, and, if necessary, separate weaker birds for individual care.
Regular weighing: Especially for replacement pullets and flocks before the onset of lay. After the Beginning of Autumn, increase weighing frequency (at least once a week), weighing a sufficient number of randomly selected birds each time (more than 5% of the birds).
Analyze deviations:
Individual selection (for replacement pullets/pre-lay flocks): Clearly undersized or slow-developing chickens can be selected and moved to a dedicated “weaker birds” housing area for more intensive management and feed with a higher nutrient concentration until they reach the target body weight, then returned to the main flock.
Reduce stocking density: Flocks that have experienced summer heat stress are relatively weaker. In autumn, if conditions permit, appropriately reducing stocking density (for example, reducing the number of birds kept by 5-10%) can significantly reduce competition within the flock, improve ventilation, and help each bird recover and grow.
Strict biosecurity and health monitoring:
Autumn is a high-incidence season for respiratory diseases. Cold stress can trigger various viral and bacterial diseases (infectious bronchitis, infectious laryngotracheitis, rhinitis, avian influenza, Mycoplasma, etc.). Be sure to strengthen disinfection procedures (especially for ventilation systems and personnel/vehicle access routes), personnel isolation, and monitoring of vaccine effectiveness, and administer booster vaccinations promptly.
Closely monitor the flock’s mental state, breathing, and droppings to identify problems early.
Continue monitoring drinking water quality and mycotoxin levels in feed (pay particular attention to moisture and mold risks in newly harvested autumn corn and soybean meal).
II. Nutritional remedial measures: The focus is on increasing the energy and digestible nutrient concentration of feed, enhancing digestion and absorption, promoting tissue repair, and supporting weight gain.
Core strategy: Increase the energy concentration of feed
Add fat: This is the most direct and effective method! Add 1.5% - 3% high-quality vegetable oil (soybean oil, corn oil, palm oil, etc.) or animal fat (fish oil, lard; pay attention to quality) to the feed. Fat has the highest energy value (more than 2.25 times that of carbohydrates), has a low heat increment, and is readily utilized. Adding a high-quality emulsifier can improve fat digestibility (especially for chicks and weak birds). Increase the amount gradually, ensure thorough and even mixing, and prevent rancidity.
Reduce fiber content: Temporarily lower the crude fiber level in the feed (for example, reduce the amount of bran) to reduce digesta volume and the feeling of fullness, allowing the chickens to consume more concentrated, high-energy feed.
Use high-energy ingredients: If possible, use high-energy, easily digestible ingredients such as extruded corn and extruded soybeans in the compound feed.
Problem: Reduced feed intake during the hot summer months is the main cause of weight loss. Although feed intake will naturally recover after the Start of Autumn, naturally increased feed intake alone (which may only recover by 80-90%) is not enough to make up for the weight loss quickly; the feed needs to contain more energy per unit of weight.
Measures:
Optimize protein and amino acid levels to improve utilization:
Ensure a balance of essential amino acids: While increasing protein levels (especially for pullets and hens in early lay), it is more important to ensure that the levels of several essential amino acids (lysine, methionine, tryptophan, and threonine) meet or slightly exceed recommended standards. They are key limiting factors for chicken growth, feather development, muscle development, and egg protein synthesis. Using high-quality animal protein sources (fish meal, meat and bone meal) or synthetic amino acids (methionine, lysine, and threonine) to precisely balance the amino acid profile is more efficient than simply increasing crude protein content.
Improve protein (amino acid) digestibility: Selecting highly digestible protein ingredients (such as dehulled soybean meal and fish meal), using protease additives, and ensuring a sufficient proportion of high-quality protein in the feed help restore body weight and support tissue growth.
Problem: Insufficient protein deposition caused by the dog days of summer (especially the development of muscles and the reproductive system) persists even when body weight is close to the target.
Measures:
Note: Simply increasing the crude protein level is not the best approach. It may increase the burden on liver and kidney function (which may already have been damaged by high temperatures), and may also reduce palatability or cause diarrhea. Precise amino acid balance is the top priority.
Strengthen the supply of vitamins and trace elements:
Double the addition of compound vitamins: Add extra high-quality multivitamins to the feed (especially VC, VE, VD3, VB1, VB2, VB6, niacin, biotin, etc.). The amount added may be 150%-200% of the conventional amount (or even higher), for a period of time (such as 2-4 weeks). VE and VC are important antioxidants that help counteract stress damage, promote tissue repair, and improve immunity.
Appropriate electrolyte supplementation: Add an appropriate amount of compound electrolytes (containing potassium, sodium, bicarbonate, chlorine, etc.) to the drinking water to help regulate the body's osmotic pressure, alleviate dehydration, and maintain acid-base balance. Use for 3-5 days, then stop for a few days before using again.
