Influence of partial replacement of fish meal with shrimp head meal or cassava leaf meal, without or with lysine supplementation on growth performance of hybrid catfish (Clarias macrocephalus x C. gariepinus)

Nguyen Duy Quynh Tram, Nguyen Khoa Huy Son, Le Duc Ngoan and Jan Erik Lindberg¹

Hue University of Agriculture and Forestry, Hue University, 102 Phung Hung, Hue City, Vietnam
¹ Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P O Box 7024, SE-750 07 Uppsala, Sweden
ndqtram@hueuni.edu.vn

Abstract

Fish meal (FM) were partly replaced by cassava leaf meal (CLM) or shrimp head meal (SHM) without or with lysine supplementation in practical diet for fingerling of hybrid catfish (Clarias gariepinusxC.macrocephalus) (3.8±0.5g). The control diet was based on FM (Ctr l), while the four experimental diets were: replacing 50% of FM by CLM without or with lysine supplementation (CLM, CLM-Lys); and similarly, FM was also replaced by SHM without or with lysine supplementation (SHM, SHM-Lys). Five diets were formulated to obtain isoenergetic (gross energy, 19 MJ kg^-1) and isonitrogenous diets (crude protein content, 300 g kg^-1). Each diet was test in three replicate groups of 30 fish during 60-day feeding trial. Results show that survival rates ranged from 93.3 to 96.7%. A highly significant difference in final weight (FW) and specific growth rate (SGR) between diets (p<0.001) were observed. FW and SGR were significantly higher for fish fed the SHM-Lys diet than the others. In contrary to SHM, replacing 50% FM results in low FW and SGR (p<0.001). Significant higher growth performance and SGR were observed in fish either fed CLM or SHM with lysine supplementation than that of fish fed diet without lysine supplementation. Feed efficiency ratio and protein efficiency ratio were not significantly affected across treatments (p>0.05). Concerning carcass composition, there was no significant differences in moisture, crude protein, ether extract and ash content.

Keywords: carcass composition, feed efficiency, replacement

Introduction

In fish farming, feed costs represented 40-60% of operation costs (Tacon and Jackson 1985), thus fish nutrition investigations are mainly directed towards reducing feed cost by manipulating the feed formulation (Viola and Arieli 1992). It is clear that alternative, less expensive sources of good quality protein must be explored. The efficiency of the various alternative protein sources as partial or complete dietary replacement for FM has been evaluated in fish diets, e.g. poultry by-product meal, meat and bone meal, blood meal (Webster et al 1999; Hu et al 2008), soybean meal, cottonseed meal, sunflower meal, linseed meal (Tidwell et al 1993; Davies et al 1997; El-Saidy and Gaber 2003), shrimp head meal (SHM) (ElSayed 1998; Rachmansyah et al 2004; Chimsumg et al 2006; Oliveira et al 2007), and a few works with cassava leaf meal (CLM) (Ng and Wee 1989; Bureau et al 1995). Most of the fish under those studies were rainbow trout (Gomes et al 1995; Kaushik et al 1995; Davies et al 1997; Yoshitomi et al 2007), African catfish (Bureau et al 1995; Nwanna et al 2004; Goda et al 2007; Nyina-wamwiza et al 2007; Nyina-Wamwiza et al 2010), Nile tilapia (Rodríguez-Serna et al 1996; El-Saidy and Gaber 2003; Goda et al 2007), European seabass (Kaushik et al 2004), and red drum (Davis et al 1995) but there was previously no study on hybrid catfish.

