Ceca Of Birds Research Articles

Tetracycline resistance gene transfer from Escherichia coli donors to Salmonella Heidelberg in chickens is impacted by the genetic context of donors

Chicken ceca are a rich source of bacteria, including zoonotic pathogens such as Salmonella enterica. The microbiota includes strains/species carrying antimicrobial resistance genes and horizontal transfer of resistance determinants between species may increase the risk to public health and farming systems. Possible sources of these antimicrobial resistance donors – the eggshell carrying bacteria from the hen vertically transmitted to the offspring, or the barn environment where chicks are hatched and raised – has been little explored. In this study, we used Salmonella enterica serovar Heidelberg to evaluate if layer chicks raised in different environments (using combinations of sterilized or non-sterile eggs placed in sterilized isolation chambers or non-sterile rooms) acquired transferable tetracycline resistance genes from surrounding bacteria, especially Escherichia coli. Two-day old chicks were challenged with an antibiotic-susceptible S. Heidelberg strain SH2813nalR and Salmonella recovered from the cecum of birds at different timepoints to test the in vivo acquisition of tetracycline resistance. Tetracycline-resistant E. coli isolates recovered from birds from the in vivo experiment were used to test the in vitro transfer of tetracycline resistance genes from E. coli to Salmonella. Even though Salmonella SH2813nalR colonized the 2-day old chicks after oral challenge, tetracycline-resistant Salmonella transconjugants were not recovered, as previously observed. In vitro experiments provided similar results. We discuss several hypotheses that might explain the absence of transconjugants in vitro and in vivo, despite the presence of diverse plasmids in the recovered E. coli. The factors that can inhibit/promote antimicrobial resistance transfers to Salmonella for different plasmid types need further exploration.

The effect of supplemental arginine on the gut microbial homeostasis of broilers during sub-clinical necrotic enteritis challenge.

Necrotic enteritis (NE) is an enteric disease of poultry that alters the structure of the gut microbial community causing dysbiosis. This 28day experiment investigated the effects of 125% and 135% arginine diets on the gut microbial diversity and composition of broilers during a subclinical NE challenge. One hundred and twenty one-day-old chicks were randomly allocated to 4 treatments with six replicates each- Uninfected + Basal, NE + Basal, NE + Arg 125%, and NE + Arg 135% diet groups. NE was induced by inoculating 1 × 104E. maxima sporulated oocysts on day 14 and 1 × 108CFUC. perfringens on days 19, 20, and 21 of age. The NE challenge significantly decreased the number of observed amplicon sequence variants (p = 0.03), the abundance of the phylum Firmicutes (p < 0.01), and the species Mediterraneibacter cottocaccae (p = 0.01) in the ceca of birds on day 21. The NE challenge significantly increased the Bray-Curtis index (p < 0.01), and the abundance of the phylum Bacteroidota (p < 0.01), family Odoribacteraceae (p < 0.01), genus Odoribacter (p < 0.01), and species O. splanchnicus (p = 0.01) on day 21. During NE, the 125% arginine diet restored the abundance of the phylum Bacteroidota (p = 0.03), family Odoribacteraceae (p = 0.03) and Oscillospiraceae (p = 0.03), genus Odoribacter (p = 0.03), and species O. splanchnicus (p = 0.03) and M. cottocaccae (p < 0.01) on day 21. The 135% arginine diet effectively restored the loss in alpha diversity (p = 0.01) caused by NE, the abundance of the phylum Firmicutes (p = 0.01) and Bacteroidota (p < 0.01), family Oscillospiraceae (p = 0.03) and Odoribacteraceae (p < 0.01), genus Odoribacter (p < 0.01), and species O. splanchnicus (p < 0.01) and M. cottocaccae (p < 0.01) on day 21. On day 28, the treatments had a significant effect on the cecal propionate (p = 0.01), butyrate (p = 0.04), and total SCFA (p = 0.04) concentrations. In conclusion, the 125% and 135% arginine diets restored gut microbial composition during a subclinical NE challenge, but not the cecal SCFA profile. Hence, arginine in combination with other feed additives could be used in restoring gut microbial homeostasis during NE in poultry.

