Pregnancy and lactation are amongst the most challenging times of a bitch’s life. Most studies focusing on the endocrinological aspect of pregnancy consider only a small number of animals. The aim of this study was to evaluate progesterone (P4) concentrations in a large number of bitches during early, mid and late pregnancy. In total, 126 bitches of various breeds were recruited following a thorough clinical and gynecological examination during estrus. Blood samples were collected three times (T1–T3) during pregnancy or from non-pregnant dogs in diestrus, and P4 was measured via chemiluminescence. At T1 (11–19 days post-ovulation (dpo)), serum P4 concentrations were 30.23 ± 6.65 ng/mL and 28.45 ± 6.26 ng/mL, at T2 (23–32 dpo) they were 22.73 ± 6.27 ng/mL and 22.59 ± 5.77 ng/mL and at T3 (52–60 dpo) they were 6.68 ± 2.18 ng/mL and 3.17 ± 2.26 ng/mL, in pregnant (n = 98) and non-pregnant (n = 23) dogs respectively. The P4 concentrations differed significantly between pregnant and non-pregnant animals at the last examination (p ≤ 0.001). In the context of hypoluteoidism, the gathered data yielded interesting results. Overall, 28 out of 98 pregnant bitches showed a greater decline (>15 ng/mL) in P4 concentrations from early to mid-pregnancy, and 56 bitches showed P4 concentrations lower than deemed adequate (>20 ng/mL at T1 and T2, >5 ng/mL at T3) according to existing recommendations. Despite not being supplemented with P4, none of those animals suffered from abortion or preterm delivery. Considering that supplementation of P4 can entail considerable risks for the bitch and the puppies, more research on P4 concentration patterns, diagnosis of hypoluteoidism and treatment indications and options is indicated.
Vaginal cytology is an important examination method in the context of gynecological disorders and cycle staging in the bitch. While collection and preparation of samples are easy, the evaluation appears to be challenging. Inconsistent definitions of cell attributes such as size, cornification and the appearance of the nucleus have been published. The aim of the project was to develop a tutorial for vaginal cell determination. To get a deeper insight into the use of cytology in practice, an online survey was distributed to veterinarians interested in small animal reproduction. Participants were asked to define eight cells and answer questions. The agreement of the 16 participants, working in eight different countries, determining the cells was poor (κ = 0.412). Eleven respondents stated that vaginal cytology has a low reliability. Nevertheless, 13 participants use this tool regularly. The tutorial was developed as a flowchart based on the survey results, scientific literature and own measurements. It guides the user systematically through the evaluation of specific cell characteristics. An evaluation of the results of five raters with difference experience levels led to a high agreement (κ = 0.858). Vaginal cytology is a useful diagnostic tool, but it seems helpful to standardize the determination of cell types.
25 November 2018 in Reproduction in Domestic Animals
Ovulation timing in bitches is a routine procedure in small animal practice around the world. It is most frequently used for supporting breeding management, high‐risk pregnancy monitoring and determination of the time of parturition. To learn more about how and for what reasons veterinarians interested in small animal reproduction perform canine ovulation timing, an online survey was conducted in 2017. The link to the survey was distributed via the mailing list cafereprod-l@list.cornell.edu and the website, the Twitter account and the Facebook page of EVSSAR. All respondents recommended using quantitative progesterone measurement for ovulation timing alone or in combination with other diagnostic tests. Vaginal cytology was also a commonly used technique. The 63 respondents followed different protocols for sampling and staining vaginal epithelial cells. Interestingly, 50 respondents used vaginal cytology routinely, but only two consider it as a very reliable and another nine as a somewhat reliable test if used alone. In a second project, delegates attending the EVSSAR congress held in Vienna, Austria, in June 2017 had the opportunity to examine seven stained vaginal smear slides under optical microscopy in a blinded approach. The results showed a marked heterogeneity in the identification of vaginal cells and assessment of the time in relation to ovulation. This heterogeneity supports the opinion of survey participants that vaginal cytology alone is not a valid tool for determining the day of ovulation. Results of both projects suggest that there is no standard procedure for the examination of vaginal smears in dogs. It is not recommended to determine the optimal time for mating based on the examination of a single vaginal smear only. According to some comments of survey participants, it is more useful to assess vaginal samples repeatedly and to use the findings to determine when to start progesterone measurement.
