This special edition of CHICK-NEWS is sponsored by Ziggity Systems, innovators of poultry watering systems for nearly 50 years. In addition to updated USDA statistics on broiler and turkey production and exports information is provided on the new Ziggity Max6™ drinker and the basics of operating watering systems for broilers. 

Basic principles of physiology and flock management converge to achieve the genetical potential of current broiler strains irrespective of harvest weight. Care in selection, installation, operation and maintenance of watering systems contributes to optimal live bird parameters, quality, yield and returns to both contractor and integrator.  

1. How Broilers Regulate Water Intake

Birds drink when they are thirsty.  The hormonal and neural mechanisms involved in thirst have developed through the evolution of chickens over millennia. More recently intensive index selection for commercial traits favoring rapid growth and breast yield has influenced behavior and water requirement. The stimulus to drink is initiated by baroreceptors sensitive to blood pressure and osmoreceptors that respond to changes in the chemical composition of blood.  Thirst reflects the interpretation of signals received from receptors that are processed by centers in the brain that encourage drinking.

In contrast to mammals, chickens have two added complications in regulation of water intake. Heat is lost by evaporative cooling only from respiratory surfaces as skin is insulated by feathers. Avian kidneys are relatively inefficient, consistent with their reptilian ancestry.  The glomeruli, microscopic structures in the kidney responsible for filtration are less numerous than in mammals and are smaller and relatively inefficient, placing an additional burden on the neural and hormonal factors that regulate thirst.

When birds are subjected to high ambient temperature, respiratory rate increases to enhance evaporation of water from the surfaces of the trachea, pharynx and oral cavity. With the change in state from liquid to vapor, latent heat is lost, effectively cooling the bird. This process requires water drawn from the blood necessitating replacement from extracellular water. The resultant changes in blood composition stimulate thirst. Evaporative cooling results in increased water consumption by the flock that is evident when comparing water meter readings against ambient temperature.

With an understanding of factors that influence thirst, it is self-evident that simple rule-of-thumb formulas relating to flow-rate of nipple type drinkers are simplistic, meaningless and potentially counterproductive. Water intake by any flock is influenced by age, strain, growth rate and environmental conditions in the house. These include ventilation settings in relation to temperature, humidity and ammonia content of air. It is not possible to induce broilers to eat more than their physiological requirements by attempt to increase water intake through raising water pressure in drinker lines.

1. Water Use Compared to Actual Intake

It is important to distinguish between water use as measured by the volume of water passing through a house meter and the intake represented by the actual volume of water swallowed and hence ingested.  The difference between use and intake represents spillage. A drinker with an excessive discharge of water when activated by the bird will indeed satisfy thirst. It is inevitable that water that is not swallowed due to limitations of the capacity of the oral cavity will be spilled on to the litter. The ability of various substrates including wood shavings and rice hulls to absorb spillage is limited especially with the reality of leakage from imperfectly designed or operated nipples.

The rate of removal of water from litter is a function of the temperature and humidity in the house in relation to the operation of the ventilation system.  At humidity levels below 50 percent and with a minimum ventilation rate of 1cfm per pound body weight, excess moisture will be removed from litter and hopefully under the drinker lines where the flock congregates.  In the event of excessive spillage during drinking and any leakage from drinkers saturation of litter will occur. This is especially evident under conditions of high humidity coupled with low temperature or when suboptimal ventilation rates are applied to conserve gas.

1. Management of Watering Systems

Many within the chicken industry emphasize the importance of a high static-flow rate (excessive pressure to release water) from nipples, usually expressed as milliliters per minute. Simple values relating to age of a flock are essentially meaningless in the context of satisfying thirst.  A static flow rate does not correlate to the way in which a bird actually interacts with a nipple drinker. Chickens peck at trigger pins to receive a small release of water, most of which should be swallowed. Ideally the quantity of water ingested should be adequate to satisfy thirst but not so high that any appreciable quantity is spilled. Nipple drinkers should supply an adequate, but not excessive, quantity of water as the bird pecks at the trigger. This satisfies requirements for growth and prevents spillage on to litter.

Managing a watering system to achieve an undesirably high flow rate, causing excess spillage is analogous to working on a hot day in a garden and drinking from a hose. The flow rate from the nozzle will be too high in relation to the volume that can actually be swallowed over a few seconds. Although thirst is satisfied there is considerable spillage. This may be inconsequential standing on a lawn but in the context of broiler growing, spillage saturates litter in a poultry house with adverse effects on health and quality. 

The correct function of drinking systems should not be measured by static water flow rate but by dynamic release that conforms to the pattern of drinking conditioned  by volume of the oral cavity. The return over production costs for a flock is influenced by adequate water and feed intake and freedom from erosive intestinal and respiratory diseases, resulting in optimal growth and product quality.

1. The Consequences of Wet Litter

High moisture levels in litter extending to areas of saturation is problematic for broiler flocks. Wet bedding is invariably associated with respiratory, intestinal and skin conditions that detract from optimal growth and that compromise quality.

