Comparative analysis of diet effects on growth performance and nutrient composition in house cricket, Acheta domestica as an alternative protein source in Thailand

Abstract

This comprehensive study investigated the diet’s impact on the growth and nutritional value of crickets (Acheta domesticus) in northern Thailand across five feed treatments. These included a commercial formula (CF21) with 21% protein content as a control, a novel cycling program of commercial formula (CF14) alternating between 21% and 14% protein feeds, and three new formulas (NF) with varied protein compositions (NF21 maintained a 21% protein diet, while NF17 and NF14 transitioned to 17% and 14% protein, respectively, after 21 days). Results revealed variations (p < 0.05) in production efficiency for 42-day-old crickets, including body weight, cricket production weight, and feed-to-body-weight conversion efficiency. NF21 displayed the highest average body weight for both sexes but the lowest total production weight. CF14 outperformed CF21 and the three new formulas. Despite trends in NF17 and NF14, their total weights slightly trailed CF14. Survival rates correlated with diet composition, with CF14 having the highest rate (71.08%), while subsequent groups experienced diminishing survival rates. Feed conversion ratio (FCR) analysis showed disparities, with NF21 recording the highest FCR value (3.34 ± 0.02) and CF14 recording the lowest (2.35 ± 0.01), highlighting different diet efficiencies. Economically, NF14 demonstrated cost-effectiveness at 25.92 ± 0.15 THB/kg (1 THB = 0.025 EUR), while CF14 emerged as the leader, achieving the highest net profit with a 51.51% cost reduction. The nutrient composition study revealed no significant impact on six values across all treatments. Overall, the majority of results favored CF14 as the preferred choice for achieving both cost-effectiveness and maximum yield.

Keywords:

• House crickets
• alternative protein
• feeding regimen
• dietary formulation
• nutrient composition

Reviewing Editor:

• Pedro Gonzalez-Redondo, Universidad de Sevilla, SPAIN

Subjects:

• Agriculture & environmental sciences
• agriculture
• agriculture and food
• entomology

1. Introduction

Beyond human consumption, crickets contribute to economic development through their highly nutritious profile. They are utilized as a component of animal feed in livestock production and hold potential for biomedical applications (Ferrazzano et al., 2023; Magara et al., 2020). This has resulted in income generation and job opportunities in cricket farming, processing, and the production of cricket-derived food products (Halloran et al., 2017). Additionally, the house cricket is gaining global popularity for its diverse applications in music and traditional play (Rai et al., 2023; van Huis, 2022; Yang et al., 2020).

Since 1997, cricket farming in Thailand has emerged as a global leader, capturing a 12% share in the Asia Pacific edible insect market since 2004 (Reverberi, 2020). In 2018, Livestock Data in Thailand commenced reporting cricket production, with the country’s initial total production at 103,093 kg from 118 farmers (Information and Communication Technology Center, 2018). By 2023, Livestock Data in Thailand reported a total cricket production of 2,044,950 kg involving 1,725 farmers. (Information and Communication Technology Center, 2023). These farms are scattered throughout the country, with a particularly strong presence in the northeastern and northern regions (Halloran et al., 2017; Hanboonsong et al., 2013).

Phitsanulok, situated in the lower north of Thailand, is well-suited for agriculture and fishing due to its abundant natural resources, freshwater, and year-round irrigation (Laorodphan et al., 2016; Urtgam et al., 2023; Yaemkong et al., 2023). According to the National Statistical Office of Thailand’s 2022 report on the Agriculture and Fisheries sector, Phitsanulok ranked sixth among 17 northern provinces and 23rd among the country’s 77 provinces in terms of registered agricultural households, totaling 103,994 households (National Statistical Office of Thailand, 2022). Despite these opportunities, a significant number of residents still face low incomes. In response to economic challenges in the region, cricket farming has emerged as a viable solution to address income issues. Farmers in Phitsanulok have adopted various approaches, ranging from small family-run businesses to larger ventures. From 2018 to 2023, the contribution of cricket farming in Phitsanulok amounted to 136 kg from two farmers out of a total production of 220,440 kg from 32 farmers (Information and Communication Technology Center, 2018, 2023).

Despite its profit potential, cricket farming faces challenges, particularly in managing significant production costs, with about 50% associated with feeding expenses. This highlights the need for cost-efficient strategies within the farm (Halloran et al., 2017; Hanboonsong et al., 2013). The escalating prices of raw materials, particularly protein sources, posed significant hurdles to the cost-effectiveness of cricket farming (Hanboonsong & Durst, 2020). Farmers in different areas and regions of the country have tried to find strategies to increase income by analyzing production costs, materials for rearing, and feed substitutes (Bawa et al., 2020; Kungwansupaphan, 2019; Sanyapoch et al., 2022).

