Influences of Biochar and dietary rice distiller's grain (HEM) level on growth performance of Striped catfish (Pangasianodon hypophthlamus)

T T Lan¹, N H Y Nhi¹ and T R Preston²

¹ Department of Aquaculture, Faculty of Agriculture and Natural Resources, An Giang. University, Viet Nam National University Ho Chi Minh City, 18 Ung Van Khiem, Dong Xuyen ward, Long Xuyen city, An Giang province, Viet Nam
ttlan@agu.edu.vn
² Centro para la Investigación en Sistemas Sostenibles de Producción Agropecuaria (CIPAV), Carrera 25 No 6-62 Cali, Colombia

Abstract

A 12-week feeding trial was conducted to evaluate the effects of dietary biochar and rice distiller's by-product level as a source supplement prebiotic on growth performance of striped catfish (Pangasianodon hypophthalmus). Triplicate groups, each of 30 fish (13.3g) were randomly assigned to 18 tanks (500-L). Six iso-nitrogenous (30%) diets were formulated to contain grades levels of biochar were 0%, 1% and rice distiller's byproduct were 0%, 2%, 4% (designated as B0H0, B0H2, B0H4, B1H0, B1H2 and B1H4). The water quality parameters such as temperature, pH, DO were monitored during the experimental period. At the end of the experiment, feed intake, protein intake, weight gain, daily weight gain, specific growth rate, feed conversion ratio, protein efficiency ratio and survival rate of fish were determined. The results showed that the water quality factors contained temperature, pH, DO, TAN, NO₂ ^- were within the suitable range for the growth of fish. Growth performance of striped catfish was increased when the level of biochar and rice distiller's by-product increased in the diets. In addition, the growth performance of striped catfish was significantly different in all treatment diets (p<0.05). Feed conversion ratio were, however, increased in diets have the level of biochar and rice distiller's by-product reduced. Survival ratio were not significantly different in all treatments (p>0.05). Base on this, we concluded that biochar and rice distiller's by-product were possible supplement into the diets for striped catfish as a prebiotic to improve growth performance.

Key words: biochar, Hem, growth performance, rice distiller's by-product

Introduction

Rice distiller's grains from ethanol plants has been used as livestock feed for many years. Feed conversion efficiency in fish, however, is typically much higher compared to traditional livestock. But, the cost of fish feed is one of the challenges for profitable fish cultivation. Due to the exponential growth of ethanol plants in recent years, rice distiller's grains is becoming readily available as a reasonably-priced base material for animal feeds, and because it has a relatively high protein content, it also has much potential for use as a fish feed ingredient.

Rice distillers dried grain (RDDG) or HEM is a cereal by-product which is fermented and distilled to obtain alcoholic beverage (Hertrampf and P Pascual 2000). The DDG has been documented as a promising feed ingredient in the poultry and livestock industries (Cheeng and Hardy 2004; Jacob et al 2008) because it is highly nutritious and economical. Researchers have worked with incorporation of DDG in aquafeed (Chevanan et al 2007; Kannadhason et al 2009). The enhanced availability and potential cost-benefit of DDG in aquafeed presents a substantial economic value as it is less expensive than other protein/energy sources like soybean meal (He et al 2013). However, little information is available on the potential use of RDDG from rice for striped catfish. Some researches has shown that RDDG was supplemented in diets for Chanal catfish (Lim et al 2009; Li et al 2010), Tilapia (Shelby et al 2008), Juvenile red Seabream (Jin Choi et al 2014).

Recent research also shows that when adding biochar to the diet of striped catfish improved fish growth rate and water quality (Lan et al 2016).

Materials and methods

The experiment was conducted in experimental farm of Aquaculture Department, Faculty of Agriculture and Nature resources, Angiang University, An Giang province, Vietnam.

