Padalino B, Rateb S A, Ibrahim N B, Monaco D, Lacalandra G M, El-Bahrawy K A
Department of Veterinary Medicine, University of Bari Aldo Moro, Valenzano, Italy.
Division of Animal and poultry production, Desert Research Center, Cairo, Egypt.
Theriogenology. 2016 Jun;85(9):1644-1651. doi: 10.1016/j.theriogenology.2016.01.027. Epub 2016 Feb 5.
This pilot study was conducted to test the hypothesis that female camels behave differently in various ovarian phases in the presence of a restrained male camel. The aim was to identify behavioral patterns which could be used as indicators to detect ovulatory phase by visual observation in the presence of a restrained virile bull. Twenty-four healthy, nonpregnant, and nonlactating adult females were used. Transrectal ultrasonography was performed for each animal once a week over a 3-week period to determine the phase of the ovarian cycle. Females were considered to be in the ovulatory phase (O) when there was at least one preovulatory follicle (12<Ø<19 mm) protruding from the ovarian surface, and in the nonovulatory phase (NO), when growing follicles, regressing follicles, or corpora lutea were detected. Immediately after examination, each female was freely exposed to a restrained bull for 15 minutes, and her behaviors were filmed. The videos were analyzed through a focal animal-sampling ethogram (states: looking at the male; looking outside; standing close to the male; searching; and lying down; events: interaction with the male; urination; defecation; sound emission; and steps). A score for tail position (tail score: 1 = close to the vulva, 2 = horizontal, 3 = vertical) and for interest in the bull (male time score: from 1 to 5; 1 = <20% of observation period spent near the bull; 5 = more than 80%) were recorded. Ovulatory phase camels showed higher interest in the male than nonovulatory phases: they stood close to the male for longer periods (P = 0.0159), interacted with the male more frequently (P = 0.0004), and tended to lie down in front of him (P = 0.1202). Moreover, ovulatory phase had a significant effect on male time score (P < 0.01), mature follicular ovarian phase being associated with higher scores. Seeking the male has already been proposed as a behavioral indicator of estrus in camels, this has now been confirmed using a standardized ethogram. The present results clarify that camels behave differently in different ovarian phases and that monitoring their behavior in the presence of a restrained bull could help detect their ovulatory phase. This would have profound implications for enhancing fertility in dromedary camels by improving timing of mating or artificial insemination.
在有一头被束缚的雄性骆驼在场的情况下，雌性骆驼在不同卵巢阶段的行为表现有所不同。目的是识别出在有一头被束缚的强壮公牛在场时，可通过视觉观察用作检测排卵阶段指标的行为模式。使用了24头健康、未怀孕且未哺乳的成年雌性骆驼。在3周的时间内，每周对每头动物进行一次经直肠超声检查，以确定卵巢周期的阶段。当卵巢表面至少有一个排卵前卵泡（12<Ø<19毫米）突出时，雌性被认为处于排卵阶段（O）；当检测到生长中的卵泡、退化的卵泡或黄体时，则处于非排卵阶段（NO）。检查后，立即让每头雌性自由接触一头被束缚的公牛15分钟，并拍摄其行为。通过焦点动物取样行为谱（状态：看向雄性；看向外部；靠近雄性站立；搜寻；躺下；事件：与雄性互动；排尿；排便；发声；以及走动步数）对视频进行分析。记录尾巴位置得分（尾巴得分：1 = 靠近外阴，2 = 水平，3 = 垂直）以及对公牛的兴趣得分（雄性时间得分：从1到5；1 = 在公牛附近度过的观察期少于20%；5 = 超过80%）。与非排卵阶段相比，处于排卵阶段的骆驼对雄性表现出更高的兴趣：它们靠近雄性站立的时间更长（P = 0.0159），与雄性互动更频繁（P = 0.0004），并且倾向于在雄性面前躺下（P = 0.1202）。此外，排卵阶段对雄性时间得分有显著影响（P < 0.01），成熟卵泡卵巢阶段得分更高。寻求雄性已被提议作为骆驼发情的行为指标，现在已通过标准化行为谱得到证实。目前的结果表明，骆驼在不同卵巢阶段的行为表现不同，在有一头被束缚的公牛在场时监测它们的行为有助于检测其排卵阶段。这对于通过改善交配或人工授精的时间来提高单峰骆驼的繁殖力具有深远意义。