From field visits at Kwanjai Farm Community Enterprise, it was observed that farmers in the study area raised house crickets, A. domesticus, utilizing commercial ready-to-eat feed with a 21% protein content. These farmers consistently maintained the protein level at 21% throughout one cycle in the production of this cricket species, which lasted for 42 days. Appropriate protein levels are known to be necessary for promoting favorable growth rates, reducing the duration of the developmental phase (Hanboonsong & Durst, 2020), and affecting nutritional value in crickets. Previous studies have indicated that diets with different protein content (16%–22%) or varied ingredients lead to diverse nutritional compositions, particularly in protein and fat, throughout the rearing process. The nutritional profile closely correlates with the diet’s protein content, showing that crickets exhibit high protein and low-fat content on a high-protein diet and lower protein content when provided with a lower protein source (Bawa et al., 2020; Oonincx et al., 2015; Riekkinen et al., 2022). Therefore, using a higher protein content in feed alone also translates to increased costs, making cricket feed a significant and ongoing variable cost in each production cycle. This practice also contributes to environmental issues and intensified ammonia odors (Bist et al., 2023; Fuah et al., 2015). Moreover, the previous study established the use of a 21% protein feed for crickets from hatching until they were 20 days old, followed by a mixed 14% and 21% protein feed until harvesting at 45 days old (Hanboonsong et al., 2013).

From the previous study reported above, we hypothesized that cricket protein requirements decrease in later rearing stages as the growth period increases. The feeding program was divided into two periods: the first, from the first to the 21st day (with higher protein demand), and the last, from the 22nd to the 42nd day (with lower protein requirements) compared with results from conventional farming. The challenge of this hypothesis stems from the interplay among the protein level in cricket feed, derived from diverse ingredients, its nutritional value, and the reduction in protein content as the insect matures. This interaction could have both positive and negative impacts on house cricket production and nutritional value. We anticipate discovering a new feeding program or formulation beneficial for raising crickets. The aim of this study, therefore, was formulated to carry out a comparative analysis, assessing the influence of the diet on the production efficiency and nutritional value of house crickets (A. domesticus) in the study area. The investigation included five feed treatment groups, each with varied protein levels or sources. The significance of this discovery lies in finding a new program or formula to replace the existing one, aiming to achieve cost-effectiveness, maximum yield, and maintain adequate nutritional value in crickets. The study results were expected to contribute to addressing poverty in local communities of Thailand by reducing costs and increasing farmers’ income in the future.

2. Materials and methods

2.1. Study site and population

This study was made possible through the significant support provided by the Kwanjai Farm Community Enterprise, located at 16°53’53.3"N 100°38’57.8"E in Wang Thong district, Phitsanulok province, Thailand. The farm’s management practices have been aligning with the Farm Thai Agricultural Standards for Good Agricultural Practices. The enterprise has exhibited efficiency in both the production and distribution of cricket products, focusing on cultivating crickets for sale at Makro, a prominent national department store, and in the general market.

The support from the farm played a crucial role in this study, facilitating the acquisition of A. domesticus cricket eggs for research purposes. In addition to providing essential rearing facilities, materials, equipment, and tools necessary for cricket rearing, the farm’s collaboration extended beyond mere resources, offering valuable insights into the practices employed during the initial stages of cricket rearing, spanning until the collection and sale period, which occurs after 42 days. According to information provided by the farm, a farming period of 42 days before harvesting is considered the most cost-effective approach.

This experiment utilized the quantity of cricket eggs in each container, adhering to both the prescribed program and feed formula outlined in the farm’s guidelines, while also incorporating a new program and formula. The initial population for the study consisted of ten ten-day-old egg blocks in each container, with each block weighing 500 g, resulting in a total weight of 5 kg per container. The egg blocks were composed of support material crafted from cocopeat. The daily feed amount was adjusted according to the age of the crickets, following the guidelines outlined in Table 1, which were also part of the farm’s recommended practices. This adjustment resulted in a total consumption of 31 kg.

Table 1. The daily feed quantity for crickets based on farming practices at Kwanjai Farm Community Enterprise, amounting to a total consumption of 31 kg.

Day	Feed quantity (g/day)	Day	Feed quantity (g/day)	Day	Feed quantity (g/day)
1–2	200.00	12–14	375.00	22–23	687.50
3–4	225.00	15–17	425.00	24–30	875.00
5–8	275.00	18–19	500.00	31–34	1,200.00
9–11	325.00	20–21	587.50	35–42	1,400.00

2.2. Components and nutritional content of the cricket feed utilized

The nutritional composition and ingredient specifications for five protein content variations, originating from two sources, were studied. The first group included two commercial formulas, ready-made cricket feed products with protein contents of 21% (trade name Erawan G1) and 14% (trade name Erawan G5) (Charoen Pokphand Foods (CPF) Pub Co., Ltd, Bangkok). Notably, Erawan G1 is specifically used as feed for crickets in the farm. Both formulas lack specific information about the quantities of ingredients used in their commercial formulations (Table 2).

Table 2. Ingredients, nutritional composition, and cost price of cricket feed formulated for five treatment groups at different protein contents on a dry matter basis.

