Performing Department
(N/A)
Non Technical Summary
Poultry feed requires sources of protein, energy, vitamins, and minerals. In conventional chicken diets in the United States, corn serves as the main energy source and soybean meal as the main protein source. A typical corn-soy-based diet meets the needs of most poultry with limited need for supplementation with synthetic amino acids because soybean meal has a high protein content and an excellent amino acid profile that compliments that of corn. While soybean meal is the dominant protein source in poultry diets, producers and consumers have expressed concerns that most soybeans are produced from genetically modified strains and soybeans contain phytoestrogens which may impact human health. Consequently, there is growing interest in soy-free diet formulations for poultry. Unfortunately, while many alternative protein sources have been studied in poultry, most of these ingredients can only be used for a small portion of the diet before causing detrimental effects. For example, research suggests that broilers fed diets containing as much as 20% field peas had similar growth performance as broilers fed a corn-soy control (Farrell et al, 1999). Dr. Fisher's own previous work suggested that that field peas can be used to replace about 30% of corn and soybean meal without sacrificing growth performance (Fisher, 2016). However, replacement of a larger portion of the soybean meal with field peas can result in reduced performance of growing chickens and laying hens (Farrell et al, 1999; Tuunainen et al, 2016). A potential alternative protein source that needs further research is hemp and hemp byproducts. Hemp (cannabis sativa) could be a better protein source than current soy alternatives (e.g., peas) because it has a higher protein content and is rich in sulfur amino acids. Hemp is currently cultivated for fiber and seeds, but hemp and its byproducts are not approved as animal feed ingredients in the United States. In a 2022 statement, the Association of American Feed Control Officials (AAFCO) specifically mentioned that additional research is needed to show that hemp is safe for animals to consume and that the resulting animal products are safe for humans to consume. The goal of this project is to evaluate the impact of replacing soybean meal with hempseed cake, a byproduct of hemp oil production, on the growth performance and production of different classes of growing poultry: fast-growing broilers, slow-growing broilers, and egg-type pullets. This evaluation will be conducted through a series of feeding trials using hempseed cake to partially or fully replace soybean meal in the diet. During each trial, the growth, feed consumption, feed efficiency, and carcass yields will be evaluated. Additionally, cannabinoid content of meat produced during the trials will be analyzed to address concerns that cannabinoids may be transferred to animal products when animals consume hemp or hemp byproducts. This project should produce valuable information about the effect of hempseed cake on the growth performance of chickens and the quality of their meat. These results will add to the body of literature needed to get AAFCO approval for hempseed cake as a feed ingredient for poultry. Approval would benefit poultry producers, expand markets for the hemp industry, and increase the sustainable use of natural resources which advances the USDA-NIFA strategic goal of managing climate resistance through adaptation and mitigation.
Animal Health Component
25%
Research Effort Categories
Basic
75%
Applied
25%
Developmental
(N/A)
Goals / Objectives
The primary goal of the proposed research project is to evaluate the potential of hempseed cake to replace soybean meal as a protein source for three different classes of poultry: fast-growing broilers, slow-growing broilers, and egg-type pullets. An additional goal is to train graduate and undergraduate students at Lincoln University in poultry nutrition research, and to increase stakeholder understanding of novel feed ingredient evaluation and the approval process for new feed ingredients.Research Objectives:Objective 1. Evaluate the effect of replacing soybean meal with hempseed cake on growth performance and carcass traits of fast-growing broilersObjective 2. Evaluate effect of replacing soybean meal with hempseed cake on growth performance and carcass traits of slow-growing broilersObjective 3. Evaluate effect of replacing soybean meal with hempseed cake on growth performance of egg-type pulletsObjective 4. Evaluate cannabinoid content of meat produced by chickens fed hempseed cake
Project Methods
A series of caged feeding trials will be conducted to evaluate the use of hempseed cake, an industrial hemp byproduct, to replace soybean meal in the diets of growing chickens. Separate feeding trials will be conducted for fast-growing broilers, slow-growing broilers, and egg-type pullets. During each feeding trial, chickens will be housed in wire cages (61cm wide x 61cm deep x 45.7cm high) which contain individual feeders, individual nipple drinkers, and manure catch trays. Trials will include a control diet and two experimental diets. Experimental diets will either partially or fully replace soybean meal with hempseed cake. For all experiments, the control and experimental diets will be sent to an independent laboratory for proximate analysis and to test for cannabinoids, heavy metals, and mycotoxins. Because hemp and hemp byproducts are not currently approved animal feed ingredients, all unconsumed feed, carcasses, and meat produced by experimental birds will be incinerated at the end of the trial.Objective 1: Evaluate the effect of replacing soybean meal with hempseed cake on growth performance and carcass traits of fast-growing broilersFast-growing broiler strains (e.g., Ross 308) were developed for the large-scale commercial poultry industry. However, they are also commonly used by small-scale producers because they are readily available, grow quickly, and have excellent feed conversion. These birds are usually processed between 6 and 8 weeks of age when they reach a live weight of 6 lbs.Task 1.1: Fast-growing broiler feeding trialApproximately 60 1-day-old chicks from a commercial