Recipient Organization
VIRGINIA POLYTECHNIC INSTITUTE
(N/A)
BLACKSBURG,VA 24061
Performing Department
Animal Poultry Sciences
Non Technical Summary
Problem Statement. In current intensive livestock production, including poultry production, animal welfare can be at risk. Consumers have shown increased interest and concern for animal welfare of livestock (Zimbelman et al., 1995; Harper and Henson, 2001; Eurobarometer, 2005; ASPCA, 2016), resulting in market segregation and arising animal welfare assurance schemes with product labeling (for example organic and cage-free). Mainly animal rights activists, who highlight abuse, make the consumer aware of production issues. These animal rights campaigns could have a devastating effect on the image of the livestock and poultry industries (Hughes, 1995; Tonsor and Olynk, 2011). Relevance to advancing Virginia/Region and the US. Broiler chicken production is the number one agricultural commodity in Virginia, with a monetary value of ~733 million dollars (VDACS, 2016). Both poultry production and processing have a large impact on the state - direct as well as indirect economic influence. US poultry meat production is nearly 9 billion birds annually. The US houses circa 300 million laying hens. Potential economic losses per bird could have a huge impact for both the state of Virginia and the US.The poultry industry is making efforts to improve animal welfare standards, usually by setting standards that avoid animal suffering. Yet, the avoidance of suffering does not necessarily result in good welfare; more likely animals will experience a neutral state of well-being. Therefore, consumers and producers both benefit from practical, commercial methods to provide positive welfare states among livestock, including poultry. The aim is to avoid poor welfare and move towards positive welfare by providing appropriate, species-specific enrichments. The specific aim of project 1 is to test the impact of two types of environmental enrichment on behavior and productivity, focusing on pedigree stock.Besides animal welfare concerns, sustainability receives more attention from consumers, producers and (non-) governmental organizations (Ransom, 2007; Kjaernes et al., 2008). Sustainability includes animal-friendly production with few or no losses (mortality), and is especially relevant for current producers and future generations. Animal mortality is an economic loss, since feed, water and energy (input) are wasted and production values or slaughter yield (output) is reduced. Therefore, research should focus on ways to improve welfare and reduce mortality during production. The specific aim of project 2 is to assess the impact of sanitation water treatments on broilers in a challenging environment with potential pathogens present. We will assess three water sanitation treatments (compared to control) on production, welfare, and drinking behavior. Additionally, the specific aim of project 3 is to identify the impact of northern fowl mites on nocturnal laying hen behavior.Animal welfare is an important aspect of intensive animal production, and should be taken into account by all people involved during each production phase, including when birds are killed. On-farm euthanasia of large heavy poultry, including broiler chickens, can be particularly challenging, and the operator's ability to kill humanely depends greatly on their physical strength. The strength required to hold a mature broiler and then pulling down its head to cause cervical dislocation may be physically impossible for most people, thus often other methods are used. Killing can induce additional pain and distress for the animal if not performed properly and quickly. Therefore, the industry needs practical and safe methods to achieve rapid loss of consciousness and death for these large animals. The specific aim of project 4 is to evaluate two euthanasia methods utilized for broilers.Approach. We will study multiple stages of the poultry production chain, with a common focus on commercially applicable welfare improvements. Poultry types included will be breeder flocks, meat-type birds and layer-type birds. Included phases are the rearing phase, production phase, and euthanasia. Research will focus on experimental testing of potential welfare improvements.Anticipated Outcomes and Impacts. Improved animal welfare can be directly beneficial for the consumers (end-users) and the industry, the latter in the form of increased work satisfaction, work safety, income, and positive public perception. Governmental organizations and animal welfare organizations can benefit from the science-based knowledge on animal welfare improvements, which could be included in legislation, guidelines and animal welfare assurance schemes. Outcomes will include advice on practical environmental enrichments for commercial use, fact sheets for the industry on standards for improved welfare, presentations and posters on scientific and industry-focused meetings, and guidelines to improve human-animal interactions.The ultimate goal of this study is to raise (conventional) poultry production to a higher level of animal welfare.
Animal Health Component
100%
Research Effort Categories
Basic
0%
Applied
100%
Developmental
0%
Goals / Objectives
The overarching goal of this study is to raise (conventional) poultry production to a higher level of animal welfare. I will approach this goal by pursuing several objectives that address the emphasis on the animal, the process, the environment, and the workforce. Four projects are outlined to meet these objectives.Objective project 1: The aim of the current study is to test the impact of two types of environmental enrichment on single-housed roosters on behavior and productivity. This study is particularly important for poultry kept for research purposes and for commercial poultry kept as pedigree stock.Objective project 2: The aim is to study the impact of sanitation water treatments during grow-out on broiler production values, intestinal lesions, footpad dermatitis, hock burns and chronic stress. We aim to study the impact of water treatment A compared to B, C or no treatment (control) on production (average daily gain, body weight, feed conversion, mortality), long-term stress response, footpad dermatitis lesions and hock burns.Objective project 3: Identify the impact of northern fowl mites on nocturnal laying hen behavior. Although the experiment has already been executed at UC Davis, the behavioral data still needs to be collected, analyzed, written and published.Objective project 4: The objectives are to comparatively evaluate two euthanasia methods utilized for broiler chickens. Following euthanasia method development and verification, extension materials and programming will be developed for distribution to the poultry production and research industry.
