Blood parameters and hepatic histopathology of broilers fed rations supplemented with essential oils

ABSTRACT This study aimed to evaluate the hematological profile, hepatic function, and histopathology of mixed-sex broilers fed rations supplemented with microencapsulated essential oils from Cymbopogon flexuosus (lemon grass) and Lippia rotundifolia (chá-de-pedestre). One hundred and fifty Cobb chicks were housed in cages from 1 to 42 days of age in a completely randomized design, with six replicates with five chickens in each of five treatments (150 total chicks): basal diet without antibiotic growth promoter (negative control), diet with enramicina and salinomycin (positive control), diet with lemon grass essential oil, diet with L. rotundifolia essential oil, and diet with a mixture of lemon grass and L. rotundifolia essential oils. Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were significantly lower in untreated broilers (negative control group). Gender was not associated with erythrogram values, but aspartate aminotransferase activity (AST) was higher in females. Gamma-glutamyl transferase (GGT) was higher in chicks in the group that received rations with lemon grass oil. Broilers that received L. rotundifolia oil developed more hepatic lesions, although no effect of sex was observed related to the lesion score. Biliary hyperplasia and fibroplasias were observed in all groups, with higher histopathology scores in broilers that received diets containing L. rotundifolia oil. Mixed-sex broilers fed rations supplemented with lemon grass and L. rotundifolia essential oils have normal complete blood counts and unspecific hepatic lesions and are characterized by lipidosis, hyperplasia of the bile ducts, and fibroplasia.

摘要
本研究旨在评估饲喂添加了微囊化弯曲香茅（Cymbopogon flexuosus，柠檬草）与圆叶过江藤（Lippia rotundifolia，平地茶）精油的日粮后，混合性别肉鸡的血液学指标谱、肝功能及组织病理学变化。本试验选取150羽科宝肉鸡雏鸡，采用完全随机设计，于1~42日龄笼养，设置5个处理组，每组设6个重复，每个重复5羽鸡（总鸡数150羽）：不含抗生素生长促进剂的基础日粮组（阴性对照组）、添加恩拉霉素与沙利霉素的日粮组（阳性对照组）、添加柠檬草精油的日粮组、添加圆叶过江藤精油的日粮组，以及添加柠檬草与圆叶过江藤混合精油的日粮组。
结果显示，阴性对照组（未添加抗生素生长促进剂组）肉鸡的平均红细胞体积（mean corpuscular volume, MCV）与平均红细胞血红蛋白含量（mean corpuscular hemoglobin, MCH）显著降低。性别与红细胞各项参数无显著关联，但雌性肉鸡的天冬氨酸氨基转移酶（aspartate aminotransferase, AST）活性更高。饲喂柠檬草精油日粮组的肉鸡γ-谷氨酰转移酶（gamma-glutamyl transferase, GGT）活性升高。饲喂圆叶过江藤精油的肉鸡肝脏病变程度更严重，尽管未观察到性别对病变评分存在影响。所有组别均可见胆管增生与纤维组织增生，其中饲喂含圆叶过江藤精油日粮的肉鸡组织病理学评分更高。
饲喂添加柠檬草与圆叶过江藤精油日粮的混合性别肉鸡，其全血细胞计数指标均处于正常范围，仅出现非特异性肝脏病变，病理特征为肝脂质沉积、胆管增生及纤维组织增生。