University of Veterinary Science

About: University of Veterinary Science is a education organization based out in Pyinmana, Myanmar. It is known for research contribution in the topics: Population & Feed conversion ratio. The organization has 597 authors who have published 650 publications receiving 14262 citations.

EpidemiologicaL studies on atrophic rhinitis in swine. IX. Investigations on the introduction of the disease.

Abstract: Summary The fundamental causes of a mass incidence of atrophic rhinitis were investigated in five large pig production units (F, G, H, I, J) by monitoring the epizootiological situation. Epizootiological monitoring included comparative analysis of Bordetella bronchiseptica and Pasteurella multocida strains isolated before and during the mass incidence for their antigenic and other biological properties, and a follow-up of stock imports, conditions of management, and clinical and post mortem signs of atrophic rhinitis. Antigen analysis disclosed that new pathogens, introduced by imported stock, are usually responsible for outbreaks if the strains isolated during them show a change in capsular antigen composition, and as a rule also a greater virulence and exotoxin production than the strains indigenous in the herd (units F and G). In contrast, management-related factors can be incriminated if the strains isolated during mass incidence do not differ antigenically from previous isolates, but show a considerable increase in virulence (units H, I and J). The marketing of breeding animals should therefore be prohibited and control should be tightened upon the management measures in herds intended for the production of breeding stock, since clinically healthy pigs originating from such herds may also be carriers of virulent pathogens. Zusammenfassung Epidemiologische Untersuchungen der Rhinitis atrophicans bei Schweinen IX. Untersuchungen uber die Verbreitung und Ausbruch der Krankheit In funf grosen Mastschweinbestanden (F, G, H, I, J) wurden die Ursachen eines Massenausbruchs der Rhinitis atrophicans durch Uberwachung der epizootologischen Gegebenheiten erforscht. Die epizootologische Uberwachung bestand einmal aus vergleichenden Untersuchungen von Bordetella bronchiseptica- und Pasteurella multocida-Stammen, die vor und wahrend eines Massenausbruchs isoliert und auf antigenische und andere biologische Eigenschaften untersucht wurden. Weiter wurden angekaufte Tiere und der Zustand des Managements kontrolliert und klinische Symptome und postmortale Befunde registriert. Die Analyse der Antigenstruktur ergab, das neue pathogene Stamme, eingeschleppt durch angekaufte Tiere, gewohnlich verantwortlich waren fur die Ausbruche, wenn die Stamme, die dabei isoliert wurden, eine Veranderung in der kapsularen antigenen Zusammensetzung zeigten. In der Regel wiesen diese Stamme eine hohere Virulenz und Exotoxinproduktion auf als die einheimischen Stamme in den Herden (Bestande F und G). Dagegen konnen Faktoren, die das Management betreffen, verantwortlich gemacht werden, wenn die wahrend eines Massenausbruchs isolierten Stamme sich in der Antigenstruktur nicht von den vorhergegangenen Isolaten unterscheiden, jedoch eine betrachtliche Zunahme der Virulenz aufweisen (Bestande H, I und J). Der Handel von Zuchttieren sollte deshalb verboten und die Kontrolle uber die Haltungsbedingungen in den Zuchtbetrieben verscharft werden, denn klinisch gesunde Schweine, die aus solchen Bestanden stammen, konnen ebenfalls Trager von virulenten pathogenen Keimen sein. Resume Etudes epidemiologiques sur la rhinite atrophique du porc IX. Investigations sur l'introduction de la maladie Les causes d'une explosion massive de rhinite atrophique ont ete examinees en surveillant les donnees epizootogiques dans cinq grandes exploitations porcines d'engraissement (F, G, H, I, J). La surveillance epizootologique a consiste d'une part dans des recherches comparees des souches de Bordetella bronchiseptica et Pasteurella multocida, isolees avant et pendant une explosion massive, et d'autre part, dans l'etude de proprietes antigeniques et biologiques. Des animaux importes et l'etat du management ont ete controles, les symptomes cliniques et les resultats post-mortem ont ete enregistres. Les analyses de la structure antigenique ont revele que les nouvelles souches pathogenes, introduites par des animaux importes, etaient en general responsables du declenchement lorsque les souches isolees presentaient une modification de la composition antigenique capsulaire. Ces souches presenterent en general une plus grande virulence et une plus forte production d'exotoxine que les souches indigenes (exploitation F et G). Par contre, des facteurs ont pu etre attribues au management lorsque des souches isolees durant une explosion de masse ne presentaient pas de difference de structure antigenique avec des souches isolees precedemment, mais qui revelerent une nette augmentation de virulence (Exploitations H, I et J). Le commerce des animaux d'elevage a du etre interdit et les mesures de controle ont ete renforcees dans les exploitations d'elevage, car des porcs cliniquement sains, provenant de telles exploitations, pouvaient etre egalement porteurs de germes pathogenes virulents. Resumen Estudios epizootologicos sobre la rinitis atrofica del cerdo IX. Estudios sobre la incidencia y aparicion de la enfermedad En cinco explotaciones porcinas grandes (F, G, H, I, J), se estudiaron las causas de un brote masivo de rinitis atrofica mediante la vigilancia de las circunstancias epizootologicas. La vigilancia epizootologica consistia por un lado en la realizacion de estudios comparados de las estirpes de Bordetella bronchiseptica y Pasteurella multocida que fueron aisladas antes y durante el brote masivo y analizadas en cuanto a sus propiedades antigenicas y otras biologicas. Ademas se controlaron los animales importados y el estado sanitario de las empresas, registrandose los sintomas clinicos y los hallazgos post mortales. El analisis de la estructura antigenica revelo que, por lo general, eran responsables estirpes patogenas nuevas, introducidas por animales importados, de los brotes, cuando las estirpes que se aislaron en estas ocasiones mostraban una modificacion en la composicion antigenica capsular. De ordinario mostraban estas cepas una virulencia y una produccion mayor de exotoxinas que las estirpes autoctonas en las piaras (efectivos ganaderos F y G). Por otra parte se pueden hacer responsables factores que atanen a la gerencia cuando no se diferencian las estirpes aisladas durante un brote masivo en su estructura antigenica de los aislamientos anteriores, empero muestran un aumento considerable de la virulencia (efectivos ganaderos H, I y J). Por esta razon deberian estar prohibidos el comercio y trafico con animales seleccionados y recrudecerse el control relativo a las condiciones de regimen de vida en las explotaciones dedicadas a la cria, puesto que animales sanos clinicamente, que proceden de tales efectivos, tambien pueden ser portadores de germenes patogenos virulentos.

