Ovarian follicular dynamics in buffalo cows (Bubalus bubalis).

Follicular growth in Egyptian buffalo cows was monitored using genital tracts from 200 buffalo cows collected immediately after slaughter. According to the morphological appearance of the corpus luteum (CL), the corresponding oestrous cycle was divided into four stages: A (days 1-4), B (days 5-10), C (days 11-17) and D (days 18-21). Within these stages the follicular population on the ovaries was evaluated and the dominant follicle (DF) determined in all recovered ovaries. The functional status of the DF and the largest sub-dominant follicles was examined by histological examination in 31 cases, and Radio Immunoassay (RIA) analyses for estradiol-17beta (E2) and progesterone (P4) was performed in the follicular fluid in 23 of the DF. The results showed that DFs changed their endocrine character within the stages of the oestrous cycle. The DFs between days 5 and 10 were functionally active (E2-dominant; non-atretic) in most of the cases. Between days 11 and day 17 half of the DFs became functionally inactive (P4-dominant; atretic). At days 18-21 all of the DF became functionally active and non-atretic. In the specimens that carried two large follicles one of them was regularly atretic and P4-dominant whereas the other was non-atretic and E2-dominant. Between days 18 and 21 all ovaries examined showed at least one large follicle. These findings suggest that in most of the cases follicular dynamics occurs in two wave-like patterns in the Egyptian buffalo cows.

Morphological and functional characteristics of the dominant follicle and corpus luteum in cattle and their influence on ovarian function.

Predicting the functional activity of a dominant follicle (DF) and corpus luteum (CL) might be important before starting a superovulation regime or a synchronization program. The DF and CL were characterized morphologically by using ultrasonography and were characterized functionally by estimating the estradiol-17beta/progesterone (E2/P4) ratio. Their influence on ovarian function was estimated through their ability to ovulate at different stages of development in response to PGF2alpha-application. A total of 47 Holstein Friesian (35 cows and 12 heifers) were used in two experiments. In Experiment 1, 25 animals were examined by daily transrectal palpation and ultrasonography to follow the morphological development of the DF. The status of the DF was categorized into 3 groups (A1, B1, C1). The A1 group (n=7) contained animals with DF in the growing phase or in early static growth phase for less than 3 days. Group B1 (n=13) included animals with DF in static growth phase for 3 to 4 days, while Group C1 (n=5) comprised animals with DF keeping a plateau for more than 4 days or animals with DF in the regression phase. The DF were aspirated transvaginally and the follicular fluid (FF) was analyzed for E2 and P4. In Experiment 2, 22 animals were included. As in Experiment 1, the animals were classified into three groups (A2, n=10; B2, n=5; C2, n=7). They were treated by a single dose of PGF2alpha (25 mg, i.m.) between Days 8 and 12 of the cycle. Results showed that luteolyses occurred in all animals. The DF, which were in growing or in early static growth phase < 3 days were always E2-dominant (E2 > P4) and ovulated after PGF2alpha-application in 6/8 of cases and persisted in 2 (Group A2). The DF persisting > 4 days or that had been in regression were always P4-dominant. This type of DF regressed after PGF2alpha-application (Group C2). The DF in early static growth phase for 3 to 4 days in 5/13 cases were E2-dominant and in 8/13 cases were P4-dominant. This type of DF ovulated in 3/5 cases and regressed in 2/5 cases after PGF2alpha-application (Group B2). These results suggest that the DF is morphologically and functionally defined as long as the DF is in the growing or early static growth phase (A1, A2) for at least 2 days or if the DF is in regression (C1, C2). However, when the DF is in the static growth phase for 3 or 4 days (B1, B2), their morphological and functional characteristics are different. The CL controlls ovulation in the A and C groups and plays an abettor's roll in the B-group.

[Influence of changing oral mineral supply on kidney functions including renal fractional excretion of calcium, magnesium and phosphate in cows]. / Einfluss wechselnder oraler Mineralstoffzufuhr auf Nierenfunktionen einschliesslich renaler fraktioneller Exkretion von Ca, Mg und Phosphat bei Kühen.

The influence of normal (100%), reduced (50%), or increased doses (200%) of mineral content in food on selected kidney functions and on serum values of calcium, magnesium, phosphate and osmolality was tested in cattle (n = 6; age: 3-5 1/2 years; metabolic body mass: 106-132 kg0.75; non-pregnant, non-lactating) over 7 weeks. During the 19-day period of reduced mineral supply glomerular filtration rate, urine osmolality, 24-hour urine creatinine amount and serum electrolyte concentrations (exception: total magnesium) remained without significant deviations from the initial physiological values. In contrast to these results, the values of 24-hour urine volume, 24-hour urine osmolyte, serum/urine-ratio of creatinine, FECa and FEMg were significantly reduced. During the 15-day feeding period with over-supply of minerals the parameters 24-hour urine volume, serum/urine-ratio of creatinine, FECa, FEMg and FEPhosphate rose significantly. The proven influence of the supply with minerals on the renal electrolyte elimination can be used for the diagnosis of disturbances of mineral-feeding in "kidney-healthy" cattle.

