Dose-dependent response to phytobiotic supplementation in feed on growth, hematology, intestinal pH, and gut bacterial load in broiler chicken

Effects of Short- and Medium-Chain Fatty Acids on Production, Meat Quality, and Microbial Attributes-A Review

The non-therapeutic use of antimicrobials in poultry production contributes to the spread of drug-resistant pathogens in both birds and humans. Antibiotics are known to enhance feed efficiency and promote the growth and weight gain of poultry. New regulatory requirements and consumer preferences have led to a reduced use of antibiotics in poultry production and to the discovery of natural alternatives to antibiotic growth promoters. This interest is not only focused on the direct removal or inhibition of causative microorganisms but also on the prevention of diseases caused by enteric pathogens using a range of feed additives. A group of promising feed additives is composed of short- and medium-chain fatty acids (SCFAs and MCFAs) and their derivatives. MCFAs possess antibacterial, anticoccidial, and antiviral effects. In addition, it has been proven that these acids act in synergy if they are used together with organic acids, essential oils, or probiotics. These fatty acids also benefit intestinal health integrity and homeostasis in broilers. Other effects have been documented as well, such as an increase in intestinal angiogenesis and the gene expression of tight junctions. The aim of this review is to provide an overview of SCFAs and MCFAs as alternatives to antibiotic growth promoters and to summarize the current findings in the literature to show their possible benefits on production, meat quality, and gut health in poultry.

Effects of dietary supplementation with dandelion tannins or soybean isoflavones on growth performance, antioxidant function, intestinal morphology, and microbiota composition in Wenchang chickens

Many benefits have been found in supplementing tannins or soybean isoflavones to poultry, including increased body weight gain, antioxidant activity, and better intestinal morphology. However, few studies tested the influence of dandelion tannins or soybean isoflavones supplementation on Wenchang chickens. This study investigates the effects of dietary supplementation with dandelion tannins or soybean isoflavones on the growth performance, antioxidant function, and intestinal health of female Wenchang chickens. A total of 300 chickens were randomly divided into five groups, with six replicates per group and 10 broilers per replicate. The chickens in the control group (Con) were fed a basal diet; the four experimental groups were fed a basal diet with different supplements: 300 mg/kg of dandelion tannin (DT1), 500 mg/kg of dandelion tannin (DT2), 300 mg/kg of soybean isoflavone (SI1), or 500 mg/kg of soybean isoflavone (SI2). The experiment lasted 40 days. The results showed that the final body weight (BW) and average daily gain (ADG) were higher in the DT2 and SI1 groups than in the Con group (P < 0.05). In addition, dietary supplementation with dandelion tannin or soybean isoflavone increased the level of serum albumin (P <0.05); the concentrations of serum aspartate aminotransferase and glucose were significantly higher in the SI1 group (P < 0.05) than in the Con group and the concentration of triglycerides in the DT1 group (P < 0.05). The serum catalase (CAT) level was higher in the DT1 and SI1 groups than in the Con group (P < 0.05). The ileum pH value was lower in the DT2 or SI1 group than in the Con group (P < 0.05). The jejunum villus height and mucosal muscularis thickness were increased in the DT2 and SI1 groups (P < 0.05), whereas the jejunum crypt depth was decreased in the DT1 or DT2 group compared to the Con group (P < 0.05). In addition, the messenger RNA (mRNA) expression level of zonula occludens 1 (ZO-1) in the duodenum of the SI1 group and those of occludin, ZO-1, and claudin-1 in the ileum of the DT2 and SI1 groups were upregulated (P < 0.05) compared to the Con group. Moreover, the DT2 and SI1 groups exhibited reduced intestinal microbiota diversity relative to the Con group, as evidenced by decreased Simpson and Shannon indexes. Compared to the Con group, the relative abundance of Proteobacteria was lower and that of Barnesiella was higher in the DT2 group (P < 0.05). Overall, dietary supplementation with 500 mg/kg of dandelion tannin or 300 mg/kg of soybean isoflavone improved the growth performance, serum biochemical indexes, antioxidant function, and intestinal morphology and modulated the cecal microbiota composition of Wenchang chickens.

