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

Road transport-induced stress and its potential effects on fertility in female dogs

Dissertation - University of Veterinary Medicine Vienna - 2022 The full text is only available to university members. Please log in!In conclusion, the feeding of a high-grain diet, respectively 65% concentrate and 35% forage, decreased the faecal pH substantially as well as reduced ruminal pH. Overall, the pH did not show a continuous decrease over the course of the 4-week experimental period but remained relatively steady. This confirms the assumption, that during high concentrate feeding, larger quantities of carbohydrates can bypass the rumen resulting in the increased hindgut fermentation and reduction of both ruminal and faecal pH. The correlation between faecal and ruminal pH differs in literature, with previous reports showing a correlation of 0.5 and we could only find a correlation of 0.37. There is still a lot of research necessary about the diurnal behaviour of faeces in general but also and more importantly when cows are challenged with high-grain diets. Taking faecal samples more frequently, for example every two hours, over the period of 24 hours would give a much clearer picture in order to provide a better understanding on the behaviour of the acidity of the faeces. It is still unclear, whether the faecal pH can be used as an indicator for ruminal acidosis as found in the SARA-syndrome. This would make the detection of this illness much easier and give a better understanding of the prevalence in dairy herds. Our experiment could confirm the assumption that is widespread in literature but still shows many areas where further research is still needed.Dissertation - University of Veterinary Medicine Vienna - 2022 The full text is only available to university members. Please log in!In conclusion, the feeding of a high-grain diet, respectively 65% concentrate and 35% forage, decreased the faecal pH substantially as well as reduced ruminal pH. Overall, the pH did not show a continuous decrease over the course of the 4-week experimental period but remained relatively steady. This confirms the assumption, that during high concentrate feeding, larger quantities of carbohydrates can bypass the rumen resulting in the increased hindgut fermentation and reduction of both ruminal and faecal pH. The correlation between faecal and ruminal pH differs in literature, with previous reports showing a correlation of 0.5 and we could only find a correlation of 0.37. There is still a lot of research necessary about the diurnal behaviour of faeces in general but also and more importantly when cows are challenged with high-grain diets. Taking faecal samples more frequently, for example every two hours, over the period of 24 hours would give a much clearer picture in order to provide a better understanding on the behaviour of the acidity of the faeces. It is still unclear, whether the faecal pH can be used as an indicator for ruminal acidosis as found in the SARA-syndrome. This would make the detection of this illness much easier and give a better understanding of the prevalence in dairy herds. Our experiment could confirm the assumption that is widespread in literature but still shows many areas where further research is still needed.Dissertation - Veterinärmedizinische Universität Wien - 2022 Aus rechtlichen Gründen sind nicht alle Teile dieser Arbeit frei zugänglich. Der Zugriff auf den elektronischen Volltext ist auf Angehörige der Veterinärmedizinischen Universität Wien beschränkt. Bitte einloggen!Abschließend konnte dargestellt werden, dass bei einem gesteigerten Kraftfutteranteil im Futter, respektive 65%, der Pansen- und Fäkal-pH-Wert signifikant gesunken ist. Der pH-Wert hielt sich über den Versuchszeitraum überwiegend stabil und zeigte kein weiteres Absinken. Dies bestätigt die Annahme, dass bei starkem Zufüttern von Kraftfutter hohe Anteile an Kohlenhydraten den Pansen überwinden und erst im Enddarm fermentiert werden. Die Literaturrecherche ergab, dass die Korrelation zwischen dem Pansen- und Kot-pH-Wert umstritten ist. Gleichfalls stellte sich diese Forschungsfrage als noch nicht gänzlich erforscht dar. Neubauer et al. (2020) konnten eine Korrelation von 0.5 feststellen. Demgegenüber ergab die Betrachtung der Ergebnisse dieses Versuches lediglich einen Wert von 0.37. Ähnliche Beobachtungen ergaben sich bei der Recherche in Bezug auf die täglichen pH-Wert Schwankungen des Kots. Entsprechende Quellen, welche diese Thematik genauer erläutern, konnten ebenso nicht gefunden werden. Hinsichtlich eines besseren Verständnisses der Auswirkung hoher Kraftfutteranteile auf den pH-Wert des Kots, bedarf es weiterer Forschungstätigkeit. Es wäre beispielsweise interessant, alle zwei Stunden über den gesamten Tag gehend, Kot-Proben zu sammeln. Mit dem aktuellen Wissensstand kann keine Aussage, über die Korrelation zwischen Kot-pH-Wert und einer Erkrankung von Kühen mit SARA, getroffen werden. Dadurch wäre es Landwirten und auch Tierärzten möglich, eine genauere Prävalenz dieser oft unterschätzten Erkrankung zu erlangen. Dieser Versuch konnte die Annahme der Literatur, dass der Kot-pH-Wert bei einer kraftfutterreichen Fütterung sinkt, bestätigen. Gleichfalls konnte ein Zusammenhang zwischen einer Pansenazidose und erniedrigten Kot-pH-Wert, auf Grund des erhöhten Bypasses an Kohlenhydraten in den Enddarm, herstellen. Zusammenfassend kann festgestellt werden, dass es in diesem Bereich noch Forschungsbedarf gibt, da dem Enddarm von Rindern als Fermentationsort von Kohlenhydraten und dementsprechend auch dem Kot weitgehend wenig Aufmerksamkeit geschenkt wurde

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

Conjugated Linoleic Acids Mediate Insulin Release through Islet G Protein-coupled Receptor FFA1/GPR40*

Among dietary components, conjugated linoleic acids (CLAs) have attracted considerable attention as weight loss supplements in the Western world because they reduce fat stores and increase muscle mass. However, a number of adverse effects are also ascribed to the intake of CLAs such as aggravation of insulin resistance and the risk of developing diabetes. However, the mechanisms accounting for the effects of CLAs on glucose homeostasis are incompletely understood. Herein we provide evidence that CLAs specifically activate the cell surface receptor FFA1, an emerging therapeutic target to treat type 2 diabetes. Using different recombinant cellular systems engineered to stably express FFA1 and a set of diverse functional assays including the novel, label-free non-invasive dynamic mass redistribution technology (Corning® Epic® biosensor), both CLA isomers cis-9, trans-11-CLA and trans-10, cis-12-CLA were found to activate FFA1 in vitro at concentrations sufficient to also account for FFA1 activation in vivo. Each CLA isomer markedly increased glucose-stimulated insulin secretion in insulin-producing INS-1E cells that endogenously express FFA1 and in primary pancreatic β-cells of wild type but not FFA1−/− knock-out mice. Our findings establish a clear mechanistic link between CLAs and insulin production and identify the cell surface receptor FFA1 as a molecular target for CLAs, explaining their acute stimulatory effects on insulin secretion in vivo. CLAs are also revealed as insulinotropic components in widely used nutraceuticals, a finding with significant implication for development of FFA1 modulators to treat type 2 diabetes