Gastrointestinal Tract Of Cattle Research Articles

Characterization of genes and proteins involved in the absorption of long-chain fatty acids in the gastrointestinal tract of cattle

Characterization of genes and proteins involved in the absorption of long-chain fatty acids in the gastrointestinal tract of cattle

Prevalensi nematoda gastrointestinal pada sapi di Pasar Ternak Payakumbuh

This study aimed to determine the prevalence of Nematoda infection in the gastrointestinal tract of cattle at Payakumbuh Cattle Market. The research was conducted in August 2020. The method used was a survey using purposive sampling. One hundred fifty-five cow dung samples were collected from the Payakumbuh Cattle Market. The fecal examination was performed using the flotation method and sedimentation method. The gastrointestinal nematode was Strongyloides sp, Ostertagia sp., and Trichuris sp. Infection with one roundworm species in 18.46% of cows and 24% of bulls. Infection with two roundworm species in 10% of cows and 20% bulls. Infection with three roundworm species in 2.3% in cows and 4% in bulls. The prevalence of three roundworm species was 0.77% in cows and not found in bulls. The rate of nematode infection in the 0-2-year-old group was 29.16%, and the > two-year-old group was 33.73%. It can be concluded that the average cattle in the Payakumbuh Cattle Market are infected with gastrointestinal nematodes, and severe treatment is needed either by farmers or by involvement from the local government.

Disease Occurrence in- and the Transferal of Zoonotic Agents by North American Feedlot Cattle

North America is a large producer of beef and contains approximately 12% of the world's cattle inventory. Feedlots are an integral part of modern cattle production in North America, producing a high-quality, wholesome protein food for humans. Cattle, during their final stage, are fed readily digestible high-energy density rations in feedlots. Cattle in feedlots are susceptible to certain zoonotic diseases that impact cattle health, growth performance, and carcass characteristics, as well as human health. Diseases are often transferred amongst pen-mates, but they can also originate from the environment and be spread by vectors or fomites. Pathogen carriage in the gastrointestinal tract of cattle often leads to direct or indirect contamination of foods and the feedlot environment. This leads to the recirculation of these pathogens that have fecal-oral transmission within a feedlot cattle population for an extended time. Salmonella, Shiga toxin-producing Escherichia coli, and Campylobacter are commonly associated with animal-derived foods and can be transferred to humans through several routes such as contact with infected cattle and the consumption of contaminated meat. Brucellosis, anthrax, and leptospirosis, significant but neglected zoonotic diseases with debilitating impacts on human and animal health, are also discussed.

Administration of probiotic lactic acid bacteria to modulate fecal microbiome in feedlot cattle

Modulation of animal gut microbiota is a prominent function of probiotics to improve the health and performance of livestock. In this study, a large-scale survey to evaluate the effect of lactic acid bacteria probiotics on shaping the fecal bacterial community structure of feedlot cattle during three experimental periods of the fattening cycle (163 days) was performed. A commercial feedlot located in northwestern Argentina was enrolled with cattle fed mixed rations (forage and increasing grain diet) and a convenience-experimental design was conducted. A pen (n = 21 animals) was assigned to each experimental group that received probiotics during three different periods. Groups of n = 7 animals were sampled at 40, 104 and 163 days and these samples were then pooled to one, thus giving a total of 34 samples that were subjected to high-throughput sequencing. The microbial diversity of fecal samples was significantly affected (p < 0.05) by the administration period compared with probiotic group supplementation. Even though, the three experimental periods of probiotic administration induced changes in the relative abundance of the most representative bacterial communities, the fecal microbiome of samples was dominated by the Firmicutes (72–98%) and Actinobacteria (0.8–27%) phyla, while a lower abundance of Bacteroidetes (0.08–4.2%) was present. Probiotics were able to modulate the fecal microbiota with a convergence of Clostridiaceae, Lachnospiraceae, Ruminococcaceae and Bifidobacteriaceae associated with health and growth benefits as core microbiome members. Metabolic functional prediction comparing three experimental administration periods (40, 104 and 163 days) showed an enrichment of metabolic pathways related to complex plant-derived polysaccharide digestion as well as amino acids and derivatives during the first 40 days of probiotic supplementation. Genomic-based knowledge on the benefits of autochthonous probiotics on cattle gastrointestinal tract (GIT) microbiota composition and functions will contribute to their selection as antibiotic alternatives for commercial feedlot.