• Intestinal conditions that are adversely affected by wet or damp litter include coccidiosis and clostridial enterotoxemia (necrotic enteritis and hepatitis).  Appropriate control of litter moisture is extremely important in drug-free growing systems. Elimination of chemical feed-additives including antibiotics and coccidiostats presumes greater attention to management of ventilation and watering systems to prevent excess litter moisture. Feed additives used in conventional production suppress intestinal proliferation of Clostridium and block stages in the life cycle of coccidiosis parasites.

• Ammonia is liberated from damp and wet litter. This is the result of bacterial degradation of uric acid excreted by the flock. Ammonia irritates the respiratory mucosa exacerbating the effects of respiratory pathogens including infectious bronchitis and laryngotracheitis viruses.  There is ample evidence to show that flocks subjected to levels of atmospheric ammonia exceeding 25 ppm at bird’s head height for prolonged periods have lower growth rates and higher mortality than when reared at lower levels of atmospheric ammonia.

• Skin is adversely affected by wet litter and ammonia.  Proliferation of Clostridium spp. in damp litter contributes to gangrenous dermatitis. Wet litter with liberation of ammonia predisposes to “hock burn” and pododermatitis restricting growth rate and reducing the value of feet for export.

• Wet litter increases proliferation of Salmonella spp. and Campylobacter spp. These foodborne pathogens are ingested by the flock, colonizing the intestinal tract and coating feathers. This increases the level of fecal excretion, contaminating transport modules, scald tanks, defeathering and E-line equipment, contributing to potentially high levels of pathogens on products. Wet litter favors persistence and proliferation of bacterial foodborne pathogens reflecting adversely on compliance with USDA-FSIS standards. 

Selection and management of watering systems is integral to achieving optimum return from flocks and should be based on applying appropriate pressure settings and operation of ventilation installations.

Over the past ten years, broiler genetics has continued to evolve in ways that emphasize efficiency, growth rate and feed conversion. Birds achieve their target weight faster than ever, with less feed required per pound or kilo of produced weight. Concurrently, bird behavior has changed as well.  Field observations demonstrate that broilers drink more often compared to broilers from a decade ago.

Because of these behavioral changes, Ziggity developed the Max6™ line of poultry watering drinkers. Max6™ drinkers have newly optimized internal geometry which withstands the more frequent pecking behavior of modern birds in a way that mitigates spillage. This ensures that birds receive the water they need without oversaturating the litter and results in drier, healthier housing conditions and more consistent flock performance.

Additionally, the design of the Max 6™ drinker eliminates the need for catch cups facilitating natural heads-up drinking.  Elimination of catch cups maintains the bacterial integrity of a closed drinking system, preventing ingestion of accumulated and contaminated water that is potentially responsible for enteritis and colonization of the flock with foodborne pathogens.

Recognizing that growers incorporate a range of chemicals to decontaminate water systems and to remove biofilm, Ziggity has incorporated materials with enhanced chemical resistance to extend operational life. This will help maintain the functional integrity of the Max6™ drinker and prevent dripping. Leading to saturation of litter in the vicinity of drinker lines.

In launching the Max 6™ drinker, Rob Steiner, Vice President of Sales at Ziggity Systems stated, “We created a drinker to accommodate the bird’s evolved behavior, so flocks get the water they need without spillage.”  He added, “As the industry benefits from advances in broiler genetics, Ziggity watering technology has evolved to allow maximum growth rate while maintaining the quality of litter that has a direct effect on gut health, ammonia and the quality and market value of paws”.

Field evaluation has demonstrated the enhanced return from improved growth and feed conversion, low cull and mortality rates and enhanced paw revenue.

Ziggity Max 6™ drinkers can be used with all existing Ziggity systems or be retrofitted to competitor watering lines using a special- purpose saddle adapter.  This allows for the upgrade of existing installations at minimal cost.

The U.S. and international markets are served through appointed Ziggity Systems distributors who can provide technical assistance and field support.

For almost 50 years Ziggity Systems has pioneered poultry watering solutions and is the industry innovator developing a range of drinking systems for all types of commercial poultry

For further information contact Ziggity Systems Inc. www.ziggity.com or +1 (574) 825-5849 U.S. central time.

OVERVIEW

Total exports of bone-in broiler parts and feet during January-April 2025 attained 1,021,432 metric tons, 8.1 percent lower than in January-April 2024 (1,111,867 metric tons). Total value of broiler exports increased by 2.2 percent to $1,531 million ($1,498 million).

Total export volume of turkey products during January-April 2025 attained 57,399 metric tons, 16.0 percent less than in January-April 2024 (68,365 metric tons). Total value of turkey exports increased by 11.9 percent to $219.7 million ($196.3 million).

Unit price for the broiler industry is constrained by the fact that leg quarters comprise over 96 percent of broiler meat exports by volume (excluding feet). Leg quarters represent a relatively low-value undifferentiated commodity lacking in pricing power. Exporters of commodities are subjected to competition from domestic production in importing nations. Generic products such as leg quarters are vulnerable to trade disputes and embargos based on real or contrived disease restrictions. To increase sales volume and value the U.S. industry will have to become more customer-centric offering value-added presentations with attributes required by importers. Whether this will increase margins is questionable given the by-product contribution of leg quarters. A more profitable long-term strategy for the U.S. industry would be to develop products using dark meat to compete with and displace pork and beef in the domestic retail and institutional markets.

