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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Risk Factors for and Treatment of Ketosis in Lactating Dairy Cattle

Gordon, Jessica 07 August 2013 (has links)
This thesis was conducted to investigate risk factors for ketosis development in lactating dairy cattle and evaluate treatments for affected animals. Four main studies were carried out. A systematic review of the ketosis treatment literature was performed to analyze the current body of literature available and provide guidance for treatments to be used in future studies. Secondly, a randomized clinical trial was performed on seventeen commercial dairy farms to determine the effectiveness of a combination butaphosphan cyanocobalamin product, insulin, and propylene glycol for ketosis treatment. A second randomized clinical trial was performed on nine commercial dairy herds to further evaluate the usefulness of a combination butaphosphan cyanocobalamin product and two durations of propylene glycol treatment on ketosis resolution and early lactation milk production. Finally, records from five commercial dairy farms were analyzed to evaluate individual cow risk factors associated with ketosis development. Evaluation of the ketosis treatment literature revealed the lack of well-designed ketosis treatment studies and the need for further investigation to determine an effective treatment regimen. Both treatment trials showed an effect of blood glucose concentrations at the time of enrollment on the efficacy of study treatments that had not been previously described in the literature. Animals that had blood glucose < 2.2 mmol/L at the time of ketosis diagnosis were more likely to cure and produced more milk when treated with insulin, butaphosphan cyanocobalamin, or extended duration of propylene glycol than untreated controls with blood glucose < 2.2 mmol/L. Treatment benefits did not extend to animals with blood glucose > 2.2 mmol/L at the time of enrollment. Older age at first calving, extended days open in the previous lactation, longer dry period, and increased parity increased ketosis risk. Also, animals that were ketotic during a lactation were more likely to become ketotic in the subsequent lactation. The information contained in this thesis helps increase understanding of ketosis risk and proper treatment. The novel interaction of the level of blood glucose and ketosis sheds light on previous inconsistent results on ketosis impacts and will change approaches to understanding and treatment of the condition in the field. / Ontario Ministry of Agriculture and Food, Bayer Animal Health, Vetoquinol, American Association of Bovine Practitioners Research Assistantship
2

Exogenous Ketone Bodies and Endurance Exercise Performance: Is it Worth the Hype?

Brooks, Emma 12 July 2022 (has links)
There has been much consideration over whether exogenous ketone bodies have the capacity to enhance exercise performance through altered substrate metabolism. This systematic review aimed to determine the effects of both ketone precursors and monoesters on endurance exercise performance. A systematic search was conducted in PubMed, SPORTDiscus, and CINAHL for randomized controlled trials investigating endurance performance outcomes in response to ingestion of a ketone supplement compared to a nutritive or non-nutritive control in humans. A meta-analysis was performed to determine the standardized mean difference between interventions using a random-effects model. Hedges’ g and 95% confidence intervals (CI) were reported. The search yielded 569 articles, of which 8 were included in this review (80 participants; 77 men, 3 women). When comparing endurance performance amongst all studies, no significant differences were found between ketone and control trials (Hedges g=0.136; 95% CI, -0.195, 0.467; p=0.419). Sub-analyses based on type of endurance tests showed no significant differences in time to exhaustion (Hedges g=-0.002; 95% CI, -0.312, 0.308; p=0.989) or time trial (Hedges g=0.057; 95% CI, -0.282, 0.395; p=0.744) values. Based on these findings, exogenous ketone precursors and monoesters do not significantly improve endurance exercise performance. While all studies reported an increase in blood ketone concentrations after ingestion, ketone monoesters appear to be more effective at raising concentrations than precursors.
3

