The Intestinal Microflora of Hens as Influenced by Various Carbohydrates in a Biotin-deficient Ration

Effects of Dietary Quinoa Seeds on Cecal Microorganisms and Muscle Fatty Acids of Female Luhua Chickens

To study the effects of adding quinoa seed (raw grain) to the diet of the Luhua chicken on the cecal microorganism abundance and fatty acid composition of muscle, 120 49-day-old healthy female dewormed Luhua chickens (body weight 1476.21 ± 101.39 g) were randomly divided into 4 groups, with 3 replicates in each group and 10 chickens in each repetition. The control group (CK group) was fed a basal diet and the experimental groups were fed with 4% (Q4), 8% (Q8), and 12% (Q12) quinoa seed (raw grain) added to the basal diet for 75 days. After 121 days of age, the animals were slaughtered and the 16S rRNA characteristics of cecal flora, as well as composition and content of fatty acids in muscle, were determined and analyzed. The content of unsaturated fatty acids (UFAs), docosahexaenoic acid (C22:6n3; DHA) and n-3 polyunsaturated fatty acids (n-3 PUFAs) in the breast and leg muscles significantly increased in the experimental groups supplemented with quinoa seeds (p < 0.05). However, the content of saturated fatty acids (SAFs) and ratio of n-6/n-3 in breast muscle and leg muscle significantly decreased (p < 0.05). In addition, adding a certain percentage of quinoa seeds in the diet can also affect the community composition and content of microorganisms in the ceca of Luhua chickens. At the phylum level, the Proteobacteria, Actinobacteria, Synergistetes and Melainabacteria in experimental groups (Q4, Q8 and Q12) were significantly lower than those in the CK group (p < 0.05). At the genus level, Desulfovibrio, Synergistes, Olsenella, Parabacteroides, Mailhella, Sutterella and Ruminiclostridiu in group Q4 were significantly lower than those in group CK (p < 0.05) while Faecalibacterium in Q8 group, and Lawsonia and Faecalibacterium in Q12 group were significantly higher than those in the CK group (p < 0.05). Enrichment analysis of the microbial function showed that compared with the CK group, Metabolism and Enzyme Families were significantly enriched in the Q4 group (p < 0.05). Cellular Processes and Signaling were significantly enriched in the Q8 group (p < 0.05). The association analysis of fatty acids with microorganisms showed that the abundance of Faecalibacterium, Lawsonia and Meagmonas was significantly correlated with partial SFAs and UFAs (p < 0.05). In conclusion, adding quinoa seeds to diets significantly increased the content of muscle DHA, UFAs and n-3 PUFAs. The content of SAFs and the n-6/n-3 ratio were significantly reduced. Taken together, quinoa can effectively improve the cecal microbiota structure, inhibit the number of harmful bacteria and increase the number of beneficial bacteria, regulating the intestinal environment and promoting the body health of female Luhua chickens.

Effects of Dietary Oregano Essential Oil on Cecal Microorganisms and Muscle Fatty Acids of Luhua Chickens

This experiment was conducted to investigate the effects of oregano essential oil on the cecal microorganisms and muscle fatty acids of Luhua chickens. One hundred and twenty 49-day-old healthy dewormed Luhua chickens were randomly divided into four groups with three replicates per group and ten chickens per replicate. The corn−quinoa and soybean meal diets were supplemented with 0 (Q8 group), 50 (QO50 group), 100 (QO100 group) and 150 mg·kg−1 (QO150 group) of oregano essential oil, respectively, and the experiment lasted for 75 days. The composition of intestinal flora was detected by Illumina sequencing of the 16S rRNA V4 region, and the composition and content of fatty acids in the muscles were analyzed by gas chromatography. The results showed that dietary oregano essential oil can effectively increase the contents of elaidic acid (C18:ln9t), polyunsaturated fatty acids (PUFAs) and n-3 polyunsaturated fatty acids (n-3 PUFAs) in breast muscle tissues. However, the fatty acid composition and PUFA content in leg muscle tissues were not significantly improved. According to a 16S rRNA high-throughput sequencing analysis, dietary oregano essential oil supplementation with a certain concentration can change the cecal microbial community composition of broilers. At the phylum level, Elusimicrobia in the QO150 group was significantly lower than that in Q8 group (p < 0.05). At the genus level, Phascolarctobacterium, Parasutterella and Bilophila in the experimental groups (QO50, QO100 and QO150) were significantly lower than those in the Q8 group (p < 0.05). An enrichment analysis of the microbial function found that the amino acid metabolism, energy metabolism, metabolism, signal transduction and genetic information processing were mainly enriched in the experimental groups, which promoted the digestion and absorption of nutrients and enhanced intestinal barrier functioning. An analysis of the association between fatty acids and microbes found that the abundance of microbiota was significantly correlated with partially saturated fatty acids (SFAs) and unsaturated fatty acids (UFAs) (p < 0.05). In conclusion, the dietary addition of oregano essential oil can effectively improve cecal microbial community composition, promote the digestion and absorption of nutrients, and enhance intestinal barrier functioning. It can significantly improve the content of some fatty acids, and there was a certain correlation between caecum microorganisms and fatty acid deposition in muscles.

