Biomedical subjects

K Failing

Publications and source records attributed to K Failing.

At least 19 recordsLinked to original sources

PubMed2006

Serotonin-containing cells in the gastrointestinal tract of newborn foals and adult horses.

Serotonin (5-hydroxytryptamine, 5-HT), a regulatory amine of mucosal enterochromaffin cells plays an important role in the control of gastrointestinal smooth muscle contraction and epithelial secretion. Serotonin has also been associated with gastric ulcers, diarrhoea and abdominal pain. In spite of the high incidence of these gastrointestinal disorders in newborn foals and adult horses, no data are available regarding 5-HT immunoreactive cells (i.c.) in the gastrointestinal tract (GIT) of foals, and for adult horses, data are incomplete and contradictory. In this study, the distribution and relative frequency of 5-HT i.c. in the GIT of newborn foals and adult horses were determined immunohistochemically. In foals as in adults, a relatively large number of 5-HT i.c. were detected in all portions of the GIT. In foals, a significantly higher amount of cells was found in the pyloric region and margo plicatus of the stomach, as well as in the caecum and colon ascendens compared with adults. Our results provided rationale for further research concerning the role of 5-HT i.c. during the milk diet or in the regulation of gastrointestinal growth/cell proliferation, and in the pathogenesis of gastric ulcers, especially in newborn foals.

Animals↗

PubMed2006

Determination of the inhibitory concentration 50% (IC50) of four selected drugs (chlortetracycline, doxycycline, enrofloxacin and difloxacin) that reduce in vitro the multiplication of Chlamydophila psittaci.

A total of 18 chlamydial isolates from various psittacine birds, one isolate from a domestic pigeon and one isolate from a Pekin duck were isolated in continuous Buffalo Green Monkey (BGM) kidney cell cultures. All 20 isolates were identified by nested multiplex polymerase chain reaction as Chlamydophila psittaci. These isolates were multiplied to high titres and subsequently tested for in vitro sensitivity against two tetracyclines (chlortetracycline and doxycycline) and two quinolones (enrofloxacin and difloxacin) at concentrations of 0.0, 0.25, 0.50, 1.00, and 10.00 microg/ml. Replication of chlamydia in BGM cell cultures is assayed on the basis of formation of intracytoplasmic inclusions that are visualized by Giménez staining. All isolates, although to variable degrees, are sensitive to all four drugs. The number of chlamydial inclusions decreases gradually over a broad range of increasing concentrations of the drugs. The variation in the number of inclusions between isolates is remarkably high for chlortetracycline less for doxycycline and minimal for both fluoroquinolones, the enrofloxacin and difloxacin. The decline in numbers of inclusions is highly dose-dependend and the observed reduction stretches over a wide range of drug dilutions. Therefore, it is proposed to calculate drug sensitivity values in terms of inhibitory concentration 50%, (IC5). Its calculation includes all tested drug dilutions instead of the hitherto more common minimal inhibitory concentration, MIC, which is based on results of serial dilution tests for cell-free growing bacteria. Using a logistic regression model for the calculation of the inhibitory concentration 50% of all 20 chlamydial isolates, the IC50 is 0.807 microg/ml for tetracycline, 0.497 microg/ml for doxycycline, 0.180 microg/ml for enrofloxacin and 0.168 microg/ml for difloxacin. Complete prevention of inclusion formation was already seen for enrofloxacin at a concentration of 1.0 microg/ml in 12 out of 20 and for difloxacin in 5 out of 20 isolates whereas more than 10 microg/mI chlortetracycline is needed in 15 out of 20 isolates and for doxycycline 9 out of 20 isolates yielded inclusions at 10 microg/ml.

Animals↗

PubMed2005

Estrogen receptor beta (ERbeta) is expressed differently from ERalpha in bovine placentomes.