Hormone and metabolite profiles as well as the onset of ovarian cyclicity in dairy cows suffering from various forms of ketosis

Abstract: The involvement of adrenocortical and thyroid hormones in the pathogenesis of ketosis as well as the ovarian consequences of this metabolic disorder were studied in ≥2 parity cows (n=199) in 3 large scale dairy herds. To compare the plasma / serum concentrations of certain hormones [Cortisol, thyroxin (T4), triiodo-thyronine (T3), insulin, isulin-like growth factor-1 (IGF-l)J and metabolites [glucose (G), acetoacetic acid (ACAC), βOH-butyrate (BHB), non-esterified fatty acid (NEFA), trigliceride (TG), total cholesterol (TCh)J, and the activity of aspartate aminotransferase (AST), blood samples were taken 1 to 3 days after calving and again at 7-day intervals on four other occasions. The ACTH-challenged Cortisol responsiveness and the TRH-induced T4/T3 increase were determined between days 1 to 3 and again between days 28 to 35. The resumption of ovarian cyclicity was followed up by individual progesterone (P4) profiles based on milk samples taken 3 times a week for about 80 to 85 days postpartum. A concentration of 1 mmol/l of BHB level was estimated as a border between hyper- (>1 mmol/l) and normal ketonaemic (<1 mmol/l) conditions. 5 different ketone patterns were distinguished: (1) non-ketotic (n=98; normal ketonaemia in all samples), (2) early type ketosis (n=45; hyperketonemia was detected only in the first week after calving), (3) late type (lacta-tional) ketosis (n=11; after a normal ketonaemic period increasing hyperketonaemia was detected in the 5th, or in the 4th and 5th weeks), (4) temporary ketosis (n=ll; hyperketonaemia was detected for 1-2 weeks in the 2nd and 3rd or in the 3rd and 4th weeks); (5) long-lasting ketosis (n=34; hyperketonaemia had been detected since calving for 4 to 5 weeks or until death or emergency slaughtering). Simultaneously with the hyperketonaemic stage increased NEFA, ACAC, depressed TCh, glucose and decreased insulin, IGF-1, T4 and T3 concentrations were detected in almost all the cases. Obvious metabolic and endocrine alterations were found, however, only in long-lasting ketosis. The TRH-stimulated T4 and T3 responses remained almost unaffected proving intact thyroid function in early and late type as well as in temporary ketosis. Depressed thyroid response and delayed onset of cyclic ovarian function were detected only in cases of long-lasting ketosis. The cows characterized by lower than normal (< mean-SD of non-ketotic cows) ACTH-stimulated cortisol response on days 1-3 after calving showed poorer chancefor spontaneous recovery. There was a significant negative correlation between the IGF-1 level in the 1st week after calving and the duration of the postpartum acyclic period. In late type (lactational) ketosis the cessation of ovarian cyclicity was the most characteristic genital malfunction.

Detection of T-lymphocytes in the peripheral blood and lymphoid tissues of cattle using a variant of the E-rosette test and monoclonal antibodies.

Abstract: Summary A simple and efficient variant of the E-rosette test based on addition of dextran to the incubation media is described. This variant 1) does not include B cells 2) involves some CD2+ null cells as described 3) is not inhibited by anti-CD5 antibody 4) correlates with CD2 expression 5) detects specific changes in the relative proportion of T-lymphocytes under the different conditions. In a group of calves the mean percentage of RFC in the peripheral blood lymphocytes was 53.59 ± 8.70 and in cows there was 72.57 ± 3.85. The proportion of RFC detected in bovine leukemia virus (BLV) - infected cows with lymphocytosis was less than one third of that in BLV - negative animals and vice versa in B (MHC class II+) lymphocytes.

Treatment of anoestrous mares with a synthetic progestagen, allyloestrenol.

Abstract: Anoestrous mares were treated with prostaglandin (n = 43) and those that did not respond to prostaglandin (n = 29) with a synthetic progestagen, allyloestrenol, at a dose of 0.05 mg/kg body mass for 12 days. After the cessation of the long-term per os gestagen blockade the animals were checked for heat and, if a preovulatory follicle could be palpated, 2000 IU hCG was administered to induce ovulation. In some animals the plasma 17 beta-oestradiol (E2) and progesterone (P4) levels were also followed up throughout the gestagen treatment and for 10-14 days thereafter. As the favourable oestrus rate (86.2%) and pregnancy rate (65.5%) indicate, the 12-day allyloestrenol treatment seems to be a reliable tool for induction of cycling in mares anoestrous early in the season. These results, supported by the E2 and P4 profiles, suggest that an important reason for anoestrus in mares is the absence of a functional corpus luteum that can be substituted for by exogenous gestagen administration. The timing of ovulation, however, should still be improved.