Metabolism of exogenous ketones

Stubbs, Brianna January 2016 (has links)
As metabolic substrates, ketone bodies provide an alternative to glucose in order to pro- long survival during starvation. A low carbohydrate, high fat diet can be used to promote ketogenesis without fasting, but long-term compliance can be difficult. Dietary ketone bod- ies may be an alternative method to induce ketosis, so the aim of the work in this Thesis was to investigate the metabolism of exogenous ketones. In the first experimental Chap- ter, the effects of ketone ester and salt drinks on blood &beta;-hydroxybutyrate (βHB), glucose, lipids, electrolytes and pH were determined in healthy humans at rest. Blood D-&beta;HB levels were higher following ketone ester drinks, but it was found that total &beta;HB levels with ke- tone salts were similar, as over 50&percnt; of βHB delivered in the salt was the L-isoform, which was only slowly removed from the blood. Circulating glucose and lipid concentrations fell following both ketone drinks. Blood pH fell following ketone ester consumption, but rose following ketone salt drinks, whilst both compounds raised blood sodium and chloride, and lowered potassium. Work in the second Chapter investigated the repeatability of ketone es- ter metabolism with food, successive drinks or continuous nasogastric (NG) infusion. Peak D-&beta;HB levels were repeatable between- and within- subjects at rest but were lower after a meal, although blood acetoacetate, breath acetone and urine &beta;HB were unaffected by feed- ing. &beta;HB kinetic parameters were not altered by existing hyperketonemia from successive ketone ester drinks and total &beta;HB uptake was identical when isovolumetric amounts of ketone ester were continuously infused through a NG tube. The third Chapter explored side-effects of ketone drinks: ketone ester drinks decreased appetite compared to isocaloric dextrose; which may have been linked to effects of &beta;HB on enteroendocrine cells. Fur- thermore, both ester and salt drinks were found to be unpalatable, and to cause a few, mild gastro-intestinal effects that increased with intake. As exogenous ketones could be a per- formance enhancing supplement in sport, the fourth Chapter used a survey to investigate supplement use by endurance athletes. The results demonstrated widespread supplement use, which was highest at the elite level. In the final Chapter, the effect of glycogen lev- els on the oxidation of &beta;HB was determined in isolated perfused rat hearts. Low cardiac glycogen levels decreased &beta;HB oxidation and levels of the intermediates of glycolysis and the Krebs cycle, whilst increasing muscle amino acid levels, suggesting that low glycogen may have impaired anaplerosis. In conclusion, this work extends current understanding of the novel physiological ketosis that occurs following exogenous ketone consumption.
4

Vybrané parametry látkového metabolismu dojených krav / Selected fabric metabolism parameters of dairy cows

KAŇKA, Vladimír January 2015 (has links)
The aim of this study was to evaluate antiketogenic prophylaxis of the veterinary medicine Kexxtone, in breeding of Holstein cows, in the company Agrodam Hořepník, s.r.o. There were then evaluated the parameters of a metabolic state in the herd monitored. Furthermore I evaluated the milk yield, amount of fats, proteins, lactose and somatic cells in the milk during 100 days of lactation and subsequently, the level of pregnancy after the 1st and the 2nd insemination was evaluated. The observation took place from July 2014 to December 2014 in a way that every two months was selected 8 cows and 8 heifers with a similar calving date. After that they were split into two groups i.e. into the experimental group (the kexxtone medicine was used) and into the control one. These cows were bled and milked. Subsequently, those biological samples were sent to a laboratory to be diagnosed. The higher milk yield was found within the experimental group and so as the content of milk constituents, i.e. fats and proteins. A beneficial effect of this antiketogenic medicine on the amount of ketones in blood and milk of animals was also confirmed within the experimental group. There were not found any significant statistical differences in other monitored parameters.
5

Determining the effect of different levels of vitamin A supply to transition cows on the risk of ketosis and milk production