Experimental treatments and design

The treatments were arranged as a 3*2 factorial with 3 replications in a completely randomized design (CRD) and 1 control treatment. Individual treatments were:

Treat B0H0 (control treatment): No Biochar and no HEM
Treat B0H2: No biochar, HEM2%
Treat B0H4: No biochar, HEM4%
Treat B1H0: Biochar 1%, no HEM%
Treat B1H2: Biochar 1%, HEM2%
Treat B1H4: Biochar 1%, HEM4 %

Seed and equipments

Pangasius fry were bought at the hatchery farm in An Giang province and reared until 10 g to use in this experiment. 20 tanks with volume 500 liters per tank were used for this experiment.

Stocking density were 50 Pangasius fingerling per tank.

Biochar was made by combusting rice husk in an updraft gasifier stove (Olivier 2010), HEM (rice distiller's grain) were bought from the alcohol product smallhouse. Then filter through cloth to remove water, take the residue and dry it in the sun, then dry in an oven at a temperature of 60 - 80^oC. The dry HEM is taken out and ground finely, then the feed is mixed according to the formula of each treatment.

Feeding and management

Feed were made from fishmeal, soybean meal, maize (30% protein with DM) and mixed with biochar (1%) and rice distiller's grain levels (HEM) (table 1). Fish fed at adlibitum. Fish weight were measuered every month.

Water were exchanged every twice days.

Figure 1. Feed after mixing and grinding into pellets

The residual feed and fish excreta in the tanks were removed by siphoning and fresh water was added before feeding in the morning. Fish weight were measured every month.

Measurements

The fish were weighed at the beginning the trial and after finished as well as during experiment period at monthly to determine DWG, SR, FCR.

Daily weight gain (DWG) was calculated as:

DWG (g/day) = (w_f- w_i)/T ……………….(ii)

Feed conversion ratio (FCR) was calculated as:

FCR = Feed DM offered/weight gain of fish …..(iii)

Survival rate (SR%) was calculated as:

SR (%) = 100[number of fish harvested/initial number of fish] …….(iv)

Water parameters were measured weekly including pH, NO₂ ^- , COD, PO₄^3-, DO, temperature in the morning before exchanging water.

Chemical analysis

Feed offered were determined dry matter (DM), OM, ash, lipid and N (AOAC, 1990).

Water quality including pH, NO₂^-, COD, PO₄^3-, DO, temperature were collected and analyzed according to APHA (1995).

Statistical analysis

The data were analysed by use a Minitab program with general linear model (GLM) option (version 16.0) ANOVA software (Minitab, 2016). Analyse variation are source of biochar or Hem (RDG), treatments and error.

Results and discussion

Water quality parameters during the experiment

Temperature, pH and DO in the treatments during the experiment were within the appropriate range for the growth of Pangasius (Nguyen Dinh Trung, 2004). The temperature fluctuates in the morning 25.10-27.93 ⁰ C, in the afternoon 26.47-29.43⁰C. The highest pH in the morning is 7.21 and the lowest is 6.85. Oxygen content between treatments ranged from 3.51-7.72 mg/L in the morning and 3.40-6.99 mg/L in the afternoon.

Most of the water quality indicators in the treatments were not statistically significant. The water quality is good and suitable for the growth of Pangasius fish. The results of measuring environmental parameters showed that treatment B1H4 had better water environment indicators than the remaining treatments. So when adding 40g/1000g of wort and 10g/1000g of biochar to the feed, the farming environment is better.

Growth performance of Pangasius fish when supplemented HEM and Biochar with different concentrations into the feed fish

The initial average weight of the fish was not statistically different between the treatments (p>0.05), which showed that the experimental catfish had a uniform weight. However, after 12 weeks of experiment, the average weight of fish in the treatments was statistically different (p<0.05). The daily weight gain (DWG) was highest in the B1H4 treatment and the lowest was in the B0H2 treatment (Figure 2). The absolute growth rate between the treatments was statistically significantly different (p<0.05). This showed that adding biochar and HEM to fish diets has a positive effect on the growth of Pangasius. Adding 1% biochar to fish feed makes the fish have better digestive ability, improves the culture water so the fish grow well (Lan et al. 2016) and combining the addition of HEM as a prebiotic helps the fish have better digestion also contributes to improved fish growth.

