Monthly Archives: novembre 2025

*Morfow Nkeze Paul¹, Benedicta Oshuware Mbu Oben², Friday Elijah Osho³, Nor Azman Kasan^1*

¹⁾ Higher Institution Centre of Excellent (HICoE), Institute of Tropical Aquaculture and Fisheries, Universiti Malaysia Terengganu, 21030 Kuala Nerus, Terengganu, Malaysia.

² Department of Animal Sciences, University of Buea, Republic of Cameroon

³ Department of Aquaculture and Fisheries Management, University of Ibadan

Corresponding author*: mopaze2002@yahoo.com

Abstract

Shrimp farming is a key player in global aquaculture, driven by efficient and sustainable production technologies. Biofloc Technology (BFT) has emerged as a pivotal solution to various aquaculture challenges, offering a cost-effective and environmentally friendly approach. BFT enhances water quality by promoting the growth of heterotrophic bacteria, which help reduce ammonia levels and improve biosecurity. It also minimizes water exchange, conserving vital water resources in areas facing scarcity. However, while BFT has proven highly beneficial for shrimp farming, it presents challenges such as the risk of disease outbreaks, potential overcrowding, and management complexities. This review evaluates the advantages and limitations of BFT, highlighting its impact on water quality improvement, biosecurity enhancement, and water conservation. It also discusses the need for optimized system management to mitigate disease risks and overcrowding issues. Recommendations include the use of appropriate carbon sources for microbial mass management, species selection tailored to BFT, and potential integration of alternative energy sources to reduce operational costs. This review emphasizes BFT’s potential as a sustainable solution for small- and medium-scale aquaculture operations while acknowledging the necessity of addressing system challenges to maximize its efficacy.

Keywords: Aquaculture sustainability, Biofloc Technology, Disease management, Shrimp farming

Tombuh Divine Ngala* et Tangem Lucas Leku

Unit of Aquaculture, Ministry of Livestock, Fisheries and Animal Industries (Minepia), Cameroon

*Correspondence to: Email:dntombuh@yahoo.co.uk; tel: 0023766330000/675730100

ABSTRACT

 The fish feed production sector in the Centre and Littoral Regions of Cameroon faces several challenges that affect the quality of the feed produced and the growth rates of the fish. The drying and storage process of the feed is inadequate, leading to spoilage due to high moisture content. Most of the fish feed production units have a moisture content that ranges between 10.5% and 18.3%, which is higher than the recommended 10% or less. The cost of production has increased due to the high prices of both local and imported raw materials, such as soybean, corn, fishmeal, fish oil, rice, and wheat. The use of well-ground raw materials in fish feed formulation is essential for ensuring the overall quality of the feed and the growth rates of the fish. However, during visits to fish feed production units, it was found that 80% of them did not use well-ground raw materials. The lack of heating units or worn screws in extruders resulted in inadequate temperature control during the extrusion process, which affected the gelatinization of starches and proteins, leading to poor pellet formation, increased feed waste, and reduced feed efficiency. The fish feed produced did not meet the nutritional requirements of the fish, with more than 80% of the local feed analyzed having crude protein levels less than 30%. The local fish feed production sector faces intense competition from imported fish feed, leading to market saturation and reduced profitability for local producers. The lack of low-cost and readily available raw materials was another challenge that the fish feed industry faced. The nutritional composition labeled on fish bags did not match the results of the analysis after assessing some fish feed production units. Additionally, the cost of local or domestic fish feed per kilogram ranges from 1000CFA to 1100CFA, while imported feed costs between 1200CFA and 1400CFA. Despite the higher cost, 70% of fish farmers in Cameroon prefer to use imported fish feed due to its better feed conversion ratio, which they believe promotes the growth of their fish species. The local fish feed production sector faces several challenges that need to be addressed to improve the quality of the feed produced and the growth rates of the fish. Statistical analyses show that the sector needs to focus on improving the drying and storage process, using well-ground raw materials, and ensuring adequate temperature control during the extrusion process. The sector also needs to address the issue of low crude protein content in feed meals, the lack of low-cost and readily available raw materials, and the competition from imported fish feed. The government needs to provide support to the local fish feed production sector to improve its competitiveness and ensure food security.

Keywords: Fish feed production, Cameroon, challenges, quality, and growth rates.