Item	Protein contents (%)
	Commercial formula		New feed formula
	21	14	21	17	14
Ingredients
Corn meal (g)	NA	NA	494.00	290.00	238.00
Tapioca meal (g)	NA	NA	40.00	320.00	300.00
Rice bran (g)	NA	NA	75.00	60.00	100.00
Wheat bran (g)	NA	NA	0.00	0.00	140.00
Soybean meal (g)	NA	NA	340.00	274.00	160.00
Fish meal (g)	NA	NA	5.00	0.00	0.00
Calcium carbonate (g)	NA	NA	40.00	50.00	55.00
Salt (g)	NA	NA	3.00	3.00	4.00
Vitamin-mineral premix (g)	NA	NA	2.00	2.00	2.00
Mycotoxin adsorbents	NA	NA	1.00	1.00	1.00
Total (g)	1,000.00	1,000.00	1,000.00	1,000.00	1,000.00
Calculated chemical composition
Crude protein (%)	21.00	14.00	21.00	17.00	14.00
Crude fat (%)	3.00	2.00	3.00	3.00	3.00
Crude fiber (%)	5.00	7.00	4.10	4.00	4.50
Moisture content (%)	13.00	13.00	1.30	1.30	1.30
Available phosphorus, g/kg	NA	NA	7.00	7.00	5.00
Cost
Feed cost price (THB/kg)	20.00	17.00	14.18	13.17	12.33

Note: ‘NA’ is used to indicate a lack of information regarding commercial formulas, specifically in reference to a ready-made cricket feed from CPF. 1 THB = 0.025 EUR.

The second group consisted of three newly developed feed formulas, featuring protein contents of 21%, 17%, and 14%, with ingredient quantities expressed in grams per kilogram (g/kg). The vitamin-mineral premix provided per kilogram of the diet included: 5,200 IU of Vitamin A (trans-retinyl acetate), 1,040 IU of Vitamin D3 (cholecalciferol), 5.34 mg of Vitamin E (all-rac-tocopherol-acetate), 1.00 mg of Vitamin K3 (bisulphate menadione complex), 0.60 mg of Vitamin B1, 3.20 mg of Vitamin B2, 1.20 mg of Vitamin B6, 0.01 mg of Vitamin B12 (cyanocobalamin), 12.00 mg of nicotinic acid, 3.76 mg of pantothenic acid (D-calcium pantothenate), 0.50 mg of folic acid, 0.04 mg of biotin, 0.10 mg of selenium, 0.04 mg of cobalt, 0.20 mg of iodine, 32.00 mg of zinc, 16.00 mg of iron, 40.00 mg of manganese, and 4.00 mg of copper. Calculated chemical composition values were derived based on the analyzed nutrient values according to the National Research Council (1994). The nutritional composition of each cricket feed formula at 1,000 g is further detailed in Table 2.

At various protein levels, as indicated in Table 2, test feeds for each treatment comprised two commercial formulas (CF): a control group with 21% protein (CF21) and a novel program with 14% protein (CF14), involving cycling between 21% and 14% protein feeds within a commercial formula. Additionally, three new formulas (NF) with varied protein compositions were utilized. NF21 maintained a 21% protein diet, while NF17 and NF14 transitioned to 17% and 14% protein, respectively, after 21 days within a new formula.

2.3. Experimental design

The experimental design employed in this study followed a completely randomized design (CRD), where treatments were randomly assigned to 20 containers. The five feed treatment groups consisted of two commercial formulas: CF21 and CF14, and three new formulas: NF21, NF17 and NF14. Each feed treatment was administered to four containers, ensuring an equal probability for each container to receive any of the five protein formulas. This systematic approach played a crucial role in controlling potential variations, thereby enhancing the precision and reliability of the experimental results. The experimental design using the CRD method has certain limitations. The findings from 20 containers may not be fully representative of the results for the entire Community Enterprise group, given the diverse rearing environments in each household within the community. To mitigate this limitation, one household was strategically chosen. This approach allowed the study to concentrate on the singular factor of feed, which significantly influenced cricket production, under consistent conditions.

The daily feed quantity for crickets over the 42 days was established following the farming practices at Kwanjai Farm Community Enterprise, with each container requiring 31 kg of feed per production cycle. The procedures for each treatment group were explained as follows:

CF21: The crickets in this group received a continuous diet of commercial feed with a protein content of 21% over the 42-day experimental period. This group serves as a control group for comparison with other groups subjected to varied diets, representing the current feed formula employed in the comparative analysis of a new feeding program or three new diet formulas’ effects on the growth performance and nutrient composition of crickets.

CF14: This group was an experimental cohort that used two different commercial diet formulas with a protein content of 21% and 14%. The 21% protein diet remained consistent with that of CF21, while the 14% protein diet consisted of the following ingredients: fish meal and/or meat and bone meal; soybean meal, sunflower seed meal and/or coconut pulp; corn meal and/or broken rice; fine rice bran, oil-extracted rice bran and/or molasses; calcium carbonate and/or dicalcium phosphate; salt; vitamins; minerals; amino acids; and feed preservatives. The production factory has not disclosed the specific mix ratios. The 21% and 14% protein feeds were employed to nourish crickets during days 1–21 and days 22–42, respectively.

NF21: This group was furnished with a stable diet containing 21% protein, which had been formulated using the components outlined in Table 2. This diet remained consistent over the entire experimental period, from day one to day 42.

NF17: This group employed two formulated diet formulas, one with 21% protein and the other with 17% protein (as outlined in Table 2). The crickets were initially fed with a 21% protein diet for a duration of 21 days and then switched to a 17% protein diet for the final 21 days.

NF14: This group received two formulated diets, one with a 21% protein diet and the other with a 14% protein diet (as outlined in Table 2). The crickets were initially given a 21% protein diet for 21 days, after which they were switched to a 14% protein diet for the final 21 days.