Progressive microbial adaptation of the bovine rumen and hindgut in response to a step-wise increase in dietary starch and the influence of phytogenic supplementation.

Microbial composition and activity in the gastrointestinal tract (GIT) of cattle has important implications for animal health and welfare, driving the focus of research toward ways to modify their function and abundance. However, our understanding of microbial adaption to nutritional changes remains limited. The aim of this study was to examine the progressive mechanisms of adaptation in the rumen and hindgut of cattle receiving increasing amounts of starch with or without dietary supplementation of a blended phytogenic feed additive (PFA; containing menthol, thymol and eugenol). We used 16S rRNA gene amplicon sequencing to assess the microbial composition and predicted metabolic pathways in ruminal solid and liquid digesta, and feces. Furthermore, we employed targeted liquid chromatography-mass spectrometry methods to evaluate rumen fluid metabolites. Results indicated a rapid microbial adaptation to diet change, starting on the second day of starch feeding for the particle associated rumen liquid (PARL) microbes. Solid rumen digesta- and feces-associated microbes started changing from the following day. The PARL niche was the most responsive to dietary changes, with the highest number of taxa and predicted pathways affected by the increase in starch intake, as well as by the phytogenic supplementation. Despite the differences in the microbial composition and metabolic potential of the different GIT niches, all showed similar changes toward carbohydrate metabolism. Metabolite measurement confirmed the high prevalence of glucose and volatile fatty acids (VFAs) in the rumen due to the increased substrate availability and metabolic activity of the microbiota. Families Prevotellaceae, Ruminococcaceae and Lachnospiraceae were found to be positively correlated with carbohydrate metabolism, with the latter two showing wide-ranging predicted metabolic capabilities. Phytogenic supplementation affected low abundant taxa and demonstrated the potential to prevent unwanted implications of feeding high-concentrate diet, such as reduction of microbial diversity. The inclusion of 50% concentrate in the diet caused a major shift in microbial composition and activity in the GIT of cattle. This study demonstrated the ability of microorganisms in various GIT niches to adjust differentially, yet rapidly, to changing dietary conditions, and revealed the potential beneficial effects of supplementation with a PFA during dietary adaptation.

Detection of Verocytotoxin-Producing Escherichia Coli in Raw and Fermented (Nono) Milk in Sokoto Metropolis, Sokoto State, Nigeria.

Verocytotoxin-producing Escherichia coli (VTEC) also called Shiga toxin producing Escherichia coli (STEC), are food borne organisms which cause fatal disease in human. The bacteria are frequently found in cattle gastrointestinal tract with high potential of contaminating animal products such as milk, meat, and cheese. A cross-sectional study was conducted to investigate the prevalence of VTEC and to detect the presence of stx1, stx2, and eaeA genes in raw and fermented milk sold within sokoto metropolis.Milk samples were analysed using bacterial culture, biochemical test and PCR for molecular identification. Bacteriological culture and biochemical characterization produced Escherichia coli with detection rate 0f 16.0% (38/238). Molecular identification of isolates by Polymerase chain reaction revealed 47.4% (18/38) detection rate of VTEC. The total prevalence of VTEC in the study was 7.6% (18/238), with proportion of raw and fermented milk were 12.5% (13/104) and 3.7% (5/134). There was no association (P≥ 0.05) between VTEC and different milk types. Amplification of isolate by mPCR using specific primers stx1, stx2, and eaeA gene confirmed that (94.4% (17) harboured stx2 and 1 (5.6%) harboured stx1 and eaeA genes.The study established prevalence of VTEC in raw and fermented milk consumed within sokoto metropolis, and presence of stx1, stx2 and eaeA gene. These findings indicate potential faecal contamination of the milk with VTEC in raw and fermented milk. Veterinary services in the state should educate farmers on the importance of farm hygiene and enlighten the Hausa/Fulani nomad and public on the danger associated with the consumption of contaminated milk.

Prevalence of Helminthic Infections in the Gastrointestinal Tract of Cattle in Mazandaran Province (Northern Iran).

