Badania nad hormonalnymi i klinicznymi aspektami indukowania porodow u krow

• Autorzy: Zdunczyk S
• Języki publikacji: PL

Abstrakty

PL

W celu realizacji przyjętych zadań badawczych przeprowadzono 3 doświadczenia. W doświadczeniu 1 badano wpływ niewielkiej dawki (10 mg) syntetycznego kortykosteroidu - triam- cinolonu - podawanego krowom 10 dni przed indukowaniem porodu analogiem PGF2α - cloprostenolem - na poziom progesteronu, PGFM, testosteronu i kortyzolu we krwi obwodo­wej oraz siarczanu estronu i estronu wolnego we krwi obwodowej i pobranej z żyły czczej tylnej. U 28 krów wprowadzono kaniule do żyły jarzmowej oraz do żyły czczej tylnej, przednio od ujścia żyły maciczno-jajnikowej, przez żyłę ogonową. Krowom grupy doświadczalnej (n = 14) podano 260. dnia ciąży 10 mg triamcinolonu i 270. dnia 500 μg cloprostenolu. Krowy grupy kontrolnej (n = 14) otrzymały - 260. dnia ciąży placebo i 270. dnia 500 ng cloprostenolu. Koncentrację hormonów oznaczono metodami RIA. Podanie triamcinolonu spowodowało wyraźny, stopniowy spadek poziomu progesteronu oraz wzrost poziomu siarczanu estronu i estronu wolnego. Poziom PGFM nie wykazał zmian. Koncentracja kortyzolu obniżyła się po podaniu triamcinolonu, a poziom testosteronu wykazał niewielki, przejściowy wzrost. U zwierząt kontrolnych spadek zawartości progesteronu i wzrost estrogenów były niewielkie, a koncentracja PGFM, testosteronu i kortyzolu nie uległa większym zmianom. W obu grupach krów koncentracja estrogenów była dwukrotnie wyższa w żyle czczej tylnej niż w żyle jarzmowej. Podanie cloprostenolu spowodowało gwałtowny spadek poziomu progesteronu u wszystkich zwierząt. W czasie porodu stwierdzono wzrost poziomu PGFM i kortyzolu. Po porodzie poziom estrogenów i testosteronu szybko się obniżył. Uzyskane wyniki wskazują, że podanie krowom 10 mg triamcinolonu na 10 dni przed indukowaniem porodu analogiem PGF2α powoduje zmiany hormonalne bardziej fizjologiczne pod względem okresu trwania niż przy indukowaniu porodu samym cloprostenolem. W doświadczeniu 2 badano przydatność premedykacji triamcinolonem do indukowania porodów w warunkach produkcyjnych. Badania przeprowadzono na 120 krowach. 40 zwierzę­tom podano - 260. dnia ciąży 10 mg triamcinolonu i 270. dnia 500 μg cloprostenolu (grupa Ta + PGF2α). Inne 40 krów otrzymało 260. dnia ciąży placebo i 270. dnia 500 μg cloprostenolu (grupa PGF2α), a pozostałe 40 krów - 260. i 270. dnia ciąży placebo (grupa kontrolna). Średni okres od podania cloprostenolu do porodu wynosił 31.0 ± 1.4 godz. u krów z grupy Ta + PGF2α i 36.4 ± 2.8 godz. w grupie PGF2α. Częstotliwość ciężkich porodów była statystycznie istotnie niższa (p ≤ 0.05) u krów, którym poród indukowano po premedykacji triamcinolonem niż u krów, którym poród indukowano samym analogiem PGF2α (2.5% wobec 12.8%). Odsetek zatrzymania łożyska wynosił w grupie krów z premedykacją triamcinolonem 14.5% i nie różnił się istotnie od grupy kontrolnej (7.5%). W grupie PGF2α częstotliwość występowania zatrzyma­nia łożyska wynosiła 80.0% i różniła się statystycznie wysoce istotnie (p ≤ 0.01) od pozostałych grup. Wydaje się, że premedykacja triamcinolonem może być przydatna do indukowania porodów u krów w warunkach produkcyjnych. W doświadczeniu 3 zbadano wpływ dopochwowej aplikacji analogu PGF2α- cloprostenolu u wysoko cielnych krów na poziom progesteronu we krwi i wywołanie porodów. Badania wyko­nano na 40 zwierzętach: 20 krów otrzymało 500 μg cloprostenolu dopochwowo i 20 krów - domięśniowo. Po 28 godz. od aplikacji poziom progesteronu u wszystkich zwierząt był niższy od 3.18 nmol/1. Poród został wywołany u 19 zwierząt po aplikacji dopochwowej i u wszystkich krów po podaniu domięśniowym. Okres od aplikacji cloprostenolu do porodu był zbliżony w obu grupach. Wyniki wskazują, że dopochwowa aplikacja cloprostenolu może być stosowana do indukowania porodów u krów.

