Essentials of a Hatching Egg Quality
A Hatching Egg Quality Assurance Program (QAP) will be cost effective in preventing a loss of hatch for long periods of time and will help to maintain the quality of the chick placed in the field. A Hatching Egg QAP prerequisite is communication and the feeling of shared responsibility between the hatchery, breeder service, and broiler service.
The objective of a Hatching Egg QAP are to promote chick quality and to help the operation maintain optimal chick yield from the breeder house. A Hatching Egg QAP will require:
The collection of data for evaluation of the conditions to which eggs are subjected.
The utilization of the data to improve and maintain optimal conditions in the hatchery and to develop a profile of efficiency for each breeder flock.
The routine administration of the program elements.
Communication among the individuals involved.
Factors evaluated to obtain data are:
At the hatchery
Inspection for cleanliness and sanitation, monitored by microbial plating.
Vaccine mixing and handling with special emphasis on factors leading to heavy bacterial loads in chicks.
Egg quality from the farm.
- Egg breakout.
At the farm
- Inspection of egg handling and storage conditions
At the Hatchery
The Hatching Egg QAP will be performed at different times and at different frequencies. Evaluation of cleanliness and sanitation should be performed only after clean-up has occurred. This will indicate the effectiveness of the current sanitation program. Try to work the inspection around the work schedule of hatchery personnel, beginning the inspection where the least activity is taking place. The inspection should be similar to the following.
In the egg room, the first items to check are the room temperature and humidity levels. The record of these measurements for the past several weeks should be reviewed. The room should be checked for general cleanliness in the following areas: walls, ceiling, floor, vents, ducts, fans, cabinets and shelves, filters, doors, and light fixtures. Findings should be recorded on a check list. Find five empty farm racks that the hatchery is returning to the breeder farms and check for cleanliness. Make a written record of the collected information.
Monitoring of bacterial contamination in the egg room should be routinely conducted with air plates or a mechanical air sampler. The monitoring of shell contamination is not necessary unless there is a severe contamination problem which requires quantifying to aid in problem solving. Total shell washes as described by Gentry and Quarles would aid tremendously in quantitatively following improvement in egg handling practices. All eggs have shell surface contamination unless they have been thoroughly sanitized. To roll an egg on an agar plate will not provide a meaningful value of bacterial contamination, and the use of egg washes as a routine procedure is time consuming.
A regular program of grading eggs which includes observations on the incidence of cracked, dirty, stained, and upside down eggs is helpful as is a record of egg age. If there appears to be a problem with excessive debris on the eggs or egg racks entering the hatchery, it may be helpful to have a compressed air hose handy to blow off the debris before bringing the racks into the egg room. If cracks become a problem, the source of the cracks may be determined by candling a sample of three hundred eggs on the farm and again at arrival in the hatchery. Hairline cracks in a flock greater than 45 weeks old can pose a problem.
Checking the internal egg temperature upon arrival of eggs at the hatchery may be advisable periodically, especially during the warmer months when pre-incubation is more likely to occur. However, during the cooler months the monitoring of internal egg temperature may not be critical.
Specific gravity determination on eggs arriving at the hatchery may be performed if a shell problem becomes apparent and there is a need to determine the effectiveness of the corrective action. Performing routine specific gravity measurements may have limited value if other egg quality checks which are less time consuming are being performed regularly.
In the setter hall check for cleanliness in the following areas: doors, lighting, floors, ceilings, vents, ducts, air filters, and walls. Select two areas in the hall and monitor microbial contamination using air plates or a mechanical air sampler.
Check the setters visually for cleanliness in the following areas: floors, walls, ceilings, fans, fan boards, racks thermometers, doors, nozzles, exhaust ports, vents, ducts, tops, and control panels. The machines should be evaluated for microbial contamination in a minimum of five setters in each hall. Enter each one while leaving the machine running and use an air plate or mechanical sampler to monitor microbial contamination of the air in the center of each machine. Make sure all fans and alarms are on when you enter so that the incubator's environment is not disturbed. Check that the turners, humidifier nozzles, and the aerosol sanitizer nozzle are working properly.
In the hatcher halls check for cleanliness in the following areas: doors, lighting, floors, ceilings, vents, ducts, air filters, and walls. Select two areas in the hall and evaluate for microbial contamination with air plates or a mechanical air sampler. The air samples should be taken before transfer is made, selecting a minimum of five hatchers per hall. As a follow-up, check on hatcher sanitation. Test five areas inside a hatcher using Rodac plates or swabs. Any of the following areas may be tested: walls, ceilings, doors, fan boards, fan guards, fan blades, nozzles, air intake ducts. To conclude the hatcher inspection, five hatching trays should be examined for cleanliness and dryness. Trays should also be checked for microbial contamination using Rodac plates or swabs.
It is important that the individuals who record wet and dry bulb temperatures communicate abnormal readings directly to the manager. Failure to communicate abnormal readings may result in lower chick quality or reduced hatch.
