Abstract

General Background: The thyroid gland, an essential endocrine organ located in the anterior neck, regulates iodine homeostasis and secretes thyroid hormones that influence metabolism and cellular function. Specific Background: Understanding thyroid hormone physiology is crucial for veterinary students, as it impacts both human and animal health. Knowledge Gap: Limited research exists on veterinary students’ awareness of thyroid hormone physiology, particularly its effects on the body. Aims: This study assesses veterinary students’ knowledge of thyroid hormone function and provides recommendations to enhance their understanding. Methodology: A descriptive, cross-sectional, questionnaire-based study was conducted at the College of Veterinary Medicine, University of Basrah, with 150 students (86 females, 64 males). The questionnaire included demographic data and knowledge assessments on thyroid function, hypothyroidism, and hyperthyroidism. Results: Female students constituted the majority (57.33%). Most participants (94%) were aged 19–28. The results showed varying levels of knowledge, with 95% of responses being significant and a high mean score, indicating substantial understanding of thyroid hormone effects. Novelty: This study highlights veterinary students' competence in endocrinology and suggests targeted educational interventions for knowledge enhancement. Implications: Findings emphasize the need for improved curriculum design and interactive learning strategies to reinforce thyroid physiology education in veterinary programs.

Highlights:

1. Knowledge Levels: Students showed varied understanding of thyroid hormone function.
2. Significant Findings: 95% of responses were significant, indicating strong knowledge.
3. Educational Implications: Findings highlight the need for better thyroid education.

Keywords: Thyroid gland, Veterinary students, Endocrinology, Hormone physiology, Knowledge assessment

Introduction

Once thyroid hormone is activated from the prohormone thyroxine (T4) to the active form triiodothyronine (T3), it controls a large number of variables [1]. The production of several thyroid hormone receptor (TR) isoforms, cell and tissue-specific thyroid hormone transporters, and interactions with corepressors and coactivators make the signaling pathway intricate and tightly controlled [2, 3]. Additionally, thyroid signals frequently interact with a variety of other signaling pathways [4, 5]. Here, we examine how our knowledge of this route has been influenced by clinical findings and animal models, and how this knowledge may be applied to treatment strategies for a variety of ailments.

The gland's two lobes—the left and right lobes—are connected by an intermediary tissue called the isthmus. The pyramidal lobe, a third lobe, occasionally protrudes from the isthmus. It features levator glandulae thyroideae, a fibrous/fibromuscular band that extends from the hyoid body to the isthmus [6].

The external branch of the superior laryngeal nerve and the recurrent laryngeal nerve are two important nerves that are near the thyroid gland. The vagus nerve has both branches. Damage to these nerves during thyroidectomy results in breathing difficulties and/or phonation impairment. Singing becomes extremely difficult when one of the superior laryngeal nerve's branches is injured. Breathing problems and hoarseness of voice can result from unilateral damage to the recurrent laryngeal nerve. Serious bilateral recurrent laryngeal nerve damage frequently requires a tracheostomy [7].

The true and false capsules completely enclose the thyroid gland. Further down to the actual capsule, the thyroid gland is made up of a deep capillary plexus. Because of this physical configuration, removing the plexus with capsule during thyroidectomy is essential [8].

Metabolism

The basal metabolic rate is raised by thyroid hormone. Thyroid hormones promote protein anabolism and carbohydrate metabolism. High levels of thyroid hormones can also cause protein catabolism. Although thyroid hormones don't alter blood sugar levels, they can raise gluconeogenesis, glucose oxidation, glycogen synthesis, and glucose reabsorption [9].

Growth During Childhood

Thyroid hormones and growth hormone work together to promote bone growth in youngsters. It stimulates osteoblasts, osteoclasts, and chondrocytes. Through axonal growth and myelin sheath formation, thyroid hormone also aids in the maturation of the brain [10].

Anatomy and physiology

In human physiology, the thyroid gland and its primary product, thyroid hormone, are crucial. Therefore, any doctor treating patients with thyroid diseases must have a thorough understanding of the anatomy, physiology, and embryology of the thyroid gland. The thyroid gland is a shield-shaped structure in the lower neck that is situated anterior to the trachea. There is extensive research being done on the molecular biology of thyroid function. The sodium iodide symporter and the thyroid-stimulating hormone receptor are examples of clinically significant molecules that have been found and thoroughly described. Our knowledge of thyroid physiology has greatly increased as a result of these studies. Consequently, there are currently or will soon be innovative methods for diagnosing and treating thyroid diseases [11].

Pathophysiology

Hyperthyroidism: Thyroid gland disorders can cause an overabundance of T3 and T4 production in addition to a compensatory drop in TSH. Furthermore, thyrotrophic adenoma can result in elevated T3 and T4 production as well as uncontrolled TSH production. In certain cases, there is an ectopic production of thyroid hormone, which results in a decrease in TSH and an increase in thyroid hormones [12].

Hypothyroidism: TSH rises in primary hypothyroidism as a result of the thyroid gland producing fewer thyroid hormones. Pituitary abnormalities that result in decreased TSH release and low T3/T4 levels are the cause of secondary hypothyroidism. Hypothalamic problems lead to tertiary hypothyroidism, which is characterized by decreasing levels of TRH, TSH, and T3/T4 [13].

Symptoms of Hypothyroidism

Apathy, slower cognition, dry skin, baldness, elevated low-density lipoproteins, and elevated triglycerides are all symptoms of a generalized lowered basal metabolic rate. When psychiatric patients exhibit apathy and impaired cognition, hypothyroidism must be checked out. Bradycardia, constipation, and decreased sweating can result from hypothyroidism's reduction of sympathetic activity. Reduced transcription of sarcolemma genes can cause patients to exhibit myopathy and reduced cardiac output [14].

