1.0 Introduction
Providing sufficient food for Nigeria’s growing population remains a major challenge. A healthy diet rich in protein is essential to prevent malnutrition and reduce the risk of disease in a rapidly expanding population [1]. Fish represents an important and accessible source of high-quality protein, being easily digestible and rich in essential nutrients. Understanding the reproductive biology and health of fish is critical for managing populations and maximizing yield, as it provides insights into breeding cycles, fecundity, and stock sustainability [2]. The commercial potential of a fish species is closely linked to its life history, population dynamics, culture practices, and overall management strategies [3]. Among cultured species in Nigeria, African catfish (Clarias gariepinus) is the most widely farmed, owing to its adaptability to varied environmental conditions, high stocking density tolerance, rapid growth, disease resistance, acceptance of formulated feeds, high fecundity, quality meat, and ease of artificial breeding [4]. Globally, fish contributes significantly to human nutrition, providing over 1.5 billion people with nearly 20% of their animal protein intake and 3 billion people with at least 15% [5]. Detailed knowledge of reproductive biology is fundamental for assessing the commercial potential of fish stocks, guiding culture practices, and managing fisheries effectively [6]. The reproductive capacity of a population, particularly gonadal development, is a key factor in evaluating the breeding potential of individual fish [7]. However, studies have shown that egg production varies not only among species but also with the size and weight of the gonads, highlighting the importance of species-specific reproductive assessments [8,9].
Gonadosomatic index (GSI) and gonad volume are widely used as indicators of gonadal development and reproductive status in fish [10]. The liver, being the primary organ for detoxification, often exhibits morphological and enzymatic changes following exposure to environmental toxicants [11]. For instance, a decrease in hepatosomatic index (HSI) was observed in rainbow trout (Oncorhynchus mykiss) after nine weeks of paraquat exposure [12], whereas an increase in HSI was reported in both male and female tilapia (Oreochromis niloticus) under similar conditions, reflecting essential physiological functions [13]. Histopathological biomarkers, including changes in liver and gonad tissues, are generally considered reliable indicators of fish health and serve as mirrors of exposure to various anthropogenic pollutants [14]. GSI has long been used to estimate relative gonadal development, often assuming a constant arithmetic relationship between gonad weight and fish body weight [15,16]. Gonadal recrudescence in female fish involves the accumulation of lipids and proteins within developing oocytes, which contributes to reproductive readiness [17]. HSI is calculated as the ratio of liver weight to body weight, providing insights into metabolic and physiological status. Studies have shown that ovary weight increases significantly with body weight in goldfish (Carassius auratus) [16], and similar reproductive investigations have been conducted on freshwater eels in the Mymensingh region [17,18]. Despite these efforts, scientific information on the reproductive indices, particularly GSI and HSI, of cultured and wild Clarias gariepinus remains limited. Therefore, this study aimed to provide comprehensive data on the GSI and HSI of both cultured and wild C. gariepinus in the Makurdi Local Government Area of Benue State, Nigeria.
Materials and Methods
This experiment was carried out in two areas within the Makurdi Local Government Area. Makurdi the capital of Benue State lies between latitude 7° 41°N and longitude 08° 35°E. The locations were Owner Occupier quarter Makurdi for the cultured and Wadata landing site for collection of wild fish.
A total of 40 adult Clarias gariepinus were used in this experiment, it comprised of 20 cultured and 20 wild fish .The fish were obtained from Wadata landing site and Ogalahi’s farm wild and cultured strains respectively both in Makurdi, Benue state. Two plastic bowls were used to hold the fish during sample collection, a little water was poured in the bowl so that the fish will not die before been en properly killed. They were then taken to the general-Purpose Laboratory at the Department of Fisheries and Aquaculture, University of agriculture Makurdi for further work, where the fish were sacrificed and dissected the liver and gonad were removed and weighed and the GSI and HSI were calculated and compared. The liver and testis were weighed on a sensitive weighing balance individually for all the samples and were recorded.
The GSI was calculated by following formula given by [19] for both male and female fish. Same applies to the hepatosomatic index
Results
Table 1 shows the comparison between the body parameters of cultured and wild Clarias gariepinus for both sexes in the month of October. The result indicates significant differences except for the total length of the female.
