EVERY year, the U.S. poultry industry incubates about 9 billion eggs to hatch the chicks that will eventually become billions of pounds of meat, most of which will be consumed domestically, according to Dr. Craig Coufal, a Texas A&M AgriLife Extension Service poultry specialist in College Station, Texas.
Eggs destined to hatch into broiler chicks are not normally washed, Coufal said. Instead, producers have accepted 1% or more losses from bacteria entering the shell and causing the egg to become rotten, the embryo to abort or the chick to hatch malformed.
A 1% loss may not seem like much, Coufal noted, but 1% of 9 billion means a loss of about 90 million chicks yearly.
"It's a highly competitive industry that measures profit per chick as a penny or two," he said. "If we could just cut that 1% loss in half, it would represent substantial savings to the industry."
When an egg is laid, it is coated with a waxy layer called the "cuticle," which seals the pores of the eggshell for the first week or so, working as a kind of "invisible natural barrier" against bacterial invasion, Coufal explained.
The cuticle protects the egg until the embryo needs to respire — to take in oxygen and give off carbon dioxide. During the early stages of development, the embryo doesn't need much oxygen, but as its needs increase, the cuticle breaks down and flakes off, allowing the pores to open up and the embryo to breathe.
For eggs to be safely eaten, producers use mild detergents along with water as hot as 110-120 degrees F to sanitize them, according to Coufal. Although such washing sanitizes the eggs for consumption and does not change the taste or nutritional content of eggs, it also destroys the delicate cuticle.
"The breeder part of the poultry industry does not want hatchery eggs to even get wet as it is believed that may aid bacteria to enter the pores and may actually increase the number of rotten eggs during incubation," Coufal said.
To this end, Coufal and his team have designed a machine that can sanitize eggs quickly and cheaply without leaving a residue that could damage the cuticle or interfere with the embryo's natural development.
Coufal hopes his egg sanitizing machine revolutionizes the poultry industry.
Coufal actually started the project for his master's thesis in 1999. Since then, he has done lab tests on egg sanitization, mainly by hand in the lab, but wanted to streamline the process so it could be used commercially.
He and his colleagues started construction on a prototype in early 2012.
"We built it with common shop tools using off-the-shelf materials," he said.
The machine sprays the eggs with hydrogen peroxide, followed by exposure to germicidal ultraviolet light, which is similar to the process used to sterilize barbershop equipment or medical instruments.
During 2012, they did a lot of fine-tuning and found that they needed two treatments of hydrogen peroxide, each followed by a bath of ultraviolet light, to achieve the high sanitization rate.
Coufal found that neither the hydrogen peroxide nor the ultraviolet light treatment alone was sufficient to completely kill bacteria on the egg's surface; however, when the treatments are used together, his lab tests found that eggs are rendered essentially bacteria free. This is because the ultraviolet light changes the hydrogen peroxide into hydroxide ions, which actually conduct the sanitization process.
"With most eggs treated with the process, we are unable to culture any bacteria at all," he said.
The process proceeds very quickly within a protective housing, allowing the eggs to be carried on a rapidly moving conveyor belt, he said. The hydroxide ions quickly react with the bacteria or other matter and are consumed, leaving no toxic chemicals to be disposed of or any residue on the egg.
Just as important, there's no apparent damage to the egg cuticle.
"We haven't found any increase in bacteria invasion into the egg or any loss of hatching weight that would signal that we've damaged the cuticle," Coufal said.
Earlier this year, a local machine fabricator finished building a second-generation unit based on Coufal's prototype. The second-generation unit has electronic controls and monitoring and automatic shutdowns.
During the next year, Coufal, working with a local commercial hatchery, will measure just how effective the sanitization process is in reducing egg losses during large-scale field testing.
A remarkable, long-term trend in animal nutrition research was on display at the recent Poultry Science Assn. (PSA) annual meeting in San Diego (as well as the joint annual meeting of the American Dairy Science Assn. and American Society of Animal Science in Indianapolis, Ind., where a surprising amount of poultry research was presented).
Nutrition researchers have long studied alternatives and novel ingredients so that as traditional corn/soybean meal diets increase in cost and/or decrease in availability, livestock and poultry producers would have ample scientific data on potential alternatives before a crisis point is reached.
For example, at PSA, J.W. Boney, A.E. Lamp and J.S. Moritz of West Virginia University presented abstract 43 on how wheat supplementation of corn/soybean meal-based diets affects the manufacture of pellets and subsequent performance of turkeys consuming the diet.
