Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic informat... more Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic information on these abnormalities must be generated. Objectives To characterize the metabolic changes associated with elevated fructosamine, reflecting poor glycemic control, and low thyroxine, a thyroid hormone controlling metabolism. Methods Leftovers of clinical serum samples; 25 controls, 79 high fructosamine, and 47 low thyroxine, were analyzed using 1H NMR and differences were evaluated using Firth logistic regression. Results Both high fructosamine and low thyroxine were associated with changes in concentrations of multiple metabolites, including glycoprotein acetyls and lipids. Conclusion These findings suggest promising makers for further research and clinical validation.
The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility i... more The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility is not fully understood. We used the downregulated testis as a model of gonadotropin-dependent infertility. Serum testosterone and AMH concentrations were studied in five adult male Beagles implanted (day 0) with 4.7 mg deslorelin (Suprelorin®, Virbac) (DES group). Testicular expression of LH receptor (LHR) and androgen receptor (AR), AMH, type 2 AMH receptor (AMHR2), INSL3 and its receptor (RXFP2) was evaluated 112 days (16 weeks) after deslorelin treatment by qPCR and immunohistochemistry, and compared to untreated adult (CON, n = 6) and prepubertal (PRE, n = 8) dogs. Serum testosterone concentration decreased significantly by the onset of aspermia on study day 14 (four dogs) or day 21 (one dog), and was baseline on day 105 (week 15). In contrast, serum AMH started to increase only after the onset of aspermia and reached the maximum detectable concentration of the assay by day 49-105 in individual dogs. Testicular LHR gene expression in DES was lower than in CON and PRE (P < 0.0001), while AR gene expression in DES was similar to CON and significantly higher than PRE (P < 0.0001). Testicular AMH expression in DES was intermediate compared to the lowest mRNA levels found in CON and the highest in PRE (P ≤ 0.006). AMHR2 gene expression was similar between groups. AMH protein was detected in Sertoli cells only, while AMHR2 immunoreactivity was principally detected in Leydig cells which appeared to be increased in DES. INSL3 and RXFP2 gene expression was significantly downregulated in the DES testis along with noticeably weak Leydig cell immunosignals compared to CON. In conclusion, deslorelin treatment caused testicular LH insensitivity without affecting androgen sensitivity, and de-differentiation of Sertoli and Leydig cells. In DES, upregulation of the AMH-AMHR2 feed-back loop and downregulation of the INSL3-RXFP2 feed-forward loop are paracrine-autocrine mechanisms that may additionally regulate testosterone production independent of gonadotropins. Our results support AMH and INSL3 as unique biomarkers and paracrine-autocrine regulators of testis function involved in the intimate interplay between Sertoli and Leydig cells.
S evere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the ongoing coronavir... more S evere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the ongoing coronavirus disease (COVID-19) pandemic, causes high rates of illness and death among humans. SARS-CoV-2 is a newly recognized member of the genus Betacoronavirus, family Coronaviridae, that infects humans. An early serosurvey among domestic cats in Wuhan, China, during January-March 2020 reported 14.7% seropositivity (1). Experimental infections demonstrated susceptibility to SARS-CoV-2 infection in cats and other carnivore species, such as ferrets (Mustela putorius furo), minks (Neovison vison), and to a lesser extent domestic dogs (2,3), and confi rmed anecdotal observations of naturally occurring human-to-animal transmissions (4,5). Respiratory and gastrointestinal signs were observed in SARS-CoV-2-infected cats (6-8). We conducted a seroprevalence study for SARS-CoV-2-specifi c antibodies among domestic cats in Europe during and after the fi rst COVID-19 pandemic wave, using a plaque-reduction virus neutralization test (VNT) and a SARS-CoV-2 receptor-binding domain-specifi c ELISA (RBD-ELISA). We analyzed serum samples collected from 2,160 domestic cats during April-June 2020. Samples had been sent to a veterinary diagnostic laboratory (LABOklin; Kissingen, Germany) for diagnostic purposes unrelated to suspicion of SARS-CoV-2 infection (9). Samples were from 1,136 cats in Germany, 331 in the United Kingdom, 333 in Italy, and 360 in Spain. Among 1,799 samples with demographic data, cats ranged from 0.1-23 years of age (median and mean age 11 years). We estimated a minimum of 300 total samples per location to enable a realistic estimation for each location. To confi rm specifi city of the assays to detect SARS-CoV-2-specifi c antibodies, we included 25 prepandemic cat serum samples and 25 serum samples from cats that tested positive for feline coronavirus/feline infectious peritonitis ( FCoV/FIP) by NovaTec VetLine (Novatec Immundiagnostica GmbH, ), a commercial antibody test, in the screening. We tested all serum samples by VNT, as previously described (10). We considered serum samples positive when titers were >20, expressed as the reciprocal of the dilution that gave >80% reduction of stained cells in the plaque reduction neutralization test (PRNT 80 ) (Appendix, EID/article/27/12/21-1252-App1.pdf). We also tested serum samples with an indirect ELISA we developed and validated inhouse. We used an ELISA previously used for detecting SARS-CoV-2 RBD antibodies in human serum (11) and replaced the anti-human IgG conjugate with an anti-cat IgG conjugate (Appendix). We evaluated performance characteristics of the cat ELISA-RBD by using Pearson correlation of the results obtained by ELISA-RBD and Gaussian distribution analyses for the VNT. We also calculated
Studies in female dogs proved the measurement of anti-Müllerian hormone (AMH) as a diagnostic too... more Studies in female dogs proved the measurement of anti-Müllerian hormone (AMH) as a diagnostic tool to distinguish ovarioectomized from intact females or to diagnose ovarian remnant syndrome. Furthermore, its usability to diagnose a granulosa cell tumour and predict litter size was also investigated in female dogs. Although serum AMH was previously shown to increase during the transition from anoestrus to pro-oestrus in dogs, changes in AMH concentration over the entire M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT clearly distinguish between intact and spayed females and that the serum AMH pattern over the oestrous cycle is similar in all bitches, but with high variation among the breeds and among and within bitches. These changes in the AMH concentration are a challenge in timing serum sample collection and interpreting AMH values in bitches. Further studies are necessary to emphasize the factors influencing the AMH concentration.
