Saturday, March 2, 2013

Opinions On Lengthening Light

Christel writes: I often read about a sudden increase in daylight hours, from 10 to 15 hours in one step, apparently with success. But from dr Coutteel, Belgium, I read:

The Role of Daylight Length
Most problems in canary breeding are due to errors in the manipulation of the light cycle. Canaries need a minimum of 14 to 15 hours of daylight to begin breeding (nest building and production of eggs). With this amount of light, they are also able to feed their youngsters adequately and raise them properly. The cycle of light is also a major factor in determining whether breeding is sustained. If the length of daylight is submitted to fluctuations, the birds may receive conflicting hormonal incentives and negative endocrine feedback. The result can be an early molt and the birds may cease breeding. There are two methods of manipulating the length of daylight [18].

Gradually Increasing Daylight Length:
Using this technique, the amount of daylight is gradually increased on a weekly basis. Depending on how quickly this is done, it may take a period of 2 months to extend the 8 to 10 hours of natural daylight to 15 hours. If a weekly addition of 30 minutes (5 additional minutes per day) is used, it will take approximately 10 weeks to obtain this result. This means that the fancier needs 2 to 3 months preparation before breeding can begin. Gradually increasing the length of the day is closest to natural stimuli and is used by more than 80% of the fanciers. Fifteen hours of daylight length appears to be ideal. Poor annual breeding results with higher chick mortality occur when the daylight length exceeds 17 hours.

Immediate Increase to Full Daylight Length:
The daylight length can also be increased suddenly from 10 to 15 hours. In this case, the birds reach breeding condition after 3 to 4 weeks, but most are unable to maintain good results throughout the full breeding season. However, some fanciers do have good results with this method. This method of sudden increase, used by approximately 10% of the breeders, often leads to poor fertilization of the first clutch, which normalizes subsequently, and higher mortality of females.

This worries me.

Would be happy to reading your view on this.

Big Bird: Thanks so much Christel for sharing this with us, it is well written by a knowledgeable person. I agree with most of what is written here by Dr. Coutteel, Belgium. 

It is critical if we want to breed earlier in the year, that we extend our bird's day length to a minimum of 14 to 15 hours.  Smaller varieties will breed on as little as 12 hours but much better results is obtained when even they are breed at 14 to 15 hours. One very successful colorbred breeder uses 16 hours and it works very well for him.

Longer day hours is one of the three factors: lighting, temperature, and feeding that brings birds into breeding condition. Using longer days for breeding also helps reduce chick mortality as the parents feed more hours per day.  

An very important point is to avoid dropping the the day length until molting is desired as dropping the day length changes hormones and precipitates molt. This is very important when you sell or purchase birds. Always find out the day length from the seller and maintain or extend it. I commonly send good pet quality birds to Trinity Bird Gallery in Colorado Springs and Anna makes sure that the day length is the same or longer to accommodate them. The importance of day length is shared with the purchaser who if unaware of the effect of day length on the bird's help would wonder why their bird is sick when they have had it only a year. Often they write me, "Why is my male not singing?" And when you get to the bottom of the problem, it is erratic lighting pattern. "Does the bird go to bed with the sun and get up with the sun, I ask? Yes, they often say, I cover him most every night and uncover him in the morning. Do you sometimes sleep late on the weekend? Oh.... How about not covering the bird and letting the light coming through a window get him up and put him to bed? Don't keep him up late in the family room etc. As dusk move him to a room that will be dark till sunrise.

Recently, I sent a couple of German roller pairs that were ready for breeding to a breeder in Texas. Before I agreed to send them, I cautioned him that they would need to be on a minimum 14 hours plus 30 minutes dimmer. He agreed, I sent them, the birds arrived in great breeding condition, a phone call a couple of days later, revealed that "he knew best" and was gradually decreasing their hours so that they could breed with his birds on 12 hours. I was just sick, as the birds are going to be very confused, and I told him had he been honest with me on his intent, I would never have sent them to him.  Oh well.....

Gradual increasing day length and immediate increasing require different skill levels. Gradually lengthening day length is easier providing you do not over stimulate with foods. I have done experiments using just one of the three factors each one can bring them in but by far what works best is the right touch with all three. When I used this method, I aimed for pairing on March 8th. I still think that where I live, that is the natural pairing day here in Kansas.

When the light is changed suddenly, the hormone levels change dramatically with cocks being more fertile and hens are encouraged to start laying in 3 or 4 weeks. If possible, cocks can be changed in a separate area 3 weeks before the hens. Mine are in one aviary so I start the cocks on high doses of vitamin E, given once a week, three weeks before the hens and breeding foods without animal protein (egg) and do the sudden lengthening to 14 hours plus 30 minutes dimmer when I start the first dose of vitamin E on the hens which is when the cocks get their fourth dose. 

Where day length and territorial fighting are critical for cocks, the breeding behavior of cocks is the number one factor for bringing in the hens. Changes in diet can stimulate hens to prematurely lay infertile "heat" eggs, an error in over stimulating the hen is more apparent when the lights have been changed suddenly. Experienced breeders avoid overstimulating the hen with food and keep temperature below 65 degree F to move the hen forward but only when the cock is ready to play his role in stimulating her. Experience teaches us to recognize  the darker blue single heat egg from laying a normal fertile clutch and so we toss the "heat" eggs and ignore the temptation to set a hen who fooling us. Should you set them up laying "heat" eggs naturally you will be disappointed.

The easiest way to bring the hen in full breeding condition is using a divider and only feeding cock the delicious new breeding foods. When she is ready she will beg him to feed her through the wire and success is just a divider away. She will continue begging and he will feed her and mating will likely occur shortly. Mating several days before egg laying produces the most fertile eggs.

To sustain the breeding season, once the birds are setting on fertile eggs and things seem near perfect, I move the day length 30 more minutes and again in a couple more weeks until it is 15 hours plus the 30 minute dimmer. If I want, my birds will still breed well in June and quit on their own around the 4th of July. I have even had fertile clutches when the male is clearly molting on the wing butts. So I do not have problems sustaining good results. I also have never seen higher mortality of females. I imagine Dr. Coutteel is referring to older hens death. Prolapsed uterus in older hens occurs in both methods and is fatal.

Breeding canaries requires learning to work with your birds and being the facilitator. Do you always get it exactly right? No but if you understand your birds you know what is needed. Often people want me to put out a feeding chart etc. That is not how it works for me, generally I move with them into breeding condition but I always take my lead from the Birds!


Anonymous said...

Great article..

Anonymous said...

Hi Linda,Thanks for a wonderful article on lighting.In SA where I live the max daylight is 14 hours and 25 minutes.This year I will gradually increase the daylight hours.I have had mixed success with the instant 14 hour lighting.
What would you reccomed for a flight cage to keep young birds in good shape(keeping the fat off),a upright cage 7ft high or 7ft long.I prefere the 7 ft high for the breeding season.
In SA we have to mix our own seed mixes and do not have your variaty of seeds.

Linda Hogan said...

Exercise certainly helps keep weight off. I would be sure to have many divided perches to minimize perch fighting.