Investigation of Potential Gut Health Biomarkers in Broiler Chicks Challenged by Campylobacter jejuni and Submitted to a Continuous Water Disinfection Program.

The exploration of novel biomarkers to assess poultry health is of paramount importance, not only to enhance our understanding of the pathogenicity of zoonotic agents but also to evaluate the efficacy of novel treatments as alternatives to antibiotics. The present study aimed to investigate potential gut health biomarkers in broiler chicks challenged by Campylobacter jejuni and subjected to a continuous water disinfection program. A total of 144 one-day-old hatched broiler chicks were randomly allocated to four treatment groups with four replicates each, according to the following experimental design: Group A received untreated drinking water; Group B received drinking water treated with 0.01-0.05% v/v Cid 2000™ (hydrogen peroxide, acetic acid and paracetic acid); Group C was challenged by C. jejuni and received untreated drinking water; and Group D was challenged by C. jejuni and received drinking water treated with 0.01-0.05% v/v Cid 2000™. The use of Cid 2000™ started on day 1 and was applied in intervals until the end of the experiment at 36 days, while the C. jejuni challenge was applied on day 18. Potential biomarkers were investigated in serum, feces, intestinal tissue, intestinal content, and liver samples of broilers. Statistical analysis revealed significant increases (p < 0.001) in serum cortisol levels in C. jejuni-challenged broilers. Serum fluorescein isothiocyanate dextran (FITC-d) increased significantly (p = 0.004) in broilers challenged by C. jejuni and treated with drinking water disinfectant, while fecal ovotransferrin concentration also increased significantly (p < 0.001) in broilers that received the drinking water disinfectant alone. The gene expression levels of occludin (p = 0.003) and mucin-2 (p < 0.001) were significantly upregulated in broilers challenged by C. jejuni, while mucin-2 significantly increased in birds that were challenged and received the drinking water disinfectant (p < 0.001). TLR-4 expression levels were significantly (p = 0.013) decreased in both groups that received the drinking water disinfectant, compared to the negative control group. Finally, the C. jejuni challenge significantly increased (p = 0.032) the crypt depth and decreased (p = 0.021) the villus height-to-crypt-depth ratio in the ileum of birds, while the tested disinfectant product increased (p = 0.033) the villus height in the jejunum of birds. Furthermore, the counts of C. jejuni in the ceca of birds (p = 0.01), as well as its translocation rate to the liver of broilers (p = 0.001), were significantly reduced by the addition of the water disinfectant. This research contributes to novel insights into the intricate interplay of water disinfection and/or C. jejuni challenge with potential intestinal biomarkers. In addition, it emphasizes the need for continued research to unveil the underlying mechanisms, expands our understanding of broiler responses to these challenges and identifies breakpoints for further investigations.

The effects of fermented feedstuff derived from Citri Sarcodactylis Fructus by-products on growth performance, intestinal digestive enzyme activity, nutrient utilization, meat quality, gut microbiota, and metabolites of broiler chicken.