Willingness to Pay for Safe Chicken Meat in Bangladesh: A Contingent Valuation Approach

The poultry meat industry is primarily dominated by broilers, and conventional broiler meat is claimed to be malicious to human health and environment since it is produced using hazardous feeds and other dietary supplements. This study aimed to evaluate consumers’ willingness to pay (WTP) for safe broiler chicken meat following a contingent valuation model (CVM). Also, consumers’ consumption and different types of perceptions on safe broiler meat were assessed from the data collected among 300 consumers in Bangladesh. Consumers’ health and environmental perception of safe broiler meat are found to be high, indicating that they are more concerned about these attributes in the case of consuming broiler meat. The results reveal that conventional broiler meat losses its appeal to consumers after a certain income level and is mainly consumed by lower- and middle-income groups. This study divulges a unanimous demand for safe broiler meat among the consumers who intend to consume about 36% higher than their present consumption level if the availability was ensured in their local market. The average WTP premium for safe broiler meat is estimated to be about BDT 39.87 per kg. The consumers’ WTP is positively influenced by their education, income level, the current consumption of broiler chicken meat, health perception, and taste and nutrition perception. This study recommends meat producers, entrepreneurs, and farmers adjust their production and marketing plans by incorporating suitable quality control procedures to meet the unfilled consumer demand for safer broiler meat. Besides, slow-growing safer broiler chicken needs to be introduced to improve meat’s taste and nutritional aspects.

Role of Different Growth Enhancers as Alternative to In-feed Antibiotics in Poultry Industry

The poultry industry has grown so fast alongside the irrational use of antibiotics to maximize profit and make the production cost-effective during the last few decades. The rising and indiscriminate use of antibiotics might result in the deposition of residues in poultry food products and in the development of resistance to these drugs by microorganisms. Therefore, many diseases are becoming difficult to treat both in humans and animals. In addition, the use of low-dose antibiotics as growth enhancer results in antibiotic residues in food products, which have detrimental effects on human health. On the other hand, many studies have shown that antibiotics administered to poultry and livestock are poorly absorbed through the gut and usually excreted without metabolism. These excreted antibiotics eventually accumulate in the environment and enter the human food chain, resulting in the bioaccumulation of drug residues in the human body. In this regard, to find out alternatives is of paramount importance for the production of safe meat and egg. Therefore, in recent years, much research attention was disarticulated toward the exploration for alternatives to antibiotic as in-feed growth enhancers after its ban by the EU. As a result, probiotics, prebiotics, phytobiotics, spirulina, symbiotic, and their combination are being used more frequently in poultry production. Feed additives therefore gained popularity in poultry production by having many advantages but without any residues in poultry products. In addition, numerous studies demonstrating that such biological supplements compete with antimicrobial resistance have been conducted. Therefore, the purpose of this review article was to highlight the advantages of using biological products instead of antibiotics as poultry in-feed growth enhancers to enhance the production performance, reduce intestinal pathogenic bacteria, and maintain gut health, potentiating the immune response, safety, and wholesomeness of meat and eggs as evidence of consumer protection, as well as to improve the safety of poultry products for human consumption.

Improvement of Growth performance, Biochemical Blood Profiles, and Meat Peroxidation by the Inclusion of Mustard Seed Extract in Broilers' Drinking Water

Growth promoters are used in the broiler industry of Iraq, and herbal plants are believed to be one of the safest growth-promoting agents in modern poultry production. This study aimed to investigate the effect of aqueous mustard (Brassica juncea) seed (MS) extract on broiler production. A total of 160 unsexed day-old Ross 308 broiler chicks were selected and exposed to different doses of MS included in drinking water for six weeks. Afterward, MS was added to the treatment groups of T1 (control), T2, T3, and T4 in the dosage of 0mL, 3mL, 5 mL, and 7 mL per liter of drinking water, respectively. Results indicated that the birds that were given extract (T2, T3, T4) for the three weeks were fed significantly more diet, compared to the control treatment group (189.4 g vs. 159.6g) (P<0.05). Accordingly, the Body Weight (BW) of these birds recorded on days 28 (1232, 1252, 1300g) and 35 (1840, 1900, 1960g) were significantly higher, compared to the birds in the control treatment on days 28 (1147g) and 35 (1657g), respectively. On days 28 and 35, the birds in T2, T3, T4 treatment groups had significantly higher Body Weight Gain (BWG) (P<0.05), compared to the control group (G1). Improved Feed Conversion Ratio (FCR) was observed in the 5^th week for the birds that were administrated MS extract (5 and 7mL /liter), compared to the control group (P<0.05). The total serum level of protein, phosphorus, and calcium was increased in birds in the treatment group T4 (7.5 g/dL). Moreover, lower cholesterol values and higher values of alkaline phosphatase were obtained in birds in the treatment groups T2, T 3, and T4 (P<0.05). On day 35, higher meat peroxidation was observed in the fresh samples (after 24 h of slaughtering) of birds receiving different levels of MS extract, compared to the birds in the control group. The obtained results revealed that 5-7 mL of MS extract can be considered a functional growth- promoter for commercial broilers, although further studies are needed to confirm MS as a growth promoter.