Hypothyroidism can result in hyperprolactinemia. Prolactin and TSH release are stimulated by the hypothalamus's thyrotropin-releasing hormone (TRH). The secretion of GnRH, LH, FSH, and testosterone can all be suppressed by prolactin. Breast tissue expansion is another effect of prolactin [15].

Due to a reduction in the removal of complex glycosaminoglycans and hyaluronic acids from the dermal reticular layer, patients with hypothyroidism may exhibit myxedema. The nonpitting edema is pretibial at first. Patients may experience widespread edema as their hypothyroidism worsens [16].

Symptoms of Hyperthyroidism

Increased Na+/K+-ATPase is a result of generalized hypermetabolism from hyperthyroidism, which encourages thermogenesis. Beta-adrenergic receptors are also upregulated in many organs, and catecholamine secretion is elevated. The hyperadrenergic condition causes a reduction in peripheral vascular resistance. Phospholamban, a protein that typically lowers the affinity of calcium-ATPase for calcium in the sarcoplasmic reticulum, is reduced in the heart as a result of hyperthyroidism. Decreased phospholamban causes more Ca+ to flow between the cytosol and sarcoplasmic reticulum, which increases contractility. Elevated cardiac output is also a result of enhanced beta receptors in the heart [17].

Methods

Design of the study

A descriptive cross-sectional study questionnaire-based study was carried to study the Physiological effect of thyroid hormones as viewed by the students.

Setting of the study

The study conducted in college veterinary of at the university of Basrah

Sample of study

The sample of the study is a total of 150 students (86) Female and male (64).

Data collection

The data was collected through the use of structured Questionnaire prepared by the researchers and through a direct personal interview with each male and Female student who participated in the study. The data collection was carried out from each student spends approximately (5-10) minutes to complete the interview.

The study instruments

A questionnaire of the four parts was prepared by researchers and then displayed to faculty as experts for take their opinions and advices .the questionnaire consist of four parts , the first part was about the demographic information (Age, sex, marital status, stage of study, and other) .Second part of questionnaire consist your knowledge about the thyroid gland .Third part of the questionnaire consist your knowledge about the Hypothyroidism and fourth part your knowledge about the Hyperthyroidism.

Statistical data analysis

For data analysis 1- Percentage. 2- Frequency. 3- Mean of score. used by Manual method

Results and Discussion

Result

This table showed that the percentage of males was 42.66, while the percentage of females was 57.33. Likewise, with regard to age, the first period was (19-28), their percentage was 94%, the second period was (29-38), their percentage was 4.66, and the third period was (39-48), their percentage was 1.33. As for marital status, the percentage of single people was 84%, while the percentage of married people was 16%. Likewise, the percentage of the study stage for stage 2 was 44%, the percentage of third stage 3 was 20%, and the percentage of fourth stage 4 was 36%.

The table showed the knowledge of the students about thyroid gland ,93.33% know the exact location of the thyroid. 90% know the thyroid hormones, only 64% of the students know the role of the gland in controlling energy expenditure by the body cells.70 % know the role of the gland in Iodine regulation and storage.63.33% of the students know the heat regulation function of the thyroid.64.66% accept that Iodine deficiency causes goiter. 93.33% of the students agree that neck swelling is the most obvious sign in patient with goiter.

When we examine the mean of scores for the items related to thyroid gland as shown in the table above, we found that the students had significant knowledge, where the mean of scores is more than 2.

The table showed that 72.66% of the students agree that hypothyroidism (low thyroid function) lead to decrease heart rate, only 50 % of the students know the reactive rises in the blood pressure due to hypothyroidism. 81.33% know the cold feeling, only 44.66 % agree with constipation ,74.66 % know the irregular menses in women, 68.66% know the weight gaining effect of the disease ,63.33% know that the disease causes dry skin.

When we examine the mean of scores for the items related to hypothyroidism as shown in the table above, we found that the students had significant knowledge, where the mean of scores is more than 2.

The table showed that 74.66% know that the disease cause hot feeling, 76.66% agree that the disease causes sweating, 82% accept that the disease causes insomnia and stress, 66.66% know that the disease speed up the body metabolism, and 58.66% know that the disease causes hand tremor

When we examine the mean of scores for the items related to hyperthyroidism as shown in the table above, we found that the students had significant knowledge, where the mean of scores is more than 2.

Discussion

This part divided into two parts according to the objectives of the study.

Part One: Socio- D emographic Data of the Students

According to these results showed that the percentage of the percentage of females was 57.33.

These results agreed with numerous studies [18-22] that mention the most of the study sample were females.

Regarding the age of the study sample, the highest period was between 19 and 28, their percentage was 94%.

These results agreed with numerous studies [23-26] that mention the most of the study sample were females.

Regarding the marital status, the highest percentage of single people was 84%.

These results agreed with numerous studies [27-30] that mention the most of the study sample were females.

Regarding the stage of the students, the percentage of the study stage for stage 2 was 44%.

These results agreed with numerous studies [31-34] that mention the most of the study sample were females.

Part Two: Students Knowledge Regarding t he Physiological Effects of Thyroid Hormones

According to these results the most of the students have good knowledge regarding the physiological effects of thyroid hormones.

These results agreed with numerous studies [35, 36] which mention the most of the students have good knowledge regarding the physiological effects of thyroid hormones.

From the researcher point of view, this good knowledge due to the curriculum contains the thyroid gland disorders (hypothyroidism, hyperthyroidism, goiter, physiology of the thyroid gland).

Conclusion

1-Female students made up the largest percentage in answering the evaluation questionnaire.

2-Study results show different levels in students’ knowledge about thyroid hormone.

3-95%of the answers were significant.

4-The total mean of score was significant.

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