Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis ... more Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis familiaris). It is assumed that reproductive hormones influence tumorigenesis in this species, although the precise role of the endocrine milieu and reproductive state is subject to continuing discussion. In line with this, a recent systematic review of available data on the development of mammary neoplasms revealed weak evidence for risk reduction after neutering and an effect of age at neutering. Investigation of several hormone receptors has revealed decreased expression of estrogen receptor-alpha (ERα, ESR1), progesterone (P4) receptor (PGR), prolactin (PRL) receptor (PRLR) and growth hormone receptor (GHR) associated with neoplastic differentiation of mammary tissues. In other studies, increased levels of estrogens, progesterone and prolactin were found in serum and/or tissue homogenates of dogs with malignant neoplasms. However, the association between these entities within one animal population was never previously examined. Therefore, this study investigated the association between circulating serum concentrations of estradiol-17β, progesterone and prolactin, and gene expression of ERα (ESR1), ERβ (ESR2), PGR, PRLR, PRL and GHR, with respect to reproductive state (spayed vs. intact) and cycle stage (anestrus vs. diestrus). Additionally, the expression of E-cadherin (CDH-1) was evaluated as a possible indicator of metastatic potential. For all receptors, the lowest gene expression was found in malignant tumors compared to normal tissues of affected dogs. Steroid levels were not influenced by their corresponding receptor expression in mammary neoplasms, but increased PRL levels were negatively associated with low PRLR gene expression in malignant tumors. The expression of CDH-1 was influenced by tumor malignancy and cycle stage, i.e., the highest gene expression was found in benign mammary tumors in diestrous dogs compared to normal and malignant mammary tissues of anestrous and spayed dogs. Herein, it has been confirmed that transformation towards malignant neoplasms is associated with significant reduction of gene expression of particular hormone receptors. Only PRLR in malignant tumors seems to be influenced by circulating PRL levels. In dogs, CDH-1 can be used as a prognostic factor; its expression, however, in benign tumors is influenced by cycle stage.
Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis ... more Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis familiaris). It is assumed that reproductive hormones influence tumorigenesis in this species, although the precise role of the endocrine milieu and reproductive state is subject to continuing discussion. In line with this, a recent systematic review of available data on the development of mammary neoplasms revealed weak evidence for risk reduction after neutering and an effect of age at neutering. Investigation of several hormone receptors has revealed decreased expression of estrogen receptor-alpha (ERα, ESR1), progesterone (P4) receptor (PGR), prolactin (PRL) receptor (PRLR) and growth hormone receptor (GHR) associated with neoplastic differentiation of mammary tissues. In other studies, increased levels of estrogens, progesterone and prolactin were found in serum and/or tissue homogenates of dogs with malignant neoplasms. However, the association between these entities within one animal population was never previously examined. Therefore, this study investigated the association between circulating serum concentrations of estradiol-17β, progesterone and prolactin, and gene expression of ERα (ESR1), ERβ (ESR2), PGR, PRLR, PRL and GHR, with respect to reproductive state (spayed vs. intact) and cycle stage (anestrus vs. diestrus). Additionally, the expression of E-cadherin (CDH-1) was evaluated as a possible indicator of metastatic potential. For all receptors, the lowest gene expression was found in malignant tumors compared to normal tissues of affected dogs. Steroid levels were not influenced by their corresponding receptor expression in mammary neoplasms, but increased PRL levels were negatively associated with low PRLR gene expression in malignant tumors. The expression of CDH-1 was influenced by tumor malignancy and cycle stage, i.e., the highest gene expression was found in benign mammary tumors in diestrous dogs compared to normal and malignant mammary tissues of anestrous and spayed dogs. Herein, it has been confirmed that transformation towards malignant neoplasms is associated with significant reduction of gene expression of particular hormone receptors. Only PRLR in malignant tumors seems to be influenced by circulating PRL levels. In dogs, CDH-1 can be used as a prognostic factor; its expression, however, in benign tumors is influenced by cycle stage.
