氟中毒和碘缺乏病并发地区分布及流行病学概况

氟中毒和碘缺乏病均是世界范围内广泛存在的一类地球化学性疾病。由于两者分布范围极其广泛,在一些地区出现了氟中毒和碘缺乏病交叉流行的现象。在氟中毒和碘缺乏病并发地区,儿童智力水平显著下降,甲状腺肿发生率明显升高。氟碘关系复杂,其对脑组织和甲状腺功能的影响是广泛的,作用机理扑朔迷离。文章综述了氟中毒和碘缺乏病并发地区的分布、形成原因及儿童智力水平和甲状腺肿的流行病学调查等,为进一步研究氟碘对中枢神经系统和甲状腺损伤作用机制提供流行病学资料。     

高氟低碘对老年大鼠肺脏细胞DNA损伤的影响

研究高氟低碘对老年大鼠肺脏细胞DNA损伤的影响。健康离乳Wistar大鼠21只,随机分为4组：对照组（5只）,饲喂大鼠标准日粮,饮自来水;高氟组（5只）,饲喂大鼠对照日粮,饮100 mg/L氟化钠（NaF）去离子水;低碘组（5只）,饲喂低碘日粮（定做）,饮去离子水;高氟低碘组（6只）,饲喂低碘日粮,饮100 mg/L氟化钠（NaF）去离子水。在大鼠20月龄时,处死采取肺脏组织,检查其DNA的损伤情况。高氟组、低碘组和高氟低碘组的老年大鼠肺细胞拖尾率比对照组显著增高（P＜0.01）,高氟低碘组大鼠肺细胞拖尾率比高氟组、低碘组高,并且均有差异显著性（分别为P＜0.01和P＜0.05）;高氟组、低碘组和高氟低碘组老年大鼠肺细胞的拖尾长度比对照组显著增长,显著性差异分别为P＜0.01、P＜0.05 和P＜0.01。高氟低碘组大鼠肺细胞的拖尾长度比高氟组及低碘组增长,与低碘组有差异显著性（P＜0.01）,但与高氟组差异不显著（P＞0.05）;高氟组和高氟低碘组老年大鼠肺细胞DNA损伤主要是Ⅲ级损伤（Ⅲ级分别为70.00%和79.31%）。低碘组的肺细胞DNA损伤进入Ⅱ级和Ⅲ级范围的比较多,并且Ⅲ级占有率较高（Ⅱ级为31.25%;Ⅲ级为40.62%）。结果表明,高氟、低碘、高氟低碘都影响了大鼠肺脏细胞的DNA损伤。     

安达地区奶牛慢性氟中毒调查研究

安达地区在地理位置上处于高氟带，慢性氟中毒病流行广泛，我们以奶牛为调查对象选择临床检查疑似氟骨病牛为实验组；以哈市东北农业大学畜牧站及松花江奶牛场为对照点选择临床检查健康牛为对照组，对发病情况，临床表现进行调查并做了水氟，尿氟，水钙，血氟，血钙，血磷，血镁及羟脯氨酸含量测定，结果表明，长期饮用高氟水是导致奶牛慢性氟中毒的主要原因，水钙含量低是本病促发因素，血，尿氟值测定是诊断本病的参考指标，羟脯氨     

高碘鸡蛋及其生产开发

我国目前人群膳食中因碘的不足产生的后果令人忧虑。有关资料表明,世界上生活在碘缺乏地区的人口有10亿,其中我国就占4.25亿,除上海市外,其他省、市、自治区均有碘缺乏病流行。碘缺乏病严重威胁着人们的身体健康,特别是严重影响儿童的智力发育,消除碘缺乏病的最墓本措施是全民食盐加碘。而加入食盐中的碘为无机碘,易挥发难吸收,如碘盐存放、烹调方法不当,碘的利用率很低。鉴于这种情况,利用生物转化技术,积极开发高碘鸡蛋,投放市场,通过食物链,满足缺碘地区人民     

不同氟源对鸡新城疫疫苗免疫效果的影响

微量元素氟在动物体内具有多种生理作用 ,但它又是一种具有中等毒性的元素。摄入过量会引起中毒。在养殖业中 ,氟中毒过去多见于牛羊等大家畜 ,但是近年来随着养禽业的迅速发展 ,因高氟饲料引起的家禽氟中毒的报道屡见不鲜。众多研究表明 ,畜禽氟中毒是一种多器官受损害性疾病 ,高氟对动物的肾脏、肝脏、神经系统、内分泌系统、免疫系统、软组织等都有损害 ,而并非仅限于骨骼和牙齿[1,2 ] 。本试验采用不同氟化物人工诱发雏鸡氟中毒 ,以研究高氟对鸡新成疫 (ND)疫苗免疫效果的影响。为探讨氟中毒对家禽免疫机制的影响提供科学依据。1　材料…     

