Theses and Dissertations at Montana State University (MSU)

Permanent URI for this collectionhttps://scholarworks.montana.edu/handle/1/733

Browse

Search Results

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    The influences of diet and water systems on rainbow trout gut microbiome in relation to nutrient utilization
    (Montana State University - Bozeman, College of Agriculture, 2017) Betiku, Omolola Comfort; Chairperson, Graduate Committee: Carl Yeoman; T. Gibson Gaylord and Wendy M. Sealey were co-authors of the article, 'Evaluation of protein reduction and essential amino acids supplementation of plant- and animal protein-based diets on production of rainbow trout (Oncorhynchus mykiss)' submitted to the journal 'Journal of the World Aquaculture Society' which is contained within this thesis.; Carl J. Yeoman, T. Gibson Gaylord, Suzanne L. Ishaq, Glenn C. Duff, Aurelien Mazurie and Wendy M. Sealey were co-authors of the article, 'Divided nutritive function of the rainbow trout (Oncorhynchus mykiss) mid- and hind- gut microbiomes' submitted to the journal 'Frontiers in microbiology' which is contained within this thesis.; Carl J. Yeoman, T. Gibson Gaylord, Glenn C. Duff, Brian Bothner, Stephanie S. Block and Wendy M. Sealey were co-authors of the article, 'Differences in amino acid catabolism by gut microbes with/without prebiotics inclusion in GDDY-based diet affect feed utilization in rainbow trout' submitted to the journal 'Aquaculture' which is contained within this thesis.; Carl J. Yeoman, T. Gibson Gaylord, Ben Americus, Sarah Olivo, Glenn C. Duff and Wendy M. Sealey were co-authors of the article, 'Water system is a controlling variable modulating bacterial diversity of gastrointestinal tract and performance in rainbow trout' submitted to the journal 'Plos one' which is contained within this thesis.
    Plant protein ingredients are sustainable sources of protein that could be used to meet the demand of the growing aquaculture industry. However, feeding plant protein diets has some drawbacks in terms of reduced growth and poor feed efficiency. This dissertation evaluated the production cost of alternative protein diets for commercial production of rainbow trout. Also, it identified the microbiota and gene functions associated with alternative diets and how they differ between mid- and hind-gut sections of the rainbow trout intestine. Furthermore, it determined differences in microbial community compositions and functions in the luminal and mucosal GIT of trout when fed alternative diets, with/without prebiotics. Lastly, the significance of diet and water as environmental factors shaping the mucosal and luminal bacterial compositions in trout was investigated. Experiment 1 demonstrated that trout growth and body indices were not affected by feeding plant protein diet (PPD). In experiment 2, shotgun metagenomics revealed predominant bacterial population in trout microbiota. Genes related to carbohydrate metabolism were increased in the hindgut intestine of those fed PPD. Experiment 3 demonstrated that replacing fishmeal with 75% GDDY did not alter growth of trout, but not feed intake and feed conversion ratio (FCR). High inclusion of GDDY in trout diet resulted in enrichment of catabolic genes involving branched chain amino acids in trout midgut region. Experiment 4 showed that rearing in a recirculating water system significantly improved trout performance compared to rearing in a flow-through water system, while feed intake and FCR increased in fish raised in the flow-through system. Water samples were more diverse than GIT samples. Bacterial diversity was greater in mucosal scrapings of the GIT than in the lumen. Water system played a major role influencing the microbial communities in trout luminal and mucosal GIT. The lumen shared similar bacteria with the rearing water. The results of this study demonstrated that plant protein can effectively substitute for fishmeal in trout diets. It further showed that trout GIT microbiota vary between the mid- and hind-GIT. The hind-, but not the mid-GIT microbiome appears to be modulated by diet, while the mid-GIT is affected by water system.
  • Thumbnail Image
    Item
    Characterizating low-quality forage utilization : feed value of a solid stem straw & effects of an abrupt switch from corn-containing to forage-only diets
    (Montana State University - Bozeman, College of Agriculture, 2010) Voigt, Lindsey Ann; Chairperson, Graduate Committee: Rachel L. Endecott.