Rodriguez, Melissa January 2021 (has links)
No description available.
6

The Effect of Nutritional Ketosis on Strength and Power in Tactical Athletes

Barnhart, Emily 24 August 2018 (has links)
No description available.
7

Metabolic Therapy for Age-Dependent Impaired Wound Healing

Kesl, Shannon Lynn 16 March 2016 (has links)
Chronic wounds represent an under-acknowledged socioeconomic epidemic, affecting 1.8 million new patients per year and costing the US health care system upwards of $25 billion annually. This substantial cost is rapidly growing due to a disproportionate occurrence in the ever-aging population. Key features associated with age-related impairment of wound healing include limited energy and nutrient exchange, unremitting inflammations, increased reactive oxygen species (ROS), and diminished blood flow. Most chronic wound therapies target specific molecular mechanisms; however, there are often multiple mitigating factors that prevent normal wound closure. This is likely one reason most wound therapies are minimally effective. In the standard American diet, carbohydrates are broken down for fuel (glucose). While fasting, starvation, and calorie or carbohydrate restriction, beta-oxidation of stored fats in the liver produces ketone bodies (primarily acetoacetate (AcAc) and β-hydroxybutyrate (βHB) to serve as energy metabolites for extra-hepatic tissues. In addition to enhancing metabolic physiology, ketone bodies have recently been discovered to have signaling properties that are independent of their function as energy metabolites. Here we present the evidence for a novel method of inducing therapeutic ketosis via exogenous ketone supplementation to promote enhanced ischemic wound healing in young and aged Fischer 344 rats. Preliminary mechanistic studies demonstrated that exogenous ketone supplementation enhanced wound healing via increasing proliferation and migration, decreasing lactate production, and decreasing ROS production as well as affecting inflammatory cytokines and growth factors. We conclude that exogenous ketone supplementation will be an effective, cost efficient, low toxicity therapy to promote enhancement of wound healing in an aged population.
8

The Effects of Exercise on the Fasting Ketone Production Curve: A Randomized Crossover Study

Deru, Landon S. 28 July 2020 (has links)
Elevated ketone production and utilization results in a host of health benefits. The aim of this study was to assess the rate of ketone production during a prolonged fast and to evaluate how an initial bout of exercise influences this production. Mood and hunger, along with plasma insulin and glucagon, were also assessed. In this crossover study, 20 adult subjects (11 Male, 9 Female) completed two 36-hour fasts, with one protocol requiring the subject to complete an intense treadmill exercise session at the beginning of the fast. Ketone levels were assessed via blood ketone meter and recorded every two hours. Subjective mood and hunger ratings were also recorded every two hours. Venipuncture was performed every 12 hours to assess plasma insulin and glucagon. The mean area under the ketone production curve for the nonexercise intervention was 19.19 ± 2.59 mmol/L and 27.49 ± 2.59 mmol/L for the exercise intervention, resulting in a significant 8.30 mmol/L difference between conditions (95% probability interval was 1.94 to 14.82 mmol/L). The mean time to nutritional ketosis was 21.07 ± 2.95 hours with fasting alone, and 17.5 ± 1.69 hours when combined with exercise (posterior probability = 0.89). There was a significant decrease in insulin over time (F(3,133) = 61.75, p < 0.0001). There was also a significant increase in glucagon over time (F(3,133) = 21.10, p < 0.0001). Hunger and stomach discomfort did not differ between conditions. Anger (F(10,394) = 2.74, p = 0.0028), depression (F(10,394) = 2.91, p = 0.0016), tension (F(10,394) = 2.29, p = 0.0128), vigor (F(10,394) = 11.65, p < 0.0001), and fatigue (F(10,394) = 10.60, p = 0.0001) increased over the course of the fast, but did not differ between conditions. Completing aerobic exercise at the beginning of a 36-hour fast results in significantly more ketone production. The impact of exercise on ketone production comes at little or no impact on hunger, stomach discomfort and negative moods. A difference in time to achieving nutritional ketosis between conditions may exist, but this was not observed in this study.
9

Infection par le virus de l'herpès humain de type 8 (HHV8) et inflammation : implications dans le diabète de type 2 cétonurique. / Human herpes virus type 8 infection : implications in Ketosis prone type 2 diabetes