The effects of alfaxalone and propofol on neonatal vitality were studied in 22 bitches and 81 pup... more The effects of alfaxalone and propofol on neonatal vitality were studied in 22 bitches and 81 puppies after their use as anesthetic induction agents for emergency cesarean section. After assessment that surgery was indicated, bitches were randomly allocated to receive alfaxalone 1 to 2 mg/kg body weight or propofol 2 to 6 mg/kg body weight for anesthetic induction. Both drugs were administered intravenously to effect to allow endotracheal intubation, and anesthesia was maintained with isoflurane in oxygen. Neonatal vitality was assessed using a modified Apgar score that took into account heart rate, respiratory effort, reflex irritability, motility, and mucous membrane color (maximum score = 10); scores were assigned at 5, 15, and 60 minutes after delivery. Neither the number of puppies delivered nor the proportion of surviving puppies up to 3 months after delivery differed between groups. Anesthetic induction drug and time of scoring were associated with the Apgar score, but delive...
Mammary tumours represent the most common neoplastic disease of the female dog, and the incidence... more Mammary tumours represent the most common neoplastic disease of the female dog, and the incidence in female dogs is much higher than in women. Whereas the influence of sexual steroids on breast cancer (BC) development in dogs has been studied, very little is known about the role of prolactin (PRL). New studies show that until recently, the importance of PRL in human BC development and progression has been highly underestimated. PRL plays a role in promoting benign as well as malignant neoplastic cell growth in BC in vitro and in vivo. Sporadic publications proposed a tumour promotor role in the dog. The goal of this review is to summarize our knowledge about PRL and human BC as well as canine mammary tumourigenesis, and propose future research in this area.
A 10-week old male Hovawart presented with acute renal failure. Based on clinical symptoms, blood... more A 10-week old male Hovawart presented with acute renal failure. Based on clinical symptoms, blood analysis results and serology, a diagnosis of leptospirosis was made. Besides being acotemic, the puppy was initially also severely hypercalcemic. The dog was treated successfully, but developed widespread cutaneous and visceral calcifications. Severe pyloric calcification resulted in functional pyloric obstruction, which was successfully treated by pyloromyotomy. All skin lesions were cured with topical therapy within a few weeks. To the authors' knowledge, this is the first report of generalized intestinal and cutaneous calcification associated with acute renal failure due to Leptospirosis.
ABSTRACT Bei lebensschwachen Welpen wie nach Dystokie oder einem Kaiserschnitt reduziert eine fac... more ABSTRACT Bei lebensschwachen Welpen wie nach Dystokie oder einem Kaiserschnitt reduziert eine fachgerechte Assistenz die Verlustrate. Die optimale Versorgung neugeborener Welpen setzt dabei die korrekte Beurteilung der Lebensfähigkeit und die Kenntnis der physiologischen Besonderheiten der Welpen voraus.
Benign prostatic hyperplasia is a primarily non-inflammatory enlargement of the prostate due to p... more Benign prostatic hyperplasia is a primarily non-inflammatory enlargement of the prostate due to proliferation of its epithelial and mesenchymal structures. These physiological alterations can be found in more than 95 % of aged intact male dogs, but common clinical symptoms as serosanguineous urethral discharge, haematuria, flattened faeces, constipation and tenesmus are only present in a few of them. In addition to surgical castration, hormonal suppression of testicular function with GnRH-depot-analogues, inhibition of the 5alpha-reductase or peripheral androgen action with anti-androgens are available today. This enables the clinician to find the optimal therapeutic strategy for each patient.
