Evaluation of Dietary Lysophospholipids for Broilers Chickens and Laying Hens

Abstract

The studies aimed to increase nutrient utilization of broilers and laying hens by the use of lysophospholipid (LPL). This approach would be validated for poultry producers to minimize feed cost without retarding growth performance and laying productivity. Consequently, three experiments were conducted.

Experimental I. Effects of Lysophospholipid Supplementation to Lower Nutrient Diets on Growth Performance, Intestinal Morphology, and Blood Metabolites in Broiler Chickens The purpose of this research was to investigate the effects of dietary lysophospholipid (LPL) supplementation to diets lower in metabolizable energy (ME), crude protein including selected amino acids on growth performance, intestinal morphology, blood metabolites, inflammatory response, and carcass traits in broiler chickens. A total of 300 one-day-old male chicks (Ross 308) were assigned to 5 treatments, with 6 replications of 10 birds each in a completely randomized design. The 5 treatments were: positive control (PC) without LPL supplementation and adequate in all nutrients, negative control (NC) without LPL, and reduced 150 kcal/kg of ME and reduced 5% of total crude protein including Lys, Met, Thr, and Trp in a calculated amount relative to the PC, NC + 0.05% LPL (LPL05), NC + 0.10% LPL (LPL10), and NC + 0.15% LPL (LPL15). Broilers fed with NC diet had poorer growth performance and lighter relative weight of breast muscle compared with PC diet. Moreover, the NC birds were more susceptible to inflammation via modulating the secretions of tumor necrosis factor alpha (P = 0.011), interleukin-1 (P = 0.036) and increasing crypt depth of the jejunum and duodenum. However, feeding LPL linearly improved growth performance, feed conversion ratio, ether extract, and crude protein retention. The LPL supplementation on low-energy and nitrogenous diets showed significant lowering uric acid (P = 0.001) concentration. Furthermore, the inclusion of LPL to the NC diet could alleviate inflammation with tended to decrease crypt depth of the duodenum (P = 0.074) and decreased tumor necrosis factor alpha (P = 0.082). These improvements also influenced carcass composition, especially in relative weights of pancreas breast and leg muscle. Conversely, the LPL supplementation showed no significant effects on relative weights of immune organs, gizzard, and abdominal fat. Overall, LPL promotes growth performance, nutrient utilization, gut health, anti-inflammation, and muscle yields when applied to diets of broiler chickens with lower levels of energy, crude protein including selected amino acids.

Experimental II. Effects of Dietary Lysophospholipid Supplementation on Egg Production, Lipid Metabolism, Yolk Fatty Acid Deposition in Brown Egg-Laying Hens This study examined the effects of lysophospholipid (LPL) supplementation on egg production, egg quality, lipid metabolism, and yolk fatty acid deposition of brown egg-laying hens from 28 to 38 wks of age. A total of 420 Hy-Line W36 laying hens were allotted into five dietary treatments with six replicates and 14 hens in each treatment based on a completely randomized design. Hens were fed 0 (CON), 0.025 (LPL25), 0.05 (LPL50), 0.075 (LPL75), and 0.10% (LPL100) LPL in the five dietary treatments. There were no significant differences in laying performance and egg quality among treatments. However, increasing LPL level showed linear effects on hen-day production (P = 0.009) and egg mass (P = 0.005). The hens fed LPL75 was greater hen-day production (P < 0.05), egg mass (P < 0.01), and yolk color score (P < 0.05) than those fed CON. Linear increase in dark yolk pigmentation was also observed for laying hens fed dietary LPL (P = 0.038). No significant differences were observed in the retention of dry matter, crude protein and ash. However, crude fat tended to improve with increasing levels of LPL (P = 0.051). Cholesterol fractions, vitamins A and E concentrations were unaffected by dietary treatments at 33-wk of age. However, linear effects were observed for triglyceride (P = 0.020) and vitamin A (P = 0.022) concentrations at 38 wks of age. The LPL100 lowered cholesterol in the blood compared to CON. Furthermore, diets containing LPL100 had large percentage of C18:2n-6 and large ratio of polyunsaturated fatty acids to saturated fatty acids (SFA) than CON (P < 0.05). The supplementation of LPL also decreased the deposition percentage of SFA (linear effects

P = 0.003). Overall, the LPL can be used in laying hen diets to reduce cholesterol fractions and increase laying performance. Experimental III. Effects of Metabolizable Energy Levels and Lysophospholipid Supplementation on Productive Performance, Egg Quality, Nutrient Retention, and Blood Metabolites of Laying Hens This experiment was conducted to examine the effects of various metabolizable energy (ME) levels with or without lysophospholipid (LPL) supplementation on productive performance, egg quality, nutrient retention, and blood metabolites of laying hens. A total of 360 50-week-old Hy-Line W36 laying hens were subjected to 6 treatments in a 2 × 3 factorial arrangement with 2 levels of LPL (0 and 0.75 g/kg diet) and 3 levels of ME (2,670, 2,750, and 2,830 kcal/kg). Each treatment had 5 replications of 60 laying hens. No interactions were observed for all criteria of laying performance and egg quality. However, the main effect of the LPL significantly decreased egg weight and the cracked egg percentage (P < 0.05), as well as increased the yolk color score (P < 0.0001). The dietary ME levels did not improve nutrient retention of crude protein, but the LPL supplementation improved ether extract retention (P < 0.05) and a tendency for total ash (P = 0.083). Serum concentrations of α-tocopherol, alanine aminotransferase, triglyceride, and high-density lipoprotein were not affected regardless of the interactions or the main factors during both periods. However, the interactions between ME levels and LPL supplementation significantly improved glucose concentration at 58 weeks of age, which reached the highest value in hens fed ME at a 2,750 kcal/kg combination with 0.75 g/kg of LPL supplementation (P < 0.05). Furthermore, the LPL addition showed an improvement in retinol (P = 0.052) and a reduction in cholesterol concentrations (P = 0.075). Overall, the supplementation of LPL alone can possibly be used in lower-ME diets to eliminate losses of laying performance and increase yolk pigmentation through the improvement in nutrient utilization.