The functions of placental estrogens in cattle are still poorly understood. In order to investigate a putative role as local regulators of placental growth, differentiation and functions via estrogen receptor beta (ERbeta), the expression of this ER isoform was determined in bovine placentomes obtained from cows at midgestation (days 110-150; n=7), late gestation (days 180-280; n=9), from prepartal cows (sampling immediately after the prepartal decline in maternal progesterone blood levels became obvious; n=3) and from cows at normal term (n=5) on the protein and mRNA level. By means of immunohistochemistry using a monoclonal antibody against human ERbeta (clone PPG5/10), nuclear signals were found in numerous cell types of the fetal (cotyledon) and maternal (caruncle) component of the placentomes with highest intensities in mature trophoblast giant cells (TGC), fetal and maternal vascular cells and caruncular stromal cells, in which the percentage of positive cells increased from 58.9+/-2.3 and 59.1+/-3.3 at mid- and late gestation to 65.1+/-4.9 and 69.4+/-4.2 in prepartal and parturient cows, resp. (p<0.0001). Clear staining of uninucleated trophoblast cells was only observed in prepartal and parturient animals. Conventional RT-PCR confirmed ERbeta expression in caruncles and cotyledons at all phases under investigation. With semi-quantitative real-time RT-PCR higher levels of ERbeta-specific mRNA were measured in cotyledons compared to caruncles (p<0.01). The results show that in contrast to ERalpha, which is only expressed in the caruncle, ERbeta is also extensively expressed in the cotyledon and suggest a role of ERbeta primarily in TGC differentiation and placental angiogenesis and/or vascular functions.

Animals↗

PubMed2005

Influence of partus induction on the pH value in the blood of newborn piglets.

Partus induction is an important integrative component of reproduction management in the swine industry. In this context, the question is to what extent the application of uterotonic substances may influence the vitality of piglets. The blood pH value is used as a laboratory objective diagnostic parameter of neonatal acidosis. This parameter of the acid-base balance was examined in piglets born spontaneously at the 115th to 116th day of gestation (group 1, n = 57) and after two different partus induction protocols starting at the 114th day of gestation (group 2: combination of 175 microg of cloprostenol and 20 IU of oxytocin, n = 55; group 3: 175 microg of cloprostenol and 35 microg of carbetocin, n = 56). Initial blood samples were taken from each piglet at birth and 2 h later. The results show that the different protocols have no negative influence on the initial pH value and the compensation of neonatal acidosis until the second hour post-natum.

Acid-Base Equilibrium↗

PubMed2004

Cross-sectional survey in pig breeding farms in Hesse, Germany: seroprevalence and risk factors of infections with Toxoplasma gondii, Sarcocystis spp. and Neospora caninum in sows.

A cross-sectional survey was performed to estimate the prevalences of antibodies to Toxoplasma gondii (ELISA, IFAT), Sarcocystis spp. (ELISA, using S. miescheriana as antigen) and Neospora caninum (ELISA, immunoblotting) in sows from breeding farms in southern Hesse, Germany. A total of 2041 plasma samples of sows from 94 randomly selected farms was examined. Data on farm profiles, husbandry management and sows were collected by a questionnaire and exploratively analysed. For T. gondii the ELISA results agreed well with the results obtained by IFAT (kappa=0.71). Antibodies to T. gondii were detected by ELISA in 19% of the sows. Sixty-nine percent of the farms had at least one seropositive sow, and a within-farm seroprevalence of >or=50% was observed in 14% of all farms. The prevalence of anti-T. gondii antibodies was positively correlated with the age of sows. The within-herd seroprevalence was significantly higher in farms with reproductive disorders than in those without such problems. On the farm level, the farm type 'piglet production' (versus 'pedigree breeding' or 'farrow-to-finish') was the only risk factor associated with the presence of T. gondii-seropositive sows. Antibodies to Sarcocystis spp. were found in 29% of the sows. Seventy-two percent of the farms harboured at least one seropositive sow, and a within-farm seroprevalence of >or=50% was detected in 23% of all farms. The seroprevalence increased significantly with the age of sows. On the farm level, only the farm type 'piglet production' (versus 'pedigree breeding') and the replacement of sows by purchasing (versus raising on the own farm) were identified as risk factors for seropositivity. Antibodies to N. caninum were detected in one sow using both the screening ELISA and the confirmatory immunoblotting technique. This may indicate the first natural N. caninum infection in pigs.