Control of luteal regression in the dog is still poorly understood. Unlike other domestic animal ... more Control of luteal regression in the dog is still poorly understood. Unlike other domestic animal species, luteolysis is not prevented by hysterectomy. Indications that PGF 2␣ may act as an endogenous luteolytic agent have been found only in pregnant animals during the prepartal decline of progesterone. Evidence from several species indicates that the immune system plays an important role in corpus luteum (Cl) function, possibly by the release of cytokines from immigrant immune cells. Hence, in the present experiment we attempted to examine the expression of cytokines in the canine Cl during the course of dioestrus (formation and regression of the Cl), using RT-PCR. Groups of 4-5 bitches were ovario-hysterectomised on days 5, 15, 25, 35, 45 and 60-80 after ovulation.
Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an ei... more Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an eine Laboruntersuchung ist es, die zugrunde liegende Fragestellung möglichst konkret zu beantworten. Dies ist unabhängig davon, ob die Probe im praxis- bzw. klinikeigenen oder aber in einem Versandlabor untersucht wird. Die Messergebnisse sollten die physiologische bzw. pathologische Situation des Tieres zum Zeitpunkt der Probennahme möglichst genau widerspiegeln. Der Beitrag informiert darüber, was es zu beachten gibt.
Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic informat... more Introduction Metabolomics studies in canine endocrine abnormalities are sparse and basic information on these abnormalities must be generated. Objectives To characterize the metabolic changes associated with elevated fructosamine, reflecting poor glycemic control, and low thyroxine, a thyroid hormone controlling metabolism. Methods Leftovers of clinical serum samples; 25 controls, 79 high fructosamine, and 47 low thyroxine, were analyzed using 1H NMR and differences were evaluated using Firth logistic regression. Results Both high fructosamine and low thyroxine were associated with changes in concentrations of multiple metabolites, including glycoprotein acetyls and lipids. Conclusion These findings suggest promising makers for further research and clinical validation.
The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility i... more The role of anti-Müllerian hormone (AMH) and insulin-like peptide 3 (INSL3) in male infertility is not fully understood. We used the downregulated testis as a model of gonadotropin-dependent infertility. Serum testosterone and AMH concentrations were studied in five adult male Beagles implanted (day 0) with 4.7 mg deslorelin (Suprelorin®, Virbac) (DES group). Testicular expression of LH receptor (LHR) and androgen receptor (AR), AMH, type 2 AMH receptor (AMHR2), INSL3 and its receptor (RXFP2) was evaluated 112 days (16 weeks) after deslorelin treatment by qPCR and immunohistochemistry, and compared to untreated adult (CON, n = 6) and prepubertal (PRE, n = 8) dogs. Serum testosterone concentration decreased significantly by the onset of aspermia on study day 14 (four dogs) or day 21 (one dog), and was baseline on day 105 (week 15). In contrast, serum AMH started to increase only after the onset of aspermia and reached the maximum detectable concentration of the assay by day 49-105 in individual dogs. Testicular LHR gene expression in DES was lower than in CON and PRE (P < 0.0001), while AR gene expression in DES was similar to CON and significantly higher than PRE (P < 0.0001). Testicular AMH expression in DES was intermediate compared to the lowest mRNA levels found in CON and the highest in PRE (P ≤ 0.006). AMHR2 gene expression was similar between groups. AMH protein was detected in Sertoli cells only, while AMHR2 immunoreactivity was principally detected in Leydig cells which appeared to be increased in DES. INSL3 and RXFP2 gene expression was significantly downregulated in the DES testis along with noticeably weak Leydig cell immunosignals compared to CON. In conclusion, deslorelin treatment caused testicular LH insensitivity without affecting androgen sensitivity, and de-differentiation of Sertoli and Leydig cells. In DES, upregulation of the AMH-AMHR2 feed-back loop and downregulation of the INSL3-RXFP2 feed-forward loop are paracrine-autocrine mechanisms that may additionally regulate testosterone production independent of gonadotropins. Our results support AMH and INSL3 as unique biomarkers and paracrine-autocrine regulators of testis function involved in the intimate interplay between Sertoli and Leydig cells.