In Vietnam, shrimp by-products from the shrimp industries are an important animal protein source after FM. It was estimated in 2022 that 325 thousand tons of shrimp by-product were produced (Pham Duy Hai 2022). SHM with high protein content, is considered to be a valuable protein source for animal (Balogun et al 1996) and previous studies have showed that SHM is a potential protein source for fish (Cruz-Suárez et al 1993; Chimsumg et al 2006; Nargis et al 2006; Oliveira Cavalheiro et al 2007). Moreover, the apparent digestibility of protein from SHM is quite high (78-96%) and even not much lower than FM (Laining et al 2003; Tram et al 2011). Different results were obtained when fed SHM to differences fish species, where SHM can be included up to 50% in the diet for red tilapia (Chimsumg et al 2006), but FM can only be replaced with up to 20% of chemically ensiled SHM in the diets of African catfish (Nwanna et al 2004). However, lysine and methionine concentrations in SHM are very low Cassava (Manihot esculentaCrantz) is the second most important food crop after rice in terms of total production (GSO, 2009). Cassava leaves can be harvested at root harvest time or from 3- 4 months of age in a cycle of 60- 75 days (Phuc and Lindberg, 2001). Cassava leaves have high level of CP (20 – 30 % in DM) and is a good source of protein for animal but high content of cyanide limits their use as an animal feed (Rawindran 1993). Drying of cassava leaves will markedly reduce HCN content. However, dried cassava leaves are low both lysine and methionine (Phuc and Lindberg 2001).

Lysine is one of ten essential amino acids that must be provided by the diet, especially when formulating the diets containing a large percentage of protein from plant sources (SRAC 1993). Earlier study by Tram et al (2011) found that dietary lysine requirement of hybrid catfish was 1.65% of dry diet. Therefore, the aim of the present study was to evaluate the suitability of cassava leaf meal or shrimp head meal as a partial substitute for a fish meal diet without or with lysine supplementation for hybrid catfish fingerling, Clarias macrocephalus x C. gariepinus.

Materials and methods

Fish and culture condition

The experiment was conducted in a fish farm in Thuy Van, Huong Thuy, Thua Thien Hue, Vietnam. Hybrid catfish (Clarias macrocephalus x C.gariepinus) fingerling were obtained from Provincial Breeding Centre (Thua Thien Hue, Vietnam). A total of 450 fingerlings, with an initial body weight of 3.8±0.5g, was randomly distributed to 15 net cages (2m x 1m x 1.4m), at a density of 15 fish m³. Three replicate net cages per dietary treatment were used. The fish were adapted to the experimental conditions for one week before the start of the experiment. During that period, they were fed with commercial diet (Lai Thieu, DT02, 35% crude protein) twice a day. The actual experimental period lasted for 60 days. During the experimental period, all fish were fed with their respective diets at a level of 5% of body weight. The daily feeds were divided into two equal amounts and given to the fish at 08:00 and 16:00 hours. Random samples of fish from each experimental treatment were weighed every 15 days and feed ration was adjusted accordingly.

Feed ingredients

CLM and SHM used in this study were prepared similar to the previous study (Tram et al 2011), CLM are from sweet variety. The other ingredients were obtained from local feed shops. They were subjected to analyses for proximate composition, gross energy and amino acids (Table 1).

Experimental diet

Five experimental diets were formulated on a dry weight basis to contain 30% CP and 19 MJ kg^-1gross energy. The diets were formulated to be isonitrogenous and isocaloric by adjusting proportion of cassava root meal, fish oil and vegetable oil. The control diet was formulated based on fish meal. The test diets were replaced 50% fish meal with either CLM or SHM without or with lysine supplementation to meet the dietary lysine requirement of hybrid catfish (Tables 2 and 3).

Water quality and fish sampling

Water temperature was recorded daily using a mercury thermometer suspended at 20-cm depth. Dissolved oxygen (DO), pH and ammonia were measured by a test kit (Advance Pharma Co Ltd., Thailand). In which, DO and pH were measured twice daily and ammonia was recorded at weekly intervals.

At the beginning of the feeding trial, a pooled sample of 30 fish was collected from the fingerling batch to serve as an initial carcass sample. At the end of the feeding trial, 10 fish were sampled at random from each cage and anaesthetized in a bath of 0.05 ml L^-1 FA 100 (4 allyl-2-methoxyphenol) and stored at -20^oC until analyzed.

