Endocrine and sperminogenic testicular function. 8. Relationships between testicular and plasma testosterone concentrations as well as between the number of Leydig cells in testicular tissue and their cell nucleus volume in boars of different ages]

Testicular tissue and blood samples (V. spermatica interna) were taken from 32 boars during castration. The animals were different age groups. Against this background, studies were conducted into the correlations between testicular and plasma testosterone, on the one hand, and the amount of interstitial cells of Leydig in testicular tissue as well as the latters' cell nuclei volumes, on the other. The results seemed to support the conclusion that any age-dependent increase of testicular and plasma testosterone concentrations was caused unambigously by an absolute increase in volume of androgenic testicular tissue, in concomitance with testicular growth, in other words, by rise in the total number of interstitial cells of Leydig.     

Monthly model for genetic evaluation of laying hens 1. Fixed regression.

1. This paper addresses the possibility of using a monthly model for the genetic evaluation of laying hens, based on the definition of a test day model with fixed regression as used in dairy cattle, in which monthly records were treated as repeated measurements of the same trait. 2. Production records of 6450 hens, daughters of 180 sires and 1335 dams were analysed using an animal model with restricted maximum likelihood (REML). The traits considered were individual monthly egg production and cumulative egg production in 11 months. Four different models were fitted to various combinations of monthly and cumulative records. The covariates were derived from the regression of Ali and Schaeffer (1987). 3. Spearman rank correlations were computed to compare breeding values from different models. Two types of correlations were computed: between individual breeding values and between sire breeding values based on subsets of full-sib records. 4. The results indicated that a monthly model with nested covariates produced higher heritability and permanent environmental variance than the models with non-nested or without covariates. The estimates of heritability obtained from monthly model were lower than the estimates from the cumulative model. The monthly model resulted in higher correlations of sire breeding values between two subsets of full-sib records than those from cumulative models. 5. In conclusion, the monthly model with nested covariates appears to be better than the model with non-nested covariates or without covariate. Although the heritability estimates obtained from the monthly model were lower, the monthly model with nested covariates could be better than the cumulative model for genetic evaluation of laying hens in the 1st cycle of laying period when using either full or part records. The use of information from odd months of production could be of interest for the evaluation of full records.     

Feline relapsing polychondritis: two cases and a review of the literature

Only 11 reports of cats with relapsing polychondritis (RPC) were found in the literature. We describe two additional cases and provide a review of the literature. Predominantly young to middle aged cats are affected (range 1.5 to 14.5 years, median 3 years). There is no sex predilection for feline RPC. In all cats with feline RPC, the ears were affected. The findings in one of our cases and one case in the literature raise the question if other organs such as the joints, the eyes or the heart may be involved in feline RPC. The histological lesions observed in biopsy samples of the ears were similar in all cats. Glucocorticoids were not effective in the treatment of RPC. Dapsone appeared to result in some clinical improvement but side effects were observed in one of four cats. Some cats improved without treatment.     

Detection of anticoagulant rodenticides (4-hydroxycoumarins) by thin-layer chromatography and reversed-phase high-performance liquid chromatography with fluorescence detection

The detection of 4-hydroxycoumarin rodenticides in poisoned domestic animals requires a highly sensitive method as tissue and serum levels of anticoagulants may be very low owing to rapid elimination, metabolism or post-mortem degradation. Thin-layer chromatography (TLC) and reversed-phase high-performance liquid chromatography (RP-HPLC) with fluorescence detection were used to identify the anticoagulants in spiked tissues and in suspicious samples. The analysis of ten suspicious samples highlighted the limitations of both methods. Only the three samples of baits were found positive by TLC whereas one of the five anticoagulants was detected in eight samples by RP-HPLC with fluorescence detection. Therefore, RP-HPLC with fluorescence detection proved to be the more sensitive method for detecting low levels of 4-hydroxycoumarins in blood serum, liver and ingesta, whereas TLC is usually sufficient for analysing baits.Abbreviations RP-HPLC reversed-phase high-performance liquid chromatography - TLC thin-layer chromatography     

Description of the infection status in a Norwegian cattle herd naturally infected by Mycobacterium avium subsp. paratuberculosis

The Norwegian surveillance and control programme for paratuberculosis revealed 8 seroreactors in a single dairy cattle herd that had no clinical signs of Mycobacterium avium subsp. paratuberculosis (M. a. paratuberculosis) infection. Paratuberculosis had been a clinical problem in goats several years previously in this herd. All 45 cattle were culled and a thorough investigation of the infection status was conducted by the use of interferon-gamma (IFN-gamma) immunoassay, measurement of antibodies, and pathological and bacteriological examination. In the IFN-gamma immunoassay, 9 animals gave positive results, and 13 were weakly positive, while 19 animals were negative. In the serological test, 10 animals showed positive reactions, and 5 were doubtful, while 30 animals gave negative reactions. There appeared to be a weak trend toward younger animals having raised IFN-gamma and older animals having raised serological tests. Histopathological lesions compatible with paratuberculosis were diagnosed in 4 animals aged between 4 and 9 years. Three of these animals had positive serological reaction and one animal gave also positive results in the IFN-gamma immunoassay. Infection was confirmed by isolation of M. a. paratuberculosis from 2 of these 4 animals. One single bacterial isolate examined by restriction fragment length polymorphism (RFLP) had the same profile, B-C1, as a strain that had been isolated from a goat at the same farm several years previously. Despite many animals being positive in one or both of the immunological tests, indicative of a heavily infected herd, none of the animals showed clinical signs and only one cow was shown to be shedding bacteria. A cross-reaction with other mycobacteria might have caused some of the immunoreactions in these animals. It is also possible that the Norwegian red cattle breed is resistant to clinical infection with M. a. paratuberculosis.     

Ein Schnelltest zur Ermittlung der individuellen SO2-Empfindlichkeit bei Kiefern

Zusammenfassung Es wird eine Schnellmethode zur Rauchh?rteprüfung von Kiefernarten beschrieben, die vom Terminaltrieb abgetrennte, in Pillengl?ser gesteckte einj?hrige Kurztriebe verwendet. Die Nadeln reagieren auf akute SO₂-Immissionen kloneinheitlich und weitgehend in übereinstimmung mit der Mutterpflanze. Bei den Kurztrieben lassen sich endogene, vom Mutterbaum abh?ngige Differenzen in der Austrocknungsgeschwindigkeit nachweisen, die aber ohne wesentlichen Einflu? auf ihre Reaktion gegenüber SO₂ bleiben, sofern die Expositionsdauer kurzgehalten wird. Die entwickelte Methode ist schneller, wirtschaftlicher und auch zuverl?ssiger als Rauchh?rteprüfungen mit eingetopften Pflanzen. Sie testet lediglich die Reaktion auf akute Begasungen.

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Summary A short-time technique of testing pines for resistance against SO₂-emissions has been developed, using one-year-old needle fascicles, put into water-filled glass vials. Against actual SO₂-exposure, fascicles of the same tree react uniformly, and their reaction is very similiar to that of the parent tree. Besides, needle fascicles show endogenous clonal variation in the rate of drying out. This, however, does not influence the reaction against SO₂, provided the time of exposure is kept short. The new technique is quicker, accurate, and more economical than SO₂-tests with potted seedlings or graftings, but it only tests the reaction against short time-high doses exposure to SO₂.

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Durchgeführt mit finanzieller Unterstützung der Landesanstalt für Immissions- und Bodennutzungsschutz des Landes Nordrhein-Westfalen in Essen.