zoomia wrote: Actually, one can't actually say that the study debunked it. They were testing for something else entirely and all their hens started out laying. Our working hypothesis has never been that it makes hens produce MORE, just that it jump starts them into laying AGAIN.
I apologize if I missed that in the OP's post.
How old are the chickens, what latitude are they on (amount of sunlight), are they provided with extra light, any other additional additives or treats, etc.? I have no problem with any working hypothesis, it's just interesting, to me, to understand how the variable to be examined is isolated.
The point of the research, I linked to, was to determine if the `metabolism' of laying hens could be altered sufficiently, by the addition of Capsaicin, so more energy would be devoted to the business end of it (less fat=more eggs). The most interesting finding was that the utilization of Capsaicin differs significantly (particularly `effects' on `fat') between avians and mammals. To quote from the paper:
Excess adipose tissue represents a useless energy deposit in the body, and the control of fat deposition is a big concern in modern strains of meat- and laying-type chickens. Higher dietary energy concentration tends to result in an increased energy intake and greater abdominal fat deposition. The liver of laying hens exhibits greater lipid synthesis compared with that of broilers, because it synthesizes triglyceride and secretes very low density lipoproteins (VLDL) in amounts sufficient to meet a high egg production rate. However, the control of the synthesis and secretion of triglyceride and VLDL in the liver could be disturbed by the incidence of fatty liver
Force molting is successfully used to induce a pause in the laying cycle, which results in higher egg production including improved shell strength and interior egg quality in the later stage. These improvements in laying performance could be explained by the reduction of fat in the liver and uterus, because most molting regimens are initiated by fasting.
CAP enhanced the energy metabolism of rats through the beta-adrenergic action of CAP itself
and decreased perirenal adipose tissue weight
The work continues on mammals at present:
http://www.nature.com/oby/journal/vaop/ncurrent/full/oby2009301a.html
If laying hens could be fed a substance that created a mimicking of a very low grade forced molt 24/7, it might result in a slightly higher output, of higher quality eggs, over a longer period of time. For those not familiar with forced molts:
How is forced-molting done? Darrell Coloscos, general supervisor of Davao Farm, says that it is very simple to do. Layers that have to undergo forced molting should be 9 to 11 months old. If they are older, they might not be able to endure the torture they have to undergo. Darrell said that for 12 days the birds are not given any commercial feed. They are only given water to drink.
On the 13th day, the birds are each given 10 grams of feed. This is very small since the normal diet of a layer is 110 grams per day. On Day 14, the birds are given 20 grams of feed, increased to 40 grams the next day. On the 16th day from the start of forced molting, the birds are given 80 grams and on the 17th day, full feed-of 110 grams is given.
After molting, the feathers become shiny. The eggs also have thicker shells.
From:
http://www.agribusinessweek.com/forced-molting-as-egg-production-strategy/
Forced molts obviously stress the hens, and any additional stress can be disastrous:
Mondini S (1980). Cannibalism due to earthquake in laying hens after forced moult. [Cannibalismo (da terremoto?) in ovaiole da consumo in muta forzata]. Clinica Veterinaria 103(7): 456-458.
Ist. Allevamenti Zootecnici, Universita, Bologna, Italy NAL Call Number: 41.8 C61
When a previously successful method was used to induce moult in 7107 hens, 224 (3%) died in the following 10 days as a result of cannibalism. This had not occurred in the 400,000 already treated, the only difference this time being an earth tremor of intensity IV on the Mercalli scale on the day after moult induction.
Descriptors: etiology, disasters, moulting, cannibalism
Copyright
2002, CAB International
So, feed formulations by the commercial contigent of chickeneers is constantly being examined for just about anything that will decrease risk and increase production.
Though not egg related, Capsaicin was one addititive tried in conjunction with others in a bit of research of overall `performance':
