Evaluation of Dietary Supplementation with Talinum Triangulare Extract on Egg Quality and Quantity, Haematology, and Serum Biochemistryin Pullets

Abstract

Poultry products are among the most valuable sources of animal protein, and offer a means of meeting the animal protein needs of the population. Compounded poultry feed, physical inactivity of the birds due to overcrowding and certain unhealthy habits like pecking are major setbacks to intensive poultry production. The result is high cost and high cholesterol content of products. The later has been a cause for concern to health-conscious consumers. High blood cholesterol levels have been associated with chronic diseases of high public health importance such as atherosclerosis, stroke, and obesity. Healthy dieting has been found to reduce the incidence, morbidity and mortality associated with these diseases. Plant based food sources generally contain lower levels of cholesterol and are known to promote cholesterol excretion from the body. Talinum traingulare (TT) is a highly nutritive vegetable associated with favourable blood lipid profile in humans and broilers. However, there is paucity of information in available literature on its use on pullets. The aim of the study was to evaluate the use of TT as a nutraceutical to improve the quantity and quality of egg produced. The Specific objectives of the study were to evaluate: (i) the nutrient and phytochemical components of TT, (ii) the effects of supplementation of pullet diets with varied forms and doses of TT extract on egg production, characteristics, and cholesterol content and (iii) the effects of supplementation of pullet diets with varied forms and doses of TT exract on haematology and serum biochemistry of the pullets. The study adopted the experimental design. Talinum triangulare used for the study was sourced from Nsukka and identified by a plant taxonomist. Dried and freshly harvested samples of TT were used for the study. The plant was harvested, washed, and drained and (for the dried sample) was further dried under shade and pulverized. Extraction was done using cold maceration method with water over a period of 48 hours. In experiments one and two extracts for the study were subjected to quantitative nutrient analyses and qualitative phytochemical analyses following standard procedures. The animal study was in two phases – pullet supplementation (experiment three), and layer supplementation (experiment four). For experiment three, 90 chick pullets were randomly assigned into three groups (PA, PB, and PC) of 30 pullets each. Pullets in PA were given 1000 mg of the dried extract of TT/L of water; those in PB were given 1000 mg of the fresh extract of TT/L of water while those in PC were the unsupplemented control. Haematology and serum biochemistry were evaluated at two months interval within the six months of supplementation. In Experiment four, 210 laying birds were randomly assigned into seven groups (LA1, LA2, LA3, LB1, LB2, LB3 and LC) of 30 layers each. The TT extracts were given at 62.5, 250, and 1000 mg/l doses in dried form for LA1 LA2, and LA3 and fresh form for LB1, LB2, and LB3, respectively. Layers in the LC group served as unspplemented control. The egg quality and quantity, cholesterol content, haematology, and serum biochemistry of the birds were determined using standard procedures at two months interval during the 12 months of supplementation. Data generated from the study were subjected to one way analyses of variance (ANOVA) and variant means were separated using the Least Significant Difference (LSD) method. Significance was accepted at P < 0.05. The proximate composition of the TT extract were 21.96% protein, 28.09% ash, 17.38% crude fibre, 26.37% carbohydrate, 1.66% fat, 4.54% moisture and 208.27 kcal/kg energy. The mineral constituents (mg/100 g TT) were Calcium (856.53), Magnesium (1076.38), Iron (42.11), Potassium (6063.66), Sodium (39.78), Phosphorus (241.24), Zinc (10.67), and Copper (0.96). The qualitative phytochemical constituents were alkaloids, flavonoids, saponins, tannins, and glycosides. Hen-Day-Rate (HDR) of egg production revealed that birds in LA (LA1, LA2, and LA3) groups laid significantly (p < 0.05) more eggs than birds in LB groups (LB1, LB2, and LB3), and the control groups (LC). The total cholesterol (TChol) and low density lipoprotein cholesterol (LDL-C) of the eggs from layers in groups LA2 and LA3 were significantly (p < 0.05) lower than the untreated group especially by the 2nd, 4th, and 6th months of lay. The egg high density lipoprotein cholesterol (HDL-C) of the LA2, LA3, LB2, and LB3, were significantly (p < 0.05) higher than those of other supplemented groups and the control especially by the 4th, and 8th months of lay. The packed cell volume, red blood cell count, haemoglobin concentration, total and differential leukocyte counts as well as serum alanine aminotransferase and aspartate aminotransferase and total protein activities did not differ significantly (p > 0.05) in all the groups. The serum Tchol and LDL-C of groups LA2 and LA3 were significantly (p < 0.05) lower than those of other groups. The serum HDL-C of LA2 and LA3 were significantly (p < 0.05) higher than the control at 4th month of lay. Dietary supplementation with TT had no significant impact on haematology and liver enzymes; and had no adverse effect on health and production status of treated pullets. Specific egg-laying production parameters like hen day rate of production, Haugh Unit and Yolk Index increased following treatment of TT. Supplementation with TT reduced the concentration of LDL-C and increased HDL-C in the sera of treated pullets and in the eggs they laid. There was a significant increase in triacylglycerol level of over 600 per cent which occurred with the chick - pullets at the fourth month of life and was sustained in the laying birds till the end of the experiment (12th month of lay). Almost in all cases the dried sample had advantage over the freshly harvested sample and the high dose over the medium and low doses in that order. Aqueous extract from dried and freshly harvested Talinum triangulare (waterleaf) plant showed high potential of nutritional and phytochemical relevance and supports possible medicinal and dietary application in pullets. Use of TT extract for the prevention and treatment of CVD in poultry and production of designer – eggs low in cholesterol for human consumption is proposed based on the outcome of this study.