This research aimed to assess the impact of fermented Citri Sarcodactylis Fructus by-products (FCSF) on the growth performance, gut digestive enzyme activity, nutrient utilization efficiency, gut microbiota, and their metabolites in broiler chickens. A total of 1,080 male broiler chickens were allocated into four groups (T1-T4) consisting of 6 replicates per group, each containing 45 chickens. The basal diet was provided to group T1, while groups T2, T3, and T4 were supplemented with 1%, 3%, and 5% FCSF in the basal diet, respectively. The experimental period was 42 days. The findings revealed that supplementing FCSF improved the FW and ADG of broiler chickens, and led to a reduction in the F/G, ADFI, and mortality rate of broiler chickens (p < 0.05). Furthermore, supplementation with 3% and 5% FCSF improved the thigh yield, semi-eviscerated carcass yield, slaughter yield, and lipase activity in the duodenum and ileum of birds (p < 0.05). Additionally, supplementing 3% FCSF enhanced the activity of protease in the duodenum of broilers (p < 0.05). Moreover, supplementing 3% FCSF enhanced the utilization of total phosphorus, dry matter, crude protein, and crude ash in the feed by broilers (p < 0.05). Compared with the control group, supplementation of 3% and 5% FCSF reduced the serine content in broiler chicken breast meat (p < 0.05). Supplementing 1% FCSF significantly increased the C14:0, C14:1, and C20:1 content in the breast meat compared to the other experimental groups (p < 0.05). The levels of C20:4n6 and C23:0 in the breast meat of birds of FCSF supplemented groups were lower than in T1 (p < 0.05). Furthermore, the content of ∑ω-3PUFA decreased after supplementing with 3% and 5% FCSF (p < 0.05). 16SrDNA showed that supplementing 3% FCSF reduced the ACE, Chao1, and Shannon indices in the cecum of birds (p < 0.05). Supplementing 3% FCSF also decreased the abundance of the phylum Desulfobacterota and improved genera Coprobacter and Prevotella in the cecum of broiler chickens (p < 0.05). Metabolomic analysis of the gut microbiota revealed that supplementing 3% FCSF upregulated 6 metabolites and downregulated 16 metabolites (p < 0.05). Moreover, supplementing 3% FCSF downregulated 12 metabolic pathways and upregulated 3 metabolic pathways (p < 0.05). In summary our findings indicate that supplementing FCSF can improve the growth performance of broiler chickens by enhancing intestinal digestive enzyme activity, nutrient utilization, improving gut microbial diversity, and influencing the metabolism of gut microbiota.

Investigation of the Effect of Three Commercial Water Acidifiers on the Performance, Gut Health, and Campylobacter jejuni Colonization in Experimentally Challenged Broiler Chicks.

This study investigated the effect of three commercial water acidifiers on the performance, gut health, and C. jejuni colonization in experimentally challenged broiler chicks. A total of 192 one-day-old broiler chicks (Ross 308®) were randomly allocated into 6 treatment groups with 4 replicates according to the following experimental design: group A, birds were not challenged and received tap water; group B, birds were challenged and received tap water; groups C, D, E, and F, birds were challenged and received tap water treated with 0.1% v/v SPECTRON®, with 0.1-0.2% v/v ProPhorce™ SA Exclusive, with 0.1-0.2% v/v Premium acid, and with 0.1-0.2% v/v Salgard® Liquid, respectively. The continuous water acidification evoked undesirable effects on broilers' performance and to an increased number of birds with ulcers and erosions in the oral cavity and the upper esophageal area. ProPhorce™ SA Exclusive and Premium acid significantly reduced the C. jejuni counts in the crop, whereas Salgard® Liquid significantly reduced the C. jejuni counts in the ceca of birds. At slaughter age, only Premium acid significantly reduced C. jejuni counts in the ceca of birds. All the tested products ameliorated the changes induced by C. jejuni infection in the pH in the ceca of birds. It can be concluded that besides the effectiveness of the tested products in controlling C. jejuni in broilers, their continuous application evoked undesirable effects on broilers' performance, leading to the need to modify the dosage scheme in future investigations.

Effects of Different Papua New Guinea Sweetpotato Varieties on Performance and Level of Enteric Pathogens in Chickens.