家兔氟中毒的血液学及病理学变化观察

氟是动物机体必需的微量元素之一,但氟又是中等毒性的元素,若牧草、土壤和饮水以及环境中氟含量过高可引起人和动物的中毒。氟中毒在世界范围内广泛存在,西藏也属高氟地区,例如西藏那曲,     

家畜碘缺乏病的防治

由碘缺乏引起的疾病叫碘缺乏病 ,也叫甲状腺肿大。1　病因主要原因是地球生物化学环境异常造成土壤和家畜饲料、饮水中碘不足 ,或因消化系统患病影响机体对碘的吸收 ,碘量消耗过多 ,碘在消化道被破坏等 ,都能引起本病。饲料中钙含量过多 ,饲料和饮水被细菌污染或长期摄入含生氰糖苷的饲料 (如亚麻子粉等 )均可引起碘的缺乏。碘缺乏的孕畜 ,常会导致胎儿也发生碘缺乏症。沙漠地区、灰化土及沼泽地区、水质过软或过硬的地区也常发生本病。饲养管理不良、中毒、传染病、寄生虫病 ,也容易产生碘缺乏病 ,特别是舍饲期以及泌乳的母畜更容易患病。2…     

开发单体微量元素食疗鸡蛋生产的前景

一、现实意义 单体微量元素食疗鸡蛋系指含碘、硒、锌、铁量高的鸡蛋,这些元素在人体内虽然含量甚微,却作用甚大。在促进人体生长发育、提高智力、延缓衰老和防治疾病过程中发挥着极其重要和极其特殊作用。但是,我国部分人群膳食中因摄碘、摄硒、摄锌、摄铁不足而产生的后果,令人忧虑。 据有关资料表明,我国人群因摄碘不足,每年出生数百万弱智、痴呆傻婴儿。1993年3月5日,国际碘缺乏病理事会执行主席赫特泽教授在北京召开专题研讨会指出:“中国是受碘缺乏病威胁较严重的国家,全世界有10亿人口生活在碘缺乏病地区,其中有4亿人口在中国,除上海市外,其他省市区均有碘缺乏病流行,这个     

药物防治动物氟中毒的研究

<正> 氟中毒是全世界广泛存在的一种人畜慢性中毒病,据报道,我国除上海市没有氟中毒外,其它各省市、自治区均不同程度存在本病,有的地区,氟中毒给畜牧业造成了毁灭性打击,因此如何采取有效措施来防止或延缓本病的发生具有十分重要的现实意义。由于氟中毒是长期从环境中摄入过量氟所致,因此解决本病的根本措施是将过量氟阻止在体外,然而限于地理,技术及财力等方面的因素,在全世界大面积氟病流行地区,仍需要采取一些辅助措施来减少氟在消化道吸收或促进其从尿中排出或改变氟的生物活性使其毒性减弱以及通过纠正氟产生的某些副作用或通过改善机体的整体机能达到减轻症状或延缓其发生之目的。下面就有关氟的拮抗剂或有缓减氟中毒作用的一些药物研究复习一下,供同行参考。     

黑龙江省五常某镇黄牛碘、硒缺乏检测报告

在全球人类及动物生存的环境中，普遍存在某种或多种微量元素缺乏与过剩的现象。前人的工作多集中在单个元素的详细阐述，对多种元素的相关关系研究较少，因而，人畜共存的环境中的元素问题仍然没有得到圆满解释，乃至微量元素的防治不尽人意。我国是严重的缺碘、缺硒和高氟国家，在低碘地带上有关人的碘缺乏病，试验动物模型已有较深的研究，有些地区病情已得到控制，然而在动物医学方面的碘硒缺乏病报道不多见。为此，对五常县某镇黄牛碘、硒缺乏进行了调查，现报告如下。１　材料与方法实验组随机选取黑龙江省五常市某镇农家饲养的黄牛１…     

Inherited goitre in sheep

Inherited goitre in a flock of sheep possessing a proportion of Polled Dorset blood is reported and discussed. The cases en-countered were not induced by a simple deficiency of iodine, or the presence of goitrogenic substances in their feed. Further work is recommended on the nature of the defect and its method of inheritance.     