2.4. Raising crickets

During the period from November 2022 to January 2023, house crickets were raised at Kwanjai Farm Community Enterprise as part of this study. Twenty containers, initially filled with 5 kg of cocopeat-made egg blocks, were prepared for the experiment. On average, for every 100 g, there were 1,126.50 ± 14.16 eggs observed across 30 repetitions. These smart board-made containers measured 120 cm in width, 240 cm in length, and 60 cm in height, and each was covered with a net to ensure the safety of the crickets and prevent escape. The experiment began on the first day, coinciding with egg hatching, and concluded after 42 days.

During the 42-day cricket rearing period, we implemented diets with varying protein content, categorized into five treatment groups as per the experimental design. In each treatment group, daily cricket feeding was conducted based on the specified weight of feed outlined in Table 1, corresponding to the crickets’ age. Additionally, 200 ml of water was provided daily, and the net amount of feed was consistently maintained in every container as outlined. Any supplementary feed remaining in the tray from previous days throughout the entire raising period was exhausted upon completion. Crickets were provided with daily water, and their feed and water were distributed across 4–5 trays. These trays had dimensions of either 23 cm in width, 31 cm in length, and 3 cm in height, or a diameter of 30 cm with a height of 3 cm. Stones in the water tray served as walking tracks. This routine, initiated at 7 a.m. from the nymphs’ hatching, continued throughout the 42-day data collection period. Furthermore, each container housed paper egg nests, serving as both habitat and potential shelter for the crickets.

2.5. Experimental data collection

Cricket body size and weight were assessed during two stages: the 21-day age and the 42-day age. The findings for the 21-day age were presented as an average for both sexes due to the inability to differentiate between genders at this stage. Subsequent measurements of body size and weight were conducted at the 42-day age, where the data underwent reassessment by categorizing crickets based on sex. Thirty crickets of each gender were individually weighed in every container. The decision to measure males and females separately stemmed from the necessity to comprehend potential variations in protein requirements specific to each gender. To uphold the precision of the study, an equal number of individuals from both genders were measured before computing averages. These measurements were then utilized to ascertain the total weight of crickets in each container.

Sixty crickets were collected from each container for body size, weight, and nutrition tests. The insect collection was performed through a simple random sampling method, utilizing baited traps made from translucent wide-mouth cylindrical bottles (Figure 1). The bottles had a capacity of 1,000 ml, a diameter of 9.19 cm, and a height of 19.39 cm. Each container was equipped with two traps, baited with 20 g of feed sourced from the daily diet, and left open for a 5-minute duration to attract insects. The captured insects were then immobilized using an ether solution. Subsequently, body size and weight data were collected by gently pouring the insects out of the trap until the desired number and/or sex of samples was attained. Traps might be repeated if the desired number of insect samples is not obtained according to the experimental objective. After the measurements, all crickets were returned to their original containers, except for nutrition tests, which required the sacrifice of the samples and were conducted following the scheduled feed test.

Figure 1. Demonstration of insect collection using translucent wide-mouth cylindrical bottle traps.

To calculate the survival rate of the crickets in each experimental group, the number of surviving crickets was determined. This was achieved by dividing the total weight of the production (g) by the average weight (g) of the crickets. This number of individuals was then divided by the initial number of eggs used in the experiment, and the result was multiplied by 100 to express the survival rate as a percentage. The survival rate was calculated based on the assumption that a 100 g egg block contained 1,126.50 ± 14.16 eggs. Furthermore, the feed conversion ratio (FCR) played a vital role in providing insights into the efficient use of resources in cricket farming throughout a 42-day period. FCR was determined by dividing the overall weight of the consumed feed by the total weight of the produced crickets, where cumulative feed represented the total consumption, and weight gain was calculated as the difference between final and initial weights.

The examination of moisture content, crude protein, crude fat, ash, and crude fiber adhered to the methodologies specified in AOAC (2016). Moisture content was gauged using the AquaLab Model 4TE from METER Group, Inc., USA (964.22). The Kjeldahl method was applied to evaluate crude protein (981.10), and the determination of crude fat was carried out through the Sohxlet method (948.15). The acid detergent fiber method was employed for determining crude fiber content (985.29), while total ash content was determined by ashing in a carbolite furnace (923.23). Additionally, the calculation of total carbohydrates involved subtracting other proximate parameters from 100%, following the methodology outlined by Reis et al. (2012). These analyses were performed at the Science Center, Faculty of Science and Technology, Pilbulsongkram Rajabhat University.

2.6. Data analysis

The data analysis was performed with the SPSS statistics program (Version 17.0; SPSS Inc., Chicago). The analysis employed the analysis of variance (ANOVA) method to assess differences between means within each treatment concerning body weight, body size, total weight of production, survival rate (%), feed conversion ratio, feed production cost, and nutrient composition. To identify significant distinctions among treatment groups, the least significant difference (LSD) was employed with a confidence level of 95%.

3. Results

The primary objective of this research was to develop an effective feeding program and formula for house crickets, A. domestica, that would maintain the nutritional value of the crickets while effectively reducing agricultural production costs. The rearing of house crickets in this study was conducted at Kwanjai Farm Community Enterprise in Wang Thong district, Phitsanulok province, Thailand, from November 2022 to January 2023. Previous information obtained from the farm revealed that, after 42 days of cricket rearing, the yield of crickets varied between 9 and 14 kg/container. The environmental conditions at the facility were characterized by an average temperature of 30.11 °C, and an average relative humidity of 68.43%. In the study comparing the impact of feed on the body weight of crickets raised for 21 days across five treatment groups, it was observed that crickets in all treatment groups exhibited statistically significant variations in body weight, with a significance level (p < 0.05). The crickets in NF21 were provided with a new formula containing 21% protein. They exhibited the highest body weight, averaging 54.65 ± 0.03 mg/individual, followed by treatment groups NF14, CF21, CF14, and NF17, respectively, with values of 46.93 ± 0.03, 43.83 ± 0.06, 39.75 ± 0.07, and 39.55 ± 0.08 mg/individual (Table 3).