Age Factors↗

PubMed2004

Reduced constitutive cytokine transcription in isolated monocytes of clinically healthy cats, infected with an FIV strain of low pathogenicity.

Twenty-five barrier-maintained cats had been experimentally infected for 9.5 months with an FIV strain of low pathogenicity, FIV Zurich 2. Animals were clinically healthy and did not exhibit any haematological changes. FIV proviral DNA was demonstrated in peripheral blood lymphocytes of all cats and in monocytes of most animals, identifying FIV Zurich 2 as a both lympho- and monocytotropic strain. Monocytes were isolated from FIV-infected cats as well as from age-matched uninfected control cats, short-term cultured and examined for cytokine (IL-1beta, IL-6, IL-10, IL-12 p40 and TNF-alpha) transcription by real-time PCR. Constitutive transcription of cytokines in monocytes from FIV-infected cats was restricted to IL-1beta and, in the majority of samples, TNF-alpha. For all cytokines, transcription levels were significantly lower in FIV-infected cats than in control cats. Transcription was often least intense in those samples where FIV infection of the monocyte fraction was not demonstrated. Results show that infection of cats with an FIV strain of low pathogenicity was associated with depression of constitutive cytokine transcription in monocytes even if clinical and haematological changes were not observed.

Animals↗

PubMed2004

Studies on the time course of the effects of the probiotic yeast Saccharomyces boulardii on electrolyte transport in pig jejunum.

Orally administered Saccharomyces boulardii (synonym Saccharomyces cerevisiae Hansen CBS 5926) has already been shown to affect relevant functions of the mucosa in pig jejunum such as lowering the secretory response to theophylline or stimulating sodium/glucose cotransport, but knowledge of time-dependent relationship is minimal. In this study we examined the effects of S. boulardii on sodium (Na+) and chloride (Cl-) transport in pig jejunum under nonstimulated (basal) and stimulated (secretory) conditions. For this purpose the conventional Ussing chamber method was used for measuring electrical parameters (short circuit currents, Isc; tissue conductances, G(T)) and electrolyte transport of isolated intact jejunal epithelia in the absence and presence of the secretagogue theophylline (10 mM, serosal side). Time profiles of the mucosa response were assessed by treating animals perorally with S. boulardii for 0 (control), 3, 8, and 16 days. Intestinal tissues were obtained from growing pigs in the weight range between 25 and 40 kg. All animals were fed twice daily and received 1.0-1.6 kg/day of a standard diet avoiding probiotics as food additives. After a 9- to 10-day adaptation period the diets for treated animals were supplemented with approximately 1.8 x 10(7) colony forming units (CFU)/g feed of the probiotic. Whereas basal tissue conductances were not affected by treatment duration, basal Isc values decreased significantly during 8 days of treatment, by 26%, indicating a lower electrogenic net ion transport, which, however, was reconstituted after 16 days. This effect could be explained by almost the same reduction of basal Jms of Na+ during 8 days of treatment, whereas respective flux rates in the opposite direction remained stable. Under basal conditions unidirectional and net flux rates of Cl- were not affected by S. boulardii. Induction of secretory conditions by theophylline revealed pronounced increases in net Cl- secretion but this effect was more than 60% lower after 8-day S. boulardii application, and this was reflected by a respectively lower Isc stimulation. Interestingly, this inhibitory effect on the secretory response could no longer be observed in the 16-day group. And this was reflected by a respectively lower Isc stimulation. A similar effect could be observed regarding net Na+ flux rates. Residual fluxes were affected neither by S. boulardii nor by theophylline, therefore, Isc values can be explained completely by respective Na+ and Cl- fluxes. In conclusion, S. boulardii has specific duration-dependent effects on the secretory response of the pig jejunal mucosa which developed during 8-day treatment but disappeared during further application. Thus, this study supports the concept that probiotics may exert beneficial effects in the gastrointestinal tract.