Community composition of cecal microbiota in commercial yellow broilers with high and low feed efficiencies

The cecal microbiota plays important roles in host food digestion and nutrient absorption, which may in part affect feed efficiency (FE). To investigate the composition and functional differences of cecal microbiota between high (n = 30) and low (n = 29) feed conversion ratio (FCR; metric for FE) groups, we performed 16S rRNA gene sequencing and predicted the metagenome function using Phylogenetic Investigation of Communities by Reconstruction of Unobserved Species in yellow broilers. The results showed that the 2 groups had the same prominent microbes but with differing abundance. Firmicutes, Bacteroidetes, and Actinobacteria were 3 prominent bacterial phyla in the cecal microbial community. Although there were no differences in microbial diversity, compositional differences related to FCR were found via linear discriminant analysis (LDA) effect size; the genus Bacteroides had a significantly higher abundance (LDA >2) in the high FE (HFE) group than in the low FE group. Furthermore, genus Bacteroides had a negative FCR-associated correlation (P < 0.05). Oscillospira was positively correlated with Bacteroides in both groups, whereas Dorea was negatively correlated with Bacteroides in the HFE group. Predictive functional analysis revealed that metabolic pathways such as “starch and sucrose metabolism,” “phenylalanine, tyrosine and tryptophan biosynthesis,” and “carbohydrate metabolism” were significantly enriched in the HFE group. The relatively subtle differences in FE-associated cecal microbiota composition suggest a possible link between cecal microbiota and FE. Moreover, Bacteroides may potentially be used as biomarkers for FE to improve growth performance in yellow broilers.

Effects of sorbic acid feed fungistat on the intestinal microflora of floor-reared broiler chickens

The intestinal microflora of a group of broilers fed a diet containing .04% sorbic acid from Days 1 through 49 of their lives was compared with broilers given a diet without the fungistat. Four broilers from each group were killed at 7, 21, 35, and 49 days, and intestinal sections of the duodenum, the lower small intestine, and both ceca were removed aseptically. Samples of the contents of the intestinal sections were analyzed microbiologically. Groups of microorganisms analyzed included total aerobes, total anaerobes, coliforms, streptococci, lactobacilli, clostridia, Bacteroides, Bifidobacterium, yeasts, and molds. Generally, there was a large variation in viable counts of microorganisms for birds of the same treatment. Of the nine groups of microorganisms analyzed the highest counts obtained (greater than 10(6)/g) were for total aerobes, total anaerobes, lactobacilli, and Bifidobacterium. Coliforms, streptococci, and clostridia showed intermediate counts (greater than 10(3)/g), while yeasts and molds and Bacteroides showed the lowest counts (greater than 10(2)/g). Total microbial numbers, in most cases and irrespective of sorbic acid treatment, were highest in the ceca, lower in the small intestine, and still lower in the duodenum. There were no major trends of microbial population changes observed in a given treatment, intestinal location, or group of organisms with age and time on feed. Inclusion of sorbic acid in the feed did not influence total aerobes, total anaerobes, lactobacilli, streptococci, Bifidobacterium, and clostridia. However, broilers on sorbic acid-containing feed had, at 49 days of age, lower coliform counts in the duodenum, lower yeast and mold counts in the ceca, and higher Bacteroides counts in the ceca.

Effect of natural feedstuffs added to a semi-purified diet on Eimeria tenella infection

Experiments were conducted to study the effect of addition of natural feedstuffs to a semi-purified (SP) diet on Eimeria tenella infection of chickens. Chicks were fed the experimental diet throughout the experimental period and were orally inoculated with 200,000 sporulated oocysts of E. tenella at 14 days of age. Addition of corn, but not soybean meal, to a SP diet increased mortality and decreased body weight gain due to the coccidial infection in comparison with chickens fed the SP diet. Addition of corn gluten meal or replacement of poultry fat by corn oil or glucose by corn starch in the SP diet did not significantly change any of the parameters studied. Addition of 20% of corn fermentation solubles (CFS)-but not 20% of distillers dried grains with solubles, wheat bran, or rice bran-to the SP diet, resulted in significantly higher mortality from the coccidial infection. Addition of 5 or 10% of CFS to the SP diet significantly increased mortality in chicks compared to those fed the SP diet, but feeding the residue of CFS after extraction with chloroform-methanol followed by water did not increase mortality. These studies show that corn and CFS contain factors that enhance E. tenella infection in chicks fed a semi-purified diet, but other natural feedstuffs such as soybean meal do not.

Influence of dietary lactose on the gut flora of chicks

1. The gut microflora of chicks fed on a purified diet containing 300 g lactose plus 300 g starch/kg was compared with that of control birds receiving a diet containing 600 g starch/kg. 2. In 14-d-old conventional chicks, lactose in the diet decreased the incidence of lactobacilli and clostridia in the caecal contents, although when presenting lactose-fed chicks the counts of lactobacilli exceeded those of control chicks. 3. High counts of Proteus sp. were present in the caeca of control birds but they were completely suppressed in conventional birds fed on the lactose diet. In vitro tests showed that this inhibition was partially due to Escherichia coli and Streptococcus faecalis. 4. The growth of Lactobacillus acidophilus was inhibited by lactose when gnotobiotic chicks were monoassociated but not when polyassociated. The protective effect was shown in vitro to be due to L. salivarius. 5. The pH was markedly lowered in the caecum of conventional and polyassociated chicks receiving dietary lactose. Of the strains used in gnotobiotic experiments E. coli, S. faecalis and L. salivarius produced the lowest pH values in the caeca.

[Necrotic enteritis in broilers. I. Clinoco-pathological aspect]

This study represents an analysis of the principal clinical factors and pathological lesions of 150 cases of necrotic enteritis encountered during 1968 and 1969 in Quebec. Following multiple investigations no common factor was observed which might have explained the pathogenesis of the condition which was observed during every month of the year, especially from May to November. Birds two to four weeks of age were the most susceptible. The main lesion was a fibrino-necrotic enteritis always localized in the small intestine, either in its entire length or just a segment and characterized by the disappearance of the surface epithelium and necrosis of the villi. The lumen was filled with desquamated epithelial cells and bacteria. Foci of coagulation necrosis were observed in the liver and foci of nephrosis in the kidneys. A Gram+ bacillus, strictly anaerobic, was always isolated from the viscera.