Makeri Harold Kuta, Ayo Joseph Olusegun, Aluwong Tagang, Minka Ndazo Salka
Department of Animal Health and Husbandry, College of Agriculture and Animal Science, Division of Agricultural Colleges, Ahmadu Bello University, Mando-Kaduna, NG.
Department of Physiology, Faculty of Veterinary Medicine, Ahmadu Bello University, Zaria, NG.
J Circadian Rhythms. 2017 Aug 10;15:5. doi: 10.5334/jcr.151.
Several studies carried out on humans and other mammals show that the temporal organisation of haematological parameters in the blood exhibit daily rhythms; however, such studies have been rare in poultry reared under a natural photoperiod. The present study investigated the occurrence of daily rhythms in blood parameters of broiler chickens kept under tropical climatic conditions. Ten 6-7-week-old broiler chickens served as subjects of the study. They were kept in standard individual cages under natural light-dark cycle and given access to feed and water . Two milliliters of blood was collected from each bird via intravenous cannulae inserted into the wing vein. The blood samples were collected every 4 h over a 24-h period, starting from 09:00 h on the first day and completed at 09:00 h on the second day. The blood samples were analysed for erythrocyte, total and differential leucocyte counts. A trigonometric statistical model according to the single cosinor procedure was used to describe the periodic parameters and their acrophases, and ANOVA was used to determine significant differences. The results demonstrated the existence of daily rhythms in packed cell volume, haemoglobin, white blood cell, red blood cell, heterophil, lymphocyte, eosinophil and monocyte counts, while total protein displayed no rhythm. The characteristics of the haematological parameters showed that the acrophases were restricted to the light phase of the light/dark cycle, precisely at 09:00 h, except for eosinophil and heterophil counts, which had acrophases at 21:00 h. The amplitudes of the blood parameters varied, with packed cell volume having the greatest amplitude of 4.2 ± 0.5, closely followed by lymphocyte (3.4 ± 0.5) and heterophil (2.3 ± 0.2) counts. In conclusion, the results of the study demonstrated the existence of daily rhythms with diurnal acrophases in blood parameters of broiler chickens kept under natural photoperiods and tropical conditions.
多项针对人类和其他哺乳动物开展的研究表明，血液中血液学参数的时间组织呈现出每日节律；然而，在自然光照周期下饲养的家禽中，此类研究却很少见。本研究调查了热带气候条件下饲养的肉鸡血液参数每日节律的发生情况。十只6 - 7周龄的肉鸡作为研究对象。它们被饲养在标准的个体笼中，处于自然的明暗循环下，并可自由获取饲料和水。通过插入翼静脉的静脉套管从每只鸡采集两毫升血液。在24小时内每隔4小时采集一次血样，从第一天的09:00开始，到第二天的09:00结束。对血样进行红细胞、总白细胞和分类白细胞计数分析。根据单余弦程序的三角统计模型用于描述周期参数及其峰相位，方差分析用于确定显著差异。结果表明，血细胞比容、血红蛋白、白细胞、红细胞、嗜异性粒细胞、淋巴细胞、嗜酸性粒细胞和单核细胞计数存在每日节律，而总蛋白未显示出节律。血液学参数的特征表明，除了嗜酸性粒细胞和嗜异性粒细胞计数的峰相位在21:00外，其他参数的峰相位都局限于明暗循环的光照阶段，确切地说是在09:00。血液参数的振幅各不相同，血细胞比容的振幅最大，为4.2±0.5，紧随其后的是淋巴细胞（3.4±0.5）和嗜异性粒细胞（2.3±0.2）计数。总之，本研究结果表明，在自然光照周期和热带条件下饲养的肉鸡血液参数存在具有昼夜峰相位的每日节律。