Measurements of the canine skull are of main interest in brachycephalic dogs. They are suspected ... more Measurements of the canine skull are of main interest in brachycephalic dogs. They are suspected to have diseases associated with the shortened nose, which are summarized under the term brachycephalic syndrome. The relative length of the nose has become an important feature in breeding and research, although a defi nitive correlation to the brachycephalic syndrome still has not been proven Aron und Crowe, 1985;. Classifi cations of skull types can be made by two methods. The traditional phenotypic assignment into brachycephalic, mesaticephalic and dolichocephalic is based on the assumption, that dogs of a specifi c breed have more or less uniform skull shapes. However, alterations due to breeding and differences be tween individual dogs of the same breed must lead to modifi cations. Therefore and for a more subtle classification, skull measurements were introduced (Brehm et al., 1985;, The existing indexation methods from Evans (1993) and Brehm et al. (1985) are based on cadaver studies. They classify brachycephalic dogs as having a cranial length to facial length ratio (LL-index) of > 1.60 or a skull length to skull width ratio (LW-index) of < 1.44. However, the authors also mentioned the considerable range of those indices within a breed. were the fi rst to propose a classifi cation based on radiographs of canine skulls with the craniofacial angle (CFA) as a criterion. The CFA is defi ned by a line along the base of the skull, and another line along the hard palate. The CFA of 10 dogs from 5 breeds were retrieved and it was found that the ranges clearly overlapped. The existing indices have their limitations for clinical use, either being based on cadavers (LL-index, LW-index) or not resulting in meaningful assignments of the individual skull measurement to the phenotypic appearance of the respective breed (CFA). We therefore propose a possible new skull index (S-index), which can be easily derived from radiographs of living animals and should refl ect the phenotype of each individual. Such an index has also the potential to be linked to airstream parameters and to the clinical manifestation of respiratory problems of each individual. It offers an insight to different skull shapes between dogs of the same breed. We also propose a boundary value, which should have the potential to classify between brachycephalic and non-brachycephalic skull shapes. The new S-index is an approximation to the LL-index, retrieved form cadavers by Brehm et al. (1985). The index however was taken from radiographs in dorsoventral direction ). It is calculated by the length of the facial skull divided by the length of the cerebrum. In this context the length of the facial skull was defi ned as the distance from the rostral border of the incisal bone to the rostral border of the cavum cranii. The length of the cerebrum was measured from the rostral border of the cavum cranii to the caudal outline of the occipital bone, beginning at the dorsal border of the great foramen. The S-index was compared to the LW index and the CFA on 57 dogs of different breed, sex, age and size. They were presented to the University of Zurich for planned surgical procedures (mainly neutering). The owners agreed to the procedures necessary for this study. From all dogs, radiographs of the skull in dorsoventral (hard palate parallel to the table, ) and laterolateral direction (hard palate perpendicular to the table, ) were taken. The S-and LW-index (dorsoventral views) and CFA (laterolateral views) were determined (Tab. 1). A boundary value (BV) for the S-index was evaluated which allows for a separation of the brachycephalic and the non-brachycephalic breeds by the following method. First, the dogs in the present study were classifi ed on the basis of the established separating BV for the LW-index (Brehm et al., 1985). Secondly, the BV of S-index was determined such that the highest score in coincidence of classifi cation occurred for both, the brachycephalic and non-brachycephalic breeds . In this manner, it was found that all dogs having an S-index equal or below the BV of 1.25 are considered to have a brachycephalic skull shape (Tab. 1). In parallel the respective CFA were listed.
Background: Endocrine mechanisms governing canine reproductive function remain still obscure. Pro... more Background: Endocrine mechanisms governing canine reproductive function remain still obscure. Progesterone (P4) of luteal origin is required for maintenance of pregnancy. Corpora lutea (CL) are gonadotrop-independent during the first third of dioestrus; afterwards prolactin (PRL) is the primary luteotropic factor. Interestingly, the increasing PRL levels are accompanied by decreasing P4 concentrations, thus luteal regression/luteolysis occurs in spite of an increased availability of gonadotropic support. PRL acts through its receptor (PRLr), the expression of which has not yet been thoroughly investigated at the molecular and cellular level in the dog. Methods: The expression of PRLr was assessed in CL of non-pregnant dogs during the course of dioestrus (days 5, 15, 25, 35, 45, 65 post ovulation; p.o.) as well as in CL, the utero/placental compartments (Ut/Pl) and interplacental free polar zones (interplacental sites) from pregnant dogs during the pre-implantation, post-implantation and midgestation period of pregnancy and during the normal and antigestagen-induced luteolysis. Expression of PRLr was tested by Real Time PCR, immunohistochemistry and in situ hybridization. Results: In non-pregnant CL the PRLr expression was significantly upregulated at day 15 p.o. and decreased significantly afterwards, towards the end of dioestrus. CL of pregnancy showed elevated PRLr expression until mid gestation while prepartal downregulation was observed. Interestingly, placental but not interplacental expression of PRLr was strongly time-related; a significant upregulation was observed towards mid-gestation. Within the CL PRLr was localized to the luteal cells; in the Ut/Pl it was localized to the fetal trophoblast and epithelial cells of glandular chambers. Moreover, in mid-pregnant animals treated with an antigestagen, both the luteal and placental, but not the uterine PRLr were significantly downregulated.
