Effect of Fermented Ginkgo biloba and Camelia sinensis-Based Probiotics on Growth Performance, Immunity and Caecal Microbiology in Broilers

Effects of Micellar Quercetin Supplementation on Growth Performance, Nutrient Digestibility, Fecal Microbiota, Meat Quality, and Physiological Status in Broiler Chickens

This study investigated the impacts of micellar quercetin (MQ) supplementation on growth performance, meat stability, excreta gas emissions, and physiological status. During a 35-day trial, 640 Ross 308 broilers were utilized. These birds were one day old, with an average initial body weight of 43.34 ± 1.43 g. They were randomly distributed across four experimental diets, each consisting of 10 replicate pens with 16 chicks per pen. The diets included the following: control (CON) with 0% micellar quercetin (MQ), TRT1 with 0.025% MQ, TRT2 with 0.050% MQ, and TRT3 with 0.100% MQ. The results indicate that broilers fed diets with increasing levels of MQ exhibited significantly higher body weight gains (BWGs) compared to the control group (p < 0.05). There was a clear linear increase in the breast muscle percentage with higher levels of quercetin supplementation (p < 0.05), while the breast color remained consistent across all groups (p > 0.05). Both cooking loss and drip loss exhibited a linear decrease as MQ levels in the diet increased (p < 0.05). The level of aspartate aminotransferase (AST) tended to decrease with higher MQ levels. Thyroxine (T4) and lymphocyte levels also showed a linear increase with increasing MQ dosage in the diet (p < 0.05). However, no significant effects were observed on nutrient digestibility, gas emissions, or fecal microbial components (Lactobacillus, E. coli, and Salmonella) with higher levels of MQ supplementation (p > 0.05). In conclusion, augmenting quercetin levels in the diet positively influenced the BWG, breast muscle development, and meat quality parameters such as cooking loss and drip loss, with beneficial effects on blood profiles.

Immunomodulatory Effects of Natural Feed Additives for Meat Chickens

Broiler chickens are increasingly kept in large numbers in intensive housing conditions that are stressful, potentially depleting the immune system. With the prohibition of the use of antibiotics in poultry feed spreading worldwide, it is necessary to consider the role of natural feed additives and antibiotic alternatives to stimulate the chickens' immune systems. We review the literature to describe phytogenic feed additives that have immunomodulatory benefits in broilers. We initially review the major active ingredients from plants, particularly flavonoids, resveratrol and humic acid, and then describe the major herbs, spices, and other plants and their byproducts that have immunomodulatory effects. The research reviewed demonstrates the effectiveness of many natural feed additives in improving the avian immune system and therefore broiler health. However, some, and perhaps all, additives have the potential to reduce immunocompetence if given in excessive amounts. Sometimes additives are more effective when given in combination. There is an urgent need to determine tolerance levels and optimum doses for additives deemed most suitable to replace antibiotics in the diet of broiler chickens. Effective replacement is most likely with readily available additives, such as olive oil byproducts, olive leaves and alfalfa. It is concluded that effective replacement of antibiotic function with plant-derived additives will be possible, but that further research is necessary to determine optimum doses.

Probiotics in Poultry Nutrition as a Natural Alternative for Antibiotics

Since the early 1950s, antibiotics have been used in poultry for improving feed efficiency and growth performance. Nevertheless, various side effects have appeared, such as antibiotic resistance, antibiotic residues in eggs and meat, and imbalance of beneficial intestinal bacteria. Consequently, it is essential to find other alternatives that include probiotics that improve poultry production. Probiotics are live microorganisms administered in adequate doses and improve host health. Probiotics are available to be used as feed additives, increasing the availability of the nutrients for enhanced growth by digesting the feed properly. Immunity and meat and egg quality can be improved by supplementation of probiotics in poultry feed. Furthermore, the major reason for using probiotics as feed additives is that they can compete with various infectious diseases causing pathogens in poultry's gastrointestinal tract. Hence, this chapter focuses on the types and mechanisms of action of probiotics and their benefits, by feed supplementation, for poultry health and production.

