飼糧添加黃耆、淫羊藿及補骨脂對蛋雞產蛋性狀與免疫反應之影響

Abstract

本研究旨在探討飼糧中添加不同劑量之三種中草藥（即黃耆、淫羊藿、補骨脂）對蛋雞產蛋性狀與免疫反應之影響。供試動物為100隻單冠白色來航蛋雞（海蘭W-36品系）；於雞隻18週齡時，將其逢機分配至十個飼糧處理組：(1) 對照組（基礎飼糧，不含中草藥）；(2-4) 添加黃耆5、15及30 g/kg組；(5-7) 添加淫羊藿5、15及30 g/kg組；(8-10) 添加補骨脂5、15及30 g/kg組。試驗期自18至80週齡，分為產前（育成）期（18∼20週齡）及產蛋期（21∼80週齡）；產蛋期又細分為Phase I（21∼31週齡）、Phase II（32∼44週齡）、Phase III（45∼60週齡）及Phase IV（61∼80週齡）四階段。產蛋期期間，記錄雞隻產蛋數，以計算隻日產蛋率；測定蛋重、平均採食量，以計算隻日產蛋量及飼料轉換率；亦測定蛋殼強度、蛋黃色度、雞蛋豪氏單位三項蛋品質指標。於雞隻41週齡及75週齡時，接種新城雞病（ND）疫苗，並於接種前後分別採血，測定血清中免疫球蛋白（包括IgG、IgM及IgA）之濃度與抗ND病毒 （NDV）抗體之力價。另於雞隻80週齡（即試驗結束）時採血，並測定血清轉胺酶ALT與AST之活性，以及血清尿酸之含量。結果顯示，無論在Phase I∼III任一階段內，飼糧中添加5、15或30 g/kg之黃耆、淫羊藿或補骨脂，對蛋雞之隻日產蛋率、蛋重、平均採食量、隻日產蛋量及飼料轉換率，皆無顯著影響（P > 0.05）。而在Phase IV階段內，飼糧中添加5或30 g/kg黃耆及5、15或30 g/kg補骨脂，雖對蛋重、平均採食量無顯著影響（P > 0.05），但可顯著改善蛋雞之隻日產蛋率、隻日產蛋量及飼料轉換率（P < 0.05）。蛋品質方面，在Phase I∼IV四階段內，飼糧中添加5、15或30 g/kg之黃耆、淫羊藿或補骨脂，對雞隻蛋殼強度、蛋黃色度及雞蛋豪氏單位，皆無顯著影響（P > 0.05）。雞隻41週齡及 75週齡時，其血清免疫球蛋白濃度，不受飼糧中添加5、15或30 g/kg之黃耆、淫羊藿或補骨脂所影響（P > 0.05）。而41∼44週齡期間，飼糧中無論添加5、15或30 g/kg之黃耆、淫羊藿或補骨脂，皆不影響蛋雞於接種ND疫苗後血清NDV抗體之力價（P > 0.05）；然在75∼80週齡期間，飼糧中添加15或30 g/kg之黃耆及5 g/kg之補骨脂，可提升蛋雞於接種ND疫苗後血清NDV抗體之力價（P < 0.05）。此外，飼糧中添加5、15或30 g/kg之黃耆、淫羊藿或補骨脂，對蛋雞血清轉胺酶ALT與AST之活性（肝功能指標）及血清尿酸含量（腎功能指標），皆無顯著影響 （P > 0.05）。綜上所述，飼糧中添加30 g/kg之黃耆或5 g/kg之補骨脂，不僅能改善蛋雞在Phase IV階段（61∼80週齡期間）內之隻日產蛋率、隻日產蛋量及飼料轉換率等生產性狀，且能提高雞隻75∼80週齡期間之NDV抗體生成反應，故可供農民參考使用於老齡（60週齡以上）蛋雞之飼養，以延遲雞隻之淘汰時間。

The present study was conducted to evaluate the effects of dietary Chinese herbal medicine (CHM) supplementation on production performance and immune function in commercial laying hens. One hundred 18-week-old White Leghorn layers were randomly allocated to 10 dietary treatments with 10 birds each. Hens were fed diets containing three levels (5, 15 and 30 g/kg) from three commercial CHM (Astragalus membranaceus, Ast; Epimedium brevicornum, Epi; Psoralea corylifolia, Pso), in comparison to basal diets without CHM as control group, from 18 to 80 wk of age. The whole experimental period was divided into developing period (18−20 wk of age) and laying period (21−80 wk of age), and the latter was subdivided into four phases as follows: I (21−32 wk of age), II (33−44 wk of age), III (45−60 wk of age) and IV (61−80 wk of age). Egg production, egg weight, feed intake, egg quality parameters (including eggshell breaking strength, yolk color score and Haugh unit) were measured, and egg mass and feed conversion ratio (FCR) were also calculated. Serum immunoglobulin (Ig) G, M and A level as well as antibody titers against Newcastle disease virus (NDV) were determined. Activity of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and content of uric acid (UA) were measured. The results showed that egg weight and feed intake were not significantly influenced by different type or level of CHM supplementation throughout the study (P > 0.05). However, addition of Ast at a level of 5 or 30 g/kg and Pso at 5, 15 or 30 g/kg increased egg production and egg mass, as well as reduced FCR compared to the control group during Phase IV. There was no significant difference between control group and other groups for egg quality parameters measured (P > 0.05). Neither type nor level of dietary CHM had significant effect on serum IgG, IgM and IgA levels, while antibody titers against NDV were significantly higher in hens fed diets containing 15 or 30 g/kg of Ast and 5 g/kg of Pso compared to the control group after NDV vaccination (on Day 21) during 75−80 wk of age. Serum ALT and AST activity and UA content were not significantly affected by different type or level of dietary CHM at the end of the trial (80 wk of age) (P > 0.05), which suggested that long-term feeding of three levels from three commercial CHM had no adverse effects on liver and kidney function in laying hens. To sum up, dietary supplementation of Ast at a level of 30 g/kg and Pso at 5 g/kg could not only exert beneficial effects on egg production, egg mass and FCR during Phase IV (61−80 wk of age) but also increase antibody response to NDV during 75−80 wk of age. Thus, these two formulae are expected to be added in diets for old layers aged more than 60 weeks so that the hens could produce more total egg mass and prolong the timing of elimination.