Lontchi Yimagou, Eric 30 September 2015 (has links)
Le Ketosis-Prone Diabetes (KPD) est un phénotype de diabète intermédiaire entre le diabète de type 1 et le diabète de type 2, fréquemment rencontré chez le sujet d’origine noire africaine. Cette forme de diabète suscite un intérêt certain de par son évolution clinique marquée notamment par la restauration de l’insulinosécrétion initialement altérée. Sobngwi et coll. en 2008 ont établi une association entre le virus HHV8 et le KPD chez des sujets Africains vivant en France. Nulle part ailleurs l’étude n’a été reproduite. L’objectif de cette thèse était de rechercher la potentielle association entre l’infection à HHV8 et le KPD ; puis d’évaluer l’impact de l’infection à HHV8 sur le profil inflammatoire des phénotypes du diabète de type 2. L’étude s’appuie sur une population de patients Africains vivant en Afrique admis consécutivement pour une décompensation hyperglycémique (glycémie à jeun≥2,5g/l) au Centre National d’Obésité de l’Hôpital Central de Yaoundé. Plus spécifiquement, il était question de :• étudier la fréquence du diabète non auto-immun à tendance cétosique (KPD); • étudier l’association entre le virus HHV8 et le KPD;• rechercher si l’infection à HHV8 est associée à un profil inflammatoire pouvant participer aux phénotypes de diabète. Etait inclus dans l’étude tout patient diabétique âgé de plus de 18 ans présentant un diabète aigu avec syndrome cardinal et cétonurie (KPD1), ceux ayant présenté un diabète inaugural aigu avec syndrome cardinal et cétonurie et en rémission depuis plus de trois mois et sans cétonurie à l’inclusion (KPD2), et ceux présentant un diabète de type 2 connu sans cétonurie (DT2). Etait exclu de l’étude tout patient présentant des stigmates d’auto-immunité du diabète de type 1 A, un diabète « MODY », une endocrinopathie, une maladie du pancréas, ou un diabète de type auto-immun. Chez l’ensemble des participants admis, nous avons collecté les données cliniques (le poids, la taille, l’IMC, le rapport tour de taille sur tour de hanche, la pression artérielle, et le pourcentage de graisse) et des prélèvements à jeun ont été effectués (sérum et cellules mononuclées du sang périphérique) pour les analyses biologiques : la glycémie par glucose oxydase, l’HbA1c par HPLC, les paramètres du profil lipidique par des methodes enzymatiques, les concentrations d’insuline et de peptide-C par électrochimiluminescence, les anticorps anti-HHV8 par immunofluorescence, l’ADN viral HHV8 par PCR en temps réel, et les marqueurs de l’inflammation par le Luminex. Les indices HOMA-β et HOMA-IR ont été utilisés pour évaluer l’insulinosécrétion et la sensibilité à l’insuline respectivement. Les marqueurs sérologiques de l’inflammation recherchés étaient : TNF-α, MCP-1, IL-8, MIP-1β, VEGF et MIP-1α... / Ketosis-Prone Diabetes (KPD) is a diabetes phenotype intermediate between type 1 and type 2 diabetes, frequently encountered in populations of African origin. This form of diabetes arouses some interest because of its clinical course marked in particular by restoring the initial impaired insulin secretion. Sobngwi et al. in 2008 established an association between HHV-8 virus and KPD in African population living in France. Nowhere else has the study been replicated. The objective of this thesis was to investigate the potential association between HHV-8 infection and KPD; then evaluate the impact of HHV-8 infection on the inflammatory profile of type 2 diabetes phenotypes. The study is based on African patients living in Africa consecutively admitted for hyperglycemic decompensation (Fasting blood glucose≥2,5g/l) at the National Obesity Centre of the Yaounde Central Hospital. More specifically, the issue was:• study the frequency of non-immune ketosis-prone diabetes (KPD);• investigate the association between HHV8 and KPD;• investigate whether HHV-8 infection is associated with an inflammatory profile that may participate in diabetes phenotypes.Was included in this study all diabetic patients old more than 18 years with acute diabetes with syndrome cardinal and ketonuria (KPD1), those who presented with an acute inaugural cardinal syndrome and diabetes ketonuria and in remission for more than three months and without ketonuria at baseline (KPD2), and those with type 2 diabetes experienced without ketonuria (T2D). Was excluded from the study all patient with stigmata of autoimmunity of type 1 A diabetes, diabetes "MODY", endocrinopathy, pancreatic disease or an autoimmune diabetes.Among all participants admitted, we collected clinical data (weight, height, BMI, waist to hip ratio, blood pressure, and the percentage of fat) and levies fasting were made (serum and peripheral blood mononuclear cells) for biological testing: glyceamia by glucose oxidase, HbA1c by HPLC, lipid profile by enzymatic methods, the insulin and C-peptide concentrations by electrochemiluminescence, anti-HHV8 antibodies by immunofluorescence, HHV8 viral DNA by real-time PCR, and markers of inflammation by Luminex. HOMA-β and HOMA-IR indices were used to assess insulinsecretion and insulinsensitivity respectively. Serological markers of inflammation investigated were : TNF-α, MCP-1, IL-8, MIP-1β, MIP-1α and VEGF...
10

