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Histomorphometric analysis of the omasum of sheep during development
1993
Franco, A. | Robina, A. | Regodon, S. | Vivo, J.M. | Masot, A.J. | Redondo, E.
Histomorphometric and scanning electron microscopic analyses were performed on 74 embryos and fetuses and 20 sheep (early postnatal to adult age). Histologic differentiation of the omasum took place at 33 days of fetal life, with the appearance of first-order laminae. Second-, third-, and fourth-order laminae appeared at 39, 50, and 59 days, respectively. Neutral mucopolysaccharides first appeared in epithelial cells at 46 days of fetal life, decreasing quantitatively until birth, before subsequently stabilizing in postnatal life. Acid mucopolysaccharides, mucins, and mucoid compounds were not detected. Growth curves and formulas were constructed for each tissue layer. Initial tests involved multiplicative (y = axb), exponential (y = EXP [a + bx]), linear (y = a + bx), and polynomial models [y = a + bx + cx(2) + dx(3)].
Afficher plus [+] Moins [-]Histomorphometric analysis of the rumen of sheep during development
1992
Franco, A. | Regodon, S. | Robina, A. | Redondo, E.
Histomorphometric and scanning electron microscopic analyses were carried out on 74 embryos and fetuses and 20 sheep (early postnatal to adult age). Histodifferentiation of the rumen took place at 33 days of fetal fife. Ruminal pillars were observed at 42 days, and at 61 days, ruminal papillae appeared as evaginations of the epithelial stratum basale. Neutral mucopolysaccharides first appeared in epithelial cells at 46 days of fetal life; thereafter, numbers decreased gradually and subsequently stabilized in postnatal life. Acid mucopolysaccharides, mucins, and mucoid compounds were not detected. Age and diet were recognized as factors that determine the structure of the ruminal mucosa. Growth curves and formulas were set out for each tissue layer.
Afficher plus [+] Moins [-]Hemostasis development in the lamb fetus and neonate
1989
Moalic, P. | Gruel, Y. | Foloppe, P. | Delahousse, B. | Leclerc, M.H. | Leroy, J.
Fetal and neonatal lamb hemostasis were studied from the 60th day of pregnancy to birth. Platelet counts and blood coagulation, as assessed by tests such as recalcification time and thromboelastography, were similar in fetuses, neonates, and adult sheep. The values of coagulation factors were low, ie, vitamin K-dependent Factors II, VII, IX, and X remained unchanged (30 and 40% of adult reference values) until the last 10 days of gestation, and then increased until birth (40 to 60%). Values of fibrinogen and Factor V followed a similar pattern, although their activities became identical to adult values at birth. Also, we measured values of protein C and antithrombin III, which are synthesized by the liver. The importance of hepatic failure and fetal vitamin K deficiency were discussed. Factors VIII and XII activities increased gradually during pregnancy to reach adult values at birth. Fetal fibrinolytic activity increased. This could not be explained by the values or tissue-type plasminogen activator (it was not detectable) or by the presence of its fast-acting inhibitor, whose concentration did not decrease.
Afficher plus [+] Moins [-]Accuracy of transvaginal ultrasonography for early pregnancy diagnosis in Attappady black goats
2017
Philip, Laiju M. | Abhilash, R. S. | Francis, Bastin P.
Transabdominal ultrasonography has been popularly used in animal reproduction for the assessment of pregnancy status and foetal viability where as transvaginal method for pregnancy diagnosis is rarely used for pregnancy diagnosis in goats. The study was conducted in 74 Attappady Black goats from Government Goat Farm, Attappady and Livestock Research Station, Thiruvizhamkunnu to evaluate the accuracy of trans-vaginal methods and to identify the fetal characteristics from day 20 to 75. Transvaginal ultrasonographic examination was performed using endocavity transducer with frequency of 6.5 to 8 MHz. Observations were made in all the pregnant does at three different stages of pregnancy i.e., 20-35 days, 35-55 days and 55-75 days. Does were diagnosed as pregnant from the observation of gestational sac, embryo or foetus, embryonic or foetal heartbeat, placentomes or foetal skeleton. Sensitivity, specificity, positive predictive value, negative predictive value and overall accuracy along gestation period were 98.03, 92.3, 96.15, 96 and 95.62%, respectively. It is concluded from the present study that transvaginal ultrasonography can be used for herd pregnancy diagnosis at early stages from day 20 to 45 of pregnancy diagnosis in goats.