Table 3. Impact of feed recipes and feeding programs on the production performance of crickets.

Item	Treatment group (Mean ± SE)					Sample size (n)
	CF21	CF14	NF21	NF17	NF14
At 21 days
Body weight (mg/ind)	43.83 ± 0.06^c	39.75 ± 0.07^d	54.65 ± 0.03^a	39.55 ± 0.08^e	46.93 ± 0.03^b	240
At 42 days
Body weight (g/ind)
Male	0.22 ± 0.00^d	0.24 ± 0.00^c	0.28 ± 0.00^a	0.26 ± 0.00^b	0.23 ± 0.00^c	120
Female	0.40 ± 0.00^e	0.42 ± 0.00^c	0.49 ± 0.00^a	0.43 ± 0.00^b	0.41 ± 0.00^d	120
Total mean	0.31 ± 0.01^d	0.33 ± 0.01^bc	0.38 ± 0.01^a	0.35 ± 0.01^b	0.32 ± 0.01 ^cd	240
Body size (cm/ind)
Male	1.87 ± 0.01^c	1.93 ± 0.01^b	1.98 ± 0.01^a	1.94 ± 0.01^b	1.90 ± 0.01^b	120
Female	2.13 ± 0.00^b	2.14 ± 0.00^b	2.15 ± 0.00^a	2.14 ± 0.01^b	2.13 ± 0.00^b	120
Total mean	2.00 ± 0.01^c	2.03 ± 0.01^b	2.06 ± 0.01^a	2.04 ± 0.01^b	2.02 ± 0.01^bc	240
Total weight of production (kg/container)	9.94 ± 0.06^d	13.21 ± 0.04^a	9.28 ± 0.05^e	10.42 ± 0.14^c	11.18 ± 0.06^b	4
Survival rate (%)	57.13 ± 0.35^b	71.08 ± 0.23^a	42.99 ± 0.22^e	48.31 ± 0.67^d	51.83 ± 0.30^c	4
Feed conversion ratio	3.12 ± 0.02^b	2.35 ± 0.01^e	3.34 ± 0.02^a	2.98 ± 0.04^c	2.77 ± 0.02^d	4
Feed cost price (THB/kg)	20.00	17.00	14.18	13.17	12.33	1
Feed production cost (THB/kg)	62.37 ± 0.38^a	30.24 ± 0.10^c	35.93 ± 0.18^b	29.71 ± 0.41^c	25.92 ± 0.15^e	4

Note: The mean values with different superscript letters in a row are significantly different at the 0.05 level. "ind" denotes "individual", and "n" represents the sample size in each treatment group, with each group comprising four observations. The average body weight of 1-day-old nymphs was 1.01 ± 0.06 mg (n = 30). The average egg count was 1,126.50 ± 14.16 eggs/100 grams (n = 30). 1 THB = 0.025 EUR.

The analysis of different diets within each treatment group on cricket body weight over a 42-day period revealed statistically significant differences in body weight based on the sex of the crickets (p < 0.05), indicating diverse impacts on growth and development between male and female crickets. Notably, treatment group NF21 consistently yielded the highest body weight for both genders, with males at 0.28 g/individual and females at 0.49 g/individual. These findings were consistent with the total mean weight data, highlighting NF21 as particularly effective in promoting the highest body weight (0.38 g/individual) compared to other diets (Table 3). Similarly, when examining cricket body size, individuals in the NF21 treatment group displayed the highest body size values compared to other treatments, both when calculated separately by gender and regardless of gender consideration, with statistically significant differences (p < 0.05). Male crickets in NF21 measured at 1.98 cm/individual, while females measured at 2.15 cm/individual. The total mean body size for NF21 was recorded at 2.06 cm/individual (Table 3).

From these results, it was evident that a novel program (CF14) and three new formulas (NF21, NF17, and NF14) could yield crickets with a weight and body size higher than or equivalent to a control group (CF21), with statistical significance (p < 0.05) (Table 3).

In the study of overall cricket production weight, the findings demonstrated that each of the treatment groups exhibited statistically significant differences in the total weight of cricket production in their containers (p < 0.05). The results of the total weight of production study using the developed formulas (NF14 and NF17) showed promise compared to the conventional cricket rearing feed formulas (CF21), with a statistically significant difference (p < 0.05). However, it is worth noting that this result is still lower than the result from CF14 at a statistically significant difference (p < 0.05). The treatment group that achieved the highest cricket production was CF14, which received a diet with 21% protein during the initial 21 days and 14% during the subsequent 21 days. This resulted in a total weight of 13.21 ± 0.04 kg/container. This was followed by NF14, NF17, CF21, and NF21, which had respective values of 11.18 ± 0.06, 10.42 ± 0.14, 9.94 ± 0.06, and 9.28 ± 0.05 kg/container (Table 3). The results of both the total weight of production and body weight in each treatment group were indicative of the cricket survival rates, which were measured over a 42-day period. The survival rates displayed a significant difference among the treatment groups (p < 0.05). CF14 achieved the highest cricket survival rate at 71.08%. Subsequently, treatment groups CF21, NF14, NF17, and NF21 obtained survival rates of 57.13%, 51.83%, 48.31%, and 42.99%, respectively (Table 3). In the evaluation of FCR values, it was observed that NF21 had the highest FCR value at 3.34 ± 0.02, whereas CF14 had the lowest FCR value at 2.35 ± 0.01. The FCR value also showed a significant difference among the treatment groups (p < 0.05) (Table 3).