Epidemiology and diagnosis of subclinical iodine deficiency in crossbred cattle of Punjab.

OBJECTIVE: To determine the prevalence of iodine deficiency in crossbred cows (taurus x indicus) of Punjab and to assess the diagnostic value of the plasma concentrations of thyroid hormones, total cholesterol and free fatty acids in iodine deficiency. The efficacy of ethiodised oil, as a long-term supplement of iodine, was also evaluated. PROCEDURES: Base-line survey of iodine status was conducted by measuring plasma inorganic iodine (PII) concentration in 48 crossbred cows from 31 dairy units. Concentrations of plasma triiodothyronine (T3), thyroxine (T4), total cholesterol and free fatty acids were compared between iodine deficient and normal cows. Circulating T4 and T3 concentrations were also determined before and after injection of ethiodised oil in cows with low PII levels. RESULTS: The mean prevalence of iodine deficiency was 35.9% and showed considerable geographical variation from 0 to 86% within Punjab. Cardinal clinical signs of iodine deficiency were absent and basal plasma T3 and T4 concentrations and their ratio did not differ between deficient and control cows. Activity of circulating T4 and T4:T3 ratio increased in response to ethiodised oil injection and persisted beyond 70 days after injection. CONCLUSION: Asymptomatic iodine deficiency is prevalent in crossbred cows of Punjab and response to iodine supplementation is the most reliable index of thyroid dysfunction associated with iodine deprivation. The results of this study also support the view that injection of 1 mL of 78% ethiodised oil can prevent iodine deficiency for more than 70 days.     

Iodine deficiency in cattle: compensatory changes in thyroidal selenoenzymes

The trace elements selenium and iodine are both essential for normal thyroid hormone metabolism. To investigate the relationships between these functions, heifers were maintained on iodine-deficient or iodine-sufficient diets from mid pregnancy to term. In these heifers and their offspring the interrelationship between iodine and selenium was apparent with the preferential 10- to 12-fold induction of the selenoenzyme, thyroidal type I, selenium-containing iodothyronine deiodinase activity by iodine deficiency. This was accompanied by two- to four-fold increases in cytosolic glutathione peroxidase activity, probably reflecting increased oxidative activity and metabolism in the thyroid gland in response to iodine deficiency. The above selenoenzyme activities were not affected in liver, kidney, pituitary and brain by iodine deficiency. The results are consistent with a critical role for selenium in both the normal function of cattle thyroid and key enzymes to compensate for the effects of iodine deficiency.     

硒和碘营养对蛋鸡不同组织抗氧化酶活性的影响

本试验旨在探讨饲粮中添加不同剂量的硒和碘对蛋鸡心脏、肝脏、脾脏和甲状腺中几种抗氧化酶活性的影响。288只33周龄的新罗曼蛋鸡,饲喂添加不同剂量硒和碘(0,0;0.2,0:0,0.2:0.2,0.2mgkg)的日粮12周,试验结果如下:硒缺乏时,心脏和肝脏中的GSHPx活性下降(P=0.073);碘缺乏时,心脏和肝脏中的CAT活性下降(P=0.055,P=0.097),肝脏中的GSHPx活性降低(P=0.093);硒碘互作对心脏(P<0.01)和肝脏(P<0.05)中的TSOD和CAT活性影响显著,对脾脏中的TSOD(CAT+GSHPx)值影响极显著(P<0.01)。结果表明:碘能够影响肝脏中含硒酶的活性,硒碘的互作能够影响心脏、肝脏和脾脏的抗氧化酶活性。     