Trace elements: Ensure an adequate supply of key trace elements such as zinc, selenium, manganese, and copper (selenium works synergistically with VE as an antioxidant). Organic trace elements may be used to improve absorption.
Pay particular attention to vitamin D3 and calcium-phosphorus balance: This is especially important for the skeletal development of replacement pullets and for laying hens. Ensure adequate effective vitamin D3 levels and an appropriate calcium-phosphorus ratio (replacement pullets 1.5-2.0:1, laying hens 5-6:1).
Issue: Heat stress consumes large amounts of vitamins (especially A, D, E, B vitamins, and C) and causes electrolyte imbalance.
Measures:
Improve intestinal health and promote digestion and absorption:
Add probiotics/prebiotics/synbiotics: Helps restore and maintain healthy gut flora, inhibit harmful bacteria, and improve nutrient utilization.
Add organic acids: lower gastrointestinal pH, inhibit harmful bacteria (such as E. coli and Salmonella), and promote digestive enzyme activity.
Add digestive enzymes, such as proteases, lipases, and amylases, to help break down nutrients, especially to address fat digestion problems after adding oil or fluctuations in feed quality.
Repair the intestinal mucosa: add substances such as glutamine, sodium butyrate, and yeast cell wall extract (β-glucan) to help repair damaged intestinal mucosa.
Prevent feed mold: strictly control raw material quality and use effective mycotoxin adsorbents/degraders to reduce toxin damage to the intestines.
Keep the litter dry (floor rearing): Damp, cold litter is an important contributing factor to digestive tract diseases (enteritis and coccidiosis).
Problem: Heat stress damages the intestinal mucosa and disrupts the gut microbiota, affecting digestion and absorption.
Measures:
III. Focus by stage:
Replacement pullets/young hens:
Primary goal: Make up the body weight deficit (reach or exceed the standard), ensure adequate skeletal development (meet the standard for shank length), and synchronize physical maturity with sexual maturity.
High energy (fat!), balanced and highly concentrated amino acids (lysine, methionine), enhanced vitamins (VD3, VE, B vitamins, etc.) and trace elements (correct calcium-to-phosphorus ratio) are the core of nutritional recovery. Increasing feeding frequency, extending lighting (if needed), and reducing stocking density are key management measures.
If body weight is severely inadequate, the rearing period can be temporarily extended, delaying the increase in lighting and transfer to another house (note the risk of delayed sexual maturity).
Early-laying flock:
Primary goal: rapidly gain weight to reach standard body weight, laying the physical foundation for peak egg production and sustained high production.
Maintain or slightly exceed the nutrient concentrations in peak-production feed (especially energy, protein/amino acids, and calcium). Focus on increasing added fat (1.5-3%) and balancing amino acids. Strengthen the supply of vitamins (especially VA, VD3, VE, VC, and the VB group).
Ensure feed intake and manage empty feeders properly.
Peak period/mid-to-late-stage laying hens:
Primary objectives: restore body condition depleted by overexertion, replenish energy reserves, extend the duration of peak production, and reduce mortality and culling rates.
Nutritional focus: Increase feed energy density (fats), ensure adequate amino acids (especially methionine), provide fortified levels of multiple vitamins (antioxidants, B vitamins, VD3, VE), and use high-quality calcium sources (such as coarse limestone powder).
Management focus: Maintain a stable environment, avoid cold stress, manage ventilation precisely, and reduce any form of additional stress.
Summary and key points:
Accurate assessment is essential: Understand the flock’s actual body condition (average body weight and body weight distribution) through weighing.
“High energy” is key to rapid weight gain: Adding high-quality oils and fats (1.5%-3%) to the feed is an immediately effective approach.
“Precision amino acids” are essential for efficient recovery: Ensuring a balanced and adequate supply of essential amino acids (lysine, lysine, methionine) is more effective and economical than simply increasing crude protein.
“Strengthening vitamins” is the foundation for repair: doubling the supplementation of multivitamins (especially VC, VE, VD3, and the VB group) is essential to combat stress damage and promote tissue repair.
“Promoting digestion” is a means of improving efficiency: use probiotics, enzyme preparations, and organic acids to improve intestinal health.
“Prevent cold stress and maintain stable ventilation” is the core of management: after the weather turns cool in autumn, preventing cold drafts (especially sneaky drafts) is more important than preventing heat stress. Precise ventilation management is essential.
“Control stocking density and promote feed intake” are everyday essentials: reduce stocking density, increase feeding frequency/time, and manage empty feeders properly.
“Group treatment” is more effective: select obviously weaker individuals and raise them separately, providing a higher-concentration diet.
Ongoing monitoring and adjustment: Weigh the animals again 1-2 weeks after implementing the plan to evaluate its effectiveness and adjust the strategy in a timely manner.