Project Methods
Methods and Procedures Project 1All experimental procedures are approved by the Virginia Tech Institutional Animal Care and Use Committee (IACUC; protocol number 17-198). For this study, four White Leghorn lines kept for reproductive purposes (n = 36 healthy birds) will be studied. The lines are selected for low antibody numbers (Low Select and Low Relaxed) or high antibody numbers (High Select and High Relaxed) and are kept as a pedigree flock at Virginia Tech. Birds are housed in individual barren cages that are equipped with a nipple drinker and feed trough. Results of this study are specifically relevant for chickens, and perhaps even only males. The sample size is based on the available number of birds. These birds are kept as pedigree flock.Experimental design: We will provide birds with continuous access to one or two enrichments. Treatments will be equally divided over the four genetic lines, resulting in 3 treatment groups * 12 birds per treatment group. The first enrichment is a bunch of strings (white polypropylene baling twine) suspended from the top of the cage, not touching the bottom of the cage. The second enrichment is a string with ping-pong balls that will be placed in the feed trough. Birds will serve as their own control (no enrichment). At 36 weeks of age, we will collect baseline data (home-cage behavior, fearfulness, body weight, semen volume). Thereafter birds will receive the enrichment for 3 days.Measurements: Behavioral observations, semen volume, beak length, body weight, and fearfulness. Data will be analyzed with mixed models and post-hoc adjustments in SAS.We hypothesize that roosters who received the enrichment condition will have greater semen volume than the no-enrichment control. We hypothesize that chickens who received the enrichments are less fearful, show less stereotypies and more forage-related behaviors than without enrichment. We hypothesize that birds with two enrichment will show more enrichment-directed behaviors (e.g. pecking at enrichment, manipulating enrichment with beak or feet) than birds with one enrichment type.Methods and Procedures Project 2This study will include a single trial with four water sanitation treatments (A, B, C, no (control); Table 1) and two housing treatments (contaminated litter versus clean litter (control)). Water lines will be disinfected before the start of the experiment. All aspects of this project were approved by the IACUC (protocol 17-232).Experimental setup: Seven hundred-and-twenty seeder birds (Cobb) will be placed on clean litter with clostridium spores present until 21 days of age. The birds will be challenged with a coccidiosis vaccine, resulting in reduced production, increased mortality, and pathogen shedding. Experimental birds (Ross 708 * Hubbard) will be either housed on clean litter or built-up litter from the seeder flock with clostridium spores and coccidian protozoa present. The experimental birds will receive one of four water treatments: fully activated chlorine dioxide, partially activated chlorine dioxide, iodine-based treatment, tap water (control group). The experiment will end at day 35. The experiment includes a 4*2 factorial setup with 4 water treatments and 2 litter treatments. Each will have nine repetitions (pens) with 27 birds.Measurements: Clostridium perfringens infection, production (mortality, body weight, feed intake, feed conversion, average daily gain per bird per day), footpad dermatitis, hock burns, long-term stress (adrenal gland weight and asymmetry), water consumption, and litter moisture. Data will be analyzed with mixed models and post-hoc adjustments in SAS.Methods and Procedures Project 3All aspects of this project were approved by the Institutional Animal Care and Use Committee (IACUC), University of California, Davis. Sixteen Hyline W-36 White Leghorn laying hens (Gallus gallus) were used from 25 weeks of age. The hens were beak trimmed at the commercial hatchery to mimic commercial management. The hens were housed individually in wire cages, with a dust box. The banks of cages had automatic water cups and a feed trough with ad libitum access to commercial layer mash.Experimental setup: At week 25 of age, all birds were inoculated with 35 northern fowl mites (Ornithonyssus sylviarum) on their abdomen. Also, hens received a dust box (0.102m2 surface) with playground sand (2.2 kg) or no substrate at 24 weeks of age. The rest of the cage consisted of conventional wire.Measurements: Mite infestation and behavior. Although the experiment already ended, behavioral data still needs to be collected. Video recordings were conducted with infrared cameras mounted in front of every cage, with 50-70 cm distance from the cage. Preparations will entail training of students to code video material. Behaviors will be recorded for 8 hours per night, from 22.00h until 06.00h, resulting in 512h of behavioral observations per treatment group. Data will be analyzed with mixed models in Genstat.Methods and Procedures Project 4This experiment was approved by Virginia Tech IACUC (protocol 18-124). The euthanasia methods will be applied to broilers between 35 and 43 days old. The minimum total number of birds used in this experiment will be 200. Birds will be housed according to commercial standards and university animal care research guidelines.Measurements: We will assess the impact on animal welfare based on time to unconsciousness, latency to death, number of kill attempts needed (kill success), and severity of injury obtained. We will assess the feasibility based on a self-evaluation for ease of use and safety, and we will calculate equipment acquisition and operation costs. Data will be analyzed with mixed models and post-hoc adjustments in SAS.Manual cervical dislocation: We will perform the manual cervical dislocation by holding the bird's legs in one hand, close to the hip with the underside of the bird's body against the thigh. We will use the first two fingers to grasp the head behind the skull. We will then stretch the neck downwards, at the same time pressing the knuckles into the neck vertebrae and pulling the bird's head back, with one, swift pull.Mechanical Cervical Dislocation: We will administer mechanical cervical dislocation using a Koechner euthanizing device previously developed for use on chickens and turkeys. The method will be administered to live birds followed by the stated physical and behavioral assessments.