Assessment of gestational age and parturition date prediction is a challenging, yet common task i... more Assessment of gestational age and parturition date prediction is a challenging, yet common task in clinical management of the pregnant bitch or queen. Knowing the approximate parturition date is essential for a thorough pregnancy monitoring. Radiographic and ultrasonographic methods are suitable in bitches and queens. In the bitch, moreover, ovulation timing by means of LH or progesterone assay, determination of onset of vaginal dioestrus by means of examination of vaginal cytology, and recognition of impending parturition by monitoring prepartal progesterone levels and body temperature variation are practical methods. A combination of different methods increases the accuracy of parturition date prediction.
Objective-To evaluate a modified posterior rhinomanometric method for clinical application in dog... more Objective-To evaluate a modified posterior rhinomanometric method for clinical application in dogs. Animals-15 healthy Beagles and 8 Bulldogs (4 healthy and 4 with respiratory problems). Procedures-Rhinomanometry was performed 3 times within a 15-minute period in anesthetized dogs. Transnasal pressure (P NA ) and nasal resistance (R NA ) were determined by use of artificial airflow (adjusted for body weight) for inspiration (P NAin and R NAin , respectively) and expiration (P NAout and R NAout ). Procedures were repeated for the Beagles 7 days later. Results-For the Beagles, mean ± SD of PNAin for both days (0.162 ± 0.042 kPa) was significantly lower than P NAout (0.183 ± 0.053 kPa). Similarly, R NAin (1.47 ± 0.41 kPa/[L/s]) was significantly lower than R NAout (1.64 ± 0.46 kPa/[L/s]). Pairwise comparison of values for P NA and R NA for the 2 days revealed no significant difference. Repeatability of the method (estimated as within-day variation) for R NA was ± 0.19 kPa/(L/s), whereas variation between the days was ± 0.36 kPa/(L/s) for R NAin and ± 0.44 kPa/(L/s) for R NAout . The 4 clinically normal Bulldogs had R NA values ranging from 1.69 to 3.48 kPa/(L/s), whereas in the 4 Bulldogs with respiratory problems, R NA ranged from 9.83 to 20.27 kPa/(L/s). Conclusions and Clinical Relevance-R NA is inversely dependent on body size and nonlinearly associated with airflow. We propose that R NA in dogs should be determined for airflows standardized on the basis of body size. The P NA and R NA in Beagles can be measured with sufficient repeatability for clinical use and nasal obstructions are detectable. (Am J Vet Res 2007;68:178-184) Abbreviations
Background: Mammary tumors represent the most common neoplastic disease in female dogs. Recently,... more Background: Mammary tumors represent the most common neoplastic disease in female dogs. Recently, the promoting role of prolactin (PRL) in the development of human breast carcinoma has been shown. Possible proliferative, anti-apoptotic, migratory and angiogenic effects of PRL on human mammary cancer cells in vitro and in vivo were suggested. The effects of PRL are mediated by its receptor, and alterations in receptor expression are likely to play a role in tumor development. Currently, not much data is available about prolactin receptor (PRLR) expression in canine mammary tumors. To set the basis for investigations on the role of PRL in mammary tumorigenesis in this species, prolactin receptor expression was evaluated by semi-quantitative real time PCR and immunohistochemistry on 10 formalin-fixed, paraffin-embedded samples each of canine non-neoplastic mammary tissue, mammary adenomas and adenocarcinomas. Results: The highest PRLR expression levels were found in normal mammary tissue, while adenomas, and to an even higher degree adenocarcinomas, showed a significant decrease in prolactin receptor expression. Compared to normal tissue, PRLR mRNA was reduced 2.4 fold (p = 0.0261) in adenomas and 4.8 fold (p = 0.008) in adenocarcinomas. PRLR mRNA expression was significantly lower in malignant than in benign lesions (p = 0.0165). Immunohistochemistry demonstrated PRLR expression in all three tissue types with signals mostly limited to epithelial cells.
Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis ... more Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis familiaris). It is assumed that reproductive hormones influence tumorigenesis in this species, although the precise role of the endocrine milieu and reproductive state is subject to continuing discussion. In line with this, a recent systematic review of available data on the development of mammary neoplasms revealed weak evidence for risk reduction after neutering and an effect of age at neutering. Investigation of several hormone receptors has revealed decreased expression of estrogen receptor-alpha (ERα, ESR1), progesterone (P4) receptor (PGR), prolactin (PRL) receptor (PRLR) and growth hormone receptor (GHR) associated with neoplastic differentiation of mammary tissues. In other studies, increased levels of estrogens, progesterone and prolactin were found in serum and/or tissue homogenates of dogs with malignant neoplasms. However, the association between these entities within one animal population was never previously examined. Therefore, this study investigated the association between circulating serum concentrations of estradiol-17β, progesterone and prolactin, and gene expression of ERα (ESR1), ERβ (ESR2), PGR, PRLR, PRL and GHR, with respect to reproductive state (spayed vs. intact) and cycle stage (anestrus vs. diestrus). Additionally, the expression of E-cadherin (CDH-1) was evaluated as a possible indicator of metastatic potential. For all receptors, the lowest gene expression was found in malignant tumors compared to normal tissues of affected dogs. Steroid levels were not influenced by their corresponding receptor expression in mammary neoplasms, but increased PRL levels were negatively associated with low PRLR gene expression in malignant tumors. The expression of CDH-1 was influenced by tumor malignancy and cycle stage, i.e., the highest gene expression was found in benign mammary tumors in diestrous dogs compared to normal and malignant mammary tissues of anestrous and spayed dogs. Herein, it has been confirmed that transformation towards malignant neoplasms is associated with significant reduction of gene expression of particular hormone receptors. Only PRLR in malignant tumors seems to be influenced by circulating PRL levels. In dogs, CDH-1 can be used as a prognostic factor; its expression, however, in benign tumors is influenced by cycle stage.
Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis ... more Neoplasms of the mammary gland are among the most common diseases in female domestic dogs (Canis familiaris). It is assumed that reproductive hormones influence tumorigenesis in this species, although the precise role of the endocrine milieu and reproductive state is subject to continuing discussion. In line with this, a recent systematic review of available data on the development of mammary neoplasms revealed weak evidence for risk reduction after neutering and an effect of age at neutering. Investigation of several hormone receptors has revealed decreased expression of estrogen receptor-alpha (ERα, ESR1), progesterone (P4) receptor (PGR), prolactin (PRL) receptor (PRLR) and growth hormone receptor (GHR) associated with neoplastic differentiation of mammary tissues. In other studies, increased levels of estrogens, progesterone and prolactin were found in serum and/or tissue homogenates of dogs with malignant neoplasms. However, the association between these entities within one animal population was never previously examined. Therefore, this study investigated the association between circulating serum concentrations of estradiol-17β, progesterone and prolactin, and gene expression of ERα (ESR1), ERβ (ESR2), PGR, PRLR, PRL and GHR, with respect to reproductive state (spayed vs. intact) and cycle stage (anestrus vs. diestrus). Additionally, the expression of E-cadherin (CDH-1) was evaluated as a possible indicator of metastatic potential. For all receptors, the lowest gene expression was found in malignant tumors compared to normal tissues of affected dogs. Steroid levels were not influenced by their corresponding receptor expression in mammary neoplasms, but increased PRL levels were negatively associated with low PRLR gene expression in malignant tumors. The expression of CDH-1 was influenced by tumor malignancy and cycle stage, i.e., the highest gene expression was found in benign mammary tumors in diestrous dogs compared to normal and malignant mammary tissues of anestrous and spayed dogs. Herein, it has been confirmed that transformation towards malignant neoplasms is associated with significant reduction of gene expression of particular hormone receptors. Only PRLR in malignant tumors seems to be influenced by circulating PRL levels. In dogs, CDH-1 can be used as a prognostic factor; its expression, however, in benign tumors is influenced by cycle stage.