    Two separate studies were conducted to characterize low-quality forage utilization. The objective of the first trial was to evaluate the suitability of common small grain straws as efficient roughage sources in livestock diets, specifically comparing a solid-stem winter wheat variety (Bynum) to hollow-stemmed varieties of winter wheat (Norris and Willow Creek) and a barley variety (Geraldine). This was a two-part trial involving an in vitro dry matter disappearance (IVDMD) experiment and an individual lamb feeding trial. The IVDMD kinetics trial was conducted using a Daisy Wheel TM incubator, with replicated straw samples removed after 0, 6, 12, 24 48 and 96 hours. In a feeding trial, 16 crossbred wether lambs were randomly assigned to one of four diets containing chopped straw. The solid-stem characteristic of Bynum did not affect the feeding value of the straw compared with barley straw and other winter wheat varieties. The objective of the second trial was to characterize how quickly the rumen adapts to a forage-only diet after an abrupt switch from a concentrate-containing diet. Twelve ruminally-cannulated Hereford-cross heifers were randomly assigned to 3 individually-fed, pre-experiment diets (4 heifers/diet). Diets were: 1) all forage, 2) 35% concentrate, and 3) 70% concentrate. Heifers were fed the diets for ~100 d before the start of the trial. Pre-experiment diets consisted of grass-alfalfa hay, corn, and soybean meal-urea supplement added to make the diets isonitrogenous at 13% CP. On d 0, diets were abruptly switched to grass hay. In situ digestibility runs were conducted starting on d -8 and ran continuously (d 1, 4, 7, 10, 13, 16, 19, 22) after the diet switch. Duplicate sample bags filled with 5 g of grass hay and a blank bag were incubated for 0, 24, 48, and 96 h. Organic matter and NDF digestibilities in subsequent in situ runs were similar (P > 0.10), regardless of pre-experiment diet. Rate of digestion was not influenced by pre-experiment diet (P = 0.74; avg 4.3 ± 0.002%/h). Forage digestibility was depressed when heifers were fed a high-concentrate diet; however, this effect disappeared within 48 h of feeding 100% forage.
  • Thumbnail Image
    Item
    Effects of increasing tetany risk ratio and magnesium supplementation on mineral balance and feeding behavior by ruminants
    (Montana State University - Bozeman, College of Agriculture, 2011) Norvell, Tess Marie; Chairperson, Graduate Committee: John Paterson.
    Three experiments were conducted to evaluate the effects of increasing the tetany risk ratio on blood serum Mg levels, nutrient digestion, mineral balance, and Mg supplementation source and feeding behavior. Experiments 1 and 2 were randomized complete block designs, with 24 wethers were maintained in individual metabolism crates and assigned to four treatments (6 wethers/treatment). Experiment 1 compared tetany risk ratios (TRR) of 1.6, 2.3, 2.9, or 3.5. Dry matter, NDF, and N digestibilities were not different between treatments. Nitrogen retention decreased (P < 0.05) as the tetany risk ratio increased. No treatment differences were recorded in Mg, Ca, K, or P balance. The TRR 2.3 treatment had the greatest decrease (P < 0.05) in serum Mg after 15d. Experiment 2 compared tetany risk ratios of 1.5, 2.6, 1.5 plus MgO, or 1.5 plus MgCl. The TRR 2.6 treatment showed increased (P < 0.05) DM, NDF, and N digestibilities when compared to all other treatments. Nitrogen digestibility decreased (P < 0.05) with the addition of supplemental Mg. No treatment differences in Mg, Ca, K, or P balance were recorded. The TRR 2.6 treatment had the greatest decrease (P < 0.05) in serum Mg after 5 d. Experiment 3 was a cafeteria study using a switchback design, 23 Angus heifers were weighed and randomly assigned to one of two locations (11 heifers in drylot, and 12 heifers on pasture) containing two mineral supplements (0.0% Mg and 10.0% Mg). The groups were rotated between locations after 15 d for 30 d of measurements. Individual mineral consumption (grams/d), feeder attendance (trips/d), and feeding duration (seconds/d) were measured using a GrowSafe® individual feeding system. Heifers consumed 119% more (P < 0.01) 0.0% Mg supplement each day than the 10.0% Mg. Heifers made almost twice as many (P < 0.01) trips to the feeder, and spent an additional 91.3 s consuming the 0.0% Mg than the 10.0% Mg. Total mineral intakes were 87.3 % greater (P < 0.01) when supplemented on pasture compared to drylot. During the first 15 d, total mineral intakes were higher (P < 0.01) than for the second 15 d.
Copyright (c) 2002-2022, LYRASIS. All rights reserved.