Through the calculation of the cost of feed per 1 kg of cricket production, it was determined that each treatment group exhibited a value indicating a significant difference among the groups (p < 0.05) (Table 3). The result of this study revealed that NF14 had the lowest feed production cost, amounting to 25.92 ± 0.15 THB/kg. Consequently, when comparing the difference in feed investment between CF21 and CF14, an additional profit of 31.35–32.94 THB/kg, or an average of 32.13 THB/kg of cricket production, is observed. This equates to a 51.51% decrease in feed costs. Based on these results, the profit derived from an average reduction in costs, whether calculated in THB/kg or %/kg, was not found to be significantly different from NF17 (p < 0.05). However, it was significantly different from the other treatment groups (p < 0.05). Therefore, this result was compared with the total weight of production to determine the total net profit in the production cycle studied. It was found that in CF14, the difference in profit from reducing feed costs was the greatest, averaging 424.49 THB/production cycle, falling within the range of 415.96–434.76 THB. It was observed that in CF14, the difference in profit from reducing feed costs was the highest, averaging 424.49 THB per production cycle, falling within the range of 415.96–434.76 THB. The subsequent groups with notable net profit are treatment groups NF14 and NF17, while NF21 yields the least net profit in production, amounting to 245.26 THB per production cycle (Table 4).

Table 4. Profit and net profit derived from an average reduction in costs.

Item	Treatment group	Average of profit		Range of profit
		Mean	Std. Error	Minimum	Maximum
Profit derived from an average reduction in costs (THB/kg)	CF21	0.00^d	0.00	0.00	0.00
	CF14	32.13^b	0.36	31.35	32.94
	NF21	26.44^c	0.55	25.17	27.75
	NF17	32.65^b	0.14	32.25	32.86
	NF14	36.45^a	0.49	35.04	37.33
Profit derived from an average reduction in costs (%/kg)	CF21	0.00^d	0.00	0.00	0.00
	CF14	51.51^b	0.28	51.01	52.11
	NF21	42.38^c	0.63	41.00	43.91
	NF17	52.37^b	0.40	51.50	53.32
	NF14	58.43^a	0.45	57.09	59.07
Total weight of production (kg/container)	CF21	9.94^d	0.06	9.81	10.10
	CF14	13.21^a	0.04	13.10	13.30
	NF21	9.28^e	0.05	9.20	9.40
	NF17	10.42^c	0.15	10.19	10.80
	NF14	11.18^d	0.06	11.00	11.30
Net profit (THB/production cycle)	CF21	0.00^e	0.00	0.000	0.00
	CF14	424.49^a	4.73	415.96	434.76
	NF21	245.26^d	6.33	231.52	260.86
	NF17	340.35^c	5.40	328.67	353.47
	NF14	407.54^b	7.44	385.50	418.10

Note: The mean values with different superscript letters in a column are significantly different at the 0.05. The calculation conditions used feed expenses from CF21 as a reference value, given that it represents an actual expense currently utilized by the farm. The sample size in each treatment group was four (n = 4), with each group comprising four observations. 1 THB = 0.025 EUR.

The results of the analysis of nutrients in crickets in each treatment group, including moisture, protein, fat, carbohydrate, ash, and fiber, revealed no statistically significant differences in nutrient levels among all treatment groups at the 0.05 significance level. The average percentages for moisture, protein, and fat were 4.55%, 74.91%, and 6.80%, respectively. For carbohydrate, ash, and fiber, the corresponding average percentages were 8.91%, 4.84%, and 8.08% (Table 5).

Table 5. The nutrient composition data of cricket.

Treatment group	Average and standard error values for chemical properties (%)
	Moisture	Protein	Fat	Carbohydrate	Ash	Fiber
CF21	4.53 ± 0.03^a	74.47 ± 0.37^a	6.75 ± 0.02^a	9.47 ± 0.37^a	4.79 ± 0.009^a	8.10 ± 0.04^a
CF14	4.52 ± 0.07^a	74.26 ± 0.44^a	6.80 ± 0.04^a	9.63 ± 0.33^a	4.84 ± 0.05^a	8.07 ± 0.05^a
NF21	4.61 ± 0.01^a	75.45 ± 0.48^a	6.24 ± 0.02^a	8.85 ± 0.44^a	4.85 ± 0.08^a	8.06 ± 0.09^a
NF17	4.54 ± 0.01^a	75.56 ± 0.53^a	7.08 ± 0.02^a	7.91 ± 0.51^a	4.91 ± 0.02^a	8.10 ± 0.06^a
NF14	4.57 ± 0.03^a	74.80 ± 0.44^a	7.12 ± 0.04^a	8.67 ± 0.43^a	4.84 ± 0.09^a	8.08 ± 0.08^a
Average	4.55 ± 0.02	74.91 ± 0.22	6.80 ± 0.07	8.91 ± 0.22	4.84 ± 0.03	8.08 ± 0.03

Note: The mean values with different superscript letters in a column are significantly different at the 0.05. Each treatment group consists of four observations (n = 4).