HPAI is now accepted to be a panornitic affecting the poultry meat industries of six continents with seasonal and sporadic outbreaks. The incidence rate and location of cases in the U.S. limits eligibility for export depending on restrictions imposed by importing nations

Uncertainty surrounding tariff policy is an added complication potentially impacting export volume in 2025. In the event of reduced exports leg quarters would be diverted to the domestic market resulting in a depression in average value derived from a processed bird.

EXPORT VOLUMES AND PRICES FOR BROILER MEAT

During January-April 2025 the National Chicken Council (NCC), citing USDA-FAS data, documented exports of 984,621 metric tons of chicken parts and other forms (whole and prepared), down 9.0 percent from January-April 2024. Exports were valued at $1,024 million with a weighted average unit value of $1,520 per metric ton.

The NCC breakdown of chicken exports for January-April 2025 by proportion and unit price for each category compared with the corresponding months in 2024 (with the unit price in parentheses) comprised:-

• Chicken parts (excluding feet)    95.2%; Unit value  $1,406 per metric ton   ($1,277)
• Prepared chicken                     4.1%; Unit value  $4,155 per metric ton   ($4,124)
• Whole chicken                         0.7%; Unit value  $1,562 per metric ton   ($1,630)
• Composite Total                  100.0%;  Av. value   $1,520 per metric ton  ($1,363)

The following table prepared from USDA data circulated by the USAPEEC, compares values for poultry meat exports during January-April 2025 compared with the corresponding months of 2024:-

                  COMPARISON OF U.S. CHICKEN AND TURKEY EXPORTS

                                    JANUARY-APRIL 2025 COMPARED TO 2024

BROILER EXPORTS

Total broiler parts, predominantly leg quarters but including feet, exported during January-April 2025 compared with the corresponding months in 2024 declined by 8.1 percent in volume but were up 2.4 percent in value. Unit value was 14.3 percent higher to $1,499 per metric ton.

During 2024 exports attained 3,251,000 metric tons valued at $4,689 million, down 10.5 percent in volume and down 1.1 percent in value compared to 2023. Unit value was up 10.7 percent to $1,442 per metric ton

Broiler imports in 2025 are projected to attain an inconsequential 67,000 metric tons (134 million lbs.) compared to 82,000 metric tons (180,000 million lbs.) in 2024

The top five importers of broiler meat represented 49.8 percent of shipments during January-April 2025. The top ten importers comprised 66.1 percent of the total volume reflecting concentration among the significant importing nations but with a decline in the importance of 8^th-ranked China.

Nations gaining in volume compared to the corresponding period in 2024 (with the percentage change indicated) in descending order of volume with ranking indicated by numeral were:-

4. Philippines, (+29%); 5. Canada, (+31%); 10.Ghana, (+50%); 11. Dominican Republic, (+29%) and 14. Haiti, (+5%)

Losses during January-April 2025 offset the gains in exports with declines for:-

1. Mexico, (-3%); 3. Taiwan, (-5%); 6. Guatemala, (-4%); Viet Nam, (-17%);                   8. China, (-53%); 9. Angola, (-19%) and UAE, (-4.3)

TURKEY EXPORTS

The volume of turkey meat exported during January-April 2025 declined by 16.0 percent to 57,399 metric tons from January-April 2024 but value was 12.3 percent higher to $220 million compared to January-April 2024. Average unit value was 33.7 percent lower to $2,833 per metric ton.

Imports of turkey products attained 15,000 metric tons (33 million lbs) in 2024 with a similar projection for 2025.

It is important to recognize that exports of chicken and turkey meat products to our USMCA partners amounted to $1,264 million in 2021, $1,647 million during 2022, $1,696 in 2023 and $653 million over the first four-months of 2025. It will be necessary for all three parties to the USMCA to respect the terms of the Agreement in good faith since punitive action against Mexico or Canada on issues unrelated to poultry products will result in reciprocal action by our trading partners to the possible detriment of U.S. agro-industries. This is especially important as Mexico has elected a new Presidenta and a Prime Minister of Canada.

The emergence of H5N1strain avian influenza virus with a Eurasian genome in migratory waterfowl in all four Flyways of the U.S. during 2022 was responsible for sporadic outbreaks of avian influenza in backyard flocks and serious commercial losses in egg-producing complexes and turkey flocks but to a lesser extent in broilers. The probability of additional outbreaks of HPAI over succeeding weeks appears likely and will intensify with fall migration of waterfowl Additional outbreaks affecting egg-production and turkey flocks will be a function of shedding by migratory and domestic birds and possibly free-living mammals and extension from dairy herds. Protection of commercial flocks at present relies on the intensity and efficiency of biosecurity including wild-bird laser repellant installations, representing investment in structural improvements and operational procedures. These measures are apparently inadequate to provide absolute protection, suggesting the need for preventive vaccination in high-risk areas for egg-producing, breeder and turkey flocks.

The application of restricted county-wide embargos following the limited and regional cases of HPAI in broilers with restoration of eligibility 28 days after decontamination has supported export volume for the U.S. broiler industry. Exports of turkey products were more constrained with plants processing turkeys in Minnesota, the Dakotas, Wisconsin and Iowa impacted.  The challenge will be to gain acceptance for vaccination based on intensive surveillance. It is now accepted that H5N1 HPAI is panornitic in distribution among commercial and migratory birds across six continents. The infection is now seasonally or regionally endemic in many nations with intensive poultry production, suggesting that vaccination will have to be accepted among trading partners as an adjunct to control measures in accordance with WOAH policy.

