Effect of dietary folic acid enrichment on biochemical parameters and sensory evaluation in kadaknath birds

Introduction

The Indian poultry sector is among the most rapidly expanding agricultural industries and plays a important role in the nation's economic development. India currently holds the second position globally in egg production. During the financial year 2024-2025, egg output recorded a growth of 4.44% compared to the preceding year [1] . Eggs are economical and highly nutritious, making them an ideal vehicle for the delivery of functional nutrients. In recent years, designer eggs developed through the nutritional modification of laying hen diets have attracted considerable attention, particularly among health-conscious consumers [11] . Folic acid plays a vital role in numerous physiological functions, including cell division, tissue growth and cellular repair [2] . A folic acid-rich diet is essential not only for general health but also for preventing various conditions such as cleft lip and palate, neural tube defects, autism spectrum disorders, megaloblastic anaemia and certain cancers [3] . The ICMR-NIN sets the RDA (Recommended Dietary Allowances) of folic acid for Indians. For adult male it is 300 µg RDA and 250 µg EAR (Estimated Average Requirements). For adult female it is 220 µ and 180 µ EAR and for pregnant women is 400 µg RDA [10] . Kadaknath is a popular local breed in Dhar and Jhabua district of Madhya Pradesh, India, famous for its black meat, disease resistance and adaptability. The meat of kadaknath breed contains a high percentage (25.47%) of protein and have appreciable degree of resistance to diseases compared with other exotic breeds of fowl. Hence, the present study was undertaken to evaluate the effect of dietary folic acid supplementation on performance, egg quality, egg folate content and blood parameters in kadaknath laying hens [13] .

Materials and Methods

The experiment was conducted at the Poultry Farm, All India Coordinated Research Project (AICRP) on Poultry Breeding, NDVSU, Jabalpur, Madhya Pradesh, for a period of six months. A total of 120 kadaknath laying hens of 25 weeks of age were randomly allocated to five treatment groups with three replicates of eight birds each. The dietary treatments consisted of a basal layer ration (16% CP, 2600 kcal ME/kg) supplemented with folic acid at 4 mg/kg (T 0 ), 8 mg/kg (T 1 ), 16 mg/kg (T 2 ), 32 mg/kg (T 3 ) and 64 mg/kg (T 4 ). All diets were isocaloric and isonitrogenous and formulated as per ICAR (2013) standards [9] . Biochemical parameters (AST, ALT and creatinine). Sensory evaluation of boiled eggs was conducted using a nine-point hedonic scale. Statistical analysis was carried out using analysis of variance (ANOVA) under completely randomized design and treatment means were compared using Duncan's Multiple Range Test [4,12] .

Rearing of Kadaknath birds:

A fortnight before the start of the experiment, a layer shed housing facility was properly cleaned, disinfected with phenyl, white-washed and dried up. The weighed quantity of the experimental ration was offered daily in each pan as per the treatment group. Waterers were washed daily and clean drinking water was provided. All management factors were kept identical for all treatment groups. The kadaknath layer birds were reared up to 12 weeks of age for the collection of data.

Experimental design and distribution of birds:

A total number of 120 Kadaknath birds of 25 weeks old were selected and procured from the Poultry farm, AICRP on Poultry Breeding, Department of Poultry Science, College of Veterinary Science and Animal Husbandry, Jabalpur. For this research, 120 Kadaknath laying hens were used. There were 5 treatment groups with 3 replicates, each with 8 birds. The house was completely cleaned and disinfected. It was then kept empty for three days. Birds were housed in a cage housing system, with each bird having its own cage for the experimental period of 12 weeks. The necessary feeding and watering arrangements were carried out in accordance with the ICAR-2013 feeding standard [9] . Kadaknath were fed a diet (ME-2600 Kcal/kg, CP-16%) between 25 and 36 weeks of age. Throughout the trial, all of the meals given to the various treatment groups were isocaloric and isonitrogenous.

Biochemical parameter: Blood samples were collected from each bird in plain vacutainers, without the addition of any anticoagulants. Serum was then separated by centrifugation at 3,000 rpm for 5 minutes. The resulting serum was carefully transferred into labelled sterilized Eppendorf vials. The serum samples were subsequently analyzed for various biochemical parameters using a semiautomatic biochemical analyzer (Erba Mannheim) and the corresponding commercial assay kits. Following biochemical parameters were estimated by using commercial kits: Aspartate transaminase (AST) (IU/L) and alanine transaminase (ALT) (IU/L), Creatinine (mg/dl), Calcium (mg/dl) and Phosphorous (mg/dl).

Sensory evaluation of eggs:

A trained sensory panel of seven assessors conducted a descriptive evaluation of the characteristics of boiled eggs. Sensory attributes, including flavour and overall acceptability were evaluated using a 9point structured scale (1 = lowest intensity, 9 = highest) [6] . The eggs were boiled for 12 minutes, cooled, peeled and served immediately for evaluation. To minimize bias, the samples were presented in a randomized order for evaluation. The present findings are in agreement with earlier reports [7] . demonstrated that dietary folic acid supplementation significantly increased plasma folate concentration without adversely affecting other blood biochemical parameters, indicating efficient absorption and safe metabolism of folic acid [8] . also reported that higher levels of folic acid and vitamin B12 did not cause any adverse biochemical changes, further supporting the safety of folic acid supplementation [5] . observed increased serum creatinine, calcium and phosphorus levels when folic acid was supplemented along with vitamin C, suggesting that combined supplementation may enhance metabolic activity. However, in the present study, folic acid alone did not markedly alter creatinine or mineral levels, which may be attributed to differences in bird type, age and dietary combinations. T 3 and the control group were comparable and fell within the "liked moderately" category. Eggs from T 1 were slightly less preferred, whereas T 4 showed the lowest overall acceptability (5.87±0.47), suggesting reduced consumer appeal at higher folic acid levels. Overall, the results demonstrated that dietary folic acid enrichment had a clear influence on sensory attributes of Kadaknath eggs. Moderate folic acid supplementation, particularly in T 2 , improved flavour, yolk colour and overall acceptability, followed by T 3 , T 1 , T 0 , while excessive supplementation (T 4 ) appeared to adversely affect sensory quality.

Results and Discussion

Biochemical parameters

Sensory evaluation

Conclusion

Dietary folic acid supplementation significantly increased plasma folate concentration without adversely affecting other blood biochemical parameters, indicating efficient absorption and safe metabolism of folic acid. Folic acid supplementation can be recommended as a nutritional strategy for producing functional eggs from indigenous poultry and moderate folic acid supplementation, particularly in T 2 , improved flavour, yolk colour and overall acceptability as compared to T 3 , T 1 , T 0 and T 4 .

Acknowledgement

AcknowledgmentWe express my sincere gratitude to my Principle Investigator of Poultry farm, AICRP on Poultry Breeding, Department of Poultry Science, College of Veterinary Science and Animal Husbandry, Jabalpur for providing me with the opportunity to undertake this research work.

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