S evere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the ongoing coronavir... more S evere acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the ongoing coronavirus disease (COVID-19) pandemic, causes high rates of illness and death among humans. SARS-CoV-2 is a newly recognized member of the genus Betacoronavirus, family Coronaviridae, that infects humans. An early serosurvey among domestic cats in Wuhan, China, during January-March 2020 reported 14.7% seropositivity (1). Experimental infections demonstrated susceptibility to SARS-CoV-2 infection in cats and other carnivore species, such as ferrets (Mustela putorius furo), minks (Neovison vison), and to a lesser extent domestic dogs (2,3), and confi rmed anecdotal observations of naturally occurring human-to-animal transmissions (4,5). Respiratory and gastrointestinal signs were observed in SARS-CoV-2-infected cats (6-8). We conducted a seroprevalence study for SARS-CoV-2-specifi c antibodies among domestic cats in Europe during and after the fi rst COVID-19 pandemic wave, using a plaque-reduction virus neutralization test (VNT) and a SARS-CoV-2 receptor-binding domain-specifi c ELISA (RBD-ELISA). We analyzed serum samples collected from 2,160 domestic cats during April-June 2020. Samples had been sent to a veterinary diagnostic laboratory (LABOklin; Kissingen, Germany) for diagnostic purposes unrelated to suspicion of SARS-CoV-2 infection (9). Samples were from 1,136 cats in Germany, 331 in the United Kingdom, 333 in Italy, and 360 in Spain. Among 1,799 samples with demographic data, cats ranged from 0.1-23 years of age (median and mean age 11 years). We estimated a minimum of 300 total samples per location to enable a realistic estimation for each location. To confi rm specifi city of the assays to detect SARS-CoV-2-specifi c antibodies, we included 25 prepandemic cat serum samples and 25 serum samples from cats that tested positive for feline coronavirus/feline infectious peritonitis ( FCoV/FIP) by NovaTec VetLine (Novatec Immundiagnostica GmbH, ), a commercial antibody test, in the screening. We tested all serum samples by VNT, as previously described (10). We considered serum samples positive when titers were >20, expressed as the reciprocal of the dilution that gave >80% reduction of stained cells in the plaque reduction neutralization test (PRNT 80 ) (Appendix, EID/article/27/12/21-1252-App1.pdf). We also tested serum samples with an indirect ELISA we developed and validated inhouse. We used an ELISA previously used for detecting SARS-CoV-2 RBD antibodies in human serum (11) and replaced the anti-human IgG conjugate with an anti-cat IgG conjugate (Appendix). We evaluated performance characteristics of the cat ELISA-RBD by using Pearson correlation of the results obtained by ELISA-RBD and Gaussian distribution analyses for the VNT. We also calculated
Studies in female dogs proved the measurement of anti-Müllerian hormone (AMH) as a diagnostic too... more Studies in female dogs proved the measurement of anti-Müllerian hormone (AMH) as a diagnostic tool to distinguish ovarioectomized from intact females or to diagnose ovarian remnant syndrome. Furthermore, its usability to diagnose a granulosa cell tumour and predict litter size was also investigated in female dogs. Although serum AMH was previously shown to increase during the transition from anoestrus to pro-oestrus in dogs, changes in AMH concentration over the entire M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT clearly distinguish between intact and spayed females and that the serum AMH pattern over the oestrous cycle is similar in all bitches, but with high variation among the breeds and among and within bitches. These changes in the AMH concentration are a challenge in timing serum sample collection and interpreting AMH values in bitches. Further studies are necessary to emphasize the factors influencing the AMH concentration.
Control of luteal regression in the dog is still poorly understood. Unlike other domestic animal ... more Control of luteal regression in the dog is still poorly understood. Unlike other domestic animal species, luteolysis is not prevented by hysterectomy. Indications that PGF 2␣ may act as an endogenous luteolytic agent have been found only in pregnant animals during the prepartal decline of progesterone. Evidence from several species indicates that the immune system plays an important role in corpus luteum (Cl) function, possibly by the release of cytokines from immigrant immune cells. Hence, in the present experiment we attempted to examine the expression of cytokines in the canine Cl during the course of dioestrus (formation and regression of the Cl), using RT-PCR. Groups of 4-5 bitches were ovario-hysterectomised on days 5, 15, 25, 35, 45 and 60-80 after ovulation.
Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an ei... more Laboruntersuchungen sind integraler Teil vieler tierärztlicher Untersuchungen. Der Anspruch an eine Laboruntersuchung ist es, die zugrunde liegende Fragestellung möglichst konkret zu beantworten. Dies ist unabhängig davon, ob die Probe im praxis- bzw. klinikeigenen oder aber in einem Versandlabor untersucht wird. Die Messergebnisse sollten die physiologische bzw. pathologische Situation des Tieres zum Zeitpunkt der Probennahme möglichst genau widerspiegeln. Der Beitrag informiert darüber, was es zu beachten gibt.
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