[Is there a predictable correlation between time of birth, birth and the puerperal period and clinical and hormonal findings in horses?]. / Können beim Pferd der Zeitpunkt der Geburt sowie der Verlauf von Geburt und Puerperalphase klinisch oder hormonanalytisch vorausgesagt werden?

The investigations were done on 108 mares (78 warm-blooded horses, 25 cold-blooded horses and 5 trotters). To pursue the question in the title, progesterone and estradiol values in jugular vein-blood were examined starting from 30 days before the calculated date of parturition until 30 days after that event. In parallel to that Ca/Mg ratio was measured by means of a semiquantitative test-strip in the milk. Clinical signs of the birth, parturition itself and the post partum period were recorded. In respect to the P4 and E2 values it was that the P4:E2 ratio changed towards parturition in favour to E2 which was interpreted as a sign for the beginning of labour contractions as well as a signal to the ovarian hormonal activity and feed-back regulation. The "predict of the foal-test" by measuring Ca/Mg ratio is helpful only in combination with clinical findings. This test can be used for the decision to induce parturition. Concerning the colour and viscosity of the milk, it was observed to change from grey-aqueous 48 h a.p. through grey-brownish 24 h a.p. to white-yellow and viscous 12 h a.p. The results show that heavy mares more often retain the fetal membranes. They often bear lighter offspring with equally lighter fetal membranes, and the surfaces of the microvilli of the microcotyledonas seem to be smaller. Beside this it is concluded that during pregnancy disturbances in the fetomaternal relations probably exist as a result of a deficiency in placental development that finally results in retention secundinarum.

[Feasibility of detecting steroid hormones in cattle feces for monitoring ovarian function]. / Zur Aussagefähigkeit von Steroidhormonen im Kot von Rindern für deren Ovarfunktionen.

Faecal material from four non pregnant cows was withdrawn in two-day intervalls during a four-week period. At the same time bloodsamples were taken to monitor the ovarian function. Clinical and ultrasonographical examinations were recorded in parallel. To look for the stability of the faecal steroid analogues for P4 (Progesterone) and E2 (Estradiol-17 beta) faecal material was stored at 37 degrees C and samples from that analyzed in two-day intervals. The P4 (Progesterone)-analogues values in the faeces showed good correlation to cycling ovarian functions as monitored by bloodlevels from P4, clinical examination and ultrasonography. In contrast the E2-analogues values showed no cycling pattern. One cow however showed ovarian cysts which was monitored in the P4 values for blood and faeces. Concerning the stability of the steroid analogues it could be demonstrated that the P4-values show a steady decrease with minimum values of 20 ng/g dry material. During the first four days after sampling reliable values for clinical interpretations can be found. The concentrations for E2 are very inconstant and so far not of interest. The investigation shows that the faecal steroid P4 can be used for monitoring ovarian function. It has to be analyzed within four days after sampling when stored at room temperature.

[Analysis of the influence of temperature on the stability of sex steroids in cow feces]. / Verlaufsuntersuchungen zum Temperatureinfluss auf die Stabilität von Sexualsteroiden im Kot von Kühen.

Up to the present natural and synthetic steroids have only rarely been considered a cause of disturbances of sexual behavior and anomalies of sex organs. The increasing environmental contamination with chemicals showing estrogenic effects underlines the importance of further investigations in that matter. Therefore, the concentrations of estrogens and progesterone in the faeces of cattle were examined over a 13 weeks period. The values obtained are presented as equivalents of the standard substances estrone and 4-pregnene-20 beta-ol-3-one. The samples were stored in a refrigerator or incubator at temperatures of 5 degrees C and 30 degrees C, respectively, and the investigations were carried out by using an enzyme-immunoassay. Estrogen and progesterone concentrations decreased more rapidly when incubation was performed at 30 degrees C as compared to storage at 5 degrees C, and estrogen values declined more slowly than those of progesterone. When keeping the samples at 5 degrees C the estrogen concentrations decreased to below the basal values only beyond the eleventh week of storage. In contrast, comparable concentrations were already obtained during the third week of the experiment if the samples were stored at 30 degrees C. Progesterone levels decreased to below the basal values during the fourth week of storage at 5 degrees C and during the second week at 30 degrees C.

[Significance of biotechnology in reproductive biology and veterinary medicine]. / Zur Bedeutung von Biotechniken in der Fortpflanzungsbiologie und Veterinärmedizin.