Animals↗

PubMed2004

Prevalence, risk factors and economic importance of infestations with Sarcoptes scabiei and Haematopinus suis in sows of pig breeding farms in Hesse, Germany.

A cross-sectional survey was performed in 110 randomly selected pig-breeding farms of southern Hesse, Germany to estimate the prevalence of ectoparasite infestations and to find possible risk factors. Ear scrapings of, if available, 10 sows per farm were examined for Sarcoptes scabiei var. suis (De Geer) (Acaridida: Sarcoptidae) by the potassium hydroxide digestion method, and a total of 2754 sows was inspected for skin lesions and infestations with Haematopinus suis (L.) (Anoplurida: Haematopinidae). Data on farm profiles and sows were collected by a questionnaire. In total, 19.1% and 2.5% of the sows were found to be infested with S. scabiei or H. suis, respectively. The percentage of mite or louse infestation was significantly higher in sows showing pruritus than in those without skin lesions. Both ectoparasite infestations were related neither to the age of sows nor their reproduction status, nor to the time interval to last ectoparasite treatment. Using farms as the unit of analysis, the estimated prevalence of mange mite and louse infestations was 45.4% and 14.5%, respectively. There was no significant association between the presence of S. scabiei and H. suis in the farms. Risk factors for S. scabiei infestation were mixed housing of dry and nursing sows in the same unit (vs. separate housing) and straw bedding (vs. strawless). For louse infestation, only mechanical cleaning of stable units (vs. additional use of disinfection methods) and pasturing of gilts and dry sows were identified as risk factors. The economic loss by S. scabiei infestation in the study population was assessed at euro 4200 per affected farm and year on average.

Animal Husbandry↗

PubMed2004

Vaginal and cervical dilatation intrapartum is associated with eosinophilic infiltration in the cow but not in the sheep.

During parturition maximal dilatation of the vagina and cervix is necessary for expulsion of the neonate. The aim of the present study was to characterize the cell infiltration of the vagina and cervix that is associated with this event in cows and sheep. For this purpose, vaginal and cervical tissue were removed from four pluriparous cows and four sheep immediately after delivery of the neonate by biopsy under visual control (group 1), and the eosinophilic granulocytes were stained selectively. Four cows that were in interoestrus were used for control (group 2). In a third group of cows (n=10), blood samples were taken to determine the concentration of eosinophilic granulocytes from the fifth day antepartum up to the sixth day postpartum (group 3). A high degree of infiltration with eosinophilic granulocytes was detected in the bovine vagina and cervix intrapartum but not during interoestrus and in the ovine tissue intrapartum (p <0.001). In the bovine tissue, the cell density was higher in the vagina than in the cervix (p <0.05). The intrapartal tissue infiltration was associated with a short-term blood eosinopenia. In conclusion, this investigation demonstrates eosinophilic infiltration in the bovine vagina and cervix intrapartum, which differs from the situation in sheep. We suggest that this difference can be explained by the fact that cows deliver at high oestrogen and low progesterone values, but sheep show relatively high intrapartal P4 levels, which might suppress tissue infiltration with eosinophilic granulocytes.

Animals↗

PubMed2004

[The logistic regression model including interactions between the factor variables demonstrated for the detection of E. coli O157.H7 in artificially contaminated minced beef].

Logistic regression is a powerful tool to analyse data sets with a dichotomous response variable. However, in most situations it is used as a model without interactions between the factor variables. This is done either by presumption or to avoid difficulties in the interpretation of the statistical results. In this article first the model of simple logistic regression without interactions is introduced followed by the expanded model with pairwise interactions between the factors. The application of both models is demonstrated at the present data set concerning the detection of E. coli O157.H7 in artificially contaminated minced beef. The influencing variables are the factors enrichment time, inoculation density, enrichment broth, subculturing medium, and state of samples (fresh vs. deep frozen). The statistical reanalysis displayed strongly differing results emphasizing the importance of interactions in logistic regression models. In particular, the odds ratio for E. coli detection dependant from the enrichment time (24 h vs. 6 h) (OR = 0.41) was strongly overestimated without simultaneous attention of the E. coli inoculation density (OR approximately equal to 0.2 to 0.02). In this context the possible interpretation of the interaction is discussed.