Untersuchung von Stoffwechselparametern und Lipoproteinen im Blutserum von einlings- und zwillingsträchtigen Merino- und Schwarzköpfigen Fleischschafen im peripartalen Zeitraum

Flocke, Alexandra 13 June 2013 (has links) (PDF)
Alexandra Flocke Untersuchung von Stoffwechselparametern und Lipoproteinen im Blutserum von einlings- und zwillingsträchtigen Merino- und Schwarzköpfigen Fleischschafen im peripartalen Zeitraum Medizinische Tierklinik, Veterinärmedizinische Fakultät, Universität Leipzig Eingereicht im Februar 2012 (94 Seiten, 15 Abbildungen, 8 Tabellen, 199 Literaturangaben, 12 Tabellen im Anhang) Schlüsselwörter: Lipoproteine, Schaf, Stoffwechsel, Endotoxin, Ketose Problemstellung: Der Lipoproteinstatus in der kritischen Phase der Hochträchtigkeit wurde beim Schaf bisher nur wenig untersucht. Die Fähigkeit der Lipoproteine, sowohl Lipide zu transportieren und im Körper umzuverteilen, als auch ihre Rolle in der Endotoxinneutralisation machen sie zu einem wichtigen Parameter in stoffwechselbelasteten Situationen. Das Ziel dieser Arbeit ist es, den Lipoproteinstatus zweier verschiedener Leistungsrassen zu analysieren und zu prüfen, ob und inwiefern peripartal Unterschiede bei Ein- und Zwillingsträchtigkeiten bestehen. Zusätzlich werden die Endotoxine der Tiere bestimmt und mögliche Zusammenhänge mit der Stoffwechselsituation und dem Lipoproteinstatus evaluiert. Tiere, Material und Methoden: Untersucht wurden gesunde einlingsträchtige Merinofleischschafe (MFS1), zwillingsträchtige Merinofleischschafe (MFS2) sowie zwillingsträchtige Schwarzköpfige Fleischschafe (SKF2). Im Abstand von je sieben Tagen wurden den Tieren im Zeitraum von der 5. Woche a.p. bis eine Woche p.p. Blutproben aus der V. jugularis externa entnommen. Aus dem Serum wurden die Konzentrationen von β-Hydroxybutyrat (BHB), Glucose, Freie Fettsäuren (FFS), Triacylglycerol (TG), Cholesterol, Bilirubin, Gesamtprotein (alle Hitachi 912), Insulin (RIA-Kit, Firma IBL, Hamburg), α- und β-Lipoproteine (LIPIDOPHOR All In12®, - ohne prä-β-Lipoproteine), freies Endotoxin (LAL-Test) und Anti-Lipid A Antikörper (ALAAK; ELISA) bestimmt. Ergebnisse: Die α-Lipoproteinkonzentration stieg bei den MFS1 vor dem Ablammen signifikant an und erreichte eine Konzentration von = 208,0 ± 40,1 mg/dl (1. Woche a.p.). Die MFS2 wiesen vor dem Lammen einen konstanten Verlauf zwischen = 180,4 ± 31,1 mg/dl (5. Woche a.p.) und = 196,1 ± 42,1 mg/dl (3. Woche a.p.) auf. Die SKF2 zeigten in der 5. Woche a.p. mit = 206,5 ± 39,0 mg/dl eine größtenteils signifikant höhere Konzentration gegenüber den folgenden Untersuchungszeitpunkten. Bei beiden Rassen ließ sich bei den Zwillingsmuttern nach dem Lammen ein signifikanter Abfall der α-Lipoproteinkonzentration auf = 144,3 ± 46,1 mg/dl (MFS2) bzw. = 170,2 ± 48,8 mg/dl (SKF2) feststellen. Es bestand eine gesicherte Korrelation zu Cholesterol. Die β-Lipoproteinkonzentration lag in der 1. Woche p.p. bei den Zwillingsmuttern (MFS2 und SKF2) signifikant niedriger als vor dem Lammen. Die SKF2 wiesen in der 5. und 4. Woche a.p. signifikant