They noted that current corn prices and the benefits associated with pelleting rations may encourage wheat supplementation in turkey diets. The objectives of this study were to describe the manufacturing effects of corn/soybean meal-based diets with and without supplemental wheat and to assess turkey performance when these diets were fed.
Boney et al. said the wheat source was a hard winter variety with an analyzed crude protein level of 10% and a calculated neutral detergent fiber and acid detergent fiber content of 9% and 3%, respectively. Wheat was included at 15% of the formulation using calculated nutrient values to meet poult requirements.
Dietary nutrient values were calculated to be similar between the wheat-supplemented diet and corn/soybean meal diet, the researchers reported. Pellets were conditioned at 79 degrees C for 10 seconds, extruded through a 4.7 mm x 38 mm die and crumbled before poult feeding. A coated phytase was added at the mixer, and a multi-enzyme preparation was added post-pelleting for both diets.
Eight replicate pens of 80 male Hybrid Converter poults were fed either the wheat-supplemented diet or the corn/soybean meal-based diet for six weeks.
According to Boney et al., the wheat-supplemented diet increased pellet mill motor amperage by 5%, hot pellet temperature by 0.6 degrees C and production rate by 2% relative to the corn/soybean meal-based diet. Wheat inclusion increased pellet durability by 4% and improved the percent crumbles retained on a No. 6 Tyler sieve (3.35 mm) by 20%.
The average particle size of crumbles from the wheat-supplemented diet was 18% greater than from the corn/soybean meal-based diet, they noted.
Poult feed intake, weight gain, feed conversion ratio and mortality percentage were not affected by dietary treatment (P < 0.05), Boney et al. added.
Canola meals. Over time, canola breeders have developed additional varieties of canola seed with different attributes than the conventional canola on which most nutritional studies have been based.
Therefore, C. Parr, X. Chen and C. Parsons of the University of Illinois evaluated canola meals from nine new canola seed varieties and compared them to conventional canola meal (abstract 45).
Parr et al. said initial results showed that the test canola meals had higher levels of crude protein and amino acids than the conventional meal. All of the test meals also had lower fiber values, as measured by acid detergent fiber and neutral detergent fiber, the researchers snoted.
Parr et al. conducted precision-fed rooster assays to determine the true metabolizable energy (TMEn) of the test canola meals wherein roosters were tube-fed 30 g of canola meal and excreta were collected for 48 hours post-feeding.
According to Parr et al., when TMEn values of the canola meals were compared, all of the test meals had higher values than the conventional canola meal (P < 0.05).
Precision-fed cecectomized rooster assays were also conducted to determine standardized amino acid digestibility in the canola meals. Standardized amino acid digestibility values for most of the test meals were higher than those for the conventional meal (P < 0.05), Parr et al. explained, and the test canola meals contained much higher levels of digestible amino acids than the conventional meal due to their higher protein and amino acid content.
The results of this study indicate that canola meals from the new varieties of canola seeds have increased TMEn and digestible amino acid levels for poultry compared with conventional canola meal, the researchers concluded.
Parr et al. did not indicate in the research abstract the particular new varieties that were tested.
Sweet potato root meal (SPRM). Researchers at Tuskegee University in Alabama presented several abstracts and posters at PSA on evaluating SPRM as a feed ingredient for broilers.
In abstract 226, R.C. Beckford, J.R. Bartlett, E.G. Rhoden, V.A. Khan, M.A. McHugh and K.M. Liles of Tuskegee said after a complete nutrient analysis of SPRM, four treatment diets were formulated in which 0%, 10%, 20% and 30% of corn was substituted with SPRM.
The study utilized 360 one-day-old Cornish Rock male broilers that were randomly assigned to one of the four treatments. Bodyweight and feed intake were monitored weekly for seven weeks.
Birds were slaughtered on day 50, and feed intake, bodyweight gain, average daily gain (ADG), average daily intake, abdominal fat, dressing percentage and internal organ weights were measured. White/breast and dark/leg-and-thigh meat were evaluated for nutrient content (protein, moisture, fat and ash), Beckford et al. said.
According to the researchers, the results showed no significant differences among treatments for feed intake, ADG and feed efficiency. Birds fed 30% SPRM had a higher (P < 0.05) bodyweight gain of 2,938.60 g and ADG of 59.97 g per day than birds fed 20% SPRM, which had 2,617.14 g of bodyweight gain and 53.39 g per day of ADG. There were no differences in dressing percentage among treatments.