Herbs as thermoregulatory agents in poultry: An overview

The adverse effect of increased environmental temperature during summer season on avian industry has received great global concern. High temperature leads to severe economic loss in poultry production, because it is considered as valuable stress factor. Several practical methods were used to alleviate the adverse impact of increased temperature; among them were dietary modifications. So, several types of herbs are supplemented to reduce the deleterious influences of thermal stress altitudes in various animals, and even to prevent their adverse impacts. Therefore, sustainable supports for dietary modification based on herbs supplementations are largely needed, particularly when consider the additional advantages of herbs such as availability, actual efficiency, low cost, as well as their free from residual impact and antibiotic resistance. Numerous types of herbs were concluded to their efficient properties by poultry breeders to overcome a variety of the harmful effects of high ambient temperature. The present article deliberates the different practical applications of several members of the traditional herbal wealth to improve the general health state of poultry particularly as thermoregulatory and immunomodulatory agents, and for countering the heat stress-associated immunosuppressive effects. Additionally, the antioxidant activity of herbal growth promoters and their influence on improvement of production performances were a special aim of this review. The reported information will be helpful for improvement of general production and health status of birds reared under the heat stress via enhancement of immune response and stress tolerance, and popularizes usage of herbs amongst poultry producers.

Effects of star anise (Illicium verum Hook.f.) essential oil on nutrient and energy utilization of laying hens

An experiment using 96 Hy-Line brown laying hens at 29 weeks of age that were randomly allocated to four treatments with eight replicates was conducted to assess the effects of star anise (Illicium verum Hook.f.) oil (SAO) on nutrient and energy utilization. Dietary treatments were corn-soybean meal-based diets supplemented with 0, 200, 400, and 600 mg/kg SAO. The birds were fed the diets for 14 days. The conventional nutrients and amino acids of feed and excreta samples were measured for calculating apparent metabolic efficiency, and gross energy (GE) was analyzed for computation of apparent metabolic energy (AME) and true metabolic energy (TME). Endogenous losses were obtained from another 16 birds for calculating true metabolic efficiency. Birds supplemented with SAO had higher (p < 0.05) metabolic efficiency of crude protein (CP), organic matter (OM), Lys, Met, Arg, and Thr than those of control group. Quadratic effects on utilization of Lys, Met, and Thr were observed (p < 0.05). Inclusion of SAO to diet improved nutrient utilization, and the efficacy is best at 400 mg/kg.

Acute Oral Toxicity of Vetom 21.77 Based on Duddingtonia Flagrans in Broiler Chickens

A 14-d study was undertaken to test the acute toxicity of a new preparation Vetom 21.77 based on the predacious fungus Duddingtonia flagrans. A total of 40 healthy 5-day-old broiler chickens (Hubbard F15, 100 ± 5 g), that had previously gone through a required 5-days adaptation to the environment, were orally dosed with the drug for 5 consecutive days at different doses, after which their health status was assessed daily up to the end of the experiment. According to the results, no substantial changes in the physiological state of the chickens were detected during the experiment. Internal organs weighing revealed no statistically significant differences between the groups, though weight coefficient values of internal organs of treated chickens slightly exceeded those of the control group. Some haematological parameters were significantly higher in the treatment group, without going beyond reference ranges. All chickens used in the experiment survived the study. The preparation has not produced any toxic effect even at a higher dose (4000 µL/kg bw/day). It is concluded that Vetom 21.77 pertains to preparations of IV toxicity class.

Effects of Ginkgo biloba leaves (Ginkgo biloba) and Ginkgo biloba extract on nutrient and energy utilization of broilers