Chemical analyses

Diets, ingredients and carcass samples were analyzed in duplicate for proximate composition (AOAC 1990). Samples were analyzed for dry matter (DM) by drying fresh samples at 105^oC for 24 hours. Total nitrogen (N) was determined by the Kjeldhal method (Kjeltec system, Tecator, Sweden) and crude protein (CP) content was calculated as N*6.25. Ether extract (EE) was determined by Soxhlet extraction without acid hydrolysis. Ash was the residue after ashing the samples at 550-600^oC. Fibre content was determined using acid-base digestion (AOAC, 1990). Gross energy was measured using an automated bomb-calorimeter (Calorimeter Parr 6300, USA). Amino acid analysis was performed using high-pressure liquid chromatography (MoST 1990) by a commercial company (Sac ky Hai Dang Science Technology services Joint Stock Company, Ho Chi Minh City).

Calculation of parameters

The growth performance and feed efficiency were determined according to Hepher (1988) as follows:

- Specific growth rate (SGR) = 100 x (LnW_t-LnW_o)/t, where W_tis final body weight, W_o is initial body weight, t is experimental duration in day

- Protein efficiency ratio (PER) = wet weight gain (g)/protein fed (g)

- Feed efficiency ratio (FER) = wet weight gain (g)/dry feed fed (g)

- Survival rate = [(final number of fish)/(initial number of fish) x 100]

Statistical analysis

All the data were subjected to analysis of variance according to the General Linear Model procedure of the Minitab Reference Manual Release 16.2.0 (Minitab, 2010). Tukey pair-wise comparison were used to determine differences between treatment means at p<0.05.

Results and discussion

Water quality parameters

The water temperature ranged from 24.5 to 31^oC, DO from 3.5 to 6.5 mg L^-1, pH from 6.1 to 6.9 and total ammonia from 0.2 to 0.55 mg L^-1. Results of the resent study demonstrated that water quality parameters were within the acceptable range for catfish growth (Stickney 1979) and indicated water quality did not produce any stress on fish during the experiment.

Chemical analysis of feed ingredients and the diets

Proximate and amino acids composition of CLM and SHM are shown in Table 1. The protein content of CLM was 25.1%, SHM contained high level of protein (47.3%) and ash content (26.4%). CLM contained low level of lysine (0.79%) compare with FM and SHM (4.07 and 2.11%, respectively).

The proximate composition of the experimental diets is shown in Table 2. In order to obtain the isoenergetic (gross energy, 19 MJ kg^-1) and isonitrogenous diets (crude protein content, 300 g kg^-1), the proportion of fish oil, vegetable oil, cassava root meal, and rice bran were adjusted, thus the ether extract levels were variation between the diet, the lowest was in CLM diet (12.1%) and the highest was in SHM diet (26.2%). The crude fibre (CF) and ash content were also different between the diets, the diets substituted CLM had high CF (8.2 and 7.9 % in CLM and CLM-Lys diets, respectively) while ash content was high in SHM diet (12.2-12.5%).

The essential amino acids of the control and experimental diets are shown in Table 3. Level of lysine was range from 1.25 to 1.69% of the dry diet.

In comparison with FM, CLM and SHM used in this study had lower protein content (25.1 and 47.3%, respectively). The protein content of CLM was 25.1%, much higher than the value (14.3%) reported by Bureau et al (1995) but was comparable to other publish data (Ravindran 1995; NIAH 2001). SHM contained high level of protein (47.3%) and ash content (26.4%), these values fall into the range of results of other authors (Balogun and Akegbejo-Samsons 1992; Ngoan 2000). CLM had higher crude fibre compared to FM, crude fibre of SHM was unable to detect in this study.

The hybrid Asian-African catfish is rapidly popularity in Southeast Asia due to its rapid growth, resistance to disease, stocked at high density and excellent meat quality. Thus, using locally available feedstuffs in the diet could improve the economic feasible of cultured this species (Ng and Chen 2002).

Growth performance and feed efficiency

The results obtained with the experimental trial are presented in Table 4. Final survival was higher than 93% for all treatments. Fish growth performance displayed highly significant differences (p<0.001) between diets. The fish fed diet SHM-Lys produced significantly higher final weights and specific growth rate (SGR) than fish fed diet SHM, Ctrl, CLM-Lys, CLM. In contrary to SHM, replacing 50% FM results in low FW and SGR (p<0.001). Significant higher growth performance and SGR were observed in fish either fed CLM or SHM with lysine supplementation than that of fish fed diet without lysine supplementation. Feed efficiency ratio (FER) and protein efficiency ratio (PER) were not significantly affected by the treatments (p>0.05).