Potential role of important nutraceuticals in poultry performance and health - A comprehensive review

Antibiotics use in poultry as a growth promoter leads to the propagation of antibiotic-resistant microorganisms and incorporation of drug residues in foods; therefore, it has been restricted in different countries. There is a global trend to limit the use of antibiotics in the animal products. Prevention of the antibiotics use in the poultry diets led to the reduction in the growth performance. Consequently, there is a high demand for natural substances that lead to the same growth enhancement and beneficially affect poultry health. These constituents play essential roles in regulating the normal physiological functions of animals including the protection from infectious ailments. Nutraceuticals administration resulted beneficial in both infectious and noninfectious diseases. Being the natural components of diet, they are compatible with it and do not pose risks associated with antibiotics or other drugs. Nutraceuticals are categorized as commercial additives obtained from natural products as an alternative feed supplement for the improvement of animal welfare. This group includes enzymes, synbiotics, phytobiotics, organic acids and polyunsaturated fatty acids. In the present review, the summary of various bioactive ingredients that act as nutraceuticals and their mode of action in growth promotion and elevation of the immune system has been presented.

Comparative Efficacy of Selected Phytobiotics with Halquinol and Tetracycline on Gut Morphology, Ileal Digestibility, Cecal Microbiota Composition and Growth Performance in Broiler Chickens

Simple Summary

Antimicrobial growth promoters (AGPs) are banned in Europe but still used in many countries including Asia. However, their indiscriminate use resulted in antibiotic-resistant bacterial strains that possibly transfer the resistant genes to the microorganisms pertinent to human health. Hence, it is essential to find alternatives that can improve the production performance in broiler chickens. In this scenario, phytobiotics or phytogenic feed additives (PFAs) are widely investigated to evaluate their influence on improving gut health, increasing digestibility, and thereby the growth performance. The present study is a continuity of our experiments on dietary inclusion of Piper betle and Persicaria odorata leaf meal and the first of its kind to evaluate the comparative efficacy of phytobiotics (Piper betle and Persicaria odorata leaf meal), with halquinol and tetracycline in broiler chickens. The current experiment findings indicated that, in comparison with the control group, either of the dietary treatments positively modulated the gut morphology, improved ileal digestibility, maintained the intestinal population of Lactobacillus and reduced the pathogenic bacteria such as Staphylococcus aureus, Salmonella, Escherichia coli, and Clostridium spp., thus improved the growth performance in broiler chickens.

Abstract

The current experiment was designed to estimate the comparative efficacy of selected phytobiotics Persicaria odorata leaf meal (POLM) and Piper betle leaf meal (PBLM) with halquinol, and tetracycline in broiler chickens. The 150-day-old broiler chickens were randomly assigned to five dietary groups. The dietary supplementation groups were the basal diet (BD), which served as the negative control (NC), and BD + 0.2 g/kg tetracycline, which served as the positive control (PC); BD + 0.03 g/kg halquinol (HAL), BD + 8 g/kg POLM (Po8), and BD + 4 g/kg PBLM (Pb4) were the treatment groups. Growth performance, gut morphology, ileal digestibility, and cecal microbiota composition were measured. On day 21, the body weight gain (BWG) was enhanced (p < 0.05) in the broiler chickens fed on phytobiotics (Po8 and Pb4) relative to the NC group, however, on day 42 and in terms of overall growth performance, BWG was enhanced (p < 0.05 in diets (Po8, Pb4, HAL and PC) in comparison with the NC group. Conversely, feed conversion ratio (FCR) was recorded reduced (p < 0.05) in Pb4, Po8, HAL, and PC group in comparison with the NC group. Supplementation of phytobiotics (Po8 and Pb4), HAL and PC, positively improved the gut morphology compared to the NC group. Furthermore, the maximum (p < 0.05) villus height (VH) in duodenum and jejunum was observed in broilers fed on diet Pb4. Supplementation of phytobiotics, HAL and PC, improved (p < 0.05) the digestibility of dry matter (DM) (except for HAL), organic matter (OM), crude protein (CP), ether extract (EE), and ash compared to the NC group. Dietary supplementation of phytobiotics (Po8 and Pb4), HAL and PC, significantly reduced the E. coli, Salmonella, and Staphylococcus aureus (except for HAL) counts compared to the NC group. However, supplementation of Pb4 resulted in significantly decreased total anaerobic bacteria and Clostridium spp. counts compared to the NC group. In addition, supplementation of phytobiotics significantly increased the Lactobacillus count compared to HAL, PC, and NC groups. In conclusion, dietary supplementation of phytobiotics improved the gut morphology, positively modulated and maintained the dynamics of cecal microbiota with enhanced nutrient digestibility, thus, increased the growth performance. Based on current results, phytobiotics could be used as an alternative to AGPs for sustainable broiler chicken production.