Table 3 presents the comparison between the GSI and LSI for both sexes in cultured and wild Clarias gariepinus the comparison depicts significance differences with higher values occurring in the cultured than the wild
Discussions
The findings of this work showed that the GSI was higher in the cultured than in the wild, the highest GSI for females occurred in the cultured female in October and the least in the wild strain in October. Highest GSI in the Males occurred in October and least in December in the wild strain this may be as a result of better environmental conditions such as food availability, water temperature and salinity which are under control in the cultured and as a result of that better gonadal state these agrees with the work of [20] who identified the use of gonadosomatic index and volume of gonad as indicators of gonadal state.
The highest HSI in females occurred in the cultured strain and least in wild strain in December. Highest HSI in males occurred in the cultured strain in October and least in December in the wild strain the high HSI in the cultured fish may be as a result of higher quality feeding levels. This result disagrees to that of [12] found an increase of HSI in male and female tilapia, related to essential physiological functions, like O. niloticus, exposed to paraquat. The least in December in the wild strain may be as a result of high pollution this agrees with the findings of [10] who found a decrease in HSI values after 9 weeks in rainbow trout, Oncorhynchus mykiss, injected with paraquat. Higher LSI in the cultured fish may also be as a result of higher inclusion of carbohydrate in the diet of the cultured fish with low activity which may result to deposition of the excess carbohydrate in the liver. These also agrees with the work of [16] who reported that Gonadal recurrence in female fish involves accumulation of lipids and protein stores within the developing oocytes. It has been generally reported that histopathological biomarkers serve as reliable indicators of overall fish health, reflecting exposure to various anthropogenic pollutants [13]. This suggests that the hepatosomatic index (HSI) can be used as a rapid and practical indicator for detecting environmental pollution in aquatic ecosystems. Accordingly, HSI may be considered a valid and efficient measure for monitoring the impact of such pollutants on fish populations. When GSI and HSI of both cultured and wild strains were compared, we came to know that have maximum values of GSI and HSI occurred in culture than in the wild except for females in December.
This work has shown that the GSI and HSI of Clarias gariepinus in the cultured and the wild are not similar, with higher levels occurring in the cultured than in the wild except for females in December. The data from this work can serve as a baseline data for comparison between the GSI and HSI in cultured and wild Clarias gariepinus found in Western African which in turn can be used in the assessment of the effects of toxins and indication of wellbeing in the Clarias gariepinus of West African.
Conclusion and Recommendation
The present study revealed that the gonadosomatic index (GSI) and hepatosomatic index (HSI) of Clarias gariepinus were generally higher in cultured populations compared to their wild counterparts, suggesting better reproductive and physiological conditions under controlled aquaculture systems. These findings indicate that aquaculture practices, including proper feeding, management, and reduced exposure to environmental stressors, positively influence gonadal development and liver function in this species, wild populations may experience reduced GSI and HSI due to natural environmental variability, exposure to pollutants, and limited food availability. Based on these results, it is recommended that indiscriminate disposal of toxicants and industrial effluents into water bodies be strictly controlled to prevent adverse impacts on fish health and reproduction, regular monitoring of GSI and HSI in both cultured and wild populations should be conducted as a part of sustainable fisheries management and environmental assessment programs to ensure the long-term viability of C. gariepinus stocks.
References
- Antonio, J., Ellerbroek, A., Silver, T., Vargas, L., & Peacock, C. A. (2015). A high protein diet (3.4 g/kg/d) combined with a heavy resistance training program improves body composition in healthy trained men and women. Journal of the International Society of Sports Nutrition, 12(39). https://doi.org/10.1186/s12970-015-0100-0
- Azadi, M. R and Siddique, M. S. (1986). Fecundity of cat fish, Heteropneustes fossilis (Bloch) Bangladesh J. Zool. 14: 33-39.
- Doha, S. and Hye, M. A. (1970). Fecundity of Padma river hilsa, Hilsa Ilisha (Hamilton). Pakistan Journal of Science. 22(3-4): 176-178.