After being cleaned and disinfected the chick room is inspected in the following areas: walls, ceilings, floors, vents, ducts, fans, cabinets, shelves, filters, doors, and lighting fixtures. Microbial contamination is checked using surface swab or Rodac plate samples. Two samples should be taken from the chick belt, the Chick Go-Round and one sample should be taken from each chick slide. A sample from the sexing table is collected in hatcheries where applicable. Microbial contamination should be monitored in the air from two locations, the chick processing area and the chick holding area.
Examine the vaccine room for cleanliness in the following areas: walls, ceilings, floors, doors, vents, ducts, cabinets, shelves, filters, and lighting fixtures. Collect one air sample for microbial contamination monitoring in this room. With a sterile syringe, pull 0.5 cc diluent per bottle from three bottles mixed for the next day's usage and plate for microbial contamination.
Monthly records for vaccination misses per 1000, beaktrimming error percentage and vaccine dosage checks should be examined. Observe vaccine mixing and handling and check the following:
Amount of time needed to thaw vaccine.
Number of ampules thawed at one time.
Temperature of thawing H2O.
Vials and tops rinsed with diluent.
Length of time to use vaccine mixture.
Use of protective gloves and face shield when handling vaccine.
Small cups placed over aspirator bottles while in use (where applicable).
Cleanliness of Marek's injectors.
Frequency of vaccine bottle change (where applicable).
Frequency of tubing changes.
Maintain a written record of this information.
Use a sterile syringe to collect 0.5 cc of Marek's vaccine mix per bottle from 3 bottles prior to use in the chick room and plate for monitoring microbial contamination. Collect Marek's vaccine samples from 50% of machines on an open system and 25% on a closed system. Have one dose of vaccine per machine injected onto a plate. Collect Beak-O-Vac samples (if used) from 10% of machines in the same manner. To monitor the spray cabinet, place a sterile plate in a chick box and activate the spray.
Tray Wash Room
Examine the tray wash room in the following areas for cleanliness: walls, ceilings, floors, vents, ducts, fans, filters, doors, and lighting fixtures. The access hallways should also be evaluated during the inspection for general cleanliness in these areas: walls, ceilings, floors, vents, ducts, fans, filters, doors, lighting and fixtures.
Chemical Storage Area
Check the Chemical Storage Area to evaluate for safety and proper handling. Containers should be properly labeled and evidence of spillage should be checked. Safety equipment such as goggles, gloves and rubber aprons should be readily available.
Evaluate the Chick Bus for overall cleanliness and record observations. Areas evaluated should be floors, fans, wells, air vents, and windows.
Roof of the Hatchery
On the roof of the hatchery, check the evaporative coolers, making sure that pads and H2O are clean, and that the pads are unobstructed by mineral deposits. Evidence of disinfectant present should be evaluated in coolers (foam). Record observations on a checklist.
Egg Breakout Program
It is critical that an egg breakout program be performed on a regular basis. Each flock should be examined by residue breakout at least once per month. If the situation warrants, fresh egg or candling breakouts may be performed. It is also important that the data collected from the breakouts be placed in a format that can be easily retrieved and the individual flock history can be referenced over time and compared to performance standards. The breakouts are time-consuming and are usually the first thing deferred when time is limited. However, breakouts are necessary to prevent deterioration of flock performance. A critical item often overlooked when performing breakouts is the number of eggs missing between the number set and the number in the hatching tray. It is extremely important that the chicks be counted out of each tray from which the residue is being examined to determine the true hatch of the tray. Failure to do so may skew the hatch assessment from the sample and cause you to look in an erroneous direction when problem solving. Additional information which should be obtained on hatch days is an assessment of the time of hatch, the duration and evenness of hatching time for the various flocks as well as chick quality factors.
Inspection for the proper operation of setters and hatchers should be made once per month or when in suspect of malfunction. A quality thermometer should be used to check the accuracy of the machine thermometers. Proper environmental settings in the rooms and operation of the hatchery ventilation system must be constantly monitored.
Discussion between the hatchery manager, assistant manager, and any other supervisory personnel of any problem areas found during the inspection is critical.
At the Farm
It is advisable that all farm egg rooms have a set of guidelines for cleanliness and standard operation. The egg room environment and breeder house nesting conditions should be inspected on a regular basis and a written record maintained.
A Quality Assurance Program is only as good as the effort that is put into maintaining it on a regular basis. There must be a commitment from all individuals involved to make it succeed. Regular Quality Assurance Meetings (1 or 2 per month) between the hatchery manager, breeder manager, and broiler service manager are a must. The meetings at times may include all or some of the breeder and service personnel. At these meetings, problems with breeder and broiler flock performance should be discussed to supplement the information gathered at the hatchery as well as chick necropsy records from the diagnostic lab, chick delivery records, and broiler house chick mortality records. These meetings must be entered into with the idea of cooperation and problem-solving; the meeting is not to be a forum to point blame in anyone's direction.
Michael J. Wineland, Extension Poultry Specialist
North Carolina State University
10/91, PS Facts #7