Fahrig Brooke M, Mitchell Mark A, Eilts Bruce E, Paccamonti Dale L
Department of Veterinary Clinical Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
J Zoo Wildl Med. 2007 Mar;38(1):7-12. doi: 10.1638/05-098.1.
The phylogenetic order Squamata has many representatives that could benefit from the use of semen preservation as a tool for assisting conservation. To date, few studies have been made evaluating the potential for collecting and preserving semen from snakes. The objectives of this study were to characterize semen parameters of the corn snake (Elaphe guttata), including appearance, volume, concentration, sperm motility, and sperm morphology, and to determine the longevity of corn snake sperm motility stored at 4 degrees C. Single semen samples were collected from 22 adult corn snakes. The appearance of the corn snake semen was generally cloudy, and the color was white to tan. Corn snake spermatozoa initially exhibited a median motility of 92.5%. Corn snakes were found to produce small-volume ejaculates (median 0.01 ml). However, the overall concentration of the snake ejaculate was high (chi = 852 x 10(6) +/- 585 x 10(6) spermatozoa/ml). Morphologically, a mean of 75.7 +/- 9.3% of the sperm cells in an ejaculate were normal. Snake ejaculate with a white appearance had significantly higher sperm concentrations (chi = 1,859 x 10(6) +/- 1,008 x 106 sperm cells/ml; F = 15.74, P = 0.001) than tan ejaculates (chi = 601 x 10(6) +/- 439 x 106 sperm cells/ml). Sperm motility decreased significantly in samples that were stored at 4 degrees C for greater than 48 hr in a refrigerator or Equitainer I. This is the first study to characterize semen volume, appearance, and concentration; sperm motility; and sperm morphology in captive corn snakes. The information derived from this study can be used to develop a model for a collection, cooled storage, and shipping program for semen from endangered or threatened captive and wild snakes.
有鳞目在系统发育顺序上有许多物种，可受益于将精液保存作为辅助保护的一种手段。迄今为止，很少有研究评估从蛇类收集和保存精液的潜力。本研究的目的是描述玉米锦蛇（Elaphe guttata）的精液参数，包括外观、体积、浓度、精子活力和精子形态，并确定在4℃下储存的玉米锦蛇精子活力的持续时间。从22条成年玉米锦蛇收集了单个精液样本。玉米锦蛇精液的外观通常呈浑浊状，颜色为白色至棕褐色。玉米锦蛇精子最初的活力中位数为92.5%。发现玉米锦蛇产生的射精量较少（中位数为0.01毫升）。然而，蛇类射精的总体浓度较高（χ=852×10⁶±585×10⁶个精子/毫升）。在形态上，射精中平均75.7±9.3%的精子细胞是正常的。外观为白色的蛇类射精的精子浓度（χ=1859×10⁶±1008×10⁶个精子细胞/毫升；F=15.74，P=0.001）显著高于棕褐色射精（χ=601×10⁶±439×10⁶个精子细胞/毫升）。在冰箱或Equitainer I中于4℃储存超过48小时的样本中，精子活力显著下降。这是第一项描述圈养玉米锦蛇精液体积、外观和浓度、精子活力以及精子形态的研究。本研究获得的信息可用于开发濒危或受威胁的圈养和野生蛇类精液的收集、冷藏保存及运输方案模型。