- Eyo,V.O, Ekanem A.P, Jimmy,U,U (2014). A Comparative Study of The Gonado-Somatic Index (GSI) And Gonad Gross Morphology of African Catfish (Clarias Gariepinus) Fed Unical Aqua Feed and Coppens Commercial Feed Page 10 of 12 – Integrity Submission Submission ID trn:oid; 3117:514607274
- FAO (2012): The state of the world fisheries and aquaculture. Food and Agriculture Organisation of the United Nation, Rome, pp 3 – 41.
- Islam, M.R., Sultana, N., Hossain, M.B., Mondal, S. 2012. Estimation of Fecundity and Gonadosomatic Index (GSI) of Gangetic Whiting, Sillaginopsis panijus (Hamilton, 1822) from the Meghna River Estuary, Bangladesh. World Appllied Science Journal 17(10) 1253-1260.
- Akter, H., Islam, M.R., Belal Hossain, M. 2012. Fecundity and gonado-somatic index (GSI) of Corsula, Rhinomugil corsula Hamilton,1822 (Family: Mugilidae) from the ml Lower Meghna River Estuary, Bangladesh. Global Veterinaria 9(2) 129-132.
- Kulshrestha, S. K., Adholia, U. N., Bhatnagar, A. and Khan A. A. (1990). Length weight relationship Wallago attu (Schneider) with reference to certain environmental conditions from selected river of Madhya Pradesh and Rajasthan. Environ. And Ecol. 8(4): 1190-1194.
- Gumus E, Ikiz R. (2009). Effect of dietary levels of lipid and carbohydrate on growth performance, chemical contents and digestibility in rainbow trout, Oncorhynchus mykiss. Pakistan Veterinary Journal. 29(2):59-63.
- Kime (1998) Endocrine disruption in fish Kluwer Academic publisher
- Akerman G.P.,Amcoff U,Tjanlund.,K.Forgeberb,O.T,Balk, L (2003) Paraquat and menadione exposure of rainbow trout. Studies of effects on the penthose phosphate shunt and thiamine levels on liver and kidney Chem.Int142:269-283
- Figueiredo-FernandezA.A.,Fountainhas-FernandezF.PeixotoE.RochaM.A.,Reis Henrinque (2006).Effects of paraquat on oxidative stress in Tilapia (Oreochromis niloticus) at two levels of temperature .pest Biochem.physol.,85:97-103
- Vander Oost R.V.,J.Bayer and N.P.E Vermeulen (2003).Fish bioaccumulation and bio makers in environmental risk assessment a review.Environmental toxicology and pharmacology 13:57- 149
- Meien V.V.,(1927).Observation of the yearly variations on the ovaries in the perch (Perca fluvuiatilus) Russk.Zool.Zh.7 Vyp.4.
- Manboob and Sheri A.N (2002). Relationship among gonad weight, liver weight and body weight of major, common and some chinesecarps under composite culture system with special reference to pond fertilization Asian- Aust .J.Anim.Sci.2002.Vol 15No 5:740-744
- Manboob S.,NSheri and M.Javed (1990).Observation on the biology of Cyprinus carpio The 10th Congress of zoology 26-27 may Khanspur (mauree) Pak.J. Zoo.Abstract series No 10 Page 11 of 12 – Integrity Submission Submission ID trn:oid: 3117:514607274
- Delunty G.and Devlaming V.L(1980) Seasonal relationships of ovary weight ,liver weight and fat stores with body weight in the gold fish, Carrasus auratus J.Fish BIOL.16:5-13
- Narejo, N.T. 2003. Comparative studies on the biology and culture of Monopterus cuchia and Mastacembelus armatus of Mymensingh region. PhD thesis, Department of Aquaculture, Bangladesh Agricultural University, Mymensingh, Bangladesh. pp. 205.
- Parmeswaran, S. C., Selvaraj and S Radhakrishanan. 1974. Observation on the biology of Labeo gonius (Hamilton) Indian J. Fish. 21: 54-75.
- Saksena,D.N.(1989).The use of gonadosomatic index and volume of the gonads as indicators of gonanadal state in india fresh water goby, Glossogobius giuris (Ham) with a note on the role of temperature in the fish reproduction Intl.J. Ichthyol.8(1):1-8.