The live-bird market system supplying metropolitan areas, the presence of numerous backyard flocks, gamefowl and commercial laying hens allowed outside access, potentially in contact with migratory and now some resident bird species, all represent an ongoing danger to the entire U.S. commercial industry. The live-bird segments of U.S. poultry production represent a risk to the export eligibility of the broiler and turkey industries notwithstanding compartmentalization for breeders and regionalization to counties or states for commercial production.

Introduction

Photocatalytic oxidation (PCO) has extensive potential applications in the broiler industry. Genesis Air, located in Lubbock, TX has wide and unique experience in designing and installing their patented PCO technology in military installations and for commercial applications including airports, casinos, hospitals, auditoriums, greenhouses and restaurants.

Based on the laboratory and field trials, adoption of the technology appears both practical and cost-effective for specific components of the broiler production chain including hatcheries and processing plants. PCO technology is widely used in commercial HVAC installations to reduce airborne pathogens and to degrade volatile organic compounds in air by generating reactive oxygen species (ROS).

Principle of Photocatalytic Oxidation

Exposure of a photocatalyst such as titanium dioxide to ultraviolet light at a specific energy intensity and within a defined wavelength results in generation of reactive oxygen species (ROS) including hydroxyl radicals and superoxide ions, (Foster et al, 2011). These short-lived reactive oxygen species have the potential to destroy pathogens including bacteria, fungi and viruses in an environment even with high humidity, (Ahmadi et al, 2021). In addition, reactive oxygen species interact with volatile organic compounds resulting in their degradation, (Wu et al, 2021).  The decomposition of volatile organic compounds is substrate-specific with proven reduction of atmospheric nitrous oxide, acetaldehyde, ammonia, formaldehyde and other organic compounds, (He et al, 2002).

A UV spectrum lower than 180 nm, as used in non-photocatalytic ‘air-purifiers’, generates ozone that may be potentially harmful to respiratory tissue at high concentration in confined spaces with limited air exchange.  In contrast, most photocatalytic installations are innocuous and are environmentally acceptable.

Genesis Air Inc.-Innovators in PCO Technology

Genesis Air manufactures engineered solutions utilizing their extensive experience in application of photocatalytic oxidation to reduce airborne volatile organic compounds and pathogens.  Equipment is currently installed in 25 airports, 200 healthcare and laboratory facilities, 75 educational institutions and 70 facilities` operated by federal, state and local governments.

The current range of Genesis Air equipment extends from domestic units with an air flow rate of 65 cfm to commercial units handling up to 500,000 cfm.  Genesis Air uses modular designs with increasing numbers of panels in free-standing units or as an array in air ducts and air handling installations.  Hospitals with Genesis Air equipment installed in critical care areas have achieved measurable reductions in average SIR (Standard Infection Rate) with MRSA. This success, as measured by a reduction in infection rates, suggests beneficial application in hatcheries.

Scientific Evaluation of Genesis PCO Technology

Structured scientific studies document evaluation of Genesis Air equipment with respect to inactivation of pathogens that are encountered in poultry production facilities including hatcheries and in areas where personnel congregate including changing and break rooms.

• During 2006, the U.S. Army, Dugway, UT. Proving Ground conducted an evaluation of the Genesis Air 2002 B unit with specific reference to Aspergillus niger.  Using a standard protocol and a test installation the PCO unit significantly reduced the quantum of spores introduced into the inlet air stream by an average of 93.5 percent.

In a separate evaluation, it was determined that the Genesis Air 2002 module was able to remove or neutralize more than 98 percent of airborne spores of Bacillus subtilus var. niger transiting the chamber The filter stage of the system that excluded particles greater than 3 microns in diameter was responsible for removal of 50 percent of airborne bacterial spores.

• Evaluation of a Genesis Air 2002 B Unit by RTI International during 2008 demonstrated high inactivation efficiency against Staphylococcus epidermidis (99.9 percent) and Mycobacterium parafortuitum (88.7 percent)..  The RTI evaluation was conducted at the request of the Government Scientific Source arising from concern over biowarfare agents.  RTI operates a dynamic microbiological test chamber allowing introduction of bioaerosol suspensions of challenge microorganisms with sampling of both upstream and downstream airflow at 1,800 CFM.

• RTI International conducted an evaluation of Genesis Model 2008 B3 unit during 2012.  Applying a standard protocol using the RTI dynamic microbiological test chamber the inactivation efficiency against Staphylococcus epidermidis attained 84.6 percent with a flow rate of 2,000 CFM.  The inactivation efficiency for Bacillus atrophaeus was 65.6 percent reflecting the durability of Bacillus spores.  This RTI evaluation was conducted at the request of Genesis Air, Inc.

•  LMS Technologies, Inc., Bloomington, MN., conducted an evaluation of a Genesis module against MS2 bacteriophage (ATCC 15597-B1).  The test was conducted in a horizontal ASHRAE 52.2 stainless steel test duct.  Three replicate assays were conducted with an efficiency ranging from 99.2 percent to 99.7 percent in reducing challenge virus in the downstream airflow. This evaluation demonstrated more efficient inactivation of the bacteriophage than in the 2008 RTI assay due to improved equipment to aerosolize the test virus.

