{"id":2160,"date":"2023-10-09T11:13:02","date_gmt":"2023-10-09T09:13:02","guid":{"rendered":"https:\/\/www.rumexperts.vet\/?post_type=training&#038;p=2160"},"modified":"2024-03-16T10:02:28","modified_gmt":"2024-03-16T09:02:28","slug":"et-pourquoi-pas-une-injection-de-gnrh-lors-de-linsemination","status":"publish","type":"training","link":"https:\/\/www.rumexperts.vet\/en\/training\/et-pourquoi-pas-une-injection-de-gnrh-lors-de-linsemination","title":{"rendered":"ET POURQUOI PAS UNE INJECTION DE GNRH LORS DE L\u2019INSEMINATION ?"},"content":{"rendered":"<div class=\"fusion-fullwidth fullwidth-box fusion-builder-row-1 fusion-flex-container has-pattern-background has-mask-background nonhundred-percent-fullwidth non-hundred-percent-height-scrolling\" style=\"--awb-border-radius-top-left:0px;--awb-border-radius-top-right:0px;--awb-border-radius-bottom-right:0px;--awb-border-radius-bottom-left:0px;--awb-flex-wrap:wrap;\" ><div class=\"fusion-builder-row fusion-row fusion-flex-align-items-flex-start fusion-flex-content-wrap\" style=\"max-width:1248px;margin-left: calc(-4% \/ 2 );margin-right: calc(-4% \/ 2 );\"><div class=\"fusion-layout-column fusion_builder_column fusion-builder-column-0 fusion_builder_column_1_1 1_1 fusion-flex-column\" style=\"--awb-bg-size:cover;--awb-width-large:100%;--awb-margin-top-large:0px;--awb-spacing-right-large:1.92%;--awb-margin-bottom-large:20px;--awb-spacing-left-large:1.92%;--awb-width-medium:100%;--awb-order-medium:0;--awb-spacing-right-medium:1.92%;--awb-spacing-left-medium:1.92%;--awb-width-small:100%;--awb-order-small:0;--awb-spacing-right-small:1.92%;--awb-spacing-left-small:1.92%;\"><div class=\"fusion-column-wrapper fusion-column-has-shadow fusion-flex-justify-content-flex-start fusion-content-layout-column\"><div class=\"fusion-text fusion-text-1\"><p>REFERENCE\u00a0: Burnett TA et al. Impact of gonadotropin-releasing hormone administration at the time of artificial insemination on conception risk and its association with estrous expression. J. Dairy Sci. 2022, 105:1743\u20131753 <a href=\"https:\/\/doi.org\/10.3168\/jds.2021-20156\">https:\/\/doi.org\/10.3168\/jds.2021-20156<\/a><\/p>\n<p>TROIS FAITS<\/p>\n<ul>\n<li>50 % des \u00e9leveurs canadiens utilisent des syst\u00e8mes automatiques de d\u00e9tection des chaleurs. Se pose \u00e9nanmoins le probl\u00e8me du choix optimal du moment de l\u2019ins\u00e9mination.<\/li>\n<li>Les manifestations des chaleurs sont un gage de succ\u00e8s \u00e0 l\u2019ins\u00e9mination lors de l\u2019utilisation de programmes de synchronisation des chaleurs ou de transfert d\u2019embryons.<\/li>\n<li>L\u2019intensit\u00e9 et la dur\u00e9e de ces manifestations influencent le moment de l\u2019ovulation.<\/li>\n<\/ul>\n<p>QUELLE A ETE LEUR QUESTION ?<\/p>\n<p>L\u2019effet de l\u2019injection d\u2019une GnRH au moment de l\u2019ins\u00e9mination d\u00e9pendrait-il de l\u2019intensit\u00e9 des manifestations oestrales\u00a0?<\/p>\n<p>COMMENT ONT-ILS PROCEDE\u00a0?<\/p>\n<p>2321 IA (selon le principe AM\u00a0:PM) r\u00e9alis\u00e9es 113 \u00e0 131 jours apr\u00e8s le v\u00ealage sur 2607 \u0153strus d\u00e9tect\u00e9s au moyen de deux syst\u00e8mes automatiques (Afi Pedoplus et Rescounter II utilis\u00e9s dans trois fermes laiti\u00e8res canadiennes (11.700 \u00e0 13.200 l\/305 J).<\/p>\n<p>50 % des IA ont \u00e9t\u00e9 accompagn\u00e9es de l\u2019injection de 100 \u00b5g de gonador\u00e9line.<\/p>\n<p>Un examen \u00e9chographique ovarien a \u00e9t\u00e9 effectu\u00e9e 24\u00b14,6 h (L\u2019\u0153strus a \u00e9t\u00e9 confirm\u00e9 par l\u2019identification d\u2019un follicule dominant de &gt; 15 mm en l\u2019absence de corps jaune ou d\u2019un corps jaune de diam\u00e8tre &lt; 25 mm), 48\u00b15,2 h (L\u2019ovulation a \u00e9t\u00e9 confirm\u00e9e par l\u2019absence de follicule dominant) et 7 J (L\u2019ovulation a \u00e9t\u00e9 confirm\u00e9e par la d\u00e9tection d\u2019un corps jaune) apr\u00e8s la d\u00e9tection de l\u2019\u0153strus.