Study design quality of research on dogs published in peer-reviewed journals

Background In the past it has been criticised that only a low proportion of well-designed and well-reported studies in some medical specialities is available. The objective of this study was to systematically evaluate the quality of literature about canine medicine published in peer-reviewed journals in relation to six specific veterinary medicine specialities. Methods A literature search was conducted and 25 studies per speciality were selected. The quality of the articles (n = 150) published between 2007 and 2019 was evaluated with a validated checklist. Results In articles related to all specialities, deficits were found, such as not adequate number of animals in 60.0% of the studies. In 88.0%, information about housing and feeding of the dogs were not specified. In 69.4% of the prospective clinical studies, an ethical approval was reported, and written informed consent of the owners was obtained in 46.2%. Conclusions The findings revealed extensive deficits in the design and reporting of studies in canine medicine. The demand for improvement is obvious and should be addressed by authors, reviewers and journal editors in the future. Our results underline that practitioners should critically appraise the quality of literature before implementing information into practice

Improving decision‐making in complicated or rare cases—An approach towards Evidence‐based Veterinary Medicine in small animal reproduction

The concepts of Evidence‐based Veterinary Medicine (EBVM) provide a methodological and systematic approach to include the best evidence from research into clinical decision‐making. These concepts include steps as the search and assessment of relevant research findings and consideration of individual aspects. In addition, owners and other persons involved in animal health care should be included in shared decision‐making. Some breeders have good basic knowledge concerning breeding management and characteristics of diseases and concerning advantages and disadvantages of different therapeutic approaches, while others are notable to understand complex medical interrelations or emergency situations. All these aspects need to be addressed when communicating and discussing different diagnostic, prophylactic and therapeutic options. In special fields, such as small animal reproduction, veterinarians often see animals with rare diseases or complex conditions so that an application of standard therapies and well‐established textbook recommendations is not possible. To learn more about cases too rare for successful systematic research, the case collection tool REPROCASES (www.evssar.org/reprocases) is now available. The aim of this project is to gather information from specialists on small animal reproduction in a multicentre approach. If you see rare or not well‐investigated cases such as cystic ovarian diseases, cryptorchidism or others, you are more than welcome to share your findings via the database. Even if this approach cannot completely replace standardized clinical trials, the idea is to gather more information on effects, prognosis, side effects and long‐term fertility for specific conditions

The metabolic differences of anestrus, heat, pregnancy, pseudopregnancy, and lactation in 800 female dogs

IntroductionReproduction causes major hormonal and physiological changes to the female body. However, the metabolic changes occurring during canine reproduction are scarcely studied. MethodsIn this cross-sectional study, we assessed the metabolic effects of canine reproductive status using a H-1 NMR metabolomics platform optimized and validated for canine use. The study population consisted of a total of 837 healthy, intact female dogs in breeding age, of which 663 dogs were in anestrus, 78 in heat, 43 were pseudopregnant, 15 were pregnant, and 38 were lactating. The differences in metabolite profiles between these states were studied by the Kruskal-Wallis test with post-hoc tests performed using the Dunn's test, and visualized by box plots and a heatmap. The ability of the metabolite profile to differentiate pregnant dogs from non-pregnant ones was assessed by creating a multivariate Firth logistic regression model using forward stepwise selection. ResultsLactation, pregnancy and heat all were associated with distinct metabolic changes; pregnancy caused major changes in the concentrations of glycoprotein acetyls, albumin and creatinine, and smaller changes in several lipids, citrate, glutamine, and alanine. Pseudopregnancy, on the other hand, metabolically largely resembled anestrus. Lactation caused major changes in amino acid concentrations and smaller changes in several lipids, albumin, citrate, creatinine, and glycoprotein acetyls. Heat, referring to proestrus and estrus, affected cholesterol and LDL metabolism, and increased HDL particle size. Albumin and glycoprotein acetyls were the metabolites included in the final multivariate model for pregnancy detection, and could differentiate pregnant dogs from non-pregnant ones with excellent sensitivity and specificity. DiscussionThese results increase our understanding of the metabolic consequences of canine reproduction, with the possibility of improving maternal health and ensuring reproductive success. The identified metabolites could be used for confirming canine pregnancy.Peer reviewe

Top 5 Tips for Reading a Veterinary Scientific Study

Results from scientific research can help provide optimal care. Daily decisions should lead to effective diagnostic procedures and therapeutic interventions with optimal risk:benefit ratios. It is therefore important to be able to select and evaluate scientific literature relevant to the field and/or patient. Critical evaluation aids in identification of strengths and weaknesses of a study and its relevance and validity in the clinic1; relevant information for critical evaluation is typically found in the methods and results sections

The metabolic differences of anestrus, heat, pregnancy, pseudopregnancy, and lactation in 800 female dogs