• LMS Technologies conducted a chamber test against three biological contaminants during 2023.  Inactivation in excess of 99.9 percent was achieved against Staphylococcus epidermis, MS2 bacteriophage and Escherichia coli. The evaluation demonstrated similar levels of inactivation against the three organisms using Genesis Air RGS, RGS- Mini and Kestrel models. The evaluation was conducted on the three PCO units to obtain U.S. FDA certification.

Evaluations conducted by independent and reputable research agencies and institutions confirm the effectiveness of Genesis Air photocatalytic oxidation technology to remove bacterial, fungal and viral pathogens from airstreams under controlled experimental conditions. 

Within the context of egg storage, operation of hatcheries and transport of chicks, Genesis Air, Inc. photocatalytic oxidation technology represents a potential to enhance hatchability, the viability of chicks and their subsequent production.

Potential Applications of PCO Technology in the Poultry Industry

• Egg storage areas in breeder-level and commercial hatcheries to suppress levels of bacteria and fungi to improve hatchability.  Operation of Genesis Air equipment within HVAC installations or as free-standing units may reduce bacterial and fungal contamination in chick service areas based on evaluations conducted by third-party institutions.

• Installation of Genesis Air units in breakrooms and change areas may benefit workers and potentially reduce absenteeism in the event of reemergence of COVID or to suppress seasonal influenza.

• Inactivation of pathogens during breeder and commercial-level chick transport using vehicle-operated Genesis Air units may contribute to improved livability after placement.

• Table-egg packing and breaking plants including grading, processing and storage areas, break rooms and offices

References

Ahmadi, Y. et al. Recent Advances in Photocatalytic Removal of Airborne Pathogens in Air. The Science of the Total Environment 794 (2021) doi.org/10.1016/j.scitotenv.2021.148477

Foster, H. et al. Photocatalytic Disinfection Using Titanium Dioxide: Spectrum and Mechanism of Antimicrobial Activity. Appl Microbiol Biotechnol 90,1847-1868 (2011) doi.org/10.1007/s 00253-011-3213-7

He, F. et al. Photocatalytic Air Purification Mimicking the Self-Cleaning Process of the Atmosphere. Nature Communications.12:2528 (2021) doi.org/10.1038/s 41467-021-22839-0

Wu, J. et al. Ultraviolet Photocatalytic Technology for Indoor Volatile Organic     Compound Removal: A Critical Review with Particular Focus on By-product Formation and Modeling. J. Hazardous Materials 421 (2022) doi.org/10.1016/j hazmat.2021.126766

Contact

For additional information and to consider specific applications contact Dan Briggs, CEO at Genesis Air, dbriggs@genesisair.com or (806) 786 9115.     

On May 16^th 2024 the USDA-Economic Research Service released updated production and consumption data with respect to broilers and turkeys, covering 2024, a projection for 2025 and a forecast for 2026.

The 2025 projection for broiler production is for 47,512 million lbs. (21.596 million metric tons) up 1.1 percent from 2024. USDA projected per capita consumption of 101.8 lbs. (46.3 kg.) for 2025, up 0.8 percent from 2024. Exports will attain 6,578 million lbs. (2.940 million metric tons), 2.2 percent below the previous year.

The 2026 USDA forecast for broiler production will be 48,100 million lbs. (21.864 million metric tons) up 1.2 percent from 2025 with per capita consumption up 0.8 lb. to 102.6 lbs. (46.6 kg). Exports will be 1.4 percent higher compared to 2025 at 6,670 million lbs. (3.031 million metric tons), equivalent to 13.9 percent of production.

Production values for the broiler and turkey segments of the U.S. poultry meat industry are tabulated below:-

Source: Livestock, Dairy and Poultry Outlook released May 16^th 2025

The May USDA report updated projection for the turkey industry for 2025 including annual production of 5,121 million lbs. (2.326 million metric tons), down 5.1 percent from 2024. Consumption in 2025 is projected to be 13.1 lbs. (6.0 kg.) per capita, down proportionately by 5.1 percent from the previous year. Export volume will attain 420 million lbs. (190,900 metric tons) in 2025. Values for production and consumption of RTC turkey in 2025 are considered to be realistic, given year to date data, the prevailing economy, variable weekly poult placements, production levels, reduced losses from HPAI and inventories consistent with season.

The 2026 forecast for turkey production is 5,040 million lbs. (2.291 million metric tons) up an optimistic 3.7 percent from 2025 with per capita consumption up 0.8 percent to 13.4 lbs. (6.1 kg). Exports will be 3.6 percent higher than in 2025 to 435 million lbs. (197,728 metric tons) equivalent to 8.6 percent of production.

Export projections do not allow for a breakdown in trade relations with existing major partners including Mexico, Canada and China nor the impact of catastrophic diseases including HPAI and vvND in either the U.S. or importing nations.

