How Can Fluorosis in Animals be Diagnosed and Prevented?

Editorial

Austin J Vet Sci & Anim Husb. 2022; 9(3): 1096.

How Can Fluorosis in Animals be Diagnosed and Prevented?

Choubisa SL*

Department of Advanced Science and Technology, NIMS University Rajasthan, India

*Corresponding author: Choubisa SL, Department of Advanced Science and Technology, National Institute of Medical Science and Research, NIMS University Rajasthan, Jaipur, Rajasthan 303121, India

Received: August 03, 2022; Accepted: August 19, 2022; Published: August 26, 2022

Abstract

Prolonged fluoride (F) exposure in domestic and wild mammalian animals either through fluoridated drinking water or/and industrial F pollution or airborne F emission causes a serious F poisoning in the form of fluorosis disease. This dreaded disease is a worldwide health problem in both man and animals and endemic in several countries. Thousands of domesticated animals (bovines, flocks, equines, camels, etc.) in the world are suffering with fluorosis due to drinking of water having F >1.0 or 1.5 mg/L and chronic exposure to industrial F emission. In this disease, mainly in the teeth and bones, many types of permanent and irreversible deformities develop one after the other, which are very painful and dangerous for the animal health. But this disease also affects other parts or soft organs of the animal body. F-induced toxic effects or anomalies in teeth, bones, and soft organs are generally referred as dental, skeletal, and non-skeletal fluorosis, respectively. Nevertheless, skeletal fluorosis is most dangerous in animals, due to which animals become victims of lameness at an early age. Fluorosis can be easily diagnosed when it is an advanced stage, but it is a bit difficult to diagnose when it is in its early stages. Nevertheless, on the basis of appearance of its main clinical or pathognomonic signs and careful physical examination, the presence of this disease in the animal can be confirmed or diagnosed. In present editorial, for researchers and investigators, some helpful and important parameters for the diagnosis of fluorosis in domesticated animals such as history, diverse clinical or pathognomonic signs, and the testing of biological samples, blood serum and urine for evidence of F have been highlighted. Simultaneously, different possible or feasible ways for the mitigation or prevention of chronic F poisoning in domestic animals have also been discussed. Along with this, those simple measures how to save animals from getting fluorosis have also been described well in this editorial.

Keywords: Animals; Bio-indicators; Bio-markers; Dental fluorosis; Diagnosis; Drinking water; Fluoride; Humans; Industrial fluoride pollution; Nonskeletal fluorosis; Prevention; Skeletal fluorosis

Introduction

Fluoride (F) is found naturally in water, air, and soil in varying amounts [1]. In groundwater it occurs due to weathering and leaching of F-bearing minerals from rocks and sediments [2]. Airborn F emission or industrial F pollution also contaminates the surface water, soil, environment, vegetation, agriculture crops, and food chains and webs [3]. Though F is not an essential element for growth and development and for most organisms in the environment [4] and is also an undesirable substance in animal feed [5]. However, it has vital role or contribution in strengthening and mineralization of teeth and dental enamel. In some animals, F is considered to be an essential element, as diets low in F impaired fertility and development [5]. When F is ingested in a small quantities then it becomes beneficial for dental health by reducing the dental caries, whereas higher concentrations, >1.0 or 1.5 mg/L or ppm [1] may cause fluorosis in both humans [6-12] and diverse species of domestic and wild mammalian animals [13-30].

Chronic F poisoning or fluorosis is a worldwide health problem and endemic at least in 25 countries. The principal cause of fluorosis in domesticated and wild animals is the prolonged exposure of F through fluoridated drinking water [1,26,31]. However, industrial F emission and F contaminated foods are also potential sources of F exposures for the genesis of fluorosis in animals [3,16,25]. As per guidelines of the World Health Organization (WHO) the F in the drinking water should not be higher than 1.5 mg/L [1]. Above this limit, it becomes toxic and injurious for health and causes permanent and irreversible different forms of teeth and bones deformities. Based on occurring of F induced changes in hard and soft organs, fluorosis has been categorised into three forms: (i) dental fluorosis, (ii) skeletal fluorosis, and (iii) non-skeletal fluorosis. All three forms may occur in the same animal. The diagnosis of fluorosis in animals could be done on the basis of history, clinical or pathognomonic signs, and testing of biological samples, blood serum and urine for evidence of F. Animals can be saved from the ill effects of fluorosis. For this it is important that F has to be prevented from entering the body of animals under any circumstances. For this it is necessary to provide F free water and food to the animals. The effect of F can also be prevented to a great extent by giving nutritious food to domesticated animals. General awakening in animal keepers and collective efforts are also important and highly needed in the prevention of fluorosis in animals. Present editorial will be useful for researchers and investigators in the diagnosis and prevention of fluorosis in domestic animals.

Once F enters the body it is absorbed by the digestive and/or respiratory systems. Then absorbed F finally reaches to each part of the body through blood circulation. More than 50% absorbed F is excreted in the form of stool, urine, and perspiration, while rest is retained in the body where it accumulates in diverse organs. However, its maximum accumulation is found in the calcified organs, bones and teeth compared to non-calcified soft organs. Nevertheless, the bio-accumulation of F in growing calves and juvenile animals is relatively higher than adult animals [5]. Hence, calves and juveniles generally revealed an earlier signs of chronic F poisoning that is dental fluorosis [28].

The bio-accumulation of F causes interference in various physiological and metabolic processes and then ultimately triggers the genesis of adverse reversible and non-reversible health effects or pathological changes. These F-induced health effects are collectively known as fluorosis [1]. Various F-induced pathological changes in both teeth and bones are permanent, irreversible and untreatable and can be easily identified visually, whereas in soft tissues or organs these health effects are generally reversible and disappeared after the removal or check the F exposure. Nevertheless, the prevalence and severity of fluorosis in animals is much more depend on the concentration of F in drinking water and its duration or frequency of F exposure, density of bio-accumulation of F, food nutrients, chemical constituents of drinking water, species, age, environmental factors, individual F susceptibility or tolerance, genetics, etc. [32-37].

Dental Fluorosis

The earliest and most recognizable clinical sign of chronic F poisoning is dental defragmentation or mottling (dental fluorosis) which could be seen by necked eyes. In fact, dental fluorosis is sensitive, indexive, and rampant in the F endemic areas. Dental fluorosis in animals such as cattle (Bos taurus), water buffaloes (Bubalus bubalis), camels (Camelus dromedarius), sheep (Ovis aries), goats (Capra hircus), horses (Equus caballus), donkeys (Equus asinus), etc., is generally, characterised with bilateral, striated, and horizontal compact streaks stained with light to deep brownish in colour on enamel of teeth [18-26]. In general, these pigmented or stained streaks are more contrast, regular, condensed, and sharply visualized on anterior teeth (incisors) in calves and juveniles or immature animals as compared to old animals (Figures 1-10). In some cases, dental fluorosis is also appeared in the form of white or light to deep brownish spots, patches, and fine dots or granules on the enamel of teeth. In severe dental fluorosis, pronounced loss of the tooth-supporting alveolar bone occurs with recession and swelling of the gingival tissues and excessive abrasion or irregular wearing of the teeth (Figures 4, 8 and 10).

Citation: Choubisa SL. How Can Fluorosis in Animals be Diagnosed and Prevented?. Austin J Vet Sci & Anim Husb. 2022; 9(3): 1096.