The effects of alfaxalone and propofol on neonatal vitality were studied in 22 bitches and 81 pup... more The effects of alfaxalone and propofol on neonatal vitality were studied in 22 bitches and 81 puppies after their use as anesthetic induction agents for emergency cesarean section. After assessment that surgery was indicated, bitches were randomly allocated to receive alfaxalone 1 to 2 mg/kg body weight or propofol 2 to 6 mg/kg body weight for anesthetic induction. Both drugs were administered intravenously to effect to allow endotracheal intubation, and anesthesia was maintained with isoflurane in oxygen. Neonatal vitality was assessed using a modified Apgar score that took into account heart rate, respiratory effort, reflex irritability, motility, and mucous membrane color (maximum score = 10); scores were assigned at 5, 15, and 60 minutes after delivery. Neither the number of puppies delivered nor the proportion of surviving puppies up to 3 months after delivery differed between groups. Anesthetic induction drug and time of scoring were associated with the Apgar score, but delive...
Mammary tumours represent the most common neoplastic disease of the female dog, and the incidence... more Mammary tumours represent the most common neoplastic disease of the female dog, and the incidence in female dogs is much higher than in women. Whereas the influence of sexual steroids on breast cancer (BC) development in dogs has been studied, very little is known about the role of prolactin (PRL). New studies show that until recently, the importance of PRL in human BC development and progression has been highly underestimated. PRL plays a role in promoting benign as well as malignant neoplastic cell growth in BC in vitro and in vivo. Sporadic publications proposed a tumour promotor role in the dog. The goal of this review is to summarize our knowledge about PRL and human BC as well as canine mammary tumourigenesis, and propose future research in this area.
A 10-week old male Hovawart presented with acute renal failure. Based on clinical symptoms, blood... more A 10-week old male Hovawart presented with acute renal failure. Based on clinical symptoms, blood analysis results and serology, a diagnosis of leptospirosis was made. Besides being acotemic, the puppy was initially also severely hypercalcemic. The dog was treated successfully, but developed widespread cutaneous and visceral calcifications. Severe pyloric calcification resulted in functional pyloric obstruction, which was successfully treated by pyloromyotomy. All skin lesions were cured with topical therapy within a few weeks. To the authors' knowledge, this is the first report of generalized intestinal and cutaneous calcification associated with acute renal failure due to Leptospirosis.
ABSTRACT Bei lebensschwachen Welpen wie nach Dystokie oder einem Kaiserschnitt reduziert eine fac... more ABSTRACT Bei lebensschwachen Welpen wie nach Dystokie oder einem Kaiserschnitt reduziert eine fachgerechte Assistenz die Verlustrate. Die optimale Versorgung neugeborener Welpen setzt dabei die korrekte Beurteilung der Lebensfähigkeit und die Kenntnis der physiologischen Besonderheiten der Welpen voraus.
Benign prostatic hyperplasia is a primarily non-inflammatory enlargement of the prostate due to p... more Benign prostatic hyperplasia is a primarily non-inflammatory enlargement of the prostate due to proliferation of its epithelial and mesenchymal structures. These physiological alterations can be found in more than 95 % of aged intact male dogs, but common clinical symptoms as serosanguineous urethral discharge, haematuria, flattened faeces, constipation and tenesmus are only present in a few of them. In addition to surgical castration, hormonal suppression of testicular function with GnRH-depot-analogues, inhibition of the 5alpha-reductase or peripheral androgen action with anti-androgens are available today. This enables the clinician to find the optimal therapeutic strategy for each patient.
