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Unformatted text preview: 1-26-06Incubation and Hatchery Management:I. Introduction-hatching eggs involves a Black Box Model“hatching” (manufacturing process)Fertile Eggs ----Day-Old Chicks(input) (output)How do we hatch chicken eggs?-Nature’s Way=broody hens(clucks)-Man’s Way=artificial setting hens (“incubators”)-importance of heat in hatching eggs, long knownEX:400B.C-Egyptians and 246 B.C-Chinese21 DAYS TO HATCH A CHICKEN EGG!(3 trimesters of 7 days)“ovipostion”—release of a shelled egg“Ovulation”---release of egg inside body--Today we hatch poultry eggs in a “forced-draft incubator”.Hatchery= Specialized Poultry Industry1. Serves as multiplier of improved breeding stock.2. Supplier of day old and started stocks3. Source of information on disease control, nutrition and management4. Supplier of vaccinations, medications and equipment5. Few cases, market outlet for eggs.Flockgroup of birdsAll In-All Outdo this b/c of disease containment…chickens get in the barn and stay there! Recent Trends in The Hatchery Industry:1. Fewer hatcheries2. larger hatcheries3. Shift from seasonal of year-around hatching4. Hatchery integration with other segments of production/marketing chain5. Shift from Midwest to SoutheastII.The Hatching EggQ. How do we measure success?Hatchability=% of total eggs set that hatch into saleable chicksQ. What’s a saleable chick?* Bright, alert, ambulatory (properly “hardening”)* No unhealed or scabby navels (improper T and RH)* No pasty vents (anus) (overheating, chilling, oxygen)* No scissor (crossed) beaks* No cut toes (hatchery accidents) or cripples* No blinded chicks* No ‘red’, ulcerated hocks or sores on top of beak (High and low RH-trouble escaping the shell)•No other deformities“Double Yoke Eggs” do not hatch!Slipsmissing a deformed chick and releasing him into the farmPiping MuscleMuscle on back of head to help break out of shell during hatchingFactors that Influence Hatchability:A. Pre Lay Factors1.Fertilityis the ability of fertilized ovum to develop•Only fertile eggs have ability to hatch!exception- parthenogenesis (turkey eggs)-Copulation (“cloacal kiss”)= male deposits sperms on everted oviduct of female-Sperm swims up oviductto infundibulumwhere union with germ spot on ovum occurs (“fertilization”)-Peak fertility = 2 weeks after first mating-Fertility declines within 1 to 2 weeks after male removal-A.I. in turkeys!-Female chickens have “sperm host glands”—holds sperm for weeks and continue to lay fertile eggs the whole time!Cell Divisions: 1stand 2ndin ISTHMUSContinues in UTERUS or “SHELL GLAND”At “ovipostion” several cells are presentDo not set eggs right away—let them alone for 4-10 days at 60-65F*The longer an egg sits, the thinner the white will be*Fertile and Infertile Egg:On Yoke there is a fertility spot, defined circle = FERTILE, diffuse circle = INFERTILE2. Factors that influence fertility ( thus, included in list of pre-lay factors that affect hatchability – since only fertile eggs hatch)•Sperm/ egg quality•...
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- Spring '07
- Physical Anthropology, chicks, fertile eggs, FERTILE EGGS HATCH