Ruminant parasites are found in all parts of the world, including the tropical and subtropical regions. Mazandaran province (northern Iran) is one of the areas prone to the activity of gastrointestinal parasites in ruminants. This study was performed in 2020, in order to identify common parasites of cattle gastrointestinal tract, the percentage of the infection, the effect of seasons, and livestock on the amount of infection and determine the severity of infection. In this study, seven genera of gastrointestinal parasites including Strongyloides, Haemonchus, Ostertagia, Cooperia, Trichostrongylus, Oesophagostomum, and Chabertia were identified among 240 cattle. Overall, 34.58% of cows were infected with different kinds of parasites. Based on the average percentage of livestock infected with gastrointestinal parasites across different seasons, winter had the lowest percentage (18.33%) compared to other seasons, which has a statistically significant difference (P < 0.05). Also, we observe that the female cattle's infection rate, in comparison with males, had no significant difference (P < 0.05). Moreover, 67.17% of the cattle had a moderate level of infection. Despite the fact that farmers use antiparasitic drugs, helminthic infections in cattle are still high. In conclusion, the lack of proper implementation of helminthic infection control programs as well as antiparasitic drug resistance in this area can be a key element for the high prevalence of livestock helminthic infection in these areas.

The Dynamics of Chromatin Accessibility Prompted by Butyrate-Induced Chromatin Modification in Bovine Cells

Butyrate is produced by microbe fermentation in the rumen, and its supplementation results in rumen development. Butyrate-induced experiments are valuable in studying nutrient metabolism, cell growth, and functional genomics. This study aimed to characterize accessible chromatin regions and the dynamics of genomic accessibility prompted by butyrate-induced histone modifications in bovine cells. An average of 117,569 accessible chromatin regions were identified for all samples, and 21,347 differentially accessible regions (DARs) for butyrate. Most of the DARs were in distal intergenic regions, introns, and promoters. Gene ontology enrichment resulted in important terms related to the digestive system, regulation of epithelial cells, and cell adhesion. Ingenuity Pathway Analysis (IPA) identified critical networks (e.g., digestive system development, cell morphology and assembly, and cell cycle); canonical pathways (e.g., TGFβ, Integrin-linked kinase, and epithelial adherens junction); and upstream regulators (e.g., TGFβ1, FOS, JUNB, ATF3, and KLFs). Co-expression analysis further showcased the TGFβ and Integrin-linked kinase (ILK)-signaling pathways, which play roles in rumen development through cellular adhesions. This study is the first to provide a genome-wide characterization of differential, open chromatin regions for bovine cells by butyrate-induced treatment. These results provide valuable information for future studies of the butyrate functions in cattle gastrointestinal tract development.

Escherichia coli and Pseudomonas aeruginosa Isolated From Urine of Healthy Bovine Have Potential as Emerging Human and Bovine Pathogens.

The study of livestock microbiota has immediate benefits for animal health as well as mitigating food contamination and emerging pathogens. While prior research has indicated the gastrointestinal tract of cattle as the source for many zoonoses, including Shiga-toxin producing Escherichia coli and antibiotic resistant bacteria, the bovine urinary tract microbiota has yet to be thoroughly investigated. Here, we describe 5 E. coli and 4 Pseudomonas aeruginosa strains isolated from urine of dairy Gyr cattle. While both species are typically associated with urinary tract infections and mastitis, all of the animals sampled were healthy. The bovine urinary strains were compared to E. coli and P. aeruginosa isolates from other bovine samples as well as human urinary samples. While the bovine urinary E. coli isolates had genomic similarity to isolates from the gastrointestinal tract of cattle and other agricultural animals, the bovine urinary P. aeruginosa strains were most similar to human isolates suggesting niche adaptation rather than host adaptation. Examination of prophages harbored by these bovine isolates revealed similarity with prophages within distantly related E. coli and P. aeruginosa isolates from the human urinary tract. This suggests that related urinary phages may persist and/or be shared between mammals. Future studies of the bovine urinary microbiota are needed to ascertain if E. coli and P. aeruginosa are resident members of this niche and/or possible sources for emerging pathogens in humans.

Efficacy of a commercial fungal formulation containing Duddingtonia flagrans (Bioverm®) for controlling bovine gastrointestinal nematodes.

