唾液酸和糖胺多糖在鸡慢性氟中毒早期诊断中的意义

Significance of sialic acid and glycosarninoglycan in early diagnosis of chronic fluorosis in chick

为探讨唾液酸（ＳＡ） 、糖胺多糖（ ＧＡＧ） 在鸡慢性氟中毒早期诊断中的意义，以期筛选出诊断慢性氟中毒早期的敏感指标，选用２５０ 只１ 日龄罗曼蛋鸡，随机分为５ 组，每组５０ 只，饲喂相同的全价日粮。Ⅰ组为正常对照组，Ⅱ～Ⅴ组在日粮中添加不同水平的氟化钠，使日粮中氟含量分别为５００ 、１０００ 、１５００ 和２０００ ｍ ｇ／ｋｇ ，试验期为１５０ ｄ ，每隔３０ ｄ 采集血样１次，测定血清中氟、ＳＡ、ＧＡＧ 的含量，观察试验鸡的临床表现。结果，试验成功地复制出不同程度的鸡慢性氟中毒模型；饲料中所加氟量与血清中氟含量呈明显的剂量效应关系；氟中毒组鸡血清中ＳＡ 含量均低于对照组，而血清中ＧＡＧ 含量则均高于对照组；血清中氟含量与ＳＡ 含量呈显著的负相关（ｒ ＝ － ０ ．７７３ ， Ｐ＜ ０ ．０１） ， 与ＧＡＧ 含量则呈显著的正相关（ｒ ＝ ０ ．７９８ ，Ｐ＜ ０ ．０１） ；各中毒组ＳＡ／ ＧＡＧ 值与正常值相比降低３０ ％ 以上。由此可见，氟中毒可明显影响机体内ＳＡ、ＧＡＧ的代谢，血清中ＳＡ、ＧＡＧ 含量的变化可灵敏地反映氟对机体的损伤情况。可将ＳＡ／ ＧＡＧ 值降低３０ ％ 或更多作为鸡慢性氟中毒的敏感、可靠的早期诊断指标。

In order to study the signifiance of changes of sialic acid (SA) and glycosaminoglycan (GAG) in sera from chicks with chronic fluorosis for early diagnosis of chick fluorosis and to select the sensitive index for diagnosing chronic fluorosis, 250 one day old Roman chicks were randomly divided in to 5 groups, each 50, which were fed whole valent diet. The group I was served as contrd and the other four groups (the group Ⅱ、Ⅲ、Ⅳ、Ⅴ) were fed the diets containing 500, 1000, 1500 and 2000 mg/kg fluorine as sodium fluorine, respectively, for 150 days. The serum specimens were sampled from the chicks every other 30 days for measuring the contents of serum flworine, SA and GAG and the clinic signs of the tested chicks were observed in the test period. The results showed as follows: The animal models of chick chronic fluorosis were successfully established; Serum F concentration presented an obvious dose effet regular rule; Compared with the control group, the serum SA content in all fluorosed groups decreased, whereas the GAG level Increased. The content of serum Fsignificantly correlated with the contents of serum SA and GAG and the correlative coefficients were r=-0.773 and r=0.798, respeetively. P<0.01 and P<0.01,The SA/GAG rates in all fluorosed groups falled a 30% or more than that of the control. IU was proved that fluorine was able to change the SA and GAG metabolism in chicks and the changes of serum SA and GAG levels were able to present the lesion state of chicks caused with fluorosis. It appears that the ratio of SA/GAG reducing 30% or more in sera of fluorosed chicks can be used as a more sensitive, more reliable and early inden for diagnosing chick fluorosis.