Based on the ubiquitous presence of domestic pigeons (Columba livia)  in feed storage, mixing and transport facilities and on poultry farms, a series of studies was performed to investigate the susceptibility of the species to H5N1 avian influenza clade 2.3.4.4b.  Variable doses of virus were administered to pigeons confirming resistance to other than high levels of virus.  Pigeons did not demonstrate clinical signs after infection and did not transmit virus to either contact pigeons or chickens.  Low levels of viral RNA were identified in tissues from directly inoculated pigeons but absent any obvious histologic lesions.

Based on the laboratory and contact studies, pigeons are regarded as an unlikely source of avian influenza and do not pose a significant threat of zoonosis. 

DiGenova, C. et al, Pigeons Exhibit Low Susceptibility and Poor Transmission Capacity for H5N1 Clade 2.3.4.4b High Pathogenicity Avian Influenza Virus.  bioRxiv doi.org/10.1101/2025.05.02.651910

This special edition of EGG-NEWS is intended to update subscribers with recent events relating to HPAI with commentary. The past week was dominated  by the as yet single case of HPAI in a commercial farm in Brazil and the implications arising from the event. A case  of HPAI in a large egg-production complex in Arizona in late May suggests that infection may be introduced onto farms from sources other than seasonally migrating waterfowl that are currently in their breeding areas. 

The messages to be conveyed in this edition are:-

•   HPAI should be recognized as a panornitic. This dictates radical changes to traditional restraints on international trade in poultry and products. Import regulations should be amended to conform to WOAH principles and standards including regionalization, compartmentalisation, vaccination and surveillance
•   HPAI is endemic in the U.S. especially impacting  regions corresponding to the four migratory flyways.
•   Biosecurity, however stringent does not provide absolute protection
•   Vaccination against H5 avian influenza is required as an adjunct to biosecurity for U.S.egg-producing and turkey flocks in high-risk areas, subject to surveillance and certification of freedom from infection at the time of harvest or shipment of eggs

A recent publication* evaluated transmission of H5N1 influenza among dairy cattle in the U.S.  The stochastic model based on 36,000 dairy herds in the continental U.S. attempted to quantify the extent of infection.  As of January 2025, when the article was submitted for peer review, the authors concluded that the infection is under-reported and that outbreaks will increase in Arizona and in Wisconsin.  The model suggests continuing cases associated with movement of dairy cattle coupled with inadequate programs of surveillance and restriction of transport.

Persistence of bovine influenza H5N1 in dairy cattle represents a danger to the poultry industry as confirmed by the 2024 outbreak of highly pathogenic avia influenza (HPAI) in western Michigan and the possibility of cases in Colorado and more recently in Arizona.  Failure to control and suppress bovine influenza will represent an ongoing risk to egg producers given movement of personnel between dairy herds and poultry flocks.  Common feed mills with non-dedicated delivery vehicles represents a risk of cross-industry infection. Proximity of large dairy and poultry farms could result in transmission of HPAI given the possibility of aerogenous spread of virus from large dairy installations to power-ventilated egg-production complexes.

*Rawson, T. et al A mathematical model of H5N1 influenza transmission in U.S. dairy cattle. Nature Communications doi.org10.1038/s41467-025-59554-z April 2025.

A recent article in the peer-reviewed journal Vaccines evaluated immunogenicity and efficacy of commercially available vaccines against highly pathogenic avian influenza virus, strain H5N1 in commercial geese raised for slaughter.  In general, an immune response was elicited by all vaccines evaluated, but durability of immunity was dependent on the type of the initial vaccination and the sequence of subsequent booster doses. Challenge under controlled conditions showed protection from clinical disease. Vaccination did not establish sterile immunity, although viral shedding was significantly lower compared to unvaccinated controls.

• Subunit vaccines containing H5 hemagglutinin antigen elicited seroconversion after a single dose and provided clinical protection. 
• A viral vector vaccine delivering genes encoding for H5 antigen resulted in a protective level of antibodies but required a booster for complete protection, and with some viral shedding following challenge.
• An RNA vaccine delivering nucleic acid sequences to stimulate antibody offered full clinical protection following initial vaccination with a booster.
• An inactivated oil emulsion vaccine containing native viral proteins stimulated seroconversion after a single dose but a booster enhanced antibody titer and protection.

The authors concluded that vaccination of geese, irrespective of the type of vaccine administered provided clinical protection and reduced viral excretion.  The results confirmed that vaccines could be incorporated into a program of HPAI prevention for geese that are highly susceptible and represent a significant industry in eastern Europe. 

The need for surveillance of vaccinated flocks was stressed to confirm attainment of protective levels of circulating antibody. Sequencing viral isolates is necessary to detect possible mutations associated with application of vaccination, recommOended as an adjunct to biosecurity measure to protect growing geese and presumably other commercial poultry species.

Despite the fact that migratory waterfowl are now established in their summer breeding grounds, outbreaks of highly pathogenic avian influenza (HPAI) persist.  The latest case in Maricopa County, AZ, involving a complex of 2.3 million hens indicates the persistence of infection.  Sequencing of the implicated virus will determine whether it is an avian-related D1.1 or a cattle B3.13 strain that will provide evidence of the source and route of infection.  The outbreak in Arizona was preceded by an April 30^th case involving 0.6 million hens in Aurora, SD. 

