Use of dried blood smears for detection of feline hemoplasmas using real-time polymerase chain reaction

The objective of the current study was to determine the sensitivity and specificity of real-time polymerase chain reaction (real-time PCR) for feline hemoplasmas when applied to DNA extracted from dried whole-blood smears in comparison to that for DNA extracted from liquid whole blood. Blood samples were collected into ethylenediamine tetra-acetic acid tubes from 305 cats with possible or suspected hemoplasmosis, and dried blood smears from each sample were prepared. DNA was extracted from blood smears and a 160-microl aliquot of each liquid blood sample by using a robotic extractor and was subjected to real-time PCR for feline glyceraldehyde-3-phosphate dehydrogenase (liquid blood), 18S ribosomal RNA (dried blood), and "Candidatus Mycoplasma haemominutum", Mycoplasma haemofelis, and "Candidatus Mycoplasma turicensis" DNA. When using the results for liquid whole blood as the gold standard, the sensitivity of each assay for "Ca. M. haemominutum", M. haemofelis, and "Ca. M. turicensis" was 49 of 66 (74%), 11 of 13 (85%), and 11 of 20 (55%), respectively. The specificity of each assay was 224 of 234 (96%), 287 of 287 (100%), and 280 of 280 (100%), respectively. When possible, liquid blood samples should be submitted for detection of feline hemoplasmas by using real-time PCR. The improved sensitivity of real-time PCR on blood smears for M. haemofelis compared with that of the other hemoplasma species may reflect the higher organism burdens associated with infection with this species.     

The increasing risk of Lyme disease in Canada

There is an increasing risk of Lyme disease in Canada due to range expansion of the tick vector, Ixodes scapularis. The objectives of this article are to i) raise public awareness with the help of veterinarians on the emerging and expanding risk of Lyme disease across Canada, ii) review the key clinical features of Lyme disease in dogs, and iii) provide recommendations for veterinarians on the management of Lyme disease in dogs.     

Nasopharyngeal myxosarcoma in a Bengal tiger (Panthera tigris).

An 18- to 25-yr-old intact female Bengal tiger (Panthera tigris) was diagnosed antemortem and postmortem with nasopharyngeal myxosarcoma metastatic to the lung, chronic lymphoplasmacytic otitis media, and lymphoplasmacytic and eosinophilic stomatitis. Myxosarcomas are rare in domestic animals and seldom metastasize; this tumor has not been previously reported in an exotic felid. Computed tomography of the skull was used during the diagnoses.     

Molecular basis of globoid cell leukodystrophy in Irish setters

Globoid cell leukodystrophy (GLD), or Krabbe's disease, is a progressive autosomal recessive disorder of the central nervous system in man and in various other species. GLD has been shown to result from various mutations in the gene encoding galactocerebrosidase (GALC), a lysosomal enzyme. We investigated the molecular basis of GLD in a related group of Irish setters. Sequencing of the GALC cDNA from an affected individual revealed an insertion mutation of 78 base pairs (bp) consisting of 16 bp of insertion site duplication and 62 bp of sequence derived from the U4 small nuclear RNA. We implemented a PCR-based test which is useful for identifying carriers of the mutation.     

Protection of cattle against heartwater in Botswana: comparative efficacy of different methods against natural and blood-derived challenges

Five groups of Tswana-cross castrated male cattle between 20 and 30 months of age (a total of 158 animals) were transported from a ranch in a heartwater-free area of south Botswana to a feedlot near Gaborone in the east of Botswana where heartwater is endemic. On arrival, one group was vaccinated intravenously with the Onderstepoort sheep blood heartwater vaccine, one group was vaccinated intravenously with the new Onderstepoort tick-derived heartwater vaccine and a third group was vaccinated subcutaneously with this tick-derived vaccine. Vaccine reactions were blocked with long acting oxytetracycline on the first day of fever. A fourth group had a series of injections of long acting oxytetracycline on days 0, 7, 14 and 21 after arrival, and a fifth served as untreated controls. The animals remained at the feedlot for 65 days during which time they faced a low level of challenge by Amblyomma hebraeum ticks. None contracted heartwater and so they were then challenged, together with a further group of control cattle, with a dose of the sheep blood vaccine. Some animals in all groups had severe heartwater reactions and died despite therapy, but 76.7 per cent, 64.5 per cent and 74.3 per cent of the cattle in the blood vaccine, intravenous tick vaccine and long acting oxytetracycline groups respectively were resistant to challenge, compared with 48.3 per cent of the subcutaneous tick vaccine group and 36.4 per cent of the controls. It was concluded that intravenous vaccination of susceptible adult cattle with either the blood or the tick-derived vaccine needs careful monitoring in the month after vaccination and does not necessarily result in immune animals.(ABSTRACT TRUNCATED AT 250 WORDS)     

The space requirement of potatoes in pallet boxes and the weight loss of such potatoes during storage

Summary Over a period of 3 years potatoes in pallet based boxes, having a nominal capacity of 1016 and 508 kg, were weighed as they were placed in and removed from a ventilated store. A total of 136 boxes were weighed and a value of 1.4 m³/ton can be used for estimating the capacity of such boxes. Average weight loss/day of potatoes in the stores was between 0.03 and 0.05%. The weight loss from the individual boxes varied from 2.4 to 14.6% over a storage period of 95 to 262 days.