Afficher plus [+] Moins [-]Effect of diethylstilbestrol or zeranol on fetal development, gestation duration, and number of offspring in NMRI mice
1995
Perez-Martinez, C. | Garcia-Iglesias, M.J. | Bravo-Moral, A.M. | Ferreras-Estrada, M.C. | Martinez-Rodriguez, J.M. | Escudero-Diez, A.
Objective--To evaluate the effects of diethylstilbestrol (DES) or alpha-zearalanol (zeranol) on fetal development, gestation duration, and number of offspring. Design-Study effects of prenatal administration of DES or zeranol on various pre- and perinatal variables in an experimental group of mice, compared with effects in a control group. Animal--Pregnant NMRI mice. Procedure--Diethylstilbestrol or zeranol (150 mg/kg of body weight) or vehicle (controls) was administered sc to pregnant mice on days 9 and 10 of gestation. Fetuses from pregnant mice of each group were counted and weighed, and their size and head length were recorded. Additional pregnant mice delivered their fetuses naturally, and pups from each group were counted and their sex was determined. At the end of gestation, abortions were evaluated. All data were statistically analyzed. Results--Mean number of fetuses was significantly lower (P < 0.0001) in DES-treated (4.59 +/- 0.48) than in control mice (8.33 +/- 0.49). Both estrogenic substances significantly reduced fetal size and weight (P < 0.0001), compared with control mice. Diethylstilbestrol significantly increased abortion frequency (P < 0.0001) and gestation duration (P < 0.0001), compared with values for control mice. A reduced number of live pups (P < 0.0001) from pregnant mice administered DES (5.48 +/- 0.38) or zeranol (5.97 +/- 0.49) was observed, compared with control mice (8.52 +/- 0.50), because of reduced number of male offspring (P < 0.0001). Conclusions--Diethylstilbestrol or zeranol administered during mid-pregnancy leads to decreased fetal weight and size and lower numbers of male offspring at birth. Likewise, DES induced a significant increase in abortions and gestation duration.
Afficher plus [+] Moins [-]Safety of albendazole in developing bovine fetuses
1993
Theodorides, V.J. | Carakostas, M.C. | Colaianne, J.J. | Freeman, J.F. | Page, S.W.
Albendazole, administered orally at a dose rate of 25 mg/kg of body weight to presumed pregnant cows or heifers on days 21, 31, 41, 51, and 61 of gestation, did not induce toxicosis in embryos or fetuses, and all calves born were structurally normal. Albendazole administration at a rate of 25 mg/kg to cows at 7 and/or 14 days of gestation decreased the apparent conception rate (ie, embryolethality), but did not have a teratogenic effect. Apparent embryolethality was greater in cows administered 25 mg/ kg only on day 14, compared with those administered the drug only on day 7. Single dosage of 25 mg/kg given in the final 3 months of gestation did not induce abortion. There were no adverse effects of albendazole at a dosage of 10 or 15 mg/kg on developing embryos or fetuses when administered to presumed pregnant cows at various times in early gestation.
Afficher plus [+] Moins [-]Effect of Fusarium roseum corn culture containing zearalenone on early pregnancy in swine
1982
Long, G.G. | Diekman, M. | Tuite, J.F. | Shannon, G.M. | Vesonder, R.F.