Abdominal fat was highest (P < 0.05) in birds fed 30% SPRM, Beckford et al. reported, noting that organ weights were similar across treatments.
Moisture, protein and ash contents of white meat were not different among treatments. However, fat content was lower (P < 0.05) in birds fed no SPRM (2.16%), Beckford et al. said. For dark meat, protein and ash contents were similar among treatments, while moisture and fat contents were different (P < 0.05).
Birds fed the SPRM diets compared well with those fed the control for both performance and nutrient content of meat, the researchers concluded.
Dietary fat types. Tuskegee researchers K.M. Liles, J.R. Bartlett, R.C. Beckford, K. Washington, E.G. Rhoden and V.A. Khan presented poster P413 on the performance and meat quality of broilers fed different types of dietary fat.
Fat is an important ingredient in poultry diets. The use of oils and fats in broiler diets may influence the performance as well as the composition and quality of the carcass, Liles said.
In birds, body fat composition is similar to the dietary fat source because dietary fats are generally not altered during digestion and absorption, the researchers explained. Therefore, this study was conducted to evaluate bodyweight gain, feed intake, feed efficiency, ADG, average daily feed intake, dressing percentage, non-carcass components (internal organs, feet and neck) and meat quality (protein, fat, moisture, ash and color) of broilers fed different types of fat.
Liles et al. said this study utilized 180 one-day-old Cornish Rock male broiler chicks that were wing-banded, weighed and randomly assigned to one of four dietary treatments that included poultry fat, peanut oil, vegetable oil or canola oil.
Each treatment consisted of 45 birds with three replications of 15 birds. Bodyweights and feed intake were recorded weekly. After 49 days, birds were slaughtered, and non-carcass components were harvested and weighed. Samples from each treatment were analyzed for color, moisture, fat, ash and protein.
Results showed no significant differences among treatments for total feed intake, average daily feed intake, total bodyweight gain, ADG and feed efficiency, Liles et al. reported (data not presented). Dressing percentage and non-carcass components were not significantly different among treatments. No significant differences were found among treatments for protein, ash, fat and moisture.
Color was not significantly different for L* (lightness) and a* (redness) values among treatments, Liles et al. added; however, the poultry fat treatment was different (P < 0.05) from the canola oil treatment for b* (yellowness) values, with readings of 11.28 and 4.92, respectively. This indicated that broilers fed poultry fat developed more yellow pigmentation compared with those fed canola oil, Liles et al. said.
Based on the parameters evaluated in this study, the researchers concluded that the four fat sources had similar effects on the performance of broiler chickens.
Algal residue. J. Price, T.A. Wickersham, M.P. Williams, J. Klein and J.T. Lee of Texas A&M Agrilife Research presented the results of two experiments that evaluated a post-extraction algal residue (PEAR) as a feed ingredient for broilers and laying hens (poster P416).
Price et al. said PEAR was determined to contain 20.2% crude protein, 6.18% calcium, 6.61% sodium and 1.56% fat, and a complete amino acid, vitamin and mineral analysis was conducted before diet formulation.
In experiment 1, five increasing concentrations (0%, 5%, 10%, 15% and 20%) of PEAR were included in 31-week-old White Leghorn laying hen diets, Price et al. said. Hens were fed the diets for a period of five weeks. During the experiment, parameters evaluated included weekly feed consumption, egg production, egg weight and interior egg quality.
Increasing PEAR concentrations had no effect on egg production or feed consumption throughout the experiment. However, yolk color was increased (P < 0.05) in the 10% PEAR diet following two weeks of consumption, Price et al. reported.
In experiment 2, five increasing concentrations (0%, 2.5%, 5.0%, 7.5% and 10.0%) of PEAR were fed to broilers through three weeks of age to determine the effect on feed consumption, bodyweight and feed conversion ratio. Additionally, fecal moisture percentage was evaluated at 20 days of age due to the high sodium content of PEAR, the researchers said.
Price et al. noted that PEAR inclusion did not negatively affect feed consumption, bodyweight or feed conversion ratio throughout the three-week experiment, but an increase (P < 0.05) in fecal moisture was observed in the 7.5% and 10.0% dietary treatments.
These data indicate that PEAR can be included in poultry diets without negatively affecting performance and supports further investigation in longer laying hen and broiler experiments, Price et al. concluded.