Simple SummaryThe smallholder poultry industry in Papua New Guinea (PNG) has grown rapidly in the last decade. The cost of growing meat birds is high, as feed alone makes up to 80% of the total cost of production in PNG. Sweetpotato is currently used in a poultry feed as a cheaper alternative option compared to the more expensive commercially manufactured stockfeed in PNG. The PNG smallholder poultry production system involves many families who rear multiple batches of meat birds every year. These birds are sold mostly at the farm gate, at local provincial markets, or roadside markets. Consumption of contaminated chicken meat has been identified as one of the important food vehicles for food borne illness. This PNG-based study was conducted to understand whether the inclusion of local sweetpotato in poultry feed can influence the shedding of pathogens such as Clostridium perfringens, Salmonella and Campylobacter without causing negative effects on poultry performance. The results of this study releveled that Campylobacter and Salmonella levels in the broilers fed with the local sweetpotato diets can be influenced with inclusion of enzymes in the feed. In the last decade, research has targeted the evaluation of local feed ingredients for use in monogastric diets to alleviate the high cost of production of livestock at smallholder levels in Papua New Guinea (PNG). The PNG smallholder poultry production system involves many families who rear multiple batches of meat birds every year. This study was conducted to evaluate the levels of enteric pathogens in the caeca of broilers fed with sweetpotato diets with varying levels of non-starch polysaccharides (NSP). Selection of a sweetpotato variety for use in broiler diets should be based on the total NSP content. In particular, varieties with low soluble NSPs are economical to use as Apparent Metabolizable Energy (AME) values are within the desired range for poultry and there is minimal need to include enzymes to improve NSP digestibility. The use of varieties with a low total NSP is also advantageous as the numbers of Clostridium perfringens was lower in broilers fed with these sweetpotato varieties. The level of Campylobacter and Salmonella levels were high in the ceca of birds fed with the sweetpotato varieties with high total NSP. These levels can be reduced with the inclusion of enzymes. This information will assist in the efficient use of local varieties of sweetpotato in PNG by small holder poultry farmers for sustainable poultry production and the commercial industry.

Effects of Dietary Supplementation of Recombinant Plectasin on Growth Performance, Intestinal Health and Innate Immunity Response in Broilers.

The present study was conducted to evaluate the effects of dietary supplementation of recombinant plectasin (Ple) on the growth performance, intestinal health, and serum immune parameters in broilers. A total of 288 1-day-old male broilers (Arbor Acres) were randomly allotted to four dietary treatments including the basal diet (NC) and basal diet supplemented with 10mg enramycin/kg (PC), 100mg Ple/kg (LPle), and 200mg Ple/kg (HPle) diets. The results indicated Ple increased (P < 0.01) average daily gain and decreased (P ≤ 0.02) feed to gain ratio of broilers. In addition, the supplementation of Ple in the diets increased (P ≤ 0.01) duodenal lipase (day 21) and trypsin (day 42) activities compared with the NC group. Similar as the supplementation of enramycin, Ple also increased villus height and decreased crypt depth in jejunum (day 21), and thus the villus height to crypt depth ratio (P < 0.01) was increased compared to the NC group on day 42. The serum immunoglobulin M (days 21 and 42), immunoglobulin G (day 42), complement 3 (day 21), and complement 4 (days 21 and 42) were significantly increased (P ≤ 0.02) due to the supplementation of Ple and enramycin, while the concentration of malondialdehyde in jejunum was decreased (P < 0.01) in PC, LPle, and HPle groups on day 21 compared with those in the NC group. Furthermore, Ple reduced (P < 0.01) Escherichia coli and total aerobic bacteria population in ileum and cecum of birds on days 21 and 42. These results indicate that the recombinant plectasin has beneficial effects on growth performance, intestinal health, and innate immunity in broilers.

Transfer of Campylobacter from a Positive Batch to Broiler Carcasses of a Subsequently Slaughtered Negative Batch: A Quantitative Approach

The present study was conducted to quantify Campylobacter cross-contamination from a positive batch of broiler chicken carcasses to a negative batch at selected processing steps and to evaluate the duration of this cross-contamination. During each of nine visits conducted in three broiler slaughterhouses, Campylobacter levels were determined on broiler carcasses originating from Campylobacter-negative batches processed immediately after Campylobacter-positive batches. Data were collected after four steps during the slaughter process (scalding, plucking, evisceration, and washing) at 1, 10, and 20 min after the start of the slaughter of the batches. Campylobacter levels in ceca of birds from Campylobacter-positive batches ranged from 5.62 to 9.82 log CFU/g. When the preceding positive batch was colonized at a low level, no (enumerable) carcass contamination was found in a subsequent negative batch. However, when Campylobacter levels were high in the positive batch, Campylobacter was found on carcasses of the subsequent negative batch but at levels significantly lower than those found on carcasses from the preceding positive batch. The scalding and the evisceration process contributed the least (< 1.5 log CFU/g) and the most (up to 4 log CFU/ g), respectively, to the Campylobacter transmission from a positive batch to a negative batch. Additionally, the number of Campylobacter cells transferred from positive to negative batches decreased over the first 20 min of sampling time. However, the reduction was slower than previously estimated in risk assessment studies, suggesting that pathogen transfer during crosscontamination is a complex process.

