New analysis, funded by the Canadian Poultry Analysis Council, seeks to keep up hen well being via longer lay cycle.
For laying hens, sturdy bones and good egg shell high quality each require phosphorus and calcium – two important minerals that journey from the hen’s physique to her eggs over time. Consequently, on the finish of a 70-week lay cycle, a hen’s provide of minerals in bone could also be depleted resulting in weaker bones. Now, Marie-Pierre Létourneau-Montminy in Laval College’s Animal Science Division is main a world multidisciplinary analysis crew on two concurrent initiatives that purpose to know how calcium and phosphorus journey via a hen’s physique at numerous levels of the life cycle, and the way precision mineral feeding would possibly assist meet day by day mineral necessities that may enable producers to increase a lay cycle.
“We’re working to foretell day by day diet necessities of laying hens in calcium and phosphorus,” says Létourneau-Montminy. “We now have a modeling challenge that, for the primary time, collates all obtainable printed knowledge to present us a greater understanding of the destiny of calcium and phosphorus in the gastrointestinal tract after which at metabolic ranges. And concurrently, we’re in a position to take a look at the mannequin’s predictions in a 100-week analysis trial.”
Limestone particle measurement issues
To simulate the destiny of those minerals, the crew first needed to perceive the extent of labor that had already been completed to trace phosphorus and calcium within the digestive tract of a laying hen. The researchers confronted an surprising hurdle after they realized there was no info referring to the interplay between limestone particle measurement (a supply of calcium) and phytase in laying hens, an enzyme that makes phosphorus from vegetation. Analysis companions in France carried out a trial that supplied info to handle the hole.
“We confirmed massive limestone particles work together much less with phytase, and advantageous particle measurement will cut back the effectivity of the enzymes,” says Létourneau-Montminy. “Bigger limestone particles keep within the gizzard longer, and since eggshells kind at evening when the hen eats much less, they’re an obtainable supply of calcium. That is significantly essential as a hen ages, and makes much less environment friendly use of calcium.”
From there, the researchers have been higher in a position to predict phosphorus and calcium absorption. Typically, the hen has to take some calcium from the bone to deposit within the egg’s shell throughout the evening, and that course of delivers phosphorus, which is then misplaced in manure. With the modelling examine knowledge, the crew was in a position to predict day by day diet necessities all through a hen’s life cycle – and even optimum time of day.
Measuring bone well being
For the second a part of Létourneau-Montminy’s challenge, the researchers are placing the mannequin predictions to the take a look at by elevating laying hens to 100 weeks with two completely different dietary phosphorus ranges. The crew is utilizing a bone scanner device generally utilized in human medication for osteoporosis analysis to check the hens’ bones for mineral content material in addition to physique composition in fats and lean. Létourneau-Montminy hopes the challenge will give a greater understanding of how bone evolves, and the quantity of calcium that transfers to eggs as hens age.
“With age, the birds enter osteoporosis and so they make much less environment friendly use of calcium,” says Létourneau-Montminy. “We additionally are likely to see a discount of phosphorus.”
The significance of precision phosphorus
Létourneau-Montminy notes with world phosphorus reserves affected by rising costs and shortage, producers face growing strain to be exact with this non-renewable useful resource. When the trial completes in November 2022, she hopes to have a greater understanding of precisely how phosphorus and calcium are used within the hen’s physique over time.
“We all know that with getting older, hens use extra of their bone reserves, so we’re completely different methods,” says Létourneau-Montminy. “With this trial we could have essential details about how mineral necessities change, and we could have many knowledge factors to assist us fill in a number of the information gaps.”
Birds sometimes lay 350 eggs by the tip of their 52-week cycle. By extending to 70 weeks of lay or 100 weeks of age, the purpose is to get to 500 eggs, so long as the information helps the birds are in good bodily form. She notes the crew is gathering details about bone composition, bone marrow density, mineral content material in eggs and bones, in addition to hormone ranges in bloodwork over time.
Each the modeling challenge and the analysis trial might be accomplished by early 2023. Létourneau-Montminy hopes to finish an analogous trial utilizing the identical design vitamin D concentrations in eating regimen and in layer hens.
