July 13, 2012

 

US poultry industry hurt by hot weather

 

 

US' Delmarva's 1,700 poultry farms are being challenged by the recent hot weather, especially those with a flock close to harvest-size.

 

"This is going to be my last summer flock," said Perdue Farms grower Jack Lavelle, 68, of Accomac, adding, "Literally, around seven in the evening, you can feel the heat coming off them."

 

Lavelle, who has been in the business since 1970, said summers are getting hotter, meaning there is greater stress on flocks. Moreover, he said he will spend in excess of US$3,000 this month on electricity to run three broiler houses with a capacity of 50,000 birds.

 

The flock Lavelle has now is five weeks old -- the size where high temperatures become especially dangerous. The chickens go to market at between 49 and 51 days old.

 

"The closer you are to market weight, the more difficult it is," said Nathaniel Tablante, extension poultry veterinarian with the Virginia-Maryland Regional College of Veterinary Medicine at the University of Maryland, College Park.

 

"At 100-plus degrees like we are having right now, it's very difficult to manage," he said.

 

Because chickens do not perspire like humans, the only way they can cool off is by panting, he said.

 

The normal body temperature of chickens is higher than humans' body temperature -- between 104 and 107 degrees Fahrenheit.

 

"You factor in the high heat and they'll start panting," Tablante said. When chickens approach market size, all that panting expels a lot of heat and moisture.

 

"They can drown in their own moisture," he said.

 

A flock of 25,000 four-pound birds can give off one million British Thermal Units per hour of heat. About 11 million chickens per week are produced on Delmarva, according to Delmarva Poultry Industry, a trade association.

 

Sussex County ranks first among America's counties in broiler production. Among the Maryland counties, Somerset County ranks 25th, Worcester ranks 26th and Wicomico ranks 36th in the nation.

 

Accomack County ranks 72nd and produces about 10% of Virginia's broilers.

 

The wholesale value of broilers, roasters and Cornish hens produced on the Peninsula last year topped US$2.2 billion, according to DPI.

 

University of Maryland Extension Poultry Specialist Jennifer Timmons said equipment failure is the greatest challenge growers' face in the summer, especially those with older houses.

 

Farmers must be constantly vigilant when temperatures go up, as they have this week, Timmons said.

 

"If they've got big birds right now, they're not leaving the farm," she said.

 

Delmarva farmers grow chickens for one of four companies, which have technical staff on board to advise them how to deal with weather extremes.

 

Fewer chickens are placed in each house in the summer, for example, Tablante said.

 

"They measure it in terms of square footage per bird," she said.

 

Companies may also advise farmers to add electrolytes to drinking water and, most importantly, to ensure fans and other equipment are functioning properly.

 

Lavelle was out until eight in the evening. Making plumbing repairs to ensure his flock's safety with two more days of dangerous temperatures anticipated. Although temperatures like those in the region this week can tax even the best-designed systems, modern chicken houses are designed to keep chickens cooler during extreme conditions.

 

"Today's poultry houses are environmentally controlled, protecting the chickens from the extreme temperatures that have caused extensive heat losses in the past," said Perdue Farms spokeswoman Julie DeYoung.

 

As result, Perdue's growers have had "very few losses due to the heat, less than 9,000 of the 30 million chickens that are on Delmarva farms at any given time," she said.

 

Among the most important innovations is tunnel ventilation, replacing the older method of growing chickens in open-sided houses. Like a wind tunnel, large exhaust fans at each end of airtight houses draw air through and over evaporative cooling pads, causing cool air to pass over the chickens. The effect is like air conditioning -- even on hot days, temperatures should remain in the 80s inside, Tablante said.

 

Fans, lighting and feed all are controlled by computers nowadays. Controlling the light level and providing feed during the coolest part of the day help chickens be less stressed in hot weather.