Dietary Encapsulated Glycine Influences Clostridium perfringens and Lactobacilli Growth in the Gastrointestinal Tract of Broiler Chickens 3

Three experiments were conducted to determine whether there is a causative relation between dietary glycine concentration and intestinal Clostridium perfringens growth in broiler chickens. Expt. 1 showed that glycine concentrations were higher (P < 0.05) in jejunum and ileum of birds fed fat-encapsulated glycine compared with crystalline glycine. In Expt. 2, 2 cages of 6 birds were assigned to 1 of 6 experimental diets formulated to contain 7.6 and 10.6, 17.8 and 40.6, 27.8 and 30.6, 37.8 and 20.6, 47.7 and 10.6, and 7.8 and 50.6 g/kg total glycine and proline, respectively, provided primarily by supplementation with encapsulated glycine or proline as required. In Expt. 3, 12 groups of 6 birds were fed 4 different diets supplemented with encapsulated glycine to achieve 7.6, 21.0, 34.3, or 47.7 g/kg total glycine. The birds were orally challenged with C. perfringens type A on d 1 and d 14–21 and killed on d 28. In Expt. 2, C. perfringens populations were higher (P < 0.05) in ileum and cecum of birds, which received either 37.8 or 47.7 g/kg total glycine compared with those fed 7.6 g/kg glycine. In Expt. 3, C. perfringens numbers were higher (P < 0.05) in ileum of birds fed either 34.3 or 47.7 g/kg dietary glycine than those given either 7.6 or 21.0 g/kg glycine. Conversely, lactobacilli counts in ileum and cecum were significantly lower in birds fed the higher levels of glycine in both experiments. High C. perfringens colonization and high intestinal lesion scores were associated with reduced performance (P < 0.05). We conclude that glycine is an important determinant of C. perfringens growth in the intestinal tract of broiler chickens.

Decomposition of Nitrogenous Compounds by Intestinal Bacteria in Hummingbirds

Abstract Degradation of urinary nitrogen-containing compounds by bacteria in the ceca of birds occurs in a number of herbivorous and omnivorous species, and cecal absorption of the products of that degradation has been reported in chickens. This recycling of nitrogen may play an important role in nitrogen balance, especially in those species with low dietary nitrogen intake. We report, for the first time, degradation of nitrogenous compounds by intestinal bacteria in a bird that is nectarivorous and lacks ceca, Anna's Hummingbird (Calypte anna). Hummingbirds subsist year-round on a liquid diet with an exceptionally low-nitrogen content. Ureteral urine containing ammonia, urea, and uric acid has been observed in the lower intestinal tract of Anna's Hummingbird. Bacteria obtained from intestinal contents and homogenates of the anterior and posterior intestine of this species were able to break down uric acid, urea, and potassium urate, but not sodium urate. This degradation is the necessary first step in the recycling of nitrogen. Assessing its significance will involve determining whether the products of microbial breakdown are subsequently absorbed across the intestinal walls of these unique animals.

Effect of Lactose and Lactobacillus acidophilus on the Colonization of Salmonella enteritidis in Chicks Concurrently Infected with Eimeria tenella

The effect of dietary lactose and Lactobacillus acidophilus on the colonization of Salmonella enteritidis (phage type 4) in newly hatched leghorn chicks concurrently infected with Eimeria tenella was studied. There were six groups of birds in each of two replicate trials: uninfected controls, birds infected with S. enteritidis, birds infected with S. enteritidis and E. tenella, birds infected with S. enteritidis and E. tenella that were fed with dietary lactose (5%), birds infected with S. enteritidis and E. tenella that were provided with L. acidophilus, and birds infected with S. enteritidis and E. tenella that were fed both L. acidophilus and dietary lactose (5%). Chickens were necropsied at 2, 5, and 8 days after S. enteritidis inoculation for bacteriological examination. The cecal population of S. enteritidis was significantly increased by infection with E. tenella. Lactose alone and the combination of lactose and L. acidophilus significantly reduced the population of S. enteritidis in the ceca of birds infected with E. tenella (P < 0.05), but the combination was more effective than lactose alone (P < 0.05). Adding anaerobic culture of L. acidophilus alone did not significantly decrease the population of S. enteritidis in the ceca. No significant reduction of colonization of S. enteritidis in the liver and spleen of birds with coccidiosis was observed.