In the last decade a good number of biotechnical methods have been developed. They are available in medical, biological, and ecological fields of work as well as techniques that can replace animal experiments. These methods have been developed on the basis of researchwork in andrology (AI and cryoconservation of spermatozoa), endocrinology (hormonal control of reproduction) and the availability of industrial produced hormones and their analog. On the other hand practical clinical techniques for examination like the availability of sonography advice and clinical practical techniques for non-surgical recovery and transplantation of gamets and embryos have been the prerequisites for a successful work in this field of action. These fields of action are extended from breeding aspects (genetical progress) over the control of epidemics to the exportation of genetic material (especially developing countries to overcome hygienic and adaptation problems), the creation of gen-pools (conservation of breeds-species) and as well as the elimination of genetic defects like BLAD or DUMPS by help of PCR-techniques or the identification of positive characters like milk components and sexing of embryos. The industrial use of bioproducts produced by especially designed biosystems is in work but in Germany not possible by reasons of legislative restrictions. In the light of these developments the veterinary fields of work should be discussed and focussed towards an understanding that the veterinarian should be active and in a polposition in the processing of reproduction and production and presentation of food of animal origin by using these new technologies.

[The use of sonography in the andrologic diagnosis in bulls, pathologic changes and false artifacts]. / Zur Anwendung der Sonographie in der andrologischen Diagnostik beim Bullen, pathologische Veränderungen und verfälschende Artefakte.

The real-time ultrasonography is a tool for producing additional information to the clinical andrological examination in bulls. To find out the significance and the limits of this techniques these experiments have been carried out. In the testicles of slaughtered bulls artefacts were produced by injecting either crystalline, metallic or aqueous solutions respectively. The effect of metallic or crystalline solutions are good to be seen whereas water or gas are giving not so clear echograms. In the second part of the experiment 100 pairs of testicles where examined and compared to in situ examinations and histological preparations. In 95 cases of the examined animals pathological findings became evident both by sonographic examination and histologically, alterations that must be at least regarded as suspicious with respect to bulls to be used for reproduction.

[Fertility in mares after disturbed or undisturbed puerperium; evidence from clinical, microbiologic and hormone analysis]. / Fruchtbarkeit bei Stuten nach gestörtem oder ungestörtem Puerperium; Aussagekraft klinischer, mikrobiologischer und hormonanalytischer Untersuchungen.

Because of the mare's ability to conceive very soon post partum a thoroughly performed control of the puerperal period is of particular importance. In addition to cytological and histological examinations of the uterus, rectal palpation and vaginoscopic inspection as well as microbiological examinations of uterine swabs and the evaluation of the mare's hormonal status during the puerperal period provide useful information which can be used either prognostically or to initiate a specific therapy. 55 mares were examined on days 3, 6 and 9 post partum. Rectal palpation, vaginoscopic inspection, microbiological examination of uterine swabs and determination of progesterone-(P4)- and estradiol-(E2)-levels in the peripheral blood were performed on all the three days. On day 18 after the last breeding the mares were checked for pregnancy by ultrasonic echography. We observed many cases of heavy bacterial contamination of the uterine contents during the puerperal period up to the foal heat. Especially coliforms and beta-hemolytic streptococci were often found. However, these contaminations could not be proven to interfere with fertility rates during the first post partum estrus periods. Dystocia and retained placenta had a strong influence on the hormonal situation of mares during the puerperal period. In addition to this we found disturbed involution of the genital system in these mares. Much higher pregnancy rates at foal heat were detected after a rapid onset of ovarian activity post partum especially during May, June and July, compared to mares with delayed onset of ovarian activity.(ABSTRACT TRUNCATED AT 250 WORDS)

[Fertility in mares after an disturbed as well as an undisturbed puerperium. Significance of histological and cytological examinations of the uterus]. / Fruchtbarkeit bei Stuten nach gestörtem bzw. ungestörtem Puerperium. Aussagekraft histologischer und zytologischer Untersuchungen des Uterus.

Because of the mare's ability to conceive very soon post partum a thoroughly performed control of the puerperal period is of particular importance. Cytological examinations of uterine content and histological examinations of uterine biopsy specimens provide more detailed information than microbiological examinations of uterine swabs. Uterine content and uterus biopsy specimens of 55 mares were examined histologically on days 3, 6 and 9 post partum. We observed a heavy polymorphonuclear reaction of the endometrium following disturbed puerperal processes especially in cases of retained placenta. This reaction of the endometrium as well as a delayed regeneration of the uterine epithelium and the uterine gland epithelium resulted in significantly lower fertility rates at the first post partum oestrus. In such cases the foal heat should therefore not be used for breeding.