Introduction: Reproduction causes major hormonal and physiological changes to the female body. However, the metabolic changes occurring during canine reproduction are scarcely studied. Methods: In this cross-sectional study, we assessed the metabolic effects of canine reproductive status using a 1H NMR metabolomics platform optimized and validated for canine use. The study population consisted of a total of 837 healthy, intact female dogs in breeding age, of which 663 dogs were in anestrus, 78 in heat, 43 were pseudopregnant, 15 were pregnant, and 38 were lactating. The differences in metabolite profiles between these states were studied by the Kruskal-Wallis test with post-hoc tests performed using the Dunn's test, and visualized by box plots and a heatmap. The ability of the metabolite profile to differentiate pregnant dogs from non-pregnant ones was assessed by creating a multivariate Firth logistic regression model using forward stepwise selection. Results: Lactation, pregnancy and heat all were associated with distinct metabolic changes; pregnancy caused major changes in the concentrations of glycoprotein acetyls, albumin and creatinine, and smaller changes in several lipids, citrate, glutamine, and alanine. Pseudopregnancy, on the other hand, metabolically largely resembled anestrus. Lactation caused major changes in amino acid concentrations and smaller changes in several lipids, albumin, citrate, creatinine, and glycoprotein acetyls. Heat, referring to proestrus and estrus, affected cholesterol and LDL metabolism, and increased HDL particle size. Albumin and glycoprotein acetyls were the metabolites included in the final multivariate model for pregnancy detection, and could differentiate pregnant dogs from non-pregnant ones with excellent sensitivity and specificity. Discussion: These results increase our understanding of the metabolic consequences of canine reproduction, with the possibility of improving maternal health and ensuring reproductive success. The identified metabolites could be used for confirming canine pregnancy

Diagnostic tests in canine andrology - What do they really tell us about fertility?

Dog breeders often require breeding soundness evaluations which include andrological examinations of the genital organs, hormone measurements, and semen analyses. During the past decades, a considerable number of research results have been published, allowing diagnoses of specific andrological conditions and fertility assessment. For specific examinations, however, no standard procedures have been defined and for some parameters different reference ranges have been published. Therefore, examination results from different facilities are difficult to compare and profound conclusions regarding health and fertility of a male dog are not always possible. Conventional semen examination, however, is still useful in identifying deviations or no deviations from normality, especially if confounding factors are taken into account and if the exam is repeated in case of inconclusive findings. A standardization of examination procedures and reference ranges would help to harmonize the exchange of examination results and interpretation of the findings

Teaching small animal reproduction via virtual patients

Virtual patients have become an interesting alternative in medical education. Due to increasing demands regarding theoretical and clinical teaching and to improve an interdisciplinary approach, a new blended learning concept including virtual patients was developed and implemented in the veterinary curriculum of the Freie Universität Berlin. In the presented project, three virtual patients from the field of canine reproduction were developed. They focus on pregnancy diagnosis with suspected luteal insufficiency, pyometra and benign prostatic hyperplasia, respectively. The results of an evaluation by veterinary students of the 7th semester showed a high acceptance of virtual patients in a blended learning reproduction module in the interdisciplinary lectures. Students especially preferred videos, such as video lectures, hands‐on videos and animations as well as a glossary for background information, to successfully and autonomously work on a virtual case. The content covered by the new modules that were developed in the context of this project is part of a spiral curriculum; they will be revised and enhanced during the clinical year

Metabolomics during canine pregnancy and lactation

During pregnancy and parturition, female dogs have to cope with various challenges such as providing nutrients for the growth of the fetuses, hormonal changes, whelping, nursing, milk production, and uterine involution. Metabolomic research has been used to characterize the influence of several factors on metabolism such as inter- and intra-individual factors, feeding, aging, inter-breed differences, drug action, behavior, exercise, genetic factors, neuter status, and pathologic processes. Aim of this study was to identify metabolites showing specific changes in blood serum at the different phases of pregnancy and lactation. In total, 27 privately owned female dogs of 21 different breeds were sampled at six time points: during heat, in early, mid and late pregnancy, at the suspected peak of lactation and after weaning. A validated and highly automated canine-specific NMR metabolomics technology was utilized to quantitate 123 measurands. It was evaluated which metabolite concentrations showed significant changes between the different time points. Metabolites were then grouped into five clusters based on concentration patterns and biochemical relationships between the metabolites: high in mid-pregnancy, low in mid-pregnancy, high in late pregnancy, high in lactation, and low in lactation. Several metabolites such as albumin, glycoprotein acetyls, fatty acids, lipoproteins, glucose, and some amino acids show similar patterns during pregnancy and lactation as shown in humans. The patterns of some other parameters such as branched-chain amino acids, alanine and histidine seem to differ between these species. For most metabolites, it is yet unstudied whether the observed changes arise from modified resorption from the intestines, modified production, or metabolism in the maternal or fetal tissues. Hence, further species-specific metabolomic research may support a broader understanding of the physiological changes caused by pregnancy that are likely to be key for the normal fetal growth and development. Our findings provide a baseline of normal metabolic changes during healthy canine pregnancy and parturition. Combined with future metabolomics findings, they may help monitor vital functions of pre-, intra-, and post-partum bitches and may allow early detection of illness

Progesterone Concentrations during Canine Pregnancy

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