Effect of discriminate and indiscriminate use of oxytetracycline on residual status in broiler soft tissues

Aim:

This study aimed to evaluate the effects of discriminate and indiscriminate use of oxytetracycline on hematological parameters, residual status in soft tissue of broiler and of thermal effect on oxytetracycline residual status.

Materials and Methods:

Eighteen, day-old male broiler chickens were purchased and were divided into three different groups (control group, discriminate group, and indiscriminate group). The control group received no antibiotics. The discriminate group received oxytetracycline 1 g/L drinking water for 5 consecutive days, and 10 days’ withdrawal period was maintained before sacrifice. The indiscriminate group received oxytetracycline 1 g/L drinking water till the sacrificed day. Blood samples were collected before sacrificing for hematological analysis. After sacrificing liver, kidney, spleen, and muscle samples were collected for analysis of oxytetracycline residues in raw soft tissues. Since meat is used to cook by traditional method in Bangladesh before consumption that is why positive meat samples were cooked by traditional cooking method to evaluate the thermal effect on oxytetracycline residual status as well. Thin-layer chromatography (TLC) was done for screening of oxytetracycline residues in soft tissues.

Results:

Mean differences of total erythrocyte count (million/mm³), hemoglobin estimation (gm%), and packed cell volume (%) estimation were not statistically significant among the groups. TLC analysis of raw samples showed 100% positive results of all samples collected from the indiscriminate group. In contrast, samples collected from the discriminate group were negative for oxytetracycline residues. In the control group, all samples were negative for oxytetracycline residue. There was a significant (p<0.05) relationship of oxytetracycline residues among three different groups for liver, kidney, spleen, and muscle samples. Positive liver and muscle samples from the indiscriminate group were subjected to thermal treatment by traditional cooking method of Bangladesh. Oxytetracycline residues had found in cooked meat, liver, and juice part, suggesting that antibiotic residues disseminated to juice part from flesh part after cooking.

Conclusion:

Evidence suggests that proper maintenance of withdrawal period would minimize oxytetracycline residues in broiler soft tissues, whereas antibiotics retained in soft tissues of broiler in case of indiscriminate use. Traditional cooking does not change oxytetracycline residual status in edible tissues. Therefore, awareness regarding the proper maintenance of withdrawal period after antibiotic treatment of broiler is one of the best strategies which may positively reduce the risk of antimicrobial drugs residue in meat.

Beneficial effects of probiotic and phytobiotic as growth promoter alternative to antibiotic for safe broiler production

Objectives:

Drug residues in poultry products could lead to the development of antibiotic-resistant bacteria as in any living animal and human alike. Extensive use of antibiotics in animals to promote growth rate, increase feed efficiency, and for prevention of intestinal infections has led to the development of resistant bacteria in the gastrointestinal tract. The present study was conducted to evaluate the effects of biological supplementation of probiotic, phytobiotic, and their combination over antibiotic on growth performance, microbial load, and hematological parameters in Broiler.

Materials and methods:

Sixty-five broiler chicken were divided into five groups (12 birds in each group), namely, group A (basal diet), group B (antibiotic, Renamycin 100®), group C (phytobiotic, Galibiotic®), group D (probiotic, Bio-Top®), and group E (combination, Galibiotic®+Galibiotic®) and five were sacrificed for baseline data on day 0.

Results:

Average final live weight gain was highest in group D (probiotic) than other groups. The feed conversion ratio was highest in group A and lowest in the probiotic group (group C). Blood samples were collected on 14th and 28th day for hematological studies. The mean hematology values regarding the total erythrocyte count, hemoglobin concentration, packed cell volume, and erythrocyte sedimentation rate differed significantly (p < 0.05) among groups. The pH of all the treatment groups was significantly decreased compared to the control group (p < 0.05) where group C was significantly (p < 0.05) lower than all other groups. Highest total viable cell count was observed in control (group A) and total coliform count in phytobiotic (group C) was significantly lower than in other treatment groups (p < 0.05).

Conclusion:

It may conclude that biological supplements have a significant positive impact on growth performance, hematological parameters, and gut microbial load in broiler chicken of which the probiotic showing the best effects. Supplementation of probiotic in feed could be one of the best candidates as an alternative to antibiotics as growth promoter for safe broiler production.