We investigated the effects of Clostridium butyricum and Enterococcus faecalis (probiotics) in a piglet model. Weaned piglets (180) were randomly divided into three treatment groups and fed basal diet and basal diet supplemented with 6 × 109 CFU C. butyricum per kg and 2 × 1010 CFU E. faecalis per kg, respectively. The probiotics improved the final body weight, average daily gain, and feed conversion rate, while they reduced the diarrhea rate. The serum aspartate aminotransferase and alanine aminotransferase activities in probiotic-supplemented piglets were decreased on days 14 and 28. Piglets supplemented with probiotics presented an increased serum immunoglobulin (Ig)M level on day 14 and IgA, IgG, and IgM levels on day 28 compared with control piglets, respectively. Moreover, the probiotics increased the jejunal villus length and jejunal villus height to crypt depth ratio, while they decreased the jejunal crypt depth compared with those of the control. Similarly, an increase in inflammation-related pathway factor expression was observed after probiotic administration. Piglets supplemented with probiotics had a higher concentration of volatile fatty acids in the colonic contents than that in the control. High-throughput sequencing indicated that the probiotics modulated the colon bacterial diversity. Species richness and the alpha diversity index of bacterial samples in probiotic-supplemented piglets were higher than those in the control. Piglets supplemented with C. butyricum presented a considerably high relative abundance of C. butyricum compared with that in the control. Overall, C. butyricum and E. faecalis can promote growth performance, protect the intestinal villi morphology, improve immunity, and optimize the intestinal flora in weaned piglets.

Effects of Clostridium butyricum and Enterococcus faecalis on growth performance, immune function, intestinal morphology, volatile fatty acids, and intestinal flora in a piglet model.

Over the years the growth and health of food-producing animals have been enhanced by the use of antibiotics. These have helped reduce on-farm mortalities, lower incidences of diseases and more importantly improve productivity. Generally, the utilization of antibiotics in feed has been reevaluated since bacterial pathogens have established and shared a variety of antibiotic resistance mechanisms that can easily be spread within microbial communities. Multiple countries have introduced bans or severe restrictions on the non-therapeutic use of antibiotics. This has therefore warranted the urgent need for alternatives. Africa is facing its own challenges as it has been reported to be one of the continents with the highest number of foodborne diseases with approximately 91 million related diseases and 137,000 death per annum. Stakeholder and policy direction has been put in place to curb this escalation; however, the problem persists. The use of alternatives has been recommended and some successfully used in other countries as well as Africa, including pro- and prebiotics and phytochemicals. This then leads to the core aim of this review which is to (1) determine the extent to which antimicrobial-resistant pathogens have affected Africa, (2) assess the current measures put in place by Africa to reduces antimicrobial resistance and finally (3) explore the alternative use of antibiotics in poultry production. Improved sanitary conditions and farm biosecurity are important alternatives that could be adopted by farmers instead of depending on antibiotic drugs for disease control and prevention.

The Current Status of the Alternative Use to Antibiotics in Poultry Production: An African Perspective.

Antibiotic-free broiler meat production is becoming increasingly popular worldwide due to consumer perception that it is superior to conventional broiler meat. Globally, broiler farming impacts the income generation of low-income households, helping to alleviate poverty and secure food in the countryside and in semi-municipal societies. For decades, antibiotics have been utilized in the poultry industry to prevent and treat diseases and promote growth. This practice contributes to the development of drug-resistant bacteria in livestock, including poultry, and humans through the food chain, posing a global public health threat. Additionally, consumer demand for antibiotic-free broiler meat is increasing. However, there are many challenges that need to be overcome by adopting suitable strategies to produce antibiotic-free broiler meat with regards to food safety and chicken welfare issues. Herein, we focus on the importance and current scenario of antibiotic use, prospects, and challenges in the production of sustainable antibiotic-free broiler meat, emphasizing broiler farming in the context of Bangladesh. Moreover, we also discuss the need for and challenges of antibiotic alternatives and provide a future outlook for antibiotic-free broiler meat production.

https://www.mdpi.com/2079-7737/9/11/411/pdf

Sustainable Antibiotic-Free Broiler Meat Production: Current Trends, Challenges, and Possibilities in a Developing Country Perspective.

