The egg yolk sac in chicks is not a complete replacement for food, but rather a supplement. It’s designed to be used alongside food and water, except during the immediate hatching and recovery period. While the yolk sac sustains chicks during this initial phase, it’s crucial to understand their nutritional needs beyond it.
Following hatching and recovery, the yolk sac provides vital nutrients for rapid growth and helps chicks transition to exogenous food and water over a few days. However, during the first three days, it only contributes about 10-30% of their total energy and protein intake. The exact proportion depends on how much food and water the chicks consume.
The yolk sac depletes quickly. Laying breed chicks absorb approximately 40% within the first 24 hours, 60% within 48 hours, and 80% within 72 hours. Broiler chicks absorb about 45-55% in the first 24 hours, 65-70% within 48 hours, and 80% within 72 hours. This shows broilers have a slightly better initial yolk sac utilization, but laying hens catch up by day three.
Interestingly, studies suggest that chicks allowed to feed absorb their yolk sac more rapidly than those deprived of food. This might be due to greater intestinal activity in fed chicks, promoting quicker absorption of the yolk. This phenomenon has been observed in both broiler and laying hens.
Think about it: chicks with access to food and water within 6-24 hours post-hatching also access yolk sac nutrients faster. It’s like a “nutrient boost,” including earlier absorption of crucial minerals, amino acids, protein, and lipids.
On the other hand, food-deprived chicks, like those shipped without immediate access to sustenance, rely solely on their yolk sacs for an extended period and miss out on this early “nutrient boost.”
Food-deprived chicks experience significant weight loss within 48 hours of hatching. They weigh considerably less than their fed counterparts. This weight loss is consistent across broiler, layer, and dual-purpose breeds.
It’s surprising that some still believe chicks obtain everything they need solely from their yolk sac!
Early feeding in newly hatched chicks has various advantages over food deprivation, ensuring optimal growth and development. While the temperature of the food isn’t specifically addressed in these studies, ensuring feed is readily accessible and of high quality is paramount for the health of young chickens. Considering young chicks require warmth to thrive, providing slightly warmed food could further encourage consumption, especially in cooler environments, but is not a strict necessity. The primary focus should be on ensuring the food is fresh, nutritious, and easily accessible.
In conclusion, while the yolk sac plays a vital role in the initial days, providing chicks with early access to food and water is crucial for their growth and development. The temperature of the food is less critical than ensuring its accessibility and nutritional value, though slightly warming the food could be beneficial in some situations.