4. Discussion

The main goal of this study was to devise an effective feeding schedule and formulation for house crickets (A. domestica) with the aim of retaining their nutritional value while concurrently reducing agricultural production costs. The study’s findings revealed that the optimal feeding program for the crickets included providing feed with a protein level of 21% for the initial 21 days, followed by a transition to 14%, ligning with the findings of Phesatcha et al. (2022). Their research examined the impact of local feed on production performance and nutritional composition in crickets. They found that cricket species thrived on a diet with protein ranging from 14% to 21%. This corresponds to a study by Miech et al. (2017), which established 18.4% as the minimum protein level for cricket growth. However, this differed from the study by Orinda et al. (2017), which suggested that crickets perform well with a diet containing 20% to 30% protein. Reducing the protein level from 21% to 14% in later stages can effectively cut feed costs for cricket rearing. Furthermore, several studies (Hang et al., 2020; Lam et al., 2022; Phesatcha et al., 2022) indicated that utilizing locally available raw materials like crushed cassava leaves and ground mulberry leaves as cricket feed could significantly cut transportation costs. Replacing soybean meal with these leaves in cricket feed formulations was deemed cost-effective, resulting in a minimum 18% reduction in production costs compared to feeds containing 30% soybean meal (21.0% protein) (Phesatcha et al., 2022). In addition, over a 28-day period, crickets exhibited a 14% increase in total biomass yield when provided unrestricted access to fresh cassava leaves in conjunction with commercial feed (Hang et al., 2020).

The difference in size between male and female crickets across the new diets (NF21, NF17, and NF14) compared to the control diet (CF21) suggested potential issues with the feed provided in the study, including inappropriate rearing density in containers. Factors such as feed quality, quantity, and high density may have contributed to cannibalism, ultimately affecting the poor quality of the crickets (Mahavidanage et al., 2023). This could explain the variations in survival rates observed in this study, where CF14 had a higher survival rate (71.08%) than CF21 (57.13%), while all new formulas showed lower survival rates (ranging from 42.99% to 51.83%). Furthermore, the low survival rate could be attributed to the low-fat content of the feed used for rearing. Previous research reports have described how diets for house crickets (A. domesticus) containing plants as a substitute for high levels of animal protein tended to have reduced fat content, which could result in survival rates of house crickets being less than 50% (Vaga et al., 2021).

Additionally, despite the developed formula resulting in a lower total weight of production compared to CF14, which uses a ready-made formula, this experiment suggests that the developed feed formula can still yield a higher total production weight than the currently employed CF21 in agriculture. Therefore, for those looking to reduce dependence on pre-made feed, agriculture can opt for the formulas in NF17 and NF14, as they offer higher yields and lower prices. This choice has the potential to increase the income of cricket farmers. However, this study also revealed that the total weight of cricket production and the rate of feed conversion to body weight in the group receiving commercial feed (CF14; 14% protein) exhibited significantly better values (p < 0.05) when compared to the group receiving the experimental diet (NF14; 14% protein). This difference could be attributed to variations in the types and sources of raw materials used in the respective recipes. This finding aligns with previous studies indicating that a minimum protein content of 14% is sufficient for the growth of Gryllus bimaculatus crickets (Phesatcha et al., 2022).

The chemical quality analysis of crickets revealed that protein was the predominant main component, averaging 74.91%, followed by carbohydrate, fiber, fat, and ash, respectively. The nutrient composition levels identified in the crickets in this study align with previous research, where protein ranged from 59.70% to 75.00%, carbohydrate from 1.13% to 11.90%, fiber from 4.60% to 8.68%, fat from 8.00% to 23.80%, and ash from 3.79% to 5.40% (Amarender et al., 2020; Jino et al., 2021; Promkhan et al., 2020; Sihamala et al., 2018; Udomsil et al., 2019). This result confirms that adjusting the protein proportions in this experiment did not affect the nutritional benefits for consumers. However, it had a positive effect on increasing the income of farmers, especially when adjusting the feeding program according to CF14.

The variation in net cricket production across treatments may be attributed to differing protein levels and sources. The new feed formula prioritizes cost reduction by primarily using the more affordable soybean meal as the main protein source, thereby minimizing reliance on costlier fish meal. Consequently, the proportion of fish meal is either minimal (NF21) or absent (NF17 and NF14) in the new formulations. This shift in protein sources may impact cricket body size differently. This aligns with prior research indicating that house cricket growth can be influenced by different diets, particularly those varying in protein content. For instance, crickets fed a diet containing 22% protein exhibited a 9% increase in mean body weight and length compared to those fed a diet with only 16% protein (Bawa et al., 2020). However, despite increasing the proportion of plant substitutes, such as corn meal, tapioca meal, rice bran, and wheat bran, there is no discernible difference in the nutritional value of crickets among the five treatment groups. This suggests that the formulated blends maintain consistent nutritional profiles across various protein levels and sources. According to various studies (Hang et al., 2020; Phesatcha et al., 2022), substituting cassava leaves and ground mulberry leaves for soybean meal in cricket feed formulations not only reduces feed costs but also introduces a slight variation in the nutritional value of crickets (G. bimaculatus). In the absence of fish meat ingredients, crickets raised on plant leaves exhibit protein levels ranging from 76.20% to 73.40%, and fat levels ranging from 14.8% to 12.5%. Notably, there are no discernible differences in ash, fiber, and carbohydrate levels (Phesatcha et al., 2022).

