Orlu Eme E, Egbunike Gabriel N
Department of Applied and Environmental Biology, Rivers State University of Science and Technology, Nkpolu, Port Harcourt, Rivers State, Nigeria.
Pak J Biol Sci. 2010 Feb 1;13(3):120-5. doi: 10.3923/pjbs.2010.120.125.
Breed and seasonal influence on testicular morphometry, Gonadal Sperm Reserves (GSR), Extragonadal Sperm Reserves (ESR) was investigated in the barred Plymouth rock and the Nigerian indigenous breeds of the domestic fowl. Twenty sexually matured birds per breed were studied in the four seasons of the year. Breed significantly (p<0.01) influenced the body weight (2.11 +/- 0.05 vs. 1.58 +/- 0.02), paired testes weight (21.92 +/- 1.46 vs. 12.43 +/- 0.91) and all other morphometric parameters with the barred Plymouth Rock showing superiority over the Nigerian indigenous breed. The GSR, ESR and their efficiencies (GSR/g, ESR/g) were highly and significantly (p<0.01) higher in the barred Plymouth rock. Season neither significantly (P>0.05) influenced the testicular morphometric parameters, GSR, ESR nor gonadal sperm reserve/gram testis (GSR/g). The higher numerical differences observed in morphometric parameters, GSR and ESR during the early and late dry seasons suggested that the dry season favors sperm production, hence sperm reserve potentials. The testicular weight was significantly (p<0.001) correlated not only to the body weight (r = 0.63) but to paired Tunica albuginea (= 0.98, p<0.001) and paired epididymal weight (r = 0.69, p<0.001). There was also a significant (p<0.001) and positive correlation between the testicular weight and GSR (r = 0.84, p<0.001). The GSR/g (r = 0.77; p<0.001) ESR (r = 0.86; p<0.001) and ESR/g (r = 0.50, p<0.001). Based on these observations it is concluded that genetic improvement of the Nigerian indigenous breed of the domestic fowl can be carried out by increasing their body weight, hence, testicular weight through crossbreeding with the heavier barred Plymouth rock to achieve improved sperm production and reserve for year round artificial insemination.
研究了品种和季节对普利茅斯洛克鸡和尼日利亚本土家鸡睾丸形态测量、性腺精子储备（GSR）、性腺外精子储备（ESR）的影响。每个品种选取20只性成熟的鸡，在一年的四个季节进行研究。品种对体重（2.11±0.05对1.58±0.02）、双侧睾丸重量（21.92±1.46对12.43±0.91）以及所有其他形态测量参数有显著影响（p<0.01），普利茅斯洛克鸡在这些方面优于尼日利亚本土品种。普利茅斯洛克鸡的GSR、ESR及其效率（GSR/g、ESR/g）显著更高（p<0.01）。季节对睾丸形态测量参数、GSR、ESR以及性腺精子储备/克睾丸（GSR/g）均无显著影响（P>0.05）。在旱季早期和晚期，形态测量参数、GSR和ESR出现的较高数值差异表明，旱季有利于精子生成，进而有利于精子储备潜力。睾丸重量不仅与体重显著相关（p<0.001，r = 0.63），还与双侧白膜重量显著相关（r = 0.98，p<0.001）以及双侧附睾重量显著相关（r = 0.69，p<0.001）。睾丸重量与GSR之间也存在显著的正相关（p<0.001，r =0.84）。GSR/g（r = 0.77；p<0.001）、ESR（r = 0.86；p<0.001）和ESR/g（r = 0.50，p<0.001）。基于这些观察结果得出结论，通过与体型较大的普利茅斯洛克鸡杂交来增加尼日利亚本土家鸡的体重，进而增加睾丸重量，可实现遗传改良，从而提高精子生成和储备能力，以用于全年的人工授精。
