In his presentation at the Turkey Science and Production conference in the UK this year, Dr Dennis Bauman, Technical Services Specialist with Hybrid Turkeys in Canada focused on what he sees as two of the most common and important challenges encountered in the turkey breeding industry, namely failure to peak or to maintain peak egg production and drops in fertility.

Failure to Peak or to Maintain Peak

Weight is determined by the feeding programme for the first 30 weeks of life, and Dr Bauman stressed the importance of ensuring targets for weight are reached each week. This requires weekly weighing of a representative sample of hens to ensure accurate weights, and then feeding the females according to weight and not age.

If the birds are exceeding the target, they should be moved to the next ration earlier and if they are too light, they should be held on the higher–specification diet for longer. It is important to make these changes as soon as the birds diverge from the standard, and not to wait for peak production before taking action, he said. The ideal bodyweight is plus or minus five per cent from the goal.

Experience has shown flocks that overshoot the bodyweight target and are then held back do not peak well so it is important to monitor bodyweight weekly during conditioning. Even if such flocks are allowed to stay on a higher weight curve, the hens are likely to have excessive abdominal fat and be generally unfit, increasing the likelihood of prolapses, double–yolked eggs and egg peritonitis.

Just because a flock may be at target weight as the birds enter the laying barn, there is no guarantee of success, said Dr Bauman. What is more critical, he said, is how the flock arrived at that weight, which reflects body composition and level of fitness.

Data from those companies that monitor bodyweights throughout lay shows the importance of bodyweight on both peak egg laying percentage and sustained production. Dr Bauman said longer peaks and overall higher egg production appear to be correlated with the lowest bodyweight losses after the onset of production. More research is needed to improve the intake of feed and nutrients in the first six weeks of egg production, he said.

Lighting – especially light spectrum – during conditioning plays a role in reproduction, according to Dr Bauman. For optimum results, he recommended fluorescent lights in the 630nm range. Incandescent and compact fluorescent cool lights and those of low intensity (4 foot candles) are associated with poor peaks. These aspects are often overlooked when there are issues over poor egg production, he said, and the issue is occurring more often as the result of recent energy–saving initiatives.

Under field conditions, feathering problems may be observed if the lighting is wrong for the hens during conditioning and if during lay, sexual maturity and the start of lay may be delayed and/or poor peak performance achieved.

Drops in Fertility

Trouble–shooting drops in fertility requires the routine collection and analysis of information by the farm manager, insemination crew leader and hatchery quality control personnel, said Dr Bauman. He explained that fertility problems are often multifactorial and may take time to solve.

“The sooner you begin, the sooner the problem will be solved,” he said.

He suggested firstly ascertaining whether the issue is one of a drop in fertility or an increase in early dead embryos. To detect fertility in a timely manner, Dr Bauman suggested carrying out routine egg break–outs to determine true fertility, collecting 50 to 100 eggs per house over a seven–day period. After removing eggs that are double–yolked, dirty, small or misshapen, the rest should be set in a small portable incubator and broken 48 and 72 hours after setting.

The results need to be passed on to the AI crew so that the semen dosage can be adjusted or, in case of more severe fertility drops, the breeder manager should be informed so that an investigation can be started. The information may identify whether the problem is linked to one house, one or more farms, breeders of a specific age and/or one AI crew.

Where a fertility problem is suspected, there are two broad areas for further investigation:

• Poor quality semen or lack of semen
  Males should be checked for loss of bodyweight: this could be due to feed/nutritional or disease problems. Feed problems could explain a fertility issue as multiple farms with the same feed supplier. Incorrect lighting programmes or low light intensity, e.g. from burnt–out lights in one area, could be the root cause.
  
  
• Improper insemination techniques
  Urates or faecal contamination may indicate poor milking procedures, and a semen filter is necessary. Insemination techniques may need to be improved. Good protocols and documentation that these have been followed will help identify if a problem is related to one batch, or lot of extender. Periodic semen analysis of on–farm males is worthwhile as it can now be carried out easily and efficiently in minutes.

Conclusions

Dr Bauman put forward three take–home messages from his presentation.

Firstly, he stressed the importance of well documented and regularly audited monitoring programmes. “If information is worth collecting, it is worth analysing and reacting to,” he said.

Second, with the economics in the industry today, one cannot afford to be complacent and wait to see if a problem resolves itself.

And finally, he added, at least the same mistake should not be repeated in subsequent flocks.

July 2012