The effects of iodine deficiency on ewe fertility and perinatal lamb mortality

AIMS: To substantiate a previous report of improved fertility and perinatal lamb mortality rate following iodine supplementation in a Manawatu Romney ewe flock. To contribute data which might be used to predict a response to iodine supplementation. METHODS: A controlled iodine supplementation trial was performed over 2 successive years. The possible confounding factor of different lambing paddocks on perinatal lamb mortality was removed by the reversal of the paddocks used by the supplemented and control ewes during the second year. RESULTS: During 2 successive years, iodine supplementation resulted in improved reproductive performance in a Manawatu Romney flock with 21% and 14% more lambs born to supplemented than to control mixed-age ewes in 1996 and 1997 respectively. Supplementation also resulted in improved perinatal lamb survival, although this effect was greater during the wetter 1996 Lambing season. Despite the production response during both years, a difference in lamb thyroid:bodyweight ratio was only noted following the drier 1997 winter. Ewe thyroid hormone concentrations before mating and during mid-pregnancy were poor indices of deficiency. CONCLUSIONS: Iodine deficiency should be included in the list of differential diagnoses for poor reproductive performance in ewes and in the investigation of high perinatal lamb mortality rates. CLINICAL SIGNIFICANCE: The annual cost associated with iodine deficiency in this Manawatu Romney flock is conservatively estimated at dollar 6.00 per ewe. This economic loss is considerably greater than the annual cost of iodine supplementation using iodised oil.     

氟化物对FRTL细胞甲状腺激素代谢相关基因表达的影响

为探讨氟对FRTL细胞甲状腺球蛋白(TG),甲状腺过氧化物酶(TPO)和钠碘转运体(NIS)基因表达的影响,传代培养FRTL细胞,在对数生长期用氟化钠处理,使培养液中的氟浓度分别为20、10、5、2.5、1.25 mg/L,同时设空白对照细胞.培养72 h后收集细胞;采用半定量RT-PCR分析FRTL细胞TG、TPO、NIS mRNA和β-actin表达水平.试验结果表明,与对照细胞相比,较低浓度氟化钠处理的FRTL细胞TG基因表达量代偿性升高,随氟质量浓度增加(5.0 mg/L以上),TG表达量显著降低(P<0.05);各个浓度氟化钠处理的FRTL细胞TPO、NIS基因表达量均下降或显著下降(P<0.05).由此可知,氟化物降低了甲状腺细胞TG、TPO、NIS基因表达水平,造成甲状腺摄取和利用碘、甲状腺激素合成、贮存、分泌功能障碍,进而导致甲状腺结构和功能异常.     

A practical approach to managing the risks of iodine deficiency in flocks using thyroid - weight: birthweight ratios of lambs

AIM: To establish a protocol for determining the iodine status of a flock and managing the risks of iodine deficiency, using thyroid-weight:birthweight ratios of newborn lambs and serum iodine concentrations of ewes. METHODS: Data were collected from iodine supplementation studies in Southland and Rangitikei, of sheep fed exclusively pasture or pasture plus brassica during the latter half of gestation (n=350, or 89 per treatment group). The ewes were supplemented pre-mating or at the time of pregnancy scanning with an injection of long-acting iodised oil. Serum iodine concentrations were measured in ewes prepartum in Rangitikei and postpartum at both locations. The thyroid-weight:birthweight ratios (as g/ kg) in 229 newborn lambs were determined at post-mortem examination and compared between iodine supplemented vs unsupplemented flocks using probit analysis. Samples of pasture and kale were analysed monthly for determination of iodine and selenium. RESULTS: Initial mean serum iodine concentration of all ewes was 41 mug iodine/L. Supplementation increased serum iodine concentrations regardless of forage fed, and concentrations remained high for between 127 and 206 days. The range of thyroid-weight:birthweight ratios in lambs from supplemented ewes was 0.09-0.70 (mean 0.35, standard deviation (SD) 0.147) g/kg. Among lambs from unsupplemented ewes, the range was much wider (0.21-8.5; mean 1.61, SD 1.95 g/kg). About half of those ratios were >0.8 g/kg and clearly indicative of goitre, including 62% from the groups on brassica and 18% from the Rangitikei group fed exclusively pasture. Probit calculations showed that a ratio of 0.40 (95% confidence interval (CI)=0.29-0.47) g/kg predicted with 35% probability, and a ratio of 0.80 (95% CI=0.70-0.99) g/kg predicted with 90% probability that a lamb came from an unsupplemented flock. CONCLUSIONS: Compared to iodine concentrations in forages, thyroid-weight:birthweight ratios more accurately reflected the iodine status of the flock and could be used to identify which flocks to supplement the following year. Serum iodine concentrations of ewes measured before or after lambing did not reflect forage fed, but values near 40 mug/L were associated with goitrous lambs. CLINICAL RELEVANCE: Thyroid-weight:birthweight ratios >0.8 g/kg were indicative of iodine deficiency, and ewes should be supplemented pre-mating or during pregnancy to prevent goitre the following year. Ratios <0.4 g/kg rarely occurred among deficient flocks, so the probability of benefit from supplementation was low. Intermediate ratios were ambiguous, and the iodine status of the flock could not be determined from biomarkers. In such cases individual-farm supplementation trials might be required to detect and manage the risks of marginal deficiency.     