5. Conclusions

In summary, this study aimed to assess the impact of diet on the production efficiency and nutritional value of house crickets. Significant variations were observed in the 21-day body weight comparison, but no differences were found in the 42-day analysis among treatment groups (0.31–0.38 g/individual). Notably, modifying the feeding program could significantly reduce production costs by up to 32.13 THB/kg, leading to a substantial 51.51% decrease in feed costs. Despite the new formula yielding a lower total production weight than the commercial formula CF14, it has the potential to outperform the currently employed CF21. For farmers aiming to decrease reliance on pre-made feed, the experimental feed recipes of NF14 offer higher yields and lower costs, potentially enhancing income. While NF21 exhibited the highest FCR value, CF14 demonstrated the lowest, contributing to the highest profit (424.49 THB/production cycle). Nutrient analysis revealed no significant differences among treatment groups. In conclusion, adjusting the feeding program, especially by reducing protein levels after 21 days, holds the potential to enhance cricket production, reduce costs, and increase profitability. This underscores the importance of tailoring the feeding program and dietary formula to specific production objectives, whether focusing on individual cricket size (NF21) or overall production yield (CF14).

Although all new formulas exhibited lower survival rates, total weight of production from NF17 and NF14 showed higher yields and lower feed costs compared to CF21. Despite slightly lower yields of NF21 compared to CF21, its reduced feed costs led to increased profit margins. Hence, all formulas can replace CF21, and the study successfully met its objectives.

However, further research is necessary to refine findings, particularly regarding the appropriate amount of feed used to feed crickets in order to increase the survival rate. Ensuring sufficient daily feed intake is critical to prevent cannibalism and address potential impacts on FCR. Additionally, optimizing the density of crickets in each container according to its size is important. These measures will directly contribute to increasing Thailand’s cricket production in the future.

Ethical statement

Ethical approval for this study was obtained from the Ethical Committee of Pibulsongkram Rajabhat University (PSRU-(AG)-2022-001).

Authors’ contributions

Conceptualization, S.Y. and T.J.; methodology, S.Y., T.I., N.R. and T.J.; validation, formal analysis and investigation S.Y., T.I., N.R. and T.J.; resources, S.Y. and T.J.; data curation, S.Y. and T.J.; writing—original draft preparation, S.Y., T.I., N.R. and T.J.; writing—review and editing, S.Y., N.R. and T.J.; visualization, supervision and project administration, S.Y. and T.J.; funding acquisition S.Y. and T.J. All authors have read and agreed to the published version of the manuscript.

Acknowledgments

We extend our sincere appreciation to the owner of Kwanjai Farm Community Enterprise in Wang Thong district, Phitsanulok province, Thailand, for their generous support in providing both financial assistance and wreath samples for this study, along with their dedicated officers. Special appreciation goes to the technicians from Pibulsongkram Rajabhat University for their invaluable support in completing this research.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author, [T.J.], upon reasonable request.

Additional information

Funding

This work was supported by the Fundamental Fund for fiscal year 2024 (Grant nos. RDI-1-67-03 and RDI-1-67-09) and the Research Fund of the Research and Development Institute at the Pibulsongkram Rajabhat University under Grant no. RDI-2–65-63.

Notes on contributors

Suphawadee Yaemkong

Suphawadee Yaemkong, with a Doctor of Philosophy degree in Animal Science from Kasetsart University, currently serves as an Associate Professor and faculty member at the Faculty of Food and Agricultural Technology, Pibulsongkram Rajabhat University, located in Phitsanulok, Thailand. Her research interests and expertise predominantly revolve around animal research, specifically in animal production and socio-economic aspects within the broader field of animal science.

Tossaporn Incharoen

Tossaporn Incharoen is an Assistant Professor and a member of the Faculty of Agriculture Natural Resources and Environment at Naresuan University, located in Phitsanulok, Thailand. He earned his Ph.D. in Animal Science from Ehime University, Japan. His research expertise focuses on animal production and animal nutrition within the field of Animal Science.

Nontaporn Rattanachak

Nontaporn Rattanachak is a Ph.D. student in the Biomedical Sciences Program at the Faculty of Allied Health Sciences, Naresuan University. Additionally, she holds a faculty position at the Faculty of Science and Technology at Pibulsongkram Rajabhat University, located in Phitsanulok, Thailand. Her primary research interests and expertise focus on alternative agents derived from natural products, sustainable biodiversity utilization, and the study of genetic diversity within living organisms.

Touchkanin Jongjitvimol

Touchkanin Jongjitvimol is an Associate Professor and also a faculty member at the Faculty of Science and Technology at Pibulsongkram Rajabhat University, located in Phitsanulok, Thailand. He completed his Ph.D. in Biological Sciences at Naresuan University. His research interests include biodiversity conservation, sustainable biodiversity utilization, and genetic diversity within living organisms.