Department of Animal Production and Health, School of Agriculture and Technology, University of Energy and Natural Resources, Dormaa Campus, Dormaa Ahenkro, Ghana.
Department of Animal Science, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
Trop Anim Health Prod. 2022 Jun 9;54(4):207. doi: 10.1007/s11250-022-03207-6.
High ambient temperatures pose serious productive challenges to poultry farmers in the tropics with adverse consequences such as reduced egg production. A study was undertaken to assess the effect of naked neck (Na) and frizzle (F) genes on the performance of F and F generations of crosses of commercial and indigenous chickens in Ghana. One thousand, five hundred and sixty-five (1,565) eggs distributed in a randomized complete block design comprising 4 genotypes and 15 hatches were used for the first study. The eggs were produced from 33 each F crossbred normal-feathered (nanaff), naked neck (Na), frizzle (F) and both (Na and F) alleles carrying chickens to determine the effects of these genes on fertility and hatchability. Data were analysed using the mixed model procedure of GenStat statistical software. Eggs from birds with the heat-tolerant genes, either in the single or double doses, were significantly more fertile than those from birds without the genes. Eggs of birds carrying the F allele had significantly (P < 0.05) higher hatchability than eggs from birds carrying the Na allele.Subsequently, 199 F crossbred chickens obtained from six hatches generated by the F generation were used for the evaluation of growth, egg production, haematological and blood biochemical parameters. The genotypic groups were normal feathered (nanaff), homozygous naked neck (NaNaff), heterozygous naked neck (Nanaff), homozygous frizzle (nanaFF), heterozygous frizzle (nanaFf), double homozygous naked neck-frizzle (NaNaFF) and double heterozygous naked neck- frizzle (NanaFf). The Nanaff recorded a significantly (P < 0.05) heavier day-old body weight compared to all other genotypes except the NaNaff birds.The nanaff genotype reached sexual maturity significantly earlier than all other genotypes. Hen day egg production and egg weight were also significantly higher in nanaff birds compared to birds carrying either Na or F allele, or both alleles. All birds carrying the naked neck and frizzle genes had significantly higher packed cell volume (PCV) concentration than the nanaff genotype. The Nanaff genotype recorded a significantly higher blood haemoglobin concentration compared to the nanaff, nanaFf and NaNaFF ones. However, birds carrying the thermoregulatory genes recorded significantly (P < 0.05) higher haemoglobin values except for the heterozygous frizzle. The thermoregulatory genes are of importance in chicken populations in Ghana as they positively influence percentage fertility of chicken eggs and PCV concentrations of chicken blood.
高温环境给热带地区的家禽养殖户带来了严重的生产挑战，导致产蛋量下降等不良后果。本研究旨在评估裸颈（Na）和卷毛（F）基因对加纳商业和本地鸡杂交 F 和 F 代的性能的影响。第一部分研究使用了 1565 个鸡蛋，这些鸡蛋分布在一个随机完全区组设计中，包括 4 种基因型和 15 个孵化批次。这些鸡蛋来自 33 只 F 代杂交鸡，包括正常羽（nanaff）、裸颈（Na）、卷毛（F）和同时携带 Na 和 F 等位基因的鸡，以确定这些基因对受精率和孵化率的影响。数据使用 GenStat 统计软件的混合模型程序进行分析。带有耐热基因的鸟类的鸡蛋，无论是单剂量还是双剂量，其受精率都明显高于没有这些基因的鸟类。携带 F 等位基因的鸡的孵化率明显（P<0.05）高于携带 Na 等位基因的鸡。随后，使用来自 F 代 6 个孵化批次的 199 只 F 代杂交鸡进行生长、产蛋、血液学和血液生化参数的评估。基因型组为正常羽（nanaff）、纯合裸颈（NaNaff）、杂合裸颈（Nanaff）、纯合卷毛（nanaFF）、杂合卷毛（nanaFf）、双纯合裸颈-卷毛（NaNaFF）和双杂合裸颈-卷毛（NanaFf）。与除了 NaNaff 鸟类之外的所有其他基因型相比，Nanaff 记录的 1 日龄体重显著更重。Nanaff 基因型达到性成熟的时间明显早于所有其他基因型。与携带 Na 或 F 等位基因或两个等位基因的鸟类相比，nanaff 鸟类的母鸡日产蛋数和蛋重也显著更高。所有携带裸颈和卷毛基因的鸟类的红细胞压积（PCV）浓度均显著高于 nanaff 基因型。与 nanaff、nanaFf 和 NaNaFF 基因型相比，Nanaff 基因型的血液血红蛋白浓度显著更高。然而，除了杂合卷毛鸡之外，携带体温调节基因的鸡的血红蛋白值明显更高。体温调节基因对加纳的鸡群很重要，因为它们可以积极影响鸡卵的受精率和鸡血液的 PCV 浓度。
