Effects of Dietary Supplementation of Essential Oils, Lysozyme, and Vitamins' Blend on Layer Hen Performance, Viral Vaccinal Response, and Egg Quality Characteristics

Maintaining respiratory tract health is crucial for layers, impacting gut health, laying performance, and egg quality. Viral diseases and standard vaccinations can compromise tracheal epithelium function, leading to oxidative stress. This study assessed the impact of a blend of feed additives, predominantly lysozyme (L), essential oils (EO), and vitamins (VIT) (referred to as L + EO + VIT), on young layers during an oral vaccination schedule. The supplementation significantly enhanced antibody titers for Newcastle Disease Virus (NDV) and Infectious Bronchitis Virus (IBV) after vaccination, trachea functionality and intestinal health in the jejunum, increased egg production, and exhibited a trend toward higher egg weight. Although feed intake showed no significant difference, egg quality remained consistent across experimental groups. Moreover, L + EO + VIT supplementation elevated total phenolic content in eggs, improving oxidative stability in both fresh and stored eggs, particularly under iron-induced oxidation. Notably, it substantially reduced yolk lipid peroxidation and albumen protein carbonyls. In conclusion, water supplementation with L + EO + VIT may enhance humoral immune response to IBV and NDV, positively impacting hen productivity. These findings indicate improved tracheal function and enhanced oxidative stability, emphasizing the potential of this blend in promoting overall health and performance in layers.

Effects of Dietary 1,8-Cineole Supplementation on Growth Performance, Antioxidant Capacity, Immunity, and Intestine Health of Broilers

This study was conducted to investigate the effects of 1,8-cineole on antioxidant capacity, immunity, and intestinal health of broilers. A total of 540 1-day-old Arbor Acres (AA) male broilers were randomly divided into five treatments with six replicates per treatment, and 18 broilers per replicate for 42 days. Dietary treatments were a corn−soybean meal basal diet supplemented with 0, and 10, 20, 30, and 40 mg/kg 1,8-cineole, respectively. Dietary supplementation with 20~30 mg/kg of 1,8-cineole increased the ADG from d 22 to 42 and d 1 to 42 (p < 0.05), and decreased the FCR (p < 0.05). Dietary supplementation of 10~40 mg/kg of 1,8-cineole increased total antioxidant capacity (TAOC) in serum (p < 0.05), and decreased malondialdehyde (MDA) level in the liver on day 21 (p < 0.05). The supplementation of 20~30 mg/kg of 1,8-cineole increased the activity of total superoxide dismutase (T-SOD) in the serum and liver and TAOC in the serum and the liver (p < 0.05), and decreased the level of MDA in the serum and the liver (p < 0.05) on day 42. Dietary supplementation with 20~30 mg/kg of 1,8-cineole increased serum immunoglobulin A, immunoglobulin G, and immunoglobulin M contents on day 21 (p < 0.05). On day 21, dietary supplementation of 20~30 mg/kg of 1,8-cineole increased the VH and VH/CD (p < 0.05) in the jejunum and ileum. The supplementation of 20~30 mg/kg of 1,8-cineole increased the content of secretory immunoglobulin A in the duodenum and ileum mucosa on d 42 (p < 0.05). In conclusion, dietary supplementation of 1,8-cineole improves the growth performance of broilers by enhancing antioxidant capacity, immunity, and intestinal morphology.

Evaluation of a Salmonella Enteritidis vaccine and related ELISA for respective induction and assessment of acquired immunity to the vaccine and/or Echinacea purpurea in Awassi Ewes

The aim of this study was to evaluate an experimental Salmonella Enteritidis (SE) bacterin and an indirect ELISA system to assess quantitatively the acquired immunity in Awassi ewes to the vaccine and/or Echinacea purpurea (EP) dried roots. Four treatments of the ewes were included in the experimental design, with 6 ewes/treatment. The first treatment (T1) had the controls that were non-vaccinated and non-treated with EP. The T2 ewes were only treated with EP. The T3 and T4 ewes were vaccinated at D1 (initiation of trial) and D10, while the T4 ewes were additionally administered the EP dried roots. Blood was collected from the jugular vein of all ewes at D1, D10, D21 and D45. The construction of the vaccine and the ELISA are detailed within the manuscript. The ELISA was able to detect quantitatively the significant acquired primary and secondary immunity to the vaccine in T3 and T4 ewes, compared to their low level of background immunities at initiation of the experiment (p<0.05). In addition, the ELISA detected the absence of seroconversion at all blood sampling times (p>0.05) in T1 control ewes, and in the T2 ewes that were given only the (EP) (p>0.05). Moreover, the ELISA was able to uncover the significant seroconversion of secondary immune response in T4 ewes at D21 compared to that at D10 (p<0.05), and the absence of significant seroconversion of secondary response in T3 ewes. This is the first work in literature that reports the need to supplement the vaccination by the experimental SE bacterin with daily oral intake of 250mg of EP-dried roots, effective the first vaccination day and up to 21 days, for obtaining a statistically significant seroconversion.

Control of eight predominant Eimeria spp. involved in economic coccidiosis of broiler chicken by a chemically characterized essential oil

AIM

To control eight most predominant Eimeria spp. involved in the economic disease of coccidiosis in broiler chicken, by a chemically characterized essential oil of eucalyptus and peppermint.

METHODS AND RESULTS

The experimental design consisted of 160 day-old-broiler chicks, divided into four equal groups (G1 , G2 , G3 and G4 ), with 40 birds per group. Each group was divided into four equal subgroups. Birds in G1 were deprived of essential oil treatment and of Eimeria challenge. Birds in G2 were unchallenged, and administered the essential oil in drinking water at 0.69 ml kg(-1) body weight. Birds in G3 were untreated with essential oil, and each of its four subgroups was challenged at a different age (14, 21, 28 and 35 days). Birds in G4 were treated with essential oil, and challenged in the same manner as for G3 . Equal number of birds from all subgroups (n = 10) were sacrificed at the sixth day after the time allocated for each challenge. The 6 day incubation period post challenge resulted in respective mean per cent weight increase in G2 and G1 birds equivalent to 57.8 and 53.1% (P < 0.05). In addition, the essential oil improved the per cent weight increase in challenged birds (54.6%) compared to the challenged-untreated birds (18.6%) (P < 0.05). The mean feed conversion, mortality, intestinal lesion scores and oocyst counts were significantly reduced in the challenged-treated birds compared to the challenged-untreated birds (P < 0.05).

CONCLUSIONS

The results support the hypothesis of using the essential oils of eucalyptus and peppermint to control the most prevalent Eimeria spp. involved in coccidiosis of broiler chicken, helping in improvement of their production, alleviation of lesions and reduction in intestinal oocyst counts.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides information about the possibility of using this blend of essential oil as a coccidiostat for the protection of broiler chickens against the prevalent eight Eimeria spp. of coccidiosis.