Epidemiological and pathological studies on congenital diffuse hyperplastic goiter in calves.

Perinatal diseases such as weak calf, stillbirth, or abortion were found in 86 calves from about 600 cows in a farm (A Farm) in 1987 and 1988. Such perinatal diseases were decreased to 36 calves in 1989 and 1990 after an additional supply of seaweed was made to the maternal feeds. From these cases, 23 stillborn and weak calves were pathologically examined. The mean weight with standard deviation of the 18 thyroid glands was 36.3 +/- 28.6 g before feeding of the seaweed supplement, and 12 (67%) of the glands showed moderate to marked degree of diffuse hyperplastic goiter in histological criteria. On the other hand, 5 glands weighed 12.0 +/- 3.4 g and revealed no such histological lesions after the additional supply. These results suggest that the goiter had been associated with birth of weak calves. Further study was performed on 37 newborn calves affected with Akabane disease in 1986 in A Farm and the neighbouring B Farm located. Seven (54%) of 13 thyroid glands from A Farm and 1 (4%) of 24 glands from B Farm showed histologically moderate to marked goitrous lesions. There were dotted "Inugarashi", Rorippa indica, family Cruciferae in both pastures. The mean iodine contents of the orchard grasses were 87 and 121 micrograms/kg on dry basis in A and B Farms. Marginal deficiency or lower limit of iodine and possible thiocyanate content of "Inugarashi" may have been responsible for the goiter in the farms.     

A practical approach to managing the risks of iodine deficiency in flocks using thyroid-weight:birthweight ratios of lambs

AIM: To establish a protocol for determining the iodine status of a flock and managing the risks of iodine deficiency, using thyroid-weight:birthweight ratios of newborn lambs and serum iodine concentrations of ewes.

METHODS: Data were collected from iodine supplementation studies in Southland and Rangitikei, of sheep fed exclusively pasture or pasture plus brassica during the latter half of gestation (n=350, or 89 per treatment group). The ewes were supplemented pre-mating or at the time of pregnancy scanning with an injection of long-acting iodised oil. Serum iodine concentrations were measured in ewes prepartum in Rangitikei and postpartum at both locations. The thyroid-weight:birthweight ratios (as g/kg) in 229 newborn lambs were determined at post-mortem examination and compared between iodine supplemented vs unsupplemented flocks using probit analysis. Samples of pasture and kale were analysed monthly for determination of iodine and selenium.

RESULTS: Initial mean serum iodine concentration of all ewes was 41 µg iodine/L. Supplementation increased serum iodine concentrations regardless of forage fed, and concentrations remained high for between 127 and 206 days. The range of thyroid-weight:birthweight ratios in lambs from supplemented ewes was 0.09–0.70 (mean 0.35, standard deviation (SD) 0.147) g/kg. Among lambs from unsupplemented ewes, the range was much wider (0.21–8.5; mean 1.61, SD 1.95 g/kg). About half of those ratios were >0.8 g/kg and clearly indicative of goitre, including 62% from the groups on brassica and 18% from the Rangitikei group fed exclusively pasture. Probit calculations showed that a ratio of 0.40 (95% confidence interval (CI)=0.29–0.47) g/kg predicted with 35% probability, and a ratio of 0.80 (95% CI=0.70–0.99) g/kg predicted with 90% probability that a lamb came from an unsupplemented flock.

CONCLUSIONS: Compared to iodine concentrations in forages, thyroid-weight:birthweight ratios more accurately reflected the iodine status of the flock and could be used to identify which flocks to supplement the following year. Serum iodine concentrations of ewes measured before or after lambing did not reflect forage fed, but values near 40 µg/L were associated with goitrous lambs.

CLINICAL RELEVANCE: Thyroid-weight:birthweight ratios >0.8 g/kg were indicative of iodine deficiency, and ewes should be supplemented pre-mating or during pregnancy to prevent goitre the following year. Ratios <0.4 g/kg rarely occurred among deficient flocks, so the probability of benefit from supplementation was low. Intermediate ratios were ambiguous, and the iodine status of the flock could not be determined from biomarkers. In such cases individual-farm supplementation trials might be required to detect and manage the risks of marginal deficiency.