The results indicated that supplemental lysine (3-4 g kg^-1) was effective in improving the nutritive value of CLM and SHM and could fulfil the requirements of hybrid catfish (Unprasert 1994 cited in Wilson (2002); Tram et al 2011). It is interesting to note that weight gain and SGR were significantly higher in fish fed diet CLM-Lys and SHM-Lys, these similarly with the results obtained by Bai and Gatlin (1994) and Hansen et al (2010) but in contrast with the report of Saavedra et al (2009) who found that supplement tryptophan and lysine did not improve growth performance of Diplodus sargus larval. Several researches have been conducted on the replacement of FM with SHM, chemically preserved SHM and shrimp head silage powder (Nwanna et al 2004; Rachmansyah et al 2004; Chimsumg et al 2006; Oliveira Cavalheiro et al 2007). The results were different between studies, with African catfish, SHM can be only replaced up to 20% of FM in the diets, while tilapia showed better capacity to utilize SHM (50 to 100% in the diet) and only 10% of SHM can substitute FM in the diet of humpback grouper.

Figure 1. Effect of treatment on SGR

Figure 2. Effect of treatment on DWG

The lowest growth performance, DWG and SGR (Table 4, Fig 1and Fig 2) of fish fed diet CLM suggest that this feed is less appropriate for Clarias hybrid fingerling. This could be due to high fibre content of cassava leaf meal, which is known to reduce feed intake, as reported in monogastric animals (Jacquot and Ferrando 1957 cited by Nyina-wamwiza et al 2007). Other factors could be this diet was less palatability and digestibility of cassava leaf meal and presence of cyanogenic glycosides, which release toxic hydro-cyanogenic acid on hydrolysis (Francis et al 2001; Tram et al 2011).

There is less information available on the use of CLM in the diet for fish, except studies by Ng and Wee (1989) on tilapia and Bureau et al (1995) on African catfish, Clarias gariepinus. Bureau et al (1995) fed African catfish three diets consisting CLM at levels of 0, 10 and 20%, he found that there were not significant difference between diets on growth performance but fish fed the 20% CLM diet showed sensitive with disease.

Fish carcass chemical composition

The results of fish carcass composition are presented in Table 5. Statistical analysis of the results shows that dietary treatments did not affect carcass composition (p>0.05).

The ether extract (EE) content of the experimental diets was variation, range from 11.8 to 26.2%. High level of EE contents in the SHM and SHM-Lys diets because of high level of fish oil and vegetable oil used in these diets in order to obtain the same gross energy content among diets. Lim et al (2001) have shown that about 18% dietary crude lipid was acceptable in C. gariepinus diet. Berge and Storebakken (1991) fed Atlantic halibut two different dietary fat content (12 and 21%) and found that no significant differences in growth performance, feed efficiency and fillet composition. In present study, EE content in fish carcass was not affected by dietary EE, this is in accordance with results reported by Hillestad et al (1998), who stated that large differences in dietary fat (22 and 30%) level did not affected the dressed carcass fat content in Atlantic salmon but those difference with the results obtained from Sæther and Jobling (2001) and Nyina-wamwizaet al (2007).

Furthermore, in the present study, there was no difference in carcass composition between fish fed the control diet and experimental diets without of with Lys supplementation. The results were in agreement with Hu et al (2008) but contracted the study of Cowey (1995) which indicated that crystalline - amino acids (AA) were different from protein-bound-AA and may affect animal protein synthesis.

Conclusion

In conclusion, the results from this study show that SHM provide better nutritive value than CLM, and fish achieved better growth performance when Lys was added into the diet. Replacing 50% FM by CLM reducing fish growth performance compare with control diet. The present study was, however, conducted with hybrid fingerling from 3.8 to 22.8 g body weight. More studies are thus needed to evaluate the long-term effects of such experimental diets in hybrid Clarias growth performance.

Acknowledgments

We are grateful to the Swedish International Development Agency- Department for Research Cooperation (Sida - SAREC) for financial support.

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