The severe losses that have occurred in 2025 to date include 33.2 million egg-producing hens on 60 farms or complexes. The incidence rate has obviously declined over the past three months but diagnosed outbreaks persist.  Growing turkeys are affected along with individual and obviously under-reported cases in backyard flocks.  Isolation of H5N1 avian influenza virus from live bird markets confirms the presence of undiagnosed supply flocks. Based on the absence of reports there is no certainty that USDA-APHIS is conducting traceback investigations to identify the source farms supplying live markets along the Atlantic seaboard.  The APHIS dashboard relating to detection of highly pathogenic avian influenza in wild birds updated on May 13, indicates isolation of H5N1 virus with a Eurasian genome from diverse states involving both waterfowl, black vultures  during Q1 and swallows during January.

Outbreaks among commercial and backyard flocks since February are indicated below:

This table confirms a declining incidence rate of cases among commercial flocks but unlike previous epornitics, outbreaks have persisted during late spring.

For 2025 to date, and based on an egg -producing population of 285 million hens, losses have attained:

Losses among caged hens are disproportionately high due to the effect of individual large complexes being affected.  Among the cage-free losses most were in large aviary complexes.  Organic and other cage-free hens in barns and in small commercial flocks were relatively unaffected despite regular feed delivery, egg collection and relatively lower levels of biosecurity as compared to in-line complexes.

Despite the USDA whack-a-mole approach to eradication and for the past three years as a program of control, highly pathogenic avian influenza has become endemic in the U.S. High risk areas include wetlands where migratory waterfowl congregate and along the four major flyways.  Although rapid flock depopulation has apparently reduced inter-flock transmission, it is obvious that virus is introduced into large complexes with power ventilation, whether caged or aviary housed, by the aerogenous route. Additional mechanisms include infected rodents, defects in biosecurity, transport and vaccination crews.

For the past three years, the industry has suffered from a lack of epidemiologic information relating to risk factors and specific routes of introduction of virus. It is known that APHIS in conjunction with federal and state wildlife agencies has conducted surveys on free-living mammals and birds in the vicinity of outbreaks on large complexes.  Results have yet to be published. These deficiencies have impeded the design and implementation of innovative methods of protection including vaccination.

Responding to high egg prices and escalating costs for control, the USDA announced a ‘five-pronged’ approach to address HPAI that effectively offered nothing new especially in the immediate and short-term. The program studiously avoided adoption of vaccination as an adjunct to biosecurity alone that clearly fails to offer absolute protection from infection.

On May 16^th, the Brazil, Ministry of Agriculture reported a confirmed outbreak of highly pathogenic avian influenza (HPAI) in a broiler breeder farm with 17,000 birds located in the Municipality of Montenegro in the state of Rio Grande do Sul.  The farm concerned  Is contracted to Vibera Foods that has an association with Tyson Foods. The farm was rapidly depopulated and eggs were retrieved from hatcheries in the state in addition to facilities in Minas Gerais and Parana states.

The outbreak occurred concurrently with a diagnosis in a bird sanctuary in Sapucaia do Sul, approximately 30 miles from the index case. It is presumed that this facility with a lake and the index farm were infected  concurerently by migratory birds rather than by direct or indirect contact. Brazil has reported numerous diagnoses of avian influenza H5N1 in migratory birds along the Atlantic littoral but prior to the present report the infection has not occurred in commercial flocks. 

Predictably the report resulted in importing nations imposing embargos that will impact exports over the short term but may have longer term implications for both Brazil and world broiler trade if additional cases emerge or are disclosed especially if in multiple states. At the outset, the U.S. broiler industry should refrain from Schadenfreude, that unique Teutonic characteristic of deriving pleasure in someone else’s misfortune.  Brazil expects to resume exports in the near future since many customer nations are imposing only limited localized embargos and will follow the World Organization of Animal Health (WOAH) limitation of 28 days following completion of decontamination. Despite an optimistic statement from the USA Poultry and Egg Export Council concerning acquisition of new markets, U.S. integrators are currently unable to supply the whole birds and other products exported by Brazil.

Investigations subsequent to the Rio Grande do Sul outbreak failed to confirm HPAI in commercial farms located in Ipumirim in Santa Catarina and in Aguiarnopolis in Tocantins state. In addition a number of backyard flocks have yielded negative results.

To place the importance of Brazil in perspective, production in Brazil during 2025 will attain 15,250 million metric tons representing 14.4 percent of world output of 105.8 million metric tons, excluding feet. Production in Brazil is approximately 70 percent of projected U.S. output of 21.7 million metric tons.

Domestic consumption in Brazil will attain10.17 million metric tons in 2025, equivalent to a per capita value of 47.9 kg. assuming a population of 212 million.  According to USDA estimates, Brazil will export 5.3 million metric tons comprising a diverse range of RTC products in 2025 representing 37 percent of world trade and 1.7 times the volume of U.S. exports of 3.3 million metric tons, with 97 percent as leg quarters.  In 2024 Brazil exported 5.3 million metric tons valued at $9.94 billion at a unit price of $1,878 per ton.  In comparison the U.S. exported 3.3 million metric tons valued at $4.8 billion equivalent to a unit price of $1,459 per metric ton, reflecting a preponderance of relatively low-value leg quarters.

