孵化

Fertile Eggs

The nucleus of the female cell is a small white or light-coloured speck about the size of a pinhead that is located on the top side of the yolk. Here the microscopic male sperm cell finds lodgement and the cells are united to form the embryo. A fertilised egg is characterised by a white ring 3-4 millimetres in size on the yolk surface (germ cell), whereas an infertile egg is characterised by a single white speck of about 2-3 mm diameter.

肥沃的雞蛋應儲存下來

Fertile Egg Storage

肥沃的雞蛋應幹淨幹燥,並以75%的相對濕度在12-15°C之間儲存,而小末端降低。

Eggs should be turned by 90 degrees at least once to twice daily. Optimal hatchability is achieved in fresh eggs less than 10 days old, but reasonable hatchability can be obtained in eggs up to 14 days of age. Fertile eggs should maintain a relatively constant weight with minimal weight loss during storage. Temperatures above 25°C can initiate cellular replication of the germ cell on the yolk of the fertile egg and will increase embryonic mortality and reduce hatchability. Temperatures below 10°C can inactivate the germ cell.

Principles of Artificial Incubation of Fertile Eggs

孵育優質肥沃雞蛋的四個主要要點是:

  • Correct and even temperature controlled by a thermometer or thermocouple
  • Correct humidity controlled by ventilation rate and water application
  • 通過通風控製的正確氧氣和二氧化碳濃度
  • 每天通過手動或自動手段將肥沃的雞蛋轉動大約90度。

如果孵化器製造商的操作說明仔細遵守,則可以輕鬆地實現和維護這些參數。

孵化Temperature Range and Variation

孵育的溫度要求在Table 1(下圖)和大多數孵化器的溫度變化為0.2-0.4°C,可有效孵育,隨後具有高孵化率。

對溫度以上1°C以上或低於建議溫度的胚胎耐受性(Table 1) is low, and temperatures outside this range will result is significant embryonic mortality. Embryos are much more susceptible to temperature variation in the early and late phases of incubation.

孵育相對濕度範圍和變化

在孵化過程中,保持一致的相對濕度的維持更加困難,隻能通過通風速率,可調節的通風孔以及在孵育過程中通過地表水和水噴霧來不斷保持。胚胎對不同濕度範圍的耐受性大於溫度,但是濕度低於40%且高於90%的濕度會產生負麵影響。當將相對濕度保持在約50-65%之前,直到孵育的最後3天,就可以實現良好的孵化性,此時應增加到70-90%。

Fertile eggs are rotated in an incubator

通風和二氧化碳/氧氣濃度

胚胎生長在空氣濃度為0.4%的空氣濃度下優化,胚胎生長降低,死亡率隨著二氧化碳濃度的增加而增加。正常氣氛含有21%的氧氣和0.04%二氧化碳。孵化的雛雞最容易受到氧偏差的影響(與完整雞蛋中的雞肉和胚胎相比),這意味著通風速率和二氧化碳濃度在孵育後期最關鍵。澳门188bet网址

雞蛋轉動和旋轉

需要卵旋轉或轉彎,以確保在蛋黃上發育的胚胎不粘附在殼膜上。這種對殼膜的粘附現象通常發生在肥沃的雞蛋儲存期間和早期孵育期間(通常是第一周)。轉彎過程允許胚胎在內部白色中旋轉和滑動,並為胚胎發育提供其他營養。雞蛋轉彎應每天進行3-6次,並且旋轉數量不均勻,以使雞蛋在更長的時間內不在相同的位置。大多數孵化器將雞蛋旋轉約90度。

表1.強迫孵化器中的家禽育雞蛋的孵化期和操作條件

火雞 鴨子 肌肉
鴨子
Pheasant 幾內亞
Quail
孵化時間 21 28 28 35 28 23-28 28 23-24
孵化
溫度(°C)
37.6 37.4 37.5 37.5 37.4 37.6 37.6 37.6
濕球
溫度(°C)
29.4-30.5 28.3-29.4 28.8-30 28.8-30 30-31.1 30-31.1 28.3-29.4 28.8-30
相對濕度 (%) 56-62 51-56 53-60 53-60 60-65 60-65 51-56 53-60
沒有每天轉彎 18 25 25 31 25 21 25 21
孵化
Temperature last 3 days (°C)
37.4 37.2 37.3 37.3 37.2 37.4 37.4 37.4
濕球
Temperature last 3 Days (°C)
32.2-34.4 32.2-34.4 32.2-34.4 32.2-34.4 32.2-34.4 33.3-35 32.2-34.4 32.2-34.4
Relative Humidity last 3 days (%) 70-83 70-83 70-83 70-83 70-83 76-90 70-83 70-83

For still air incubators add approximately 1°C表1中建議的工作溫度。這是因為靜止空氣孵化器中的溫度計通常位於孵化器的頂部,並且有一個明顯的溫度梯度,從孵化器的頂部到底部。

Candling of Incubated Fertile Eggs

After 5-8 days of incubation, the eggs should be examined using a candling light to examine the embryo for blood vessel development (‘spider web-like’) and a dark spot. Infertile eggs are obviously clear with no evidence of blood and early embryonic death is noted by the presence of a blood ring surrounding the yolk. Infertile and early dead embryos are removed at this stage. Candling can also be undertaken at 18 days of age, where the embryo is clearly visible with a distinct dividing line between the embryo and the air cell.

In large commercial incubators, candling is not normally undertaken and there is a high reliance on fertility and egg hygiene to maintain viable embryos

雞肉胚胎開發

小雞胚胎開發 - 單擊擴大。圖片由Cobb-Wantress,Inc。提供

Figure 1. Percent weight loss during incubation period with ideal weight loss and tolerances illustrated with maximum and minimum values.

孵化期間的減肥

Eggs that contain a growing embryo will progressively dry-out throughout incubation. This results in an overall weight loss of the egg and this progressive weight loss can be objectively monitored to improve incubation success. The data below (Figure1.)是一個很好的指南。如果可能的話,應監控減肥模式,並獲得理想的減肥(13%)。

Main Incubation Failures

已經開發了現代電子技術來管理孵育過程中溫度和濕度的變化,並不斷監測這些參數並與孵化環境一起記錄。這使得可以根據胚胎死亡率分析參數,設置和孵化率之間的關係。對殼中死亡胚胎的分析也是一種有價值的問題解決工具,可幫助優化孵化實踐。

Freshly Hatched Chicks
  • 早期孵化,弱小雞,未釋放的Navels,未吸收的蛋黃囊,彎曲的腳趾,交叉的喙和殼中的高比例死亡,這表明孵化溫度過高。
  • 大開始緩慢的大小雞的晚期孵化,而帶有wrynecks的小雞是溫度太低的孵化溫度的特征。
  • 大量未捕捉的,未觸及的小雞,活的胚胎和帶有蛋白塗層的大型雛雞表明孵化濕度太高。
  • Small weak chicks with large air cells, exhausted chicks in shells that have been chipped most of the way around, and chicks glued to the shell are indications that the relative humidity was too low.

Sign up to the Echook Newsletter
for the latest from PoultryHub



Baidu
map