EN

Three experiments were performed in order to answer the undertaken research questions. In experiment 1, the influence of a small dose (10 mg) of synthetic corticosteroid, triamcinolone acetonide, administered to cows 10 days prior to induction of parturition with PGF2α analogue cloprostenol, on the level of progesterone, PGFM, testosterone and cortisol in the peripheral blood and estrone sulphate and free estrone in the blood from the jugular vein and caudal vena cava was investigated. In 28 cows catheters were inserted into the jugular vein and into the caudal vena cava cranial to the origin of the uteroovarian vein through the tail vein. Experimental cows (n = 14) were given 10 mg of triamcinolone on 260th day of pregnancy and 500 μg of cloprostenol on 270th day. Control cows received placebo on 260th day of pregnancy and 500 μg of cloprostenol on 270th day. The hormone concentrations were determined by RIA methods. The administration of triamcinolone caused a significant, gradual decrease in proge­sterone and increase in estrone sulphate and free estrone. The PGFM level showed no changes. The concentration of cortisol was depressed after administration of triamcinolone and the level of testosterone showed a slight, transient rise. In control animals the decrease of progesterone and the increase in estrogens were low and the concentrations of PGFM, testosterone and cortisol did not altered significantly. The concentration of estrogens in the caudal vena cava was twice that in the jugular vein in both groups. The application of cloprostenol caused a rapid decline in progesterone in all cows. During parturition, increases in PGFM and cortisol levels were found. After calving, the levels of estrogens and testosterone rapidly decreased. The obtained results indicate that treatment with 10 mg of triamcinolone ten days prior to induction of parturition with cloprostenol causes hormonal changes that are more physiological - considering their duration - than those preceding parturition induced with cloprostenol alone. In experiment 2, the usefulness of triamcinolone pretreatment for induction of parturition under productive conditions was studied. The investigation was carried out on 120 cows. 40 cows were given 10 mg of triamcinolone on 260th day of pregnancy and 500 μg of cloprostenol on 270th day (group Ta + PGF2α). Other 40 cows received placebo on 260th day of pregnancy and 500 μg of cloprostenol on 270th day (group PGF2α) and the remaining 40 cows received placebo on 260th and 270th day (control group). The mean interval from application of cloprostenol to parturition was 31.0 ± 1.4 h in group Ta + PGF2α and 36.4 ± 2.8 h in group PGF2α. The frequency of dystocia was significantly lower (p ≤ 0.05) in cows with parturitions induced after triamcinolone pretreatment, compared with cows with parturitions induced with prostaglandin F2α analogue alone (2.5% vs 12.8%). The percentage of retained placenta was 14.5% in cows with triamcinolone pretreatment and did not differ from the control group (7.5%). The cows in the PGF2α group had an 80.0% incidence of retained placenta, which was different (p ≤ 0.01) from the remaining groups. It appears that the triamcinolone pretreatment may be usefulness for induction of parturition in cows under productive conditions. In experiment 3, the effect of intravaginal application of PGF2α analogue, cloprostenol, on the progesterone levels in blood and induction of parturition in late pregnant cows was investigated. The study was carried out on 40 animals. 20 cows received 500 μg of cloprostenol intravaginally and 20 cows - intramuscularly. After 28 h from the application, the progesterone levels were below 3.18 nmol/1 in all animals. Parturition was induced in 19 cows after intravaginal application, and in all cows after intramuscular application. The interval from cloprostenol treatment to parturition was similar in both groups. The results indicate that intravaginal application of cloprostenol may be used for induction of parturition in cows.

Słowa kluczowe

PL

bydlo; krowy; indukowanie porodu zob.wywolywanie porodow; wywolywanie porodow; porod indukowany; hormony steroidowe; Cloprostenol; Triamcinolon; estrogeny; poziom hormonow

EN

cattle; cow; parturition induction; induced parturition; steroid hormone; Cloprostenol; Triamcinolone; estrogen; hormone level

• Wydawca: -
• Czasopismo: Acta Academiae Agriculturae ac Technicae Olstenensis. Veterinaria
• Rocznik: 1996
• Tom: 22,Suppl.D
• Opis fizyczny: s.1-38,rys.,tab.,bibliogr.

Twórcy

autor

Zdunczyk S

• Akademia Rolniczo-Techniczna, Olsztyn

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