Bioverm® (Duddingtonia flagrans) is a fungal formulation indicated for controlling gastrointestinal nematodes in ruminants and horses, which has recently been authorized for commercialization in Brazil. The objective was to determine the efficiency of Bioverm® against larvae of gastrointestinal nematodes after passage through the gastrointestinal tract of cattle. Twelve animals were used, divided into two groups. In the treated group, a single dose of 1 g of Bioverm® per 10 kg of live weight (containing 105 chlamydospores of D. flagrans) was provided for each animal. Fecal samples were obtained from the animals in each group at 12, 24, 36, 48, 60 and 72 hours after administration. In assay A, 2 g of feces were added to Petri dishes containing 2% agar-water medium. In assay B, coprocultures were performed. In both assays, the peak of larval predation occurred within 48 hours after administration of Bioverm®. In assay A, a significant larval reduction (P < 0.05) was seen at 48 h (88.2%). In assay B, significant reductions (P < 0.05) were seen at 36 h (43.7%) and 48 h (82.3%). Bioverm® showed high predatory capacity after passage through the gastrointestinal tract of cattle and was effective for controlling gastrointestinal nematodes.

Route of administration influences the concentration of ivermectin reaching nematode parasites in the gastrointestinal tract of cattle

An animal trial was conducted to measure the concentrations of ivermectin occurring in abomasal and small intestinal contents and mucosa, and in the target parasites (Ostertagia ostertagi and Cooperia oncophora) following administration by subcutaneous, oral and pour-on routes. Twenty-five steers were infected with ivermectin-resistant isolates of O. ostertagi and C. oncophora and following patency randomly allocated to 3 treatment groups of 7 and 1 untreated control group of four. On day 0, animals in the treatment groups were administered ivermectin via the oral, injectable or pour-on routes. On days 1, 2, 3, 4, 5, 6 and 8, blood samples were collected from all live animals, one animal from each treatment group was euthanised and the abomasum and small intestine recovered. Control animals were euthanised on each of days 4, 5, 6 and 8. Samples of gastrointestinal tract organs, their contents, mucosa and parasites were collected and assayed for ivermectin concentration using HPLC. The highest plasma concentrations occurred following subcutaneous administration. In the gastrointestinal contents the highest levels occurred following oral administration, although one high value occurred following pour-on administration, which was attributed to self-licking by the treated animal. The lowest GI content levels followed subcutaneous injection. Ivermectin concentrations in the gastrointestinal mucosa were highest following subcutaneous injection. Drug levels in the abomasal parasite O. ostertagi were most closely correlated with levels in the abomasal mucosa whereas levels in the intestinal C. oncophora were most closely correlated with those in the intestinal contents. Thus, the maximun levels of drug reached C. oncophora in the small intestine following oral administration. In contrast, the highest levels of ivermectin in O. ostertagi followed subcutaneous injection. Therefore, route of administration is likely to influence the exposure to ivermectin for different parasite species.

Arthrobotrys cladodes and Pochonia chlamydosporia: Nematicidal effects of single and combined use after passage through cattle gastrointestinal tract

Nematodiosis are responsible for financial losses in cattle production systems due to treatment costs, falling production rates and animal deaths. The incorporation of sodium alginate pellets containing nematophagous fungi in the bovine diet is a method for the control of nematodiosis. The aims of this study were to evaluate the viability of Arthrobotrys cladodes and Pochonia chlamydosporia contained in sodium alginate pellets after passage through the bovine gastrointestinal tract, as well as to evaluate the effects of single and combined use of these fungi against bovine parasitic nematodes. The reduction in parasitic nematode infective larvae of bovines by the combined use of Arthrobotrys cladodes and Pochonia chlamydosporia was more than the reduction in infective larvae by Arthrobotrys cladodes or Pochonia chlamydosporia alone in the collections 12, 24 and 36 h after giving the pellets to the animals. Arthrobotrys cladodes and Pochonia chlamydosporia combined promoted maximum reduction of infective larvae of 86.3%. Therefore, the combination of Arthrobotrys cladodes and Pochonia chlamydosporia may be an effective method to control gastrointestinal nematodiosis affecting grazing cattle.

In Vitro Study of “Protected Fats” Based on Lecithin and Calcium Alginate

Background: Today, the urgent tasks of feeding cattle is to increase milk yield, increase the fat content in milk, and improve the quality of other animal products. However, the recommended amount of fat is not enough during calving and during lactation of cows. This leads to the fact that the fat content of milk is reduced by 30%. The aim of the study : To study the behavior of encapsulated fats in model media corresponding to the gastrointestinal tract of cattle. Materials and methods: The study was conducted by direct gravimetric analysis using a Programix TX 50 muffle furnace. As model media for the gastrointestinal tract of cattle, standard pH titers were used, adjusted to the required pH value with 0.1 M solutions of hydrochloric acid/sodium hydroxide. Results: After analyzing the data obtained, it was found that in a slightly alkaline medium (pH range 7.4–7.8), the time for complete release of phospholipids is 12 hours. During experiment No. 2, the behavior of “protected fats” was revealed in model environments corresponding to physiological parameters of the gastrointestinal tract of cattle. The equivalent amount of phosphorus to phospholipids was 11.90%, which corresponds to a proportion of the liberated phospholipids of higher fatty acids equal to 97.30%. Conclusion: “Protected fats” reach the model environment of the small intestines of ruminants in an unchanged form, where capsule disintegration is observed, followed by the release of the phospholipid mixture. Full release of the encapsulated mixture in a slightly alkaline medium (pH 7.4–7.8) is achieved within 12 hours.

An Overview of the Elusive Passenger in the Gastrointestinal Tract of Cattle: The Shiga Toxin Producing Escherichia coli.

For approximately 10,000 years, cattle have been our major source of meat and dairy. However, cattle are also a major reservoir for dangerous foodborne pathogens that belong to the Shiga toxin-producing Escherichia coli (STEC) group. Even though STEC infections in humans are rare, they are often lethal, as treatment options are limited. In cattle, STEC infections are typically asymptomatic and STEC is able to survive and persist in the cattle GIT by escaping the immune defenses of the host. Interactions with members of the native gut microbiota can favor or inhibit its persistence in cattle, but research in this direction is still in its infancy. Diet, temperature and season but also industrialized animal husbandry practices have a profound effect on STEC prevalence and the native gut microbiota composition. Thus, exploring the native cattle gut microbiota in depth, its interactions with STEC and the factors that affect them could offer viable solutions against STEC carriage in cattle.

The effect of tylosin on antimicrobial resistance in beef cattle enteric bacteria: A systematic review and meta-analysis

BackgroundTylosin is a commonly used in-feed antimicrobial and is approved in several countries to reduce the incidence of liver abscesses in beef cattle. Macrolides are critically important antimicrobials in human health and used to treat some foodborne bacterial diseases, such as Campylobacter jejuni and Salmonella. Feeding tylosin could select for resistant enteric bacteria in cattle, which could contaminate beef products at slaughter and potentially cause foodborne illness. We conducted a systematic review and meta-analysis to evaluate the impact of feeding tylosin to cattle on phenotypic and genotypic resistance in several potential zoonotic enteric bacteria: Enterococcus species, Escherichia coli, Salmonella enterica subspecies enterica, and Campylobacter species. This review was registered with PROSPERO (#CRD42018085949). ResultsEleven databases were searched for primary research studies that fed tylosin at approved doses to feedlot cattle and tested bacteria of interest for phenotypic or genotypic resistance. We screened 1,626 citations and identified 13 studies that met the inclusion criteria. Enterococcus species were tested in seven studies, Escherichia coli was isolated in five studies, three studies reported on Salmonella, and two studies reported on Campylobacter species. Most studies relied on phenotypic antimicrobial susceptibility testing and seven also reported resistance gene testing. A random-effects meta-analyses of erythromycin-resistant enterococci from four studies had significant residual heterogeneity. Only two studies were available for a meta-analysis of tylosin-resistant enterococci. A semi-quantitative analysis demonstrated an increase in macrolide-resistant enterococci after long durations of tylosin administration (>100 days). Semi-quantitative analyses of other bacteria-antimicrobial combinations revealed mixed results, but many comparisons found no effect of tylosin administration. However, about half of these no-effect comparisons did not record the cumulative days of tylosin administration or the time since the last dose. ConclusionsWhen fed at approved dosages for typical durations, tylosin increases the proportion of macrolide-resistant enterococci in the cattle gastrointestinal tract, which could pose a zoonotic risk to human beef consumers. Feeding tylosin for short durations may mitigate the impact on macrolide-resistant enterococci and further studies are encouraged to determine the effect of minimizing or eliminating tylosin use in beef cattle. There may also be an impact on other bacteria and other antimicrobial resistances but additional details or data are needed to strengthen these comparisons. We encourage authors of antimicrobial-resistance studies to follow reporting guidelines and publish details of all comparisons to strengthen future meta-analyses.

Specific composition of indigenous microflora (Lactobacillus spp., Bifidobacterium spp., Lactococcus spp.) in farm animals

To maintain a stable composition of the gastrointestinal tract microflora in farm animals it is necessary to use probiotic agents to ensure the full functioning of the digestive, hormonal, and immune systems of the body. Most modern probiotics include lactic acid bacteria and bifidobacteria, which are the most physiologically valuable components of a healthy organism’s an indigenous microflora. The aim of this study was to provide indication and identification from the milk of healthy cows and gastric tract of healthy pigs and calves of the genus bacteria Lactobacillus, Bifidobacterium, and Lactococcus. The objects of research were cultures of microorganisms isolated from cows milk (82), the gastrointestinal tract of cattle (317), and piglets of different age groups (114). Bacteriological studies were carried out on the basis of the veterinary sanitation and parasitology laboratory of the National Scientific Center "Institute of Experimental and Clinical Veterinary Medicine" (Kharkiv) in accordance with current regulatory documents. According to the research of the gastrointestinal tract of clinically healthy calves and piglets isolated and typified to 317 and 114 cultures of microorganisms, the species composition of the microflora (82 bacterial cultures) of the cisternous and parenchymatous milk of clinically healthy cows was determined. A total of 513 isolates of microorganisms were isolated, including: Enterobacter spp. –2 (0,39%), Staphylococcus spp. – 7 (1,37%), Bacillus spp. – 11 (2,14%), Enterococcus spp. – 33 (6.43%), Lactococcus spp. – 75(14,62%), Bifidоbacterium spp. – 170 (33,14%), and Lactobacillus spp. – 215 (41,91%). In the study of the biological properties of isolated microorganisms Lactobacillus spp. (215) established their species identity: L. brevis – 7 (3.26%), L. delbrueckii – 9 (4,19%), L. acidophilus – 21 (9,77%), L. fermentum – 23 (10,69%), L. casei – 57 (26,51%), and L. plantarum – 98 (45.58%). Cultures of Bifidobacterium spp. (170) belong to B. suis – 2 (1,18%), B. breve – 7 (4,12%), B. lactentis – 15 (8,82%), B. bifidum – 21 (12,35%), B. longum – 22 (12,94%), B. infantis – 25 (14,71%), and B. adolescentis – 78 (45,88%). From samples of biological material of farm animals, 75 cultures of the genus Lactococcus spp. were isolated (75) of which Lactococcus lactis is representative. Isolated bacteria Lactobacillus spp., Bifidobacterium spp. and Lactococcus spp. promising when creating innovative probiotic products for farm animals.

Изменения микробиоценоза рубца, крови и переваримость сухого вещества рациона при введении бычкам совместно ϲ жировой добавкой ультрадисперсных частиц железа

Abstract. The gastrointestinal tract of cattle is a large and complex biomechanism for processing substances coming from outside, with their further assimilation by the animal’s body, to ensure normal life and productive growth. A special role is played by the rumen of cattle, in which the biosynthetic processes of the conversion of some chemicals and elements to others, under the action of enzymes of microorganisms, which have a responsible role in the processing of food components, as well as in a symbiotic relationship to each other. So, a disruption in the work of certain microorganisms under the influence of food factors leads to a disruption in the synthesis and work of the rest of the microbiota, which generally affects the state of the animal bioreactor as a whole. The aim of the study was to establish the effect of various dosages of ultrafine particles of Fe in combination with a fat supplement, as part of rations on the digestibility of dry matter of the feed, basic indicators of scar content, such as microbial fermentation of the feed and biomass of microorganisms and fatty acid composition. The scientific novelty of the work lies in the fact that the effect of a complex of ultrafine particles of iron of different dosages ϲ a fat supplement on the cicatricial digestion of bulls raised for meat was studied. Methodology and methods. To conduct research, 12 bulls were bred in the conditions of the Pokrovskiy agricultural college-branch of the Orenburg State Agrarian University of the Orenburg region of the Orenburg region. Of these, four groups were selected according to the principle of analogues – control and three experimental, three animals in each, which, according to A. A. Aliyev were imposed scar fistulas. Results and scope. Thus, during the experiment it was found that the optimal dosage of iron nanoparticles mixed with a fat supplement in the diet was 425.6 mg per head per day, which contributes to better digestibility of dry matter by 8.98 % and a higher content of VFA in scar fluid by 2.28 % compared to ϲ control.

Effect of oak bark extract (Quercus cortex) and a complex of substances inhibitors Quorum sensing on metabolic processes occurring in the gastrointestinal tract of cattle

Effect of oak bark extract (Quercus cortex) and a complex of substances inhibitors Quorum sensing on metabolic processes occurring in the gastrointestinal tract of cattle

Quantification of Bacteria Indicative of Fecal and Environmental Contamination from Hides to Carcasses.

Fecal bacteria, which reside in the gastrointestinal tract of cattle, can contaminate beef carcasses during processing. In beef cattle slaughter plants, the presence and concentrations of generic Escherichia coli, coliforms, Enterobacteriaceae (EB), and total aerobic bacteria are monitored as indicator organisms of fecal and environmental contamination. The objectives of this study were as follows: (1) to determine the concentrations of generic E. coli, coliforms, EB, and aerobic bacteria on beef carcasses at different processing points in Midwestern commercial beef slaughter plants during the summer, spring, and fall seasons; and (2) to estimate bacterial transfer on carcasses during the hide removal and evisceration processes. Hide and carcass surface sample swabs were collected from slaughtered cattle at four large commercial processing plants. At each plant visit (3 visits to each of the 4 plants) and during 3 seasons, 20 samples were collected at 5 points: hide-on (hide of animal near exsanguination pit), hide-off carcass, pre-evisceration carcass, postevisceration carcass, and postintervention carcass, for a total of 3600 samples. Bacterial concentrations were determined using 3M™ Petrifilm™ plates. Associations between season and processing plant with concentrations of E. coli, coliforms, EB, and total aerobic bacteria, overall, between hide-on and hide-off, and between pre- and post-evisceration, were evaluated using multilevel mixed-effects linear regression models. Bacterial concentrations on beef carcasses significantly decreased throughout processing. Moreover, hide removal was an important source of carcass contamination, given bacterial concentrations detected on hide-off carcass samples were the highest, and bearing in mind that carcass muscle surfaces should be sterile. Results from this study indicate that the interventions applied by the processing plants were effective, as they probably contributed to the significant reduction of bacterial concentrations of carcasses.

Transcriptomic analysis reveals specific metabolic pathways of enterohemorrhagic Escherichia coli O157:H7 in bovine digestive contents

BackgroundThe cattle gastrointestinal tract (GIT) is the main enterohemorrhagic Escherichia coli (EHEC) reservoir. In order to identify nutrients required for the survival or multiplication of EHEC in the bovine GIT, we compared the transcriptomes of the EHEC O157:H7 reference strain EDL933 cultured in vitro in bovine digestive contents (DCs) (rumen, small intestine and rectum) using RNA-sequencing.ResultsGene expression profiles showed that EHEC EDL933 activated common but also specific metabolic pathways to survive in the different bovine DCs. Mucus-derived carbohydrates seem important in EHEC nutrition in posterior DCs (small intestine and rectum) but not in rumen content. Additional carbohydrates (xylose, ribose, mannitol, galactitol) as well as gluconeogenic substrates (aspartate, serine, glycerol) would also be used by EHEC as carbon and/or nitrogen sources all along the bovine GIT including the rumen. However, xylose, GalNac, ribose and fucose transport and/or assimilation encoding genes were over-expressed during incubation in rectum content compared with rumen and intestine contents, and genes coding for maltose transport were only induced in rectum. This suggests a role for these carbohydrates in the colonization of the cattle rectum, considered as the major site for EHEC multiplication. In contrast, the transcription of the genes associated with the assimilation of ethanolamine, an important nitrogen source for EHEC, was poorly induced in EHEC growing in rectum content, suggesting that ethanolamine is mainly assimilated in the cattle rumen and small intestine. Respiratory flexibility would also be required for EHEC survival because of the redundancy of dehydrogenases and reductases simultaneously induced in the bovine DCs, probably in response to the availability of electron donors and acceptors.ConclusionEHEC EDL933 showed a high flexibility in the activation of genes involved in respiratory pathways and assimilation of carbon and nitrogen sources, most of them from animal origin. This may allow the bacterium to adapt and survive in the various bovine GIT compartments. Obtaining a better understanding of EHEC physiology in bovine GIT is a key step to ultimately propose strategies to limit EHEC carriage and shedding by cattle.