Animals↗

PubMed2004

Husbandry management, worm control practices and gastro-intestinal parasite infections of sows in pig-breeding farms in Münsterland, Germany.

A cross-sectional survey was performed on 144 farms randomly selected from 3 breeding organisations in Münsterland, Germany, to obtain representative data on husbandry management, worm control practices and their possible associations with gastro-intestinal parasite infections in sows. Straw bedding was provided in the majority of gestation units; lactating sows were frequently kept strawless. Pasturing of gilts and non-lactating sows were performed in 37% of the farms. Sows were treated with anthelmintics (mainly benzimidazoles, ivermectin or levamisole) in 98% of the farms. The proportions of farmers performing the 'targeted' (mainly prefarrowing) or 'non-targeted' treatment strategy (treatment of all animals several times per year) were similar. Piglets were anthelmintically dosed in only 19% of the farms. Patent infections of sows with Oesophagostomum spp., Ascaris suum, Trichuris suis and Eimeria spp. were detected in 79%, 7%, 8% and 29% of all the farms, respectively. Hyostrongylus rubidus infections were only found in farms with pasturing. The within-farm prevalences of both the strongylid and Eimeria infections were negatively correlated with the herd size but positively with the weaning age. Risk factors for strongylid infections were straw bedding in pens and pasturing. Pasturing was a risk factor for Eimeria infections too. There was a positive association between the time interval to last deworming of sows and strongylid egg counts. However, neither the treatment strategy nor the anthelmintic class used was associated with nematode infections. No relations were found between different cleaning methods in stables and endoparasite infections.

Animal Husbandry↗

PubMed2003

Analysis of codon usage in beta-tubulin sequences of helminths.

Codon usage bias has been shown to be correlated with gene expression levels in many organisms, including the nematode Caenorhabditis elegans. Here, the codon usage (cu) characteristics for a set of currently available beta-tubulin coding sequences of helminths were assessed by calculating several indices, including the effective codon number (Nc), the intrinsic codon deviation index (ICDI), the P2 value and the mutational response index (MRI). The P2 value gives a measure of translational pressure, which has been shown to be correlated to high gene expression levels in some organisms, but it has not yet been analysed in that respect in helminths. For all but two of the C. elegans beta-tubulin coding sequences investigated, the P2 value was the only index that indicated the presence of codon usage bias. Therefore, we propose that in general the helminth beta-tubulin sequences investigated here are not expressed at high levels. Furthermore, we calculated the correlation coefficients for the cu patterns of the helminth beta-tubulin sequences compared with those of highly expressed genes in organisms such as Escherichia coli and C. elegans. It was found that beta-tubulin cu patterns for all sequences of members of the Strongylida were significantly correlated to those for highly expressed C. elegans genes. This approach provides a new measure for comparing the adaptation of cu of a particular coding sequence with that of highly expressed genes in possible expression systems.Finally, using the cu patterns of the sequences studied, a phylogenetic tree was constructed. The topology of this tree was very much in concordance with that of a phylogeny based on small subunit ribosomal DNA sequence alignments.

Animals↗

PubMed2003

Influence of different tumour types on natural cytotoxicity (NK cell activity) and mitogen-induced lymphocyte proliferation in isolated blood lymphocytes from 110 dogs with tumours.

The cell-mediated immune response of blood lymphocytes from 110 untreated dogs with different tumours was evaluated. The influence of different tumour types on the cellular immune system was examined by assessing the percentage of isolated large granular lymphocytes (LGL), in vitro natural cytotoxicity and mitogen-induced lymphocyte proliferation. Although the overall natural cytotoxicity of dogs with different tumours was decreased, the overall difference from control values was not statistically significant. However, mitogen-induced lymphocyte proliferation was significantly depressed in dogs with tumours in comparison with the controls. Dogs with mammary carcinomas showed significantly lower natural cytotoxicity than controls and dogs with myeloid neoplasms showed significantly lower mitogen-induced lymphocyte proliferation. Abnormalities exist not only in natural cytotoxicity but also in mitogen-induced lymphocyte proliferation. For the dog, this is the first study to assess the influence of different tumours using a combined evaluation of natural cytotoxicity and mitogen-induced lymphocyte proliferation in such a large number of animals.