A corn culture of Fusarium roseum was added to a standard corn-soybean swine gestation ration. Low, middle, and high dosage mixed feeds contained 7, 38, and 64 mg of zearalenone/kg of feed (7, 38, and 64 ppm) and 0.5, 2.5, and 4.5 mg of deoxynivalenol/kg, respectively. Control feed was the standard ration without added F roseum corn culture. Mature gilts were bred by natural service and fed control or F roseum molded feed from 3 to 34 days after breeding. The main effect of the molded feed was an inhibition of fetal development, with decreased numbers of fetuses present in treated animals at slaughter (38 to 43 days after breeding). Normal litters were present in 7 of 8 control animals, in 2 of 4 gilts given the low-dosage feed, in 1 of 4 gilts given the medium dosage, and in 0 of 4 given the high-dosage feed. Corpora lutea were maintained in all treated animals, as evidenced by serum progesterone concentrations. Serum estradiol concentrations were decreased in gilts in the middle- and high-dosage groups. The genital system of the gilts fed low- and middle-dosage feeds had a gross and microscopic appearance similar to that of the pregnant controls and reflected prolonged progesterone stimulation. Morphologic changes in the genital system of the high-dosage group were intermediate between changes induced by progesterone and those induced by estrogen. Clinical signs of hyperestrogenism and partial feed refusal were noticed in only some of the high-dosage group animals.
Afficher plus [+] Moins [-]Evaluation of use of progesterone to counteract zearalenone toxicosis during early pregnancy in gilts
1991
Green, M.L. | Stouffer, D.K. | Scheidt, A.B. | Long, G.G. | Diekman, M.A.
It has been shown that zearalenone disrupts early pregnancy in swine without altering intrauterine content of estradiol 17 beta or progesterone, embryo migration, or estradiol-17 beta thesis by blastocysts. However, serum concentrations of progesterone were reduced 2 to 3 weeks after mating in gilts that ingested zearalenone. Therefore, progesterone was administered to gilts during early pregnancy to determine whether it could counteract the detrimental actions of zearalenone on embryonic development. Thirty-two crossbred gilts (Hampshire X Chester White X Yorkshire X Duroc) were assigned randomly to a 2 X 2 factorial arrangement of treatments: zearalenone (Z); zearalenone plus progesterone (ZP); progesterone (P); or control (C). From postmating days 4 to 15, Z- and ZP-treated gilts were fed 1 mg of Z/kg of body weight, and P-treated and C gilts were fed ethanol as vehicle in a corn-soybean diet. On postmating days 3 to 15, P- and ZP-treated gilts were injected IM with 100 mg of progesterone, and C and Z-treated gilts were injected with progesterone carrier (15% ethanol, 15% benzyl alcohol, 70% propylene glycol). Blood was collected from gilts by puncture of the jugular vein daily from days 3 to 15, on alternate days from days 17 to 31, and then twice weekly until the end of the experiment. Fetal development was assessed in Z and ZP-treated gilts on postmating day 47.6 +/- 2.9 by cesarean section and in P-treated and c gilts at slaughter on postmating days 51.2 +/- 3.2. Serum concentrations of progesterone in P-treated gilts were greater on days 7 to 8, 10 to 15, 17, and 19 than in C gilts. Serum concentrations of progesterone were greater on days 8, 10, and 12 in ZP-treated than in C gilts. However, serum concentrations of progesterone were lower in ZP-treated gilts than in C gilts on postmating days 19 to 31. Serum concentrations of progesterone were lower in Z-treated gilts than C gilts on postmating days 15, 17, and 19. At slaughter or cesarean section, viable fetuses were not found in Z-treated gilts, but 80% of the C and P-treated gilts had viable fetuses. All Z-treated gilts were classified as pseudopregnant because uteri were turgid and the ovaries had functional corpora lutea. Uteri of ZP-treated gilts appeared normal. Corpora lutea of pregnancy had regressed by postmating day 35 in 7 of 8 ZP-treated gilts. Crown-to-rump length was similar between P-treated and C gilts (94 vs 92 mm). Fetal weight was similar between P-treated and C gilts (70 vs 62 g). These data demonstrate that 100 mg of progesterone/d failed to counteract the adverse effects of 1 mg of Z/kg of body weight on early pregnancy in primiparous gilts.
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