Figure 2. Daily weight gain of fish supplement HEM at difference levels with and without Biochar in feed

Survival rate and feed conversion ratio

The difference in survival rate of Pangasius between treatments was not statistically significant. The most effective (lowest) feed conversion rate was in the treatment with HEM and biochar content in the treatment B1H4 and had a statistically significant difference between the rest treatments (p<0.05) (Figure 3). These showed that when feeding feed supplemented with HEM and biochar has a positive effect on fish's feed utilization efficiency but does not affect survival rate.

Figure 3. Feed conversion ratio of fish supplemented HEM at different levels with and without Biochar in feed

Conclusion

• Adding biochar at 1% and HEM 4% to feed helps catfish grow best.
  
  
• FCR is also best when supplemented with 1% biochar and 4% HEM.
  
  
• There was no effect on survival rate between treatments when adding biochar and HEM to the feed.

References

AOAC 2000 Official methods of analysis of AOAC International (17th ed.), AOAC International, Gaithersburg, MD, USA (2000).

APHA 1995 Standard Methods for the Examination of Water and Waste Water. 18th Edn., American Public Health Association, Washington, DC, USA.

Cheng Z J, Hardy R W 2004 Nutritional value of diets containing distiller's dried grain with solubles for rainbow trout (Oncorhynchus mykiss). J Appl Aquac. 15:101-113.

Chevanan N, Rosentrater K A, Muthukumarappan K 2007 Twin-screw extrusion processing of feeds blends containing distillers dried grains with solubles (DDGS). Cereal Chem. 84:428-436.

Chevanan N, Rosentrater K A, Muthukumarappan K 2010 Effects of processing conditions on single screw extrusion of feed ingredients containing DDGS. Food Bioprocess Technol.3:111-120.

He S, Wu Z, Liu Y, Wu N, Tao Y, Xu L, Zhou Z, Yao B, Ringø E 2013 Effects of dietary 60 g kg ^-1 dried distiller's grains in least-cost practical diets on production and gut allochthonous bacterial composition of cage-cultured fish: composition among fish species with different natural food habits. Aquac Nutrition.19:765-772.

Hertrampf J W, Piedad-Pascual F 2000 Handbook on Ingredients for Aquaculture Feeds. Kluwer Academic Publishers; Boston, MA, USA: 2000. p. 573.

Jacob M E, Fox J T, Drouillard J S, Renter D G, Nagaraja T G 2008 Effects of dried distiller's grain on fecal prevalence and growth of Escherichia coli O157 in batch culture fermentations from cattle. Appl Environ Microbiol .74:38-43. [PMC free article] [PubMed]

Jin Choi, M d Mostafizur Rahman, Sang-Min Lee 2014 Rice Distillers Dried Grain Is a Promising Ingredient as a Partial Replacement of Plant Origin Sources in the Diet for Juvenile Red Seabream (Pagrus major). Asian-Australasian Journal of animal sciences.12:1736-1743.

Kannadhason S, Muthukumarappan K, Rosentrater K A 2009 Effects of ingredients and extrusion on aquafeeds containing DDGS and tapioca starch. Feed J Aquac Sci Nutr. 1:6-21.

Li M H, Robinson E H, Oberle D F, Lucas PM 2010 Effects of various corn distillers by-products on growth, feed efficiency, and body composition of channel catfish, Ictalurus punctatus. Aquac Nutr . 16:188-193.

Lim C, Yildirim-Aksoy M, Klesius P H 2009 Growth response and resistance to Edwardsiella ictaluri Channel Catfish, Ictalurus punctatus , fed diets containing distiller's dried grains with solubles. J World Aquac Soc. 40:182-193.

Shelby RA, Lim C, Yildrim-Aksoy M, Klesius PH 2008 Effects of distiller's grains with solubles-incorporated diets on growth, immune function and disease resistance in Nile tilapia (Oreochromis niloticus L.). Aquac Res. 39:1351-1353.

Trinh Thi Lan, Preston T R and Leng R A 2016 Feeding biochar or charcoal increased the growth rate of striped catfish (Pangasius hypophthalmus) and improved water quality. Livestock Research for Rural Development. Volume 28, Article #084. Retrieved from http://www.lrrd.org/lrrd28/5/lan28084.html