Measurements of the canine skull are of main interest in brachycephalic dogs. They are suspected ... more Measurements of the canine skull are of main interest in brachycephalic dogs. They are suspected to have diseases associated with the shortened nose, which are summarized under the term brachycephalic syndrome. The relative length of the nose has become an important feature in breeding and research, although a defi nitive correlation to the brachycephalic syndrome still has not been proven Aron und Crowe, 1985;. Classifi cations of skull types can be made by two methods. The traditional phenotypic assignment into brachycephalic, mesaticephalic and dolichocephalic is based on the assumption, that dogs of a specifi c breed have more or less uniform skull shapes. However, alterations due to breeding and differences be tween individual dogs of the same breed must lead to modifi cations. Therefore and for a more subtle classification, skull measurements were introduced (Brehm et al., 1985;, The existing indexation methods from Evans (1993) and Brehm et al. (1985) are based on cadaver studies. They classify brachycephalic dogs as having a cranial length to facial length ratio (LL-index) of > 1.60 or a skull length to skull width ratio (LW-index) of < 1.44. However, the authors also mentioned the considerable range of those indices within a breed. were the fi rst to propose a classifi cation based on radiographs of canine skulls with the craniofacial angle (CFA) as a criterion. The CFA is defi ned by a line along the base of the skull, and another line along the hard palate. The CFA of 10 dogs from 5 breeds were retrieved and it was found that the ranges clearly overlapped. The existing indices have their limitations for clinical use, either being based on cadavers (LL-index, LW-index) or not resulting in meaningful assignments of the individual skull measurement to the phenotypic appearance of the respective breed (CFA). We therefore propose a possible new skull index (S-index), which can be easily derived from radiographs of living animals and should refl ect the phenotype of each individual. Such an index has also the potential to be linked to airstream parameters and to the clinical manifestation of respiratory problems of each individual. It offers an insight to different skull shapes between dogs of the same breed. We also propose a boundary value, which should have the potential to classify between brachycephalic and non-brachycephalic skull shapes. The new S-index is an approximation to the LL-index, retrieved form cadavers by Brehm et al. (1985). The index however was taken from radiographs in dorsoventral direction ). It is calculated by the length of the facial skull divided by the length of the cerebrum. In this context the length of the facial skull was defi ned as the distance from the rostral border of the incisal bone to the rostral border of the cavum cranii. The length of the cerebrum was measured from the rostral border of the cavum cranii to the caudal outline of the occipital bone, beginning at the dorsal border of the great foramen. The S-index was compared to the LW index and the CFA on 57 dogs of different breed, sex, age and size. They were presented to the University of Zurich for planned surgical procedures (mainly neutering). The owners agreed to the procedures necessary for this study. From all dogs, radiographs of the skull in dorsoventral (hard palate parallel to the table, ) and laterolateral direction (hard palate perpendicular to the table, ) were taken. The S-and LW-index (dorsoventral views) and CFA (laterolateral views) were determined (Tab. 1). A boundary value (BV) for the S-index was evaluated which allows for a separation of the brachycephalic and the non-brachycephalic breeds by the following method. First, the dogs in the present study were classifi ed on the basis of the established separating BV for the LW-index (Brehm et al., 1985). Secondly, the BV of S-index was determined such that the highest score in coincidence of classifi cation occurred for both, the brachycephalic and non-brachycephalic breeds . In this manner, it was found that all dogs having an S-index equal or below the BV of 1.25 are considered to have a brachycephalic skull shape (Tab. 1). In parallel the respective CFA were listed.
Background: Endocrine mechanisms governing canine reproductive function remain still obscure. Pro... more Background: Endocrine mechanisms governing canine reproductive function remain still obscure. Progesterone (P4) of luteal origin is required for maintenance of pregnancy. Corpora lutea (CL) are gonadotrop-independent during the first third of dioestrus; afterwards prolactin (PRL) is the primary luteotropic factor. Interestingly, the increasing PRL levels are accompanied by decreasing P4 concentrations, thus luteal regression/luteolysis occurs in spite of an increased availability of gonadotropic support. PRL acts through its receptor (PRLr), the expression of which has not yet been thoroughly investigated at the molecular and cellular level in the dog. Methods: The expression of PRLr was assessed in CL of non-pregnant dogs during the course of dioestrus (days 5, 15, 25, 35, 45, 65 post ovulation; p.o.) as well as in CL, the utero/placental compartments (Ut/Pl) and interplacental free polar zones (interplacental sites) from pregnant dogs during the pre-implantation, post-implantation and midgestation period of pregnancy and during the normal and antigestagen-induced luteolysis. Expression of PRLr was tested by Real Time PCR, immunohistochemistry and in situ hybridization. Results: In non-pregnant CL the PRLr expression was significantly upregulated at day 15 p.o. and decreased significantly afterwards, towards the end of dioestrus. CL of pregnancy showed elevated PRLr expression until mid gestation while prepartal downregulation was observed. Interestingly, placental but not interplacental expression of PRLr was strongly time-related; a significant upregulation was observed towards mid-gestation. Within the CL PRLr was localized to the luteal cells; in the Ut/Pl it was localized to the fetal trophoblast and epithelial cells of glandular chambers. Moreover, in mid-pregnant animals treated with an antigestagen, both the luteal and placental, but not the uterine PRLr were significantly downregulated.