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Zusammenfasung Es ist wichtig, den Raumbedarf von in Kisten gelagerten Kartoffeln zu bestimmen, weil dieser Faktor einen Einfluss auf die Konstruktion eines Kartoffellagers, sowohl in Bezug auf das Gewicht der eingelagerten Kartoffeln als auch auf die n?tige W?rnmeabführung, ausüben kann. Auf zwei Betrieben wurde eine dreij?hrige Untersuchung durchgeführt, wobei die Kartoffeln in auf Paletten gestellten Kisten eingelagert waren. Die Kartoffellagerr?ume wurden mit Klimaanlagen ausgerüstet, und die Temperatur wurde zwischen 7 und 10°C gehalten. Zwei Kistengr?ssen mit einem Rauminhalt von 1016 und 508 kg wurden benutzt. Die Kisten einschliesslich Inhalt wurden bei der Ein- und Auslagerung gewogen. Der Raumbedarf der Kartoffeln war 1,4 m³/ 1000 kg für die beiden Kistengr?ssen (Tabelle 1). Der Gewichtsverlust der Kartoffeln in den Lagern belief sich auf 0,02–0.05% pro Tag. Gem?ss der Einlagerungsperiode von 95–262 Tagen lag der gesamte Verlust in den Kisten im Bereich von 2,4–14,6% (Tabelle 2). Im Herbst 1968 war das Wetter so nass, dass ein überm?ssiger Anteil an Erde mit den Kartoffeln in die Kisten gefüllt wurde. Bei den gr?sseren Kisten betrug das Nettogewicht der Kartoffeln nur 305–464 kg, d.h. unter ungünstigen Erntebedingungen k?nnte bis zur H?lfte des Inhalts eines Kartoffellagers aus Erde bestehen.

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Résumé Il est important de déterminer l'espace occupé par les pommes de terre stockées en caisses-palettes, cette donnée pouvant influencer la construction des entrepots sant du point de vue poids de pommes de terre stockées que de la quantité de chaleur à évacuer. Pendant trois années, des études ont été poursuivies dans deux fermes dans lesquelles des pommes de terre étaient stockées en caisses-palettes placées dans des entrep?ts aérés où la température contr?lée variait de 7 à 10 C. Deux types de caisses furent utilisées dont la capacité normale était de 1016 kg et 508 kg. On a pesé les caisses avec leur contenu à l'entrée et à la sortie de l'entrep?t. L'exigence en espace était de 1,4m³ pour 1000 kg de pommes de terre pour les deux types de caisses (Tableau 1). La perte de poids pour les deux types de caisses était de 0,03–0,05% par jour tandis que celle-ci pour période de stockage de 95 à 262 jours variait de 2,4 à 14,6% (Tableau 2). En automne 1968, les conditions atmosphériques étaient tellement humides qu'une quantité exagérée de terre remplissait les caisses avec les pommes de terre. Dans le cas des caisses les plus grosses le poids net des pommes de terre était seulement de 305–464 kg; ainsi dans des conditions défavorables de récolte, une quantité allant jusqu'à la moitié du contenu d'une caisse peut être constituée de terre.

     

Development of Isospora suis from pigs in primary porcine and bovine cell cultures

Sporozoites of Isospora suis penetrated and developed by endodyogeny in primary porcine kidney (PPK) and primary fetal bovine kidney (PFBK) cell cultures. Motile merozoites and binucleate Type I meronts were observed in both types of cultured cells. Multinucleate Type II meronts developed in PPK cell cultures only. These multinucleate meronts were always found singly, were nonmotile and did not form merozoites.     

The effect of weaning method on coccidial infections in beef calves

Weaning is often cited as a stressful event that can precipitate clinical coccidiosis in cattle. Recently, two-stage weaning methods have been investigated as a means to reduce stress in calves. The objective of this study was to investigate the effect of weaning method on fecal oocyst count (FOC) and Eimeria spp. composition. A group of 108 beef calves (190-240 days of age) were allocated to three treatments on day -7: a fenceline weaned group where calves could see and hear their dams, but were physically separated from them by a fence (FL), a noseclipped group where suckling was prevented (NC), and a group left with their dams to be traditionally weaned (TW) by abrupt separation on day 0. On day 0, noseclips were removed from the NC calves and all groups were completely separated from their dams. The steers (n=50) were transported 172 km to another farm, and heifers (n=58) were taken to distant fields on the same farm. Rectal fecal samples were collected from all calves on days -7, 0, and 14. Steers were also sampled on days 7, 28, and 42. A group of steers (n=24) from each of the treatments previously described were fitted with pedometers and intensively observed on days 1-4. The Modified McMaster's test and Wisconsin sugar flotation test were used for quantification and identification of Eimeria spp. oocysts. Clinical coccidiosis was not observed during the study. Fecal oocyst counts did not differ between treatment groups on any sampling day. Differences between steer and heifer FOC were not detected. Treatment had no effect on species composition, but time effects were detected in the steers. The mean percentage of E. bovis was lower (P<0.05) on days 28 and 42 than all other sampling days. The decrease in the percentage of E. bovis was accompanied by an increase (P<0.05) in the percentage of E. canadensis on days 28 and 42. Behavioral observation showed that TW steers exhibited higher levels of stress related behavior (P<0.05) following complete separation, although this was not reflected in FOC.