TANGEM LUCAS LEKU (+237674930502, tangemlucasleku@gmail.com)

Professional Master of Engineering in Fisheries and Aquatic Sciences, Option Aquaculture and Master of Science in HYDROBIOLOGY AND ENVIRONMENT, LABORATORY OF HYDROBIOLOGY AND ENVIRONMENT,

DEPARTMENT OF ANIMAL BIOLOGY AND PHYSIOLOGY, FACULTY OF SCIENCE, UNIVERSITY OF YAOUNDE I.

TANGEM LUCAS LEKU, OMGBA MARIE THÉRÈSE VIVIANE, MPOMEZOK CHILLY VANESSA GABY, NYAMA JOSEPH, TAMPONO IDEDOU CHRISTELLE.

MINISTRY OF LIVESTOCK, FISHERIES AND ANIMAL INDUSTRIES

YAOUNDE, CAMEROON.

Abstract

The study evaluated water quality and macroinvertebrate biodiversity in four (04) fish ponds at the Obili Aquaculture Unit, Centre Region of Cameroon, from June 2022 to November 2022. Monthly sampling was carried out, measuring physico-chemical parameters according to Rodier’s guidelines and collecting benthic macroinvertebrates using a multihabitat approach. Results indicated poorly oxygenated, slightly acidic water conditions, which are unfavorable for aquatic species production, along with low levels of organic pollution indicators such as nitrates, orthophosphates, and nitrites. A total of 532 macroinvertebrates were identified, spanning two phyla, two classes, six orders, and ten families. Insects dominated the community, comprising 51.7% relative abundance across four orders and eight families, followed by Gastropoda, which accounted for 48.3% relative abundance across two orders and two families. Spatial-temporal analysis revealed the presence of pollution-tolerant taxa, including Lestidae, Thiaridae, and Lymnaeidae, indicating excessive organic pollution. Diversity indices (Shannon-Weaver and Pielou’s equitability) reflected low taxa diversity, caused by unfavorable conditions for pollution-sensitive species. Hilsenhoff’s Biotic Index confirmed significant organic pollution across all ponds. The Global Biotic Numeric Index (GBNI) indicated poor water quality in the fish ponds, while Sörensen’s similarity coefficient (>50%) showed high similarity among ponds.

. Finally, the study suggests promoting macroinvertebrate cultivation as a viable alternative to fishmeal in aquaculture feed.

Key words: Biodiversity, Benthic Macroinvertebrates, Water quality, Fish ponds, Obili.

TANGEM LUCAS LEKU (+237674930502, tangemlucasleku@gmail.com)

TANGEM LUCAS LEKU, OMGBA MARIE THÉRÈSE VIVIANE, MPOMEZOK CHILLY VANESSA GABY, NYAMA JOSEPH, TAMPONO IDEDOU CHRISTELLE.

MINISTRY OF LIVESTOCK, FISHERIES AND ANIMAL INDUSTRIES

YAOUNDE, CAMEROON.

Abstract

The study evaluated water quality and fish biodiversity in four fish ponds at the Obili Aquaculture Unit, located in the Centre Region of Cameroon, from June to November 2022. Monthly sampling was carried out, with physico-chemical parameters measured following Rodier’s guidelines. A multihabitat approach was used for fish capture, employing nets to sample and count fish, which allowed estimation of total fish populations in each pond. Results indicated poorly oxygenated and slightly acidic water conditions, unfavorable for aquatic species production, along with low levels of organic pollution indicators such as nitrates, orthophosphates, and nitrites. The African catfish, identifiable by barbels, absence of scales, a single long dorsal fin, and dark grey coloration with a white ventral side, was present in all ponds. Pond 4 was stocked at a density of 20 catfish per square meter, corresponding to an estimated 8,000 catfish, while only a few Tilapia were observed there. Oreochromis niloticus, an omnivorous grazer feeding on phytoplankton, periphyton, aquatic plants, small invertebrates, benthic fauna, detritus, and associated bacterial films, outnumbered catfish in the other ponds. Catfish stocking was aimed at controlling tilapia populations. The Global Biological Normalized Index (GBNI) indicated poor water quality across the ponds, whereas Sørensen’s similarity coefficient (exceeding 50%) demonstrated good biological similarity among the ponds. Finally, the study suggests promoting macroinvertebrate cultivation as a viable alternative to fishmeal in aquaculture feed.

Key words: Biodiversity, fish, water quality, fish ponds, Obili.