Heat stress, one of the critical obstacles to poultry sector in subtropical and tropical countries, reduces performance, immune response, and animal welfare. This study examined the effect of dietary inclusion of probiotic (PRO), citric acid (CIT), garlic powder (GAR) or their combinations on growth, blood constituents, ileal microflora and morphology and humoral immunity of broiler chickens subjected to cyclic heat stress. Four hundred ninety one-day-old Ross-308 broiler chicks were randomly allocated to 7 groups with 7 replicates of 10 birds each as follows: control (C) group received the basal diet without supplements, PRO, CIT and GAR groups supplemented with 0.5 g kg−1 multi-strain probiotic mixture (MPM), citric acid and garlic powder, respectively. PRO-CIT and PRO-GAR groups treated with 0.5 g kg−1 MPM, and 0.5 g kg−1 citric acid and garlic powder, while CIT-GAR group fed diet with 0.5 g kg−1 of citric acid and garlic powder. Results revealed that dietary supplements and their combinations improved (P < 0.001) growth performance and decreased abdominal fat of heat-stressed birds. Dietary supplements decreased (P < 0.01) serum concentrations of cholesterol, triglycerides and LDL, while HDL was elevated (P < 0.05). Feed additives reduced (P < 0.01) ileal enumeration of Escherichia coli and total coliform while Lactobacillus count was increased (P < 0.05) only in MPM-enriched groups. Supplementation of these natural products improved (P < 0.01) ileal architecture while humoral immune response was not significantly influenced except antibody titre against Newcastle disease virus which was increased (P < 0.05) in MPM-supplemented groups. Conclusively, addition of the dietary supplements and their combinations, particularly, probiotic and citric acid combination can improve productive performance, and intestinal flora and histomorphometry of broilers exposed to cyclic heat stress.

Impact of multi-strain probiotic, citric acid, garlic powder or their combinations on performance, ileal histomorphometry, microbial enumeration and humoral immunity of broiler chickens.

The elevation of ambient temperature beyond the thermoneutral zone leads to heat stress, which is a growing health and welfare issue for homeothermic animals aiming to maintain relatively constant reproducibility and survivability. Particularly, global warming over the past decades has resulted in more hot days with more intense, frequent, and long-lasting heat waves, resulting in a global surge in animals suffering from heat stress. Heat stress causes pathophysiological changes in animals, increasing stress sensitivity and immunosuppression, consequently leading to increased intestinal permeability (leaky gut) and related neuroinflammation. Probiotics, as well as prebiotics and synbiotics, have been used to prevent or reduce stress-induced negative effects on physiological and behavioral homeostasis in humans and various animals. The current data indicate dietary supplementation with a Bacillus subtilis-based probiotic has similar functions in poultry. This review highlights the recent findings on the effects of the probiotic Bacillus subtilis on skeletal health of broiler chickens exposed to heat stress. It provides insights to aid in the development of practical strategies for improving health and performance in poultry.

Bacillus subtilis-Based Probiotic Improves Skeletal Health and Immunity in Broiler Chickens Exposed to Heat Stress.

This study compared five commercially available probiotics vis-a-vis antibiotic growth promotant (AGP) supplementation and absence of feed additive based on efficiency, intestinal morphometry, and energy digestibility in improving broiler chicken production. A total of 630 straight run (Cobb) day-old broiler chicks were distributed to seven treatments following a completely randomized design, with ten replicates per treatment and nine birds per replicate per cage. Dietary treatments consisted of basal diet in combination with the following: without probiotics and AGP supplementation (treatment 1); 75 ppm each of chlorotetracycline (CTC) and Zn bacitracin (treatment 2); probiotic A, Bacillus subtilis (treatment 3); probiotic B, Bacillus subtilis (treatment 4); probiotic C, Enterococcus faecium (treatment 5); and probiotic D, Bacillus subtilis (treatment 6); probiotic E, Enterococcus faecium, Bifidobacterium spp., Pediococcus spp., and Lactobacillus spp. (treatment 7). At day 42, energy digestibility was determined by fasting three randomly selected birds from each treatment for 12 h and then subjecting them to their corresponding dietary treatments. Excreta were collected and pooled after 24 h of feeding. Pooled excreta were weighed, oven-dried, and subjected to energy analyses after 3-day collection. Apparent total tract metabolizable energy was then computed. At day 47, three birds were randomly selected per treatment for intestinal morphometry (villi height and crypt depth) of the duodenum, jejunum, and ileum. Dietary supplementation using probiotics showed no significant effect on overall body weight, weight gain, feed consumption, feed efficiency, dressing percentage, mortality, harvest recovery, carcass quality parameters (e.g., meat to bone ratio and abdominal fat content), intestinal morphometry, and energy digestibility. Birds under treatment 7 (basal feed + probiotic E) generated the highest income over feed and chick cost.

Precious Jewel D Dela Cruz

Papers

Dietary effects of commercial probiotics on growth performance, digestibility, and intestinal morphometry of broiler chickens