fast-growing boiler strain will be purchased for this experiment. Upon arrival, chicks will be weighed and equally divided into groups of 5. Each group will be placed into one of twelve wire cages providing an initial stocking density of 0.07 square meters per bird. Cages will be randomly assigned to one of three treatments (control, diet 1, or diet 2) in a completely randomized block design providing four replications for each treatment. The control diet will be based on a conventional corn-soy formulation. Experimental diets will be formulated to partially or fully replace soybean meal with hempseed cake. Diets will be formulated to meet the nutritional requirements recommended by the breed and be isonitrogenous with a target of 20% crude protein. A sample of each diet will be sent to an outside laboratory for a proximate analysis and a hemp potency screening. The hemp potency screening will test for the presence of THC, CBD, and other cannabinoids as well as heavy metals and mycotoxins.Feed and water will be provided on an ad libitum basis. Throughout the trial, environmental conditions will be managed according to breeder recommendations. All trial birds will be weighed weekly and feed intake will be monitored to determine total feed intake and feed conversion ratios. Mortality will be recorded daily. Growth performance will be monitored through processing at about 7 weeks of age.Task 1.2: Fast-growing broiler carcass evaluationAll experimental birds will be processed on farm at about 7 weeks of age. Data collection at processing will include live weight, carcass weight, WOG (weight without giblet) yield, and part yields from all birds. Additionally, samples of breast meat, thigh meat, and liver from one bird in each pen will be collected to test for the presence of THC, CBD, and other cannabinoids.Objective 2: Evaluate effect of replacing soybean meal with hempseed cake on growth performance and carcass traits of slow-growing broilersSlow-growing broiler strains (e.g., Freedom Ranger, Red Ranger) are hybrids that were developed in response to concerns about the fast growth rate and health issues of fast-growing broilers. Slow-growing broilers are commonly used by small-scale poultry producers because they are more active and better foragers than fast-growing broilers. Slow-growing broilers are typically processed at 9 to 11 weeks of age when they weigh about 5 to 6 pounds.Task 2.1: Feeding trial with slow-growing broilersApproximately 60 1-day-old chicks from a commercially available slow-growing broiler strain will be purchased for this experiment. The experimental design will be identical to the design of the fast-growing broiler feeding trial proposed in objective #1, except slow-growing broilers will be processed at 10 weeks of age.Task 2.2: Slow-growing broiler carcass evaluationData collection and procedures for this trial will be identical to those proposed for objective #1 apart from the experimental timeline. All experimental birds will be processed on farm at about 10 weeks of age. At processing, data collection will include live weight, carcass weight, WOG (weight without giblet) yield, and part yields from all birds. Samples of breast meat, thigh meat, and liver from one bird in each pen will be collected to test for the presence of THC, CBD, and other cannabinoids.Objective 3: Evaluate effect of replacing soybean meal with hempseed cake on growth performance of egg-type pulletsEgg-type pullets (e.g., ISA Brown, Novogen Brown) are hybrid varieties that have been selectively bred and crossed to efficiently produce eggs. These breeds are popular among small poultry producers because chicks can be sexed at hatch and the hens produce large eggs.Task 3.1: Feeding trial with egg-type pulletsApproximately 60 1-day-old egg-type pullets will be purchased for this experiment. When chicks arrive, they will be weighed and equally divided among twelve wire cages. Each cage will contain 5 pullets with a stocking density of 0.07 square meters per birds. Each of three treatments (control, diet 1, and diet 2) will be randomly assigned to four replicate cages in a completely randomized block design. The control diet will be based on a conventional corn-soy formulation. Experimental diets will be formulated to partially or fully replace soybean meal with hempseed cake. Diets will be formulated to meet the nutritional requirements recommended by the breed and be isonitrogenous with a target of 19% crude protein. A sample of each diet will be sent to an outside laboratory for a proximate analysis and a hemp potency screening. The hemp potency screening will test for the presence of THC, CBD, and other cannabinoids as well as heavy metals and mycotoxins.Feed and water will be provided on an ad libitum basis. Throughout the trial, environmental conditions will be managed according to breeder recommendations. All trial birds will be weighed weekly and feed intake will be monitored to determine total feed intake and feed conversion ratios. Mortality will be recorded daily. Growth performance will be monitored through approximately 20 weeks of age.Task 3.2: Egg-type pullet carcass evaluationWhile egg-type pullets are not typically raised for meat production, there is a need to determine whether THC, CBD, and other cannabinoids are transferred to the meat or eggs of animals fed hemp or hemp byproducts. To this end, one pullet per pen will be humanely euthanized at approximately 20 weeks of age. Samples of breast meat, thigh meat, and liver will be collected to test for the presence of THC, CBD, and other cannabinoids.Objective 4: Evaluate cannabinoid content of meat and eggs from chickens fed hempseed cakeTo determine whether cannabinoids are transferred into the meat of growing chickens fed hempseed cake, feed samples will be tested for Δ9-THC, CBD, and several other cannabinoids by the LU Hemp Institute and an independent certified laboratory. Assuming that cannabinoids are present in the feed, animal products produced by the experimental birds will be shipped to an independent laboratory for cannabinoid potency testing. These samples will include breast meat, thigh meat, and liver tissue from one bird per pen at the conclusion of each feeding trial.