niedrigere Konzentrationen als die MFS1 auf. Gesicherte Korrelationen bestanden zu TG, Cholesterol und ALAAK (MFS1). Für die α-Lipoproteinkonzentration wurde ein Referenzbereich von 144,3 – 208,0 mg/dl und für die β-Lipoproteinkonzentration von 13,6 – 28,0 mg/dl bei Muttertieren der beschriebenen Rassen ermittelt. Ausgenommen die Insulinkonzentration in der 1. Woche a.p. bestanden keine signifikanten Differenzen zwischen MFS1 und MFS2. Im Vergleich der Rassen zeigten sich signifikante Differenzen in der Glucosekonzentration in der 2. Woche a.p. und in der Konzentration von Bilirubin in der 3. und 1. Woche a.p.. Die BHB-Konzentration zeigte einen konstanten Verlauf und stieg bei den MFS1 bis auf = 0,96 ± 0,36 mmol/l eine Woche p.p., bei den MFS2 auf = 0,73 ± 0,35 mmol/l und bei den SKF2 auf = 0,63 ± 0,14 mmol/l eine Woche a.p. signifikant an. Gesicherte Korrelationen bestanden zu FFS (MFS2) und Insulin (MFS2; SKF2). Die Glucosekonzentration zeigte sich bei den Zwillingsmuttern nach zunächst abfallenden Konzentrationen in der Hochträchtigkeit eine Woche p.p. signifikant höher ( = 3,63 ± 0,59 mmol/l; MFS2 und = 3,28 ± 0,42 mmol/l; SKF2) als vor dem Lammen. Gesicherte Korrelationen ließen sich zu FFS (MFS1; MFS2), BHB (MFS2) und dem Zeitpunkt der Untersuchung (MFS2; SKF2) feststellen. Die FFS-Konzentration stieg bei den SKF2 zur 1. Woche a.p. auf = 265 ± 131 μmol/l an, fiel eine Woche p.p. signifikant auf = 128 ± 95 μmol/l ab und korrelierte gesichert mit TG. Die TG-Konzentration fiel von der 1. Woche a.p. bis zur 1. Woche p.p. signifikant auf = 0,19 mmol/l (MFS1; SKF2) bzw. = 0,18 ± 0,05 mmol/l (MFS2) ab und korrelierte mit Gesamtprotein (MFS1), Cholesterol (MFS1; MFS2), β-Lipoproteinen (MFS1; MFS2) und freiem Endotoxin (MFS1). Die Cholesterolkonzentration fiel eine Woche p.p. bei den Zwillingsmuttern signifikant ab, bei den MFS1 war der Verlauf konstant. Die Bilirubinkonzentration stieg eine Woche p.p. signifikant an (MFS1; MFS2) und korrelierte mit der Konzentration von freiem Endotoxin. Das Gesamtprotein sank zum Zeitpunkt des Ablammens hin signifikant ab, erreichte jedoch eine Woche p.p. wieder seine Ausgangskonzentration. Eine gesicherte Korrelation konnte mit ALAAK festgestellt werden (MFS2; SKF2). Freies Endotoxin konnte zu jedem Zeitpunkt der Untersuchungsreihe nachgewiesen werden. Dabei lagen die festgestellten Konzentrationen bei x̃ = 0,06 – 1,30 EU/ml. Eine gesicherte Korrelation fand sich mit der Konzentration der ALAAK (MFS2). ALAAK konnten ebenfalls zu jedem Zeitpunkt in Konzentrationen von x̃ = 22,2 - 56,8 (OD-Wert) nachgewiesen werden. Fazit: Die Lipoproteinkonzentrationen in den einzelnen Gruppen zeigten sich a.p. zunächst regulativ den erhöhten peripartalen Belastungen des Lipidstoffwechsels angepasst, p.p. demonstrierte auch die Abnahme der Lipoproteinkonzentrationen das Ende der lipolytischen Aktivität bei den Schafen. Die vorliegenden Ergebnisse der Stoffwechselparameter lassen auf eine stärkere Belastung der Zwillingsmuttern schließen, welche auch die Lipoproteine mit