德克萨斯州南部雌性蓝牛羚（）的繁殖能力

Reproductive Capabilities of Female Nilgai () in Southern Texas.

作者信息

Granger Megan M, Hilton Clayton D, Henke Scott E, Perotto-Baldivieso Humberto L, Schofield Landon R, Campbell Tyler A

机构信息

Texas Parks and Wildlife Department, 2400 Smith School Road, Austin, TX 78744, USA.

Department of Rangeland and Wildlife Sciences, Texas A&M University-Kingsville, 700 University Boulevard, Kingsville, TX 78363, USA.

出版信息

Animals (Basel). 2024 Jul 24;14(15):2150. doi: 10.3390/ani14152150.

DOI:10.3390/ani14152150

PMID:39123676

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11311046/

Abstract

Free-ranging nilgai antelope () are an understudied species, both on their native ranges of India, Pakistan, and Nepal and on their introduced ranges in southern Texas. Basic data related to population sizes, survival, reproduction, and recruitment are needed throughout their range to inform management and conservation decisions. We collected nilgai fetuses from 3 ranches in southern Texas, including East Foundation's El Sauz and Santa Rosa ranches, and the Norias Division of the King Ranch from 2018-2021. We calculated the percentage of individuals that were pregnant in each of the sample years and overall. We determined monthly average, maximum, and minimum fetus length. Of 488 nilgai cows, we found 386 to be pregnant (79%) and 214 to be pregnant with twins (56%). We found nilgai cows as young as 1-year old to have fetuses and therefore to have reached sexual maturity. Sex ratios of fetuses during any sampling year did not differ. We found ample evidence supporting our hypothesis that nilgai are fecund on their introduced range of southern Texas. To prevent nilgai overpopulation and associated problems, harvest management strategies should be implemented, specifically on nilgai cows.

摘要

自由放养的蓝牛羚（）是一个研究较少的物种，无论是在其原产的印度、巴基斯坦和尼泊尔地区，还是在德克萨斯州南部的引入地区。在其整个分布范围内，都需要有关种群数量、生存、繁殖和补充的基础数据，以便为管理和保护决策提供依据。我们从德克萨斯州南部的3个牧场收集了蓝牛羚胎儿，包括东部基金会的埃尔绍斯牧场和圣罗莎牧场，以及金牧场的诺里亚斯分部，时间跨度为2018年至2021年。我们计算了每个样本年份以及总体中怀孕个体的百分比。我们确定了胎儿的月平均长度、最大长度和最小长度。在488头蓝牛羚母牛中，我们发现386头怀孕（79%），其中214头怀有双胞胎（56%）。我们发现年仅1岁的蓝牛羚母牛怀有胎儿，因此已经达到性成熟。在任何采样年份，胎儿的性别比例都没有差异。我们发现有充分的证据支持我们的假设，即蓝牛羚在其引入的德克萨斯州南部地区繁殖力很强。为了防止蓝牛羚数量过多及相关问题，应实施收获管理策略，特别是针对蓝牛羚母牛。