Exports of poultry products from Brazil including fertile eggs, breeding stock and RTC could be severely impacted given initial nationwide embargos by China, the E.U. and South Korea. Some nations recognizing their respective needs for chicken from Brazil have imposed state or regional embargos including Japan, Saudi Arabia and the United Arab Emirates among 17 nations.

The potential for disruption in trade from Brazil can be judged by 2024 exports:

During the first quarter of 2023 neighbors of Brazil including Argentina, Bolivia, Uruguay, Peru and Ecuador reported HPAI, strain H5N1 in wild birds, backyard flocks and some commercial farms.  In addition, Peru reported the death of over 1,000 sea lions and more than 65,000 migratory marine birds.  At this time, Brazil announced that suspect cases of HPAI in Rio Grande do Sul and Amazonas states were negative for the pathogen.  Producers in Brazil implemented extreme biosecurity measures to prevent infection, given the probability of introduction of the disease into commercial flocks by migratory birds following the pattern in north and central America and also in Asia and Africa.  By May 15^th 2023, Brazil had diagnosed 139 cases of HPAI in wild birds and subsistence poultry but inexplicably not on commercial farms as defined by the World Organization of Animal Health.

Carlos Favaro, the Minister of Agriculture for Brazil announced an emergency program to combat HPAI in August 2023 as a result of the extensive infection among migratory birds.  This was in recognition that any outbreak of HPAI in a commercial flock would trigger national, regional or state bans on shipments by importers including China and middle-East nations.

Brazil has remained free of reported avian influenza until the recently disclosed outbreak.

In mid-July 2024, Brazil suspended exports of all poultry products following mortality on a single table-egg production farm that was eventually diagnosed as velogenic, viscerotropic Newcastle disease (END) acquired following contact with wild birds.  After prompt depopulation and appropriate quarantine measures with surveillance, exports resumed with corresponding assurances to importers.  At the time it was questioned whether the specific case was in fact END since response to this infection would have been the same as an isolated case of HPAI. 

Brazil has a history of withholding information on diseases which may impact exports.  This is exemplified by Tom Vilsack, then USDA Secretary of Agriculture, addressing a formal letter to the Government of Brazil requiring improvement in detection and reporting of bovine spongiform encephalopathy. He stated “I urge Brazil in the strongest terms to continue its progress in streamlining timely animal disease reporting.”  The admonition by the USDA followed delays in reporting BSE with two cases of atypical infection diagnosed without prompt notification to the WOAH or importers.  Punitive import restrictions were imposed by trading partners on beef from Brazil following the revelation leading to the rejection of 140,000 metric tons of beef valued at $20 billion.  The fact that Brazil repeatedly failed to report cases of BSE raises the question of HPAI in commercial flocks.  The seven nations surrounding Brazil have reported H5N1 infection in free-living birds, backyard flocks or commercial farms but Brazil has only acknowledged extensive infection in migratory birds.

Conclusions can be derived from the most recent report of HPAI in a commercial flock in Brazil with implications for world trade:-

• HPAI is a panornitic occurring on all inhabited continents and including the Antarctic, affecting marine mammals and birds.  Accordingly, the question of “freedom” from highly pathogenic avian influenza and self-serving attempts to discriminate against exporters reporting localized or regional outbreaks is considered as factious.

• Avian influenza strain H5N1, clade 2.3.4.4b is endemic among migratory marine birds some species of which die of infection and others remain clinically unaffected carriers and disseminators of the pathogen.  Interaction among migratory marine birds and waterfowl through cohabitation on waterways and along coastal areas creates the risk of infection for susceptible commercial flocks.  Given that the pathogen can be transmitted by the aerogenous route over distances that may exceed one mile, even the most stringent biosecurity measures cannot assure absolute protection.

• The patchwork arrangement of trade agreements specifying embargos on entire nations, states or provinces or even regions are generally unjustified especially when importing nations report cases of HPAI in wild birds and free-living mammals and in their own commercial flocks.

• It is possible with PCR technology to confirm whether flocks of origin for exports are free of infection at the time of harvest allowing for certification under WOAH guidelines. 

• Given the geographic extent of both Brazil and the U.S. as the major exporting nations, imposition of countrywide bans is based either on ignorance of the epidemiology of HPAI or the misapplication of phytosanitary regulations to protect local industries.

• Despite the regularly updated recommendation of WOAH, there is an evident lack of uniformity in both adoption and recognition of diagnostic standards, certification and export regulations.  A point in question is compliance with the 28-day period following flock depopulation and decontamination following an outbreak of HPAI or END.  Some nations impose a 60-day embargo and in the case of China resumption of trade may be delayed for years. Harmonization and compliance with scientific standards is overdue.

• The overwhelming lesson from the ongoing panornitic, in progress since 2022, is that current methods of prevention are inadequate given the epidemiology of the infection.  Accordingly, the WOAH acceptance of preventive vaccination should be more extensively applied as an adjunct to biosecurity. Administration of commercially available effective vaccines should establish immune populations and would reduce inter-farm spread within a given area and will absolutely reduce expenditure on depopulation with accompanying indemnity.

Avian influenza should be regarded as the Newcastle disease of the 2020s.  During the 1970s END was in every way as catastrophic as HPAI and the infection is effectively suppressed in nations where a high level of immunity is achieved through diligent vaccination.