einbezieht. Freies Endotoxin konnte auch bei gesunden Schafen zwar zu jedem Zeitpunkt nachgewiesen, eine gesicherte Korrelation mit der Lipoproteinkonzentration jedoch nicht festgestellt werden. / Alexandra Flocke Evaluation of metabolic parameters and lipoproteins in the serum of merino and blackhead sheep for meat production with one or two lambs in the peripartal period Large Animal Clinic for Internal Medicine, Faculty of Veterinary Medicine, University of Leipzig Submitted in February 2012 (94 pages, 15 figures, 8 tables, 199 references, 12 tablets in the appendix) Keywords: lipoproteins, sheep, metabolism, endotoxin, ketosis Objective: The lipoprotein status in the critical phase of the peripartal period of sheep has been few reviewed. The ability of lipoproteins to transport and redistribute lipids in the organism and their capacity for endotoxinneutralisation makes them a considerable parameter in metabolic bonded situations. The objective of this research is to show the lipoprotein status of two competitive breeds and to proof if and to what extend differences between ewes with one and two lambs exist. Additionally, the endotoxic situation is assigned and possible correlations with the metabolic system and the lipoprotein status are evaluated. Animals, materials and methods: The research contains healthy merino sheep with one lamb (MFS1), merino sheep with two lambs (MFS2) and blackhead sheep with two lambs (SKF2). At intervals of seven days, blood samples out of the V. jugularis externa were taken from the animals in a period from the 5th week a.p. to one week p.p.. Concentrations in the serum of the following parameters were defined: β-hydroxybutyrat (BHB), glucose, free fatty acids (FFS), triacylglycerol (TG), cholesterol, bilirubin, total protein (all Hitachi 912), insulin (RIA-kit, IBL, Hamburg), α- and β-lipoprotein (LIPIDOPHOR All In12® - without pre-β-lipoprotein), free endotoxin (LAL-test) and anti-lipid A antibodies (ALAAK). Results: The concentration of α-lipoproteins of the MFS1 increased significantly before parturition and finally reached 208,0 ± 40,1 mg/dl (1st Week a.p.). The group of MFS2 showed a constant deviation between = 180,4 ± 31,1 mg/dl (5th Week a.p.) and = 196,1 ± 42,1 mg/dl (3rd week a.p.) before parturition. The SKF2 evidenced with a concentration of = 206,5 ± 39,0 mg/dl in the 5th week a.p. a predominantly significant higher result as during following points in time. Both groups carrying twins showed a significant decrease of the α-lipoprotein concentration down to = 144,3 ± 46,1 mg/dl (MFS2) or = 170,2 ± 48,8 mg/dl (SKF2) after parturition. There were statistically reliable correlations between the α-lipoprotein concentration and cholesterol. The β-lipoprotein concentration from both twin pregnant groups had been significantly lower one week after parturition than before parturition. The results of the SKF2 in week 5 and 4 a.p. were significantly lower than those of the MFS1. Reliable correlations could be determined with TG, cholesterol and ALAAK (MFS1). An