An experiment using 112 21-day-old male Arbor Acres broilers that were randomly allocated to 7 treatments with 8 replicates in a completely randomized design was conducted to assess the effects of Ginkgo biloba leaves (Ginkgo biloba, GL) and Ginkgo biloba extract (EGB) on utilization of nutrients of broiler chickens. The dietary treatments were corn-soybean meal based diets: 1) T1, control diet; 2) T2, T1 + 20 g/kg GL; 3) T3, T1 + 40 g/kg GL; 4) T4, T1 + 60 g/kg GL; 5) T5, T1 + 0.4 g/kg EGB; 6) T6, T1 + 0.8 g/kg EGB; and 7) T7, T1 + 1.2 g/kg EGB. Endogenous losses were obtained from another 16 broilers. Excreta samples were collected to analyze the dry matter (DM), organic matter (OM), ether extract (EE), crude protein (CP), gross energy (GE), and amino acids (AA), and GE was analyzed for computation of AME and TME. As compared with those of the control treatment, the apparent digestibility (AD) and true digestibility (TD) of EE, CP, Thr, Val, Ile, Leu, Phe, Lys, His, and Arg were quadratically (P < 0.05) increased; moreover, the AD and TD of Met was linearly (P < 0.05) increased as the concentration of the EGB in the diet increased. Increasing GL from 0 to 60 g/kg of diet linearly (P < 0.05) increased the AD and TD of EE, Thr, Val, Leu, His, and Met and tended (0.05 < P < 0.1) to increase the TME, TMEn, and Arg. Supplementation of EGB increased (P < 0.05) AD and TD of EE, Thr, Val, Ile, Leu, Phe, His, and Arg and tended (0.05 < P < 0.1) to increase Lys as compared with those in the GL-supplemented groups. Dietary supplementation of GL and EGB improved the utilization of nutrients of broiler chickens in a dose-dependent manner, and the optimum supplementation levels of GL or EGB in the diet of broilers was 60 or 0.8 g/kg of diet, respectively.

Growth performance, blood health, antioxidant status and immune response in red sea bream (Pagrus major) fed Aspergillus oryzae fermented rapeseed meal (RM-Koji)

This study evaluated the effects of dietary substitution of fishmeal by graded levels of a blend composed of Aspergillus oryzae fermented rapeseed meal [0% (RM0), 25% (RM25), 50% (RM50), 75% (RM75) and 100% (RM100)] on growth performance, haemato-immunological responses and antioxidative status of Pagrus major (average weight 5.5 ± 0.02 g). After 56 days, growth performances were significantly improved in fish fed RM25 diet compared to control (P < 0.05). Meanwhile, up to 50% replacement of fishmeal did not affect growth performance, feed conversion efficiency, protein efficiency ratio, protein apparent digestibility, protease activity, fish somatic indices and survival compared to control. While blood hematocrit and plasma protein were significantly enhanced in groups fed RM0 and RM25 diets, most of the hematological parameters did not change through the trial except glutamic pyruvate transaminase which was significantly increased in RM75 and RM100 groups and blood cholesterol which was gradually decreased with the increasing level of the blend. Interestingly, feeding fish with RM25 and RM50 diets significantly showed enhanced lysozyme, bactericidal and peroxidase activities and fish fed the same diets showed high resistance against oxidative stress (biological antioxidant potential and reactive oxygen metabolites). Additionally, catalase activity and tolerance against low salinity seawater were higher in fish fed RM25 diet. These findings suggested that, at a moderate level (25% and 50%), substitution of fishmeal by the fermented rapeseed meal promoted growth, nutrient utilization, and exerted immune responses and anti-oxidative effects in red sea bream.

Preventing subclinical necrotic enteritis through Lactobacillus johnsonii BS15 by ameliorating lipid metabolism and intestinal microflora in broiler chickens

Increasing studies have focused on the beneficial effects of Lactobacillus johnsonii in certain diseases. Here, we studied the prevention ability of a probiotic strain, L. johnsonii BS15 on subclinical necrotic enteritis (SNE), and its underlying mechanism. 180 male Cobb 500 chicks were randomly allotted into three groups and administrated with BS15 (1 × 10⁶ cfu/g) or Man Rogosa Sharpe liquid medium throughout a 28-day experimental period. With the exception of the normal group, SNE infection was treated for the remaining experimental period after the chicks were fed with normal diet 14 days. Results showed that BS15 notably suppressed the SNE-induced loss of average daily gain and liver functional abnormality. Additionally, BS15 facilitated lipid metabolism of SNE boilers when the contents of peroxisome proliferator activated receptor γ and adipose triglyceride lipase in adipose tissue and serum high-density lipoprotein cholesterol decreased. BS15 also attenuated the hepatic lipid accumulation of stricken chicks by suppressing the genes expression of acetyl-CoA carboxylase, fatty acid synthase and sterol regulatory element binding protein-1c as well as stimulating the genes expression of peroxisome proliferator activated receptor α and carnitine palmitoyltransferase-1. Moreover, BS15 enhanced the development of SNE gut by improving the intestinal development and digestion as well as adjusting the gut microflora. Therefore, BS15 may provide a promising natural preventative strategy against SNE, which may be contributed to the amelioration of lipid metabolism and intestinal microflora.