<\/p>\n<p>Un constat \u00e9chographique de gestation a \u00e9t\u00e9 pos\u00e9 35\u00b17 j apr\u00e8s l\u2019IA.<\/p>\n<p>QUELLES ONT \u00c9T\u00c9 LEURS PRINCIPALES OBSERVATIONS\u00a0?<\/p>\n<p>La GnRH augmente le % de gestation\u00a0: 41.3 \u00b1 1.6 vs 35.7 \u00b1 1.7% (P = 0.02). Cette augmentation ne s\u2019observe que si les manifestations oestrales ont \u00e9t\u00e9 inf\u00e9rieures \u00e0 la valeur m\u00e9diane du nombre de pas enregistr\u00e9s\u00a0: 37.8 vs 31.0 %. Cet effet ne s\u2019observe pas si les manifestations oestrales ont \u00e9t\u00e9 sup\u00e9rieures (43.5 vs 42.6 %). Ces effets sont ind\u00e9pendants de l\u2019exploitation concern\u00e9e.<\/p>\n<p>Chez les vaches non trait\u00e9es, le % de gestation est sup\u00e9rieur quand les manifestations oestrales sont sup\u00e9rieures \u00e0 la valeur m\u00e9diane du nombre de pas enregistr\u00e9s\u00a0: 42.6 vs 31.0 %.<\/p>\n<p>Les % de gestations se sont av\u00e9r\u00e9s ind\u00e9pendants du\u00a0 num\u00e9ro de lactation, des scores corporels et de boiteries et du stade du postpartum.<\/p>\n<p>L\u2019effet favorable d\u2019une injection de GnRH ne semble pas \u00eatre m\u00e9di\u00e9 par l\u2019augmentation du % d\u2019ovulations ou le meilleur d\u00e9veloppement d\u2019un corps jaune. Il est possible que cet effet d\u00e9pende \u00e9galement de l\u2019interavlle de temps entre l\u2019injection et l\u2019ovulation mais cela est une autre histoire qui comme d\u2019habitude demandera \u00ab\u00a0a future research\u00a0\u00bb.<\/p>\n<p>MORALITE<\/p>\n<p>La majorit\u00e9 de nos \u00e9levages ne sont pas \u00e9quip\u00e9s de podom\u00e8tres. N\u00e9anmoins, il n\u2019est pas inint\u00e9ressant de renforcer l\u2019identification des trois crit\u00e8res qui rendent une vache ins\u00e9minable (tonicit\u00e9 des cornes, \u00e9coulement muqueux et diam\u00e8tre folliculaire) et de s\u2019informer des signes d\u2019\u0153strus (monte passive qui d\u00e9finit la qualit\u00e9 d\u2019un \u0153strus) pour d\u00e9cider de l\u2019injection ou non d\u2019une GnRH.<\/p>\n<\/div><div class=\"fusion-image-element \" style=\"--awb-caption-title-font-family:var(--h2_typography-font-family);--awb-caption-title-font-weight:var(--h2_typography-font-weight);--awb-caption-title-font-style:var(--h2_typography-font-style);--awb-caption-title-size:var(--h2_typography-font-size);--awb-caption-title-transform:var(--h2_typography-text-transform);--awb-caption-title-line-height:var(--h2_typography-line-height);--awb-caption-title-letter-spacing:var(--h2_typography-letter-spacing);\"><span class=\" fusion-imageframe imageframe-none imageframe-1 hover-type-none\"><img decoding=\"async\" width=\"800\" height=\"447\" title=\"Burnette 2022 GnRH at AI\" src=\"https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-scaled.jpg\" data-orig-src=\"https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-800x447.jpg\" alt class=\"lazyload img-responsive wp-image-2162\" srcset=\"data:image\/svg+xml,%3Csvg%20xmlns%3D%27http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%27%20width%3D%271900%27%20height%3D%271062%27%20viewBox%3D%270%200%201900%201062%27%3E%3Crect%20width%3D%271900%27%20height%3D%271062%27%20fill-opacity%3D%220%22%2F%3E%3C%2Fsvg%3E\" data-srcset=\"https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-200x112.jpg 200w, https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-400x224.jpg 400w, https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-600x335.jpg 600w, https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-800x447.jpg 800w, https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-1200x671.jpg 1200w, https:\/\/www.rumexperts.vet\/wp-content\/uploads\/2023\/10\/Burnette-2022-