α-lipoprotein reference range for ewes of the introduced breeds could be determined from 144,3 - 208,0 mg/dl and for β-lipoproteins from 13,6 - 28,0 mg/dl. There were no significant differences between MFS1 and MFS2 except the concentration of insulin in the 1st week a.p.. In the comparison of the different breeds, significant differences in the concentration of glucose (2nd week a.p.) and bilirubin (3rd week a.p. and 1st week a.p.) could be shown. The concentration of BHB showed a constant deviation and increased significantly to = 0,96 ± 0,36 mmol/l (MFS1; 1st week p.p.), = 0,73 ± 0,35 mmol/l (MFS2, 1st week a.p.) or = 0,63 ± 0,14 mmol/l (SKF2, 1st week a.p.), respectively. Reliable correlations existed with FFS (MFS2) and insulin (MFS2; SKF2). The concentration of glucose of the twin pregnant ewes decreased initially before parturition and increased significantly again in the 1st week p.p. ( = 3,63 ± 0,59 mmol/l; MFS2 and = 3,28 ± 0,42 mmol/l; SKF2). Reliable correlations had been determined with FFS (MFS1; MFS2), BHB (MFS2) and the time of sampling (MFS2; SKF2). Concentrations of FFS increased in the group of SKF2 to = 265 ± 131 μmol/l in the 1st week a.p., decreased again significantly to = 128 ± 95 μmol/l one week p.p. and showed a correlation with TG. The TG concentration decreased significantly from one week a.p. to one week p.p. down to = 0,19 mmol/l (MFS1; SKF2) and = 0,18 ± 0,05 mmol/l (MFS2), respectively. A reliable correlation existed between TG and total protein (MFS1), cholesterol (MFS1; MFS2), β-lipoproteins (MFS1; MFS2) and free endotoxin (MFS1). Both twin pregnant groups had a significant decrease in the cholesterol concentration one week after parturition, in contrast the group of MFS1 showed a constant deviation. The concentration of bilirubin increased significantly one week p.p. (MFS1; MFS2) and showed a reliable correlation with the concentration of free endotoxin. Total protein decreased significantly towards parturition, but reached its initial concentration again one week p.p.. A statistically reliable correlation could be determined with ALAAK (MFS2; SKF2). Free endotoxin could be detected at any point of the exploration. The observed concentrations ranged from x̃ = 0,06 – 1,30 EU/ml. A reliable correlation could be shown with the concentration of ALAAK (MFS2). ALAAK was detected as well in concentrations from x̃ = 22,2 - 56,8 (OD-value) in any taken sample. Conclusion: The lipoprotein concentrations in each group appeared a.p. initially adapted to the peripartal bonds of the increased lipid metabolism. After parturition, the decrease in lipoprotein concentrations, too, demonstrated the end of the lipolytic activity of the ewes. The results of the metabolic parameters lead to the conclusion of a stronger liability of the ewes with twins. This is also valid for the lipoproteins. Free endotoxin could be detected in healthy sheep at any time, but a reliable correlation with the concentration of lipoproteins was not visible.

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