Oocysts of Eimeria in the Litter of Broilers Reared to Eight Weeks of Age Before and After Withdrawal of Lasalocid or Salinomycin

Forty-six broiler houses were examined for the presence of oocysts of Eimeria in the litter before and after withdrawal of lasalocid or salinomycin from the feed. A decrease in number of small oocysts (Eimeria acervulina or Eimeria mitis) was observed following withdrawal of medication Numbers of medium-sized oocysts (probably Eimeria tenella) remained the same, but an increase in large oocysts (Eimeria maxima) was recorded. No lesions attributable to Eimeria tenella were found in the ceca of birds after withdrawal of the drug. More small- and medium-sized oocysts were found at sites with new litter than at sites where the litter had been employed for previous flocks. No difference in the number of oocysts was found, whether birds were reared on oak shavings or a mixture of pine shavings and rice hulls. The number of oocysts was positively correlated with the moisture content of the litter, but there was no correlation between oocysts present and the final BW or feed conversion of the birds. Moisture levels were highest (after withdrawal of drug) for new litter or oak shavings. There was no correlation between moisture content of the litter and BW or feed conversion.

Effects of dietary fiber and diet diversity on digestive organs of captive Mallards (Anas platyrhynchos)

We studied the effects of dietary fiber, of plant versus animal diets, and of diet diversity on the digestive organ morphology of captive Mallards (Anas platyrhynchos). Four experimental diets were used: whole corn (low fiber, plant), trout chow (low fiber, primarily animal), rabbit chow (high fiber, plant), and a diverse diet consisting of each of the preceding diets fed daily in random order. Every 5 days for 25 days, we sampled birds from each diet group (N = 6–8) and weighed each bird and its abdominal fat, gizzard, ceca, small intestine, and liver, and then measured its ceca and small intestine length. Other than differences explained by their different body sizes, the sex of the birds had no effect on gut measurements. Changes in body weight and abdominal fat weight suggested that Mallards existed equally well on each of the four diets, presumably because changes in their digestive organs allowed them to have similar digestive efficiencies when eating different diets. Birds on the high fiber diet had the largest digestive organs, but birds on all diets showed changes in digestive organs. The diverse diet produced effects on digestive organ morphology similar to those of the two low-fibre diets. Except for a larger gizzard for macerating corn in birds on that diet, there was no difference in the digestive organs between birds eating animal foods and those eating low fiber plant foods. The maximum weight of gizzard, intestine, and ceca of birds on the high fiber diet was reached in 10 days. However, ceca and intestine lengths of these birds were still increasing after 25 days. This observation suggests that birds can continue to respond to a change in diet after limits to the mass of their digestive organs have been reached.

The Role of Streptococcus faecalis in the Antibiotic Growth Effect in Chickens

MANY workers have attempted to find a correlation between the antibiotic growth effect and the presence or absence of certain bacterial types in the intestinal tract. The microorganism most often implicated has been Clostridium welchii. Thus, Sieburth et al. (1951) found C. welchii in the cecal contents of turkey poults on normal rations. These were virtually eliminated by feeding 15 p.p.m. oxytetracycline. Lev et al. (1957) found C. welchii in the ceca of birds in infected, but not in uninfected quarters. Lev and Forbes (1959) reported that C. welchii depressed growth of germ-free birds. This depression was reversed when penicillin was fed. Other organisms have also been reported to decrease in numbers when antibiotics were fed. Dixon and Thayer (1951), Anderson et al. (1952), and Sieburth et al. (1954), reported decreases in numbers of enterococci in birds fed antibiotics. Slinger et al. (1954) associated the presence of enterococci in the…