Animals↗

PubMed2003

Analysis of the beta-tubulin codon 200 genotype distribution in a benzimidazole-susceptible and -resistant cyathostome population.

To study the prevalence of the polymorphism in position 200 of the beta-tubulin gene in the mechanism of benzimidazole (BZ) resistance in cyathostomes of horses, an allele-specific PCR was used to detect the genotype of individuals of BZ-susceptible and BZ-resistant populations. The molecular analysis of 100 adults recovered from an anthelmintic-naïve horse revealed 80% homozygous TTC/TTC individuals, 17% heterozygous TTC/TAC and 3% homozygous TAC/TAC. A naturally infected horse was treated with increasing fenbendazole (FBZ) dosages to select a BZ-resistant population of cyathostomes. The PCR based analysis of 3rd-stage larvae (L3) during the experiment revealed a decrease of the homozygous TTC/TTC genotype and an increase in heterozygous TTC/TAC and homozygous TAC/TAC individuals. After treatment 42.3% of the adults (n=104) were homozygous TTC/TTC, 55.8% were heterozygous TTC/TAC and only 1.9% showed the homozygous genotype TAC/TAC. The results of the molecular analysis lead to the proposal that polymorphism within codon 200 is not the only reason for the development of BZ resistance in small strongyles.

Alleles↗

PubMed2003

Reference values of electrolyte plasma concentrations in healthy piglets during the first 48 hours of life.

The aim of this study was to analyse the plasma concentrations of sodium (Na), magnesium (Mg), calcium (Ca), inorganic phosphate (P) and potassium (K) in mature, healthy suckling pigs during the first 2 days of life in order to obtain more detailed information about this aspect of the neonatal adaptation period. Blood samples were taken from 120 suckling piglets (30 min after birth, and then at 6, 24 and 48 h post-natum). The control group consisted of 60 piglets at the ages of 1 and 2 weeks. All electrolyte concentrations showed a significant age influence (P < 0.001). Thirty minutes post-partum a significant correlation between body temperature (T) and both Mg (P < 0.05; b = -0.13) and Ca (P < 0.05, b = -0.09) could be shown. In the sixth hour of life, there was a significant dependency between Ca (P < 0.05, b = 0.48) and body mass, whereas a relationship to sex could be established for P (P < 0.05). After the twenty-fourth hour of life, there was a significant relationship between body T and both Mg (P < 0.05, b = -2.26) and P (P < 0.05, b = -6.54), as well as between body mass and Ca (P < 0.001, b = 0.89). After the forty-eighth hour of life, statistically significant correlations between body mass and Na (P < 0.05, b = 25.72), P (P < 0.05, b = 4.92), and Ca (P < 0.001, b = 1.61) became apparent. At this point, K showed a significant dependency on T (P < 0.05, b = -0.80). It may thus be hypothesized that in the first phase following birth, disturbances in temperature regulation exert a primary influence on the level of neonatal vitality, whereas body weight becomes a deciding factor at a later point in time.

Animals↗

PubMed2003

Cervimetry and ultrasonographic observations of the cervix regression in dairy cows during the first 10 days post partum.