Background: Veterinary practitioners and clinicians should base their clinical decisions on the best evidence obtainable to provide best patient care. The evidence of information concerning diagnostic or therapeutic procedures and disease prevention can be ranked from weak to strong based on the methodology the information is generated by. Teaching the concepts and strategies of Evidence-based Veterinary Medicine, however, can be challenging. Students and practitioners should become competent in defining a clinical problem, retrieving of information from the literature and independent critical thinking. Several authors illustrated the levels of evidence ranked from strongest to weakest using a pyramid metaphor. The basis reflects information of the lowest evidence and towards the tip the evidence increases. The metaphorical concept of the pyramid, i.e. solid foundation and a narrow tip, however, does not adequately represent the hierarchy of evidence as the high evidence levels are represented by narrow fields and vice versa. Results: We propose an alternative schematic which may be used in order to display the respective evidence levels as a staircase. A reading pictogram character illustrates that the search for information should start at the highest step. To assess which metaphor can be more easily interpreted and is intuitively accessible a survey among 5th semester veterinary students was performed which was completed by 100 respondents. According to the results both metaphors adequately display the hierarchy of evidence. The staircase better represents the fact that high evidence information is more likely to be true and that one should start to look for high evidence when searching information. In contrast more students found that the pyramid represents distracting information i. e. that opinions and information from the internet provide a solid knowledge base. Conclusions: The staircase of evidence displays better the evidentiary value of information and how to perform a search for information of high evidence compared to the pyramid of evidence. It therefore can help to teach information search and interpretation strategies in order to answer specific clinical questions.
12 October 2017 in Tierärztliche Praxis Ausgabe K: Kleintiere / Heimtiere
Zusammenfassung: Die Beratung von Hundehaltern bezüglich der Vorteile und Nachteile sowie des optimalen Zeitpunktes der Kastration einer Hündin ist komplex und sollte sich auf verlässliche Daten aus der Wissenschaft stützen sowie individuelle Belange berücksichtigen. Bei genauerer Betrachtung der aktuellen Publikationen zu diesem Thema fällt auf, dass einige lange für robust gehaltene Informationen etwas angepasst oder aktualisiert werden müssen. Ein offensichtlicher Vorteil der elektiven Kastration ist, dass Erkrankungen der Ovarien und sexualsteroidabhängige Erkrankungen wie Metropathien nicht auftreten. Weiterhin ist ein gewisser protektiver Effekt einer frühzeitigen Kastration auf die Entstehung von Mammatumoren anzunehmen, wenngleich dafür derzeit eine schwache wissenschaftliche Evidenz besteht und der Effekt vermutlich geringer ausfällt, als in einigen älteren Publikationen angegeben wurde. Die Kastration hat jedoch auch Nachteile. Als häufigste negative Folge wird seit Jahrzehnten die Harninkontinenz beschrieben. Aussagen zur Inzidenz sowie zu weiteren Einflussfaktoren, wie Kastrationszeitpunkt in Bezug zur Pubertät, sind jedoch uneinheitlich. Aktuell werden vor allem das gehäufte Auftreten verschiedener Tumorerkrankungen, die nicht direkt mit dem Reproduktionstrakt in Verbindung stehen, sowie ein höheres Risiko für Erkrankungen des Bewegungsapparats bei kastrierten Tieren diskutiert. Weitere Einflussfaktoren wie der Ernährungszustand des Hundes, Alter und/oder Haltung wurden jedoch häufig nicht erfasst. Die Datenlage zur Auswirkung der Kastration auf den Stoffwechsel und das Immunsystem der Hündin ist derzeit ungenügend. Wünscht der Tierbesitzer eine Kastration, bedarf es in jedem Fall einer eingehenden Beratung, die individuelle, rasse- und haltungsbezogene Aspekte einschließt. Derzeit ist eine Kastration am ehesten zwischen der ersten und zweiten Läufigkeit zu empfehlen, da ein gewisser protektiver Effekt auf die Entstehung von Mammatumoren anzunehmen ist und das Risiko unerwünschter Nebenwirkungen nach heutigem Wissensstand moderat ausfällt.