Assessment of gestational age and parturition date prediction is a challenging, yet common task i... more Assessment of gestational age and parturition date prediction is a challenging, yet common task in clinical management of the pregnant bitch or queen. Knowing the approximate parturition date is essential for a thorough pregnancy monitoring. Radiographic and ultrasonographic methods are suitable in bitches and queens. In the bitch, moreover, ovulation timing by means of LH or progesterone assay, determination of onset of vaginal dioestrus by means of examination of vaginal cytology, and recognition of impending parturition by monitoring prepartal progesterone levels and body temperature variation are practical methods. A combination of different methods increases the accuracy of parturition date prediction.
Objective-To evaluate a modified posterior rhinomanometric method for clinical application in dog... more Objective-To evaluate a modified posterior rhinomanometric method for clinical application in dogs. Animals-15 healthy Beagles and 8 Bulldogs (4 healthy and 4 with respiratory problems). Procedures-Rhinomanometry was performed 3 times within a 15-minute period in anesthetized dogs. Transnasal pressure (P NA ) and nasal resistance (R NA ) were determined by use of artificial airflow (adjusted for body weight) for inspiration (P NAin and R NAin , respectively) and expiration (P NAout and R NAout ). Procedures were repeated for the Beagles 7 days later. Results-For the Beagles, mean ± SD of PNAin for both days (0.162 ± 0.042 kPa) was significantly lower than P NAout (0.183 ± 0.053 kPa). Similarly, R NAin (1.47 ± 0.41 kPa/[L/s]) was significantly lower than R NAout (1.64 ± 0.46 kPa/[L/s]). Pairwise comparison of values for P NA and R NA for the 2 days revealed no significant difference. Repeatability of the method (estimated as within-day variation) for R NA was ± 0.19 kPa/(L/s), whereas variation between the days was ± 0.36 kPa/(L/s) for R NAin and ± 0.44 kPa/(L/s) for R NAout . The 4 clinically normal Bulldogs had R NA values ranging from 1.69 to 3.48 kPa/(L/s), whereas in the 4 Bulldogs with respiratory problems, R NA ranged from 9.83 to 20.27 kPa/(L/s). Conclusions and Clinical Relevance-R NA is inversely dependent on body size and nonlinearly associated with airflow. We propose that R NA in dogs should be determined for airflows standardized on the basis of body size. The P NA and R NA in Beagles can be measured with sufficient repeatability for clinical use and nasal obstructions are detectable. (Am J Vet Res 2007;68:178-184) Abbreviations
Background: Mammary tumors represent the most common neoplastic disease in female dogs. Recently,... more Background: Mammary tumors represent the most common neoplastic disease in female dogs. Recently, the promoting role of prolactin (PRL) in the development of human breast carcinoma has been shown. Possible proliferative, anti-apoptotic, migratory and angiogenic effects of PRL on human mammary cancer cells in vitro and in vivo were suggested. The effects of PRL are mediated by its receptor, and alterations in receptor expression are likely to play a role in tumor development. Currently, not much data is available about prolactin receptor (PRLR) expression in canine mammary tumors. To set the basis for investigations on the role of PRL in mammary tumorigenesis in this species, prolactin receptor expression was evaluated by semi-quantitative real time PCR and immunohistochemistry on 10 formalin-fixed, paraffin-embedded samples each of canine non-neoplastic mammary tissue, mammary adenomas and adenocarcinomas. Results: The highest PRLR expression levels were found in normal mammary tissue, while adenomas, and to an even higher degree adenocarcinomas, showed a significant decrease in prolactin receptor expression. Compared to normal tissue, PRLR mRNA was reduced 2.4 fold (p = 0.0261) in adenomas and 4.8 fold (p = 0.008) in adenocarcinomas. PRLR mRNA expression was significantly lower in malignant than in benign lesions (p = 0.0165). Immunohistochemistry demonstrated PRLR expression in all three tissue types with signals mostly limited to epithelial cells.
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Papers by Erika Michel