The aim of this study was to describe the involution process of the bovine cervix during the first 10 days post partum by using an intracervically introduced gauge and transrectal ultrasonography. Twenty-five pluriparous Holstein Friesian cows were included, which were randomized into three groups: group 1 (n = 10): transrectal ultrasonographic presentation of the formation of cervical folds; group 2 (n = 10): measurement of the reduction of the canalis cervicalis using an intracervically introduced gauge. The examinations were performed directly after expulsion and 2, 4, 6, 8, 12, 16, 18 and 24 h post partum, and in intervals of 24 h up to the tenth day. The involution process can be divided into four phases: 1: fast reduction up to the sixth hour; 2: protracted reduction up to the second day without constant formation of folds; 3: protracted reduction up to the seventh day with constant formation of folds; 4: re-opening of the canalis cervicalis maintaining the structure of the folds. The reduction process (phase 1- phase 3) can be shown as the sum of two exponential functions with different grading coefficients: y = reduction 1 x e(-b1 x t) + reduction 2 x e(-b2 x t). Reduction 1 is reduction in cm during the first phase and reduction 2 is reduction in cm during the second and the third phase. Group 3 (n = 5): to exclude an influence of the high frequency of examinations on the involution process the cows were examined immediately after parturition and on the fifth and tenth day postpartum using the same method as in groups 1 and 2. In conclusion, the involution process of the bovine cervix guarantees a fast protection of the cavum uteri and a drainage of the lochia at the end of the early puerperium. The re-opening phase after the seventh day has not yet been described in any other species and can be interpreted as the adaptation to the exsudative puerperium in the cow.

Animals↗

PubMed2003

Investigations on the re-establishment of the positive feedback of oestradiol during anoestrus in the bitch.

To test for the re-establishment of the positive feedback of oestradiol (E2) during anoestrus in the dog, the hypothalamo-pituitary-ovarian axis of five beagle bitches was challenged by treatments with oestradiol benzoate (EB), mimicking the course of the pro-oestric E2 secretion. Treatments in anoestrus started 7 days following the decline of progesterone (P) <1 ng/ml; they were repeated in 5 week intervals until onset of pro-oestrus; another treatment was performed during dioestrus 50 days after onset of the preceding pro-oestric bleeding. Each dog served as its own control by receiving vehicle-treatments in one of the following cycles. Each observation period covered a time window of 168 h and blood samples were collected for the determination of luteinizing hormone (LH), follicle-stimulating hormone (FSH) and E2 in 6 (0-24 h) and 8 h (24-168 h) intervals. In the control periods and as indicated by the parameters area under curve (AUC), basal and maximal values, the availability of LH, FSH and E2 decreased from dioestrus to early anoestrus to increase again during the course of anoestrus (p < 0.05), indicating a gradual desensitization of the hypothalamus towards the negative feedback of oestradiol. At all times treatments with EB lowered the availability of FSH (decreased AUC and basal levels). A delay in the occurrence of the first LH peak after treatments with EB (p < 0.001) and decreased maximal values (p < 0.001) indicated a suppression of the LH-release. In no case treatment with EB led to a pre-ovulatory like LH-surge. In each dog the last trial with EB in anoestrus passed over into pro-oestrus/oestrus, with a reduced AUC and peak value of the pre-ovulatory LH-surge being the only differences to the control group. The observed differences in the response of LH and FSH to treatments with EB point towards subtle differences in the mechanisms controlling the release of these two hormones during anoestrus. From the data obtained, it may be concluded that the time window for E2 to act via a positive feedback seems to be very small and restricted to the end of anoestrus, and that full follicular function is a pre-requisite to allow for this phenomenon.

Anestrus↗

PubMed2003

[The regional differences of the pH-value in the vagina, cervix, and uterus of cows during interestrus].

This study aimed to ascertain the pH value of the vagina, cervix, and uterus in cows during interoestrus. Measurements were made with an ambulant, digital pH meter with a flexible probe and a measuring frequency of one value per second. The genital tract (vagina, cervix, uterus) of 50 cows were analyzed with this instrument immediately post mortem. The sexual health of the animals was evaluated via clinical, histological, and microbiological tests. Statistically significant regional differences in the pH value were documented (p < 0.01). Whereas a decrease was measured between the values for the vagina (6.92 +/- 0.51) and the cervix (6.22 +/- 0.31), increased values were measured in the uterus (6.62 +/- 0.32). The physiological pH value in the genital tract of the cow should be taken into consideration for the development of new therapeutic measures in terms of the local application of probiotically active bacterial strains.

Animals↗