Browsing by Author "Gedye KR"

Now showing 1 - 4 of 4
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    A new monocomponent xylanase improves performance, ileal digestibility of energy and nutrients, intestinal morphology, and intestinal microbiota in young broilers
    (Elsevier Inc. on behalf of Poultry Science Association Inc., 2023-03-01) Vasanthakumari BL; Gedye KR; Abdollahi MR; Di Benedetto M; Sanchez DG; Wealleans A; Ravindran V
    Supplementation of feed enzymes such as xylanases has been shown to lower intestinal digesta viscosity and improve nutrient digestion thereby resulting in better gut health due to the reduced availability of undigested nutrients for the growth of harmful bacteria. Oligosaccharides produced by xylanase in situ from dietary non-starch polysaccharides with potential prebiotic effects could modulate the gut microbiome. This paper reports the positive effects of a new monocomponent xylanase in improving performance and nutrient digestion and modulating the intestinal microbiota of broilers. A corn-wheat-soybean meal-based diet was formulated and used to develop 3 dietary treatments using different doses (0, 45,000 U/kg and 90,000 U/kg) of the xylanase. A total of 288, one-day-old male broiler (Ross 308) chicks were allocated to 36 cages (12 replicates per treatment and 8 chicks per cage) and offered the experimental diets from d 0 to 21 post-hatch. The data were subjected to ANOVA using the General Linear Models procedure of SAS. The results confirm that supplemental xylanase at both dose levels improved (P < 0.05) broiler performance and nutrient digestibility. Xylanase supplementation had significant (P < 0.05) effects in modulating the intestinal microbiota with a higher relative abundance of commensal bacteria such as Lactobacillus and a lower abundance of potentially non-beneficial bacteria such as E. shigella indicating a prebiotic mode of action.
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    Genome-Wide Association Studies of Live Weight at First Breeding at Eight Months of Age and Pregnancy Status of Ewe Lambs
    (MDPI (Basel, Switzerland), 2023-03-27) Haslin E; Pettigrew EJ; Hickson RE; Kenyon PR; Gedye KR; Lopez-Villalobos N; Jayawardana JMDR; Morris ST; Blair HT; Ahmad SM
    This study estimated genetic parameters and identified candidate genes associated with live weight, and the occurrence of pregnancy in 1327 Romney ewe lambs using genome-wide association studies. Phenotypic traits considered were the occurrence of pregnancy in ewe lambs and live weight at eight months of age. Genetic parameters were estimated, and genomic variation was assessed using 13,500 single-nucleotide polymorphic markers (SNPs). Ewe lamb live weight had medium genomic heritability and was positively genetically correlated with occurrence of pregnancy. This suggests that selection for heavier ewe lambs is possible and would likely improve the occurrence of pregnancy in ewe lambs. No SNPs were associated with the occurrence of pregnancy; however, three candidate genes were associated with ewe lamb live weight. Tenascin C (TNC), TNF superfamily member 8 (TNFSF8) and Collagen type XXVIII alpha 1 chain (COL28A1) are involved in extracellular matrix organization and regulation of cell fate in the immune system. TNC may be involved in ewe lamb growth, and therefore, could be of interest for selection of ewe lamb replacements. The association between ewe lamb live weight and TNFSF8 and COL28A1 is unclear. Further research is needed using a larger population to determine whether the genes identified can be used for genomic selection of replacement ewe lambs.
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    One dog's waste is another dog's wealth: A pilot study of fecal microbiota transplantation in dogs with acute hemorrhagic diarrhea syndrome
    (PLOS, 2021-04-19) Gal A; Barko PC; Biggs PJ; Gedye KR; Midwinter AC; Williams DA; Burchell RK; Pazzi P; Carbonero F
    Canine acute hemorrhagic diarrhea syndrome (AHDS) has been associated in some studies with Clostridioides perfringens overgrowth and toxin-mediated necrosis of the intestinal mucosa. We aimed to determine the effect of a single fecal microbiota transplantation (FMT) on clinical scores and fecal microbiomes of 1 and 7 dogs with AHDS from New Zealand and South Africa. We hypothesized that FMT would improve AHDS clinical scores and increase microbiota alpha-diversity and short-chain fatty acid (SCFA)-producing microbial communities' abundances in dogs with AHDS after FMT. We sequenced the V3-V4 region of the 16S-rRNA gene in the feces of AHDS FMT-recipients and sham-treated control dogs, and their healthy donors at admission, discharge, and 30 days post-discharge. There were no significant differences in median AHDS clinical scores between FMT-recipients and sham-treated controls at admission or discharge (P = 0.22, P = 0.41). At admission, the Shannon diversity index (SDI) was lower in AHDS dogs than healthy donors (P = 0.002). The SDI did not change from admission to 30 days in sham-treated dogs yet increased in FMT-recipients from admission to discharge (P = 0.04) to levels not different than donors (P = 0.33) but significantly higher than sham-treated controls (P = 0.002). At 30 days, the SDI did not differ between FMT recipients, sham-treated controls, and donors (P = 0.88). Principal coordinate analysis of the Bray-Curtis index separated post-FMT and donor dogs from pre-FMT and sham-treated dogs (P = 0.009) because of increased SCFA-producing genera's abundances after FMT. A single co-abundance subnetwork contained many of the same OTUs found to be differentially abundant in FMT-recipients, and the abundance of this module was increased in FMT-recipients at discharge and 30 days, compared to sham-treated controls. We conclude in this small pilot study FMT did not have any clinical benefit. A single FMT procedure has the potential to increase bacterial communities of SCFA-producing genera important for intestinal health up to 30 days post-FMT.
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    X-linked myotubular myopathy associated with an MTM1 variant in a Maine coon cat
    (Wiley Periodicals LLC on behalf of American College of Veterinary Internal Medicine, 2022-09-26) Kopke MA; Shelton GD; Lyons LA; Wall MJ; Pemberton S; Gedye KR; Owen R; Guo LT; Buckley RM; Valencia JA; 99 Lives Consortium; Jones BR
    OBJECTIVE: Describe the clinical course and diagnostic and genetic findings in a cat with X-linked myotubular myopathy. CASE SUMMARY: A 7-month-old male Maine coon was evaluated for progressively worsening gait abnormalities and generalized weakness. Neurolocalization was to the neuromuscular system. Genetic testing for spinal muscular atrophy (LIX1) was negative. Given the progressive nature and suspected poor long-term prognosis, the owners elected euthanasia. Histopathology of skeletal muscle obtained post-mortem disclosed numerous rounded atrophic or hypotrophic fibers with internal nuclei or central basophilic staining. Using oxidative reactions mediated by cytochrome C oxidase and succinic dehydrogenase, scattered myofibers were observed to have central dark staining structures and a "ring-like" appearance. Given the cat's age and clinical history, a congenital myopathy was considered most likely, with the central nuclei and "ring-like" changes consistent with either centronuclear or myotubular myopathy. Whole genome sequencing identified an underlying missense variant in myotubularin 1 (MTM1), a known candidate gene for X-linked myotubular myopathy. NEW OR UNIQUE INFORMATION PROVIDED: This case is the first report of X-linked myotubular myopathy in a cat with an MTM1 missense mutation. Maine coon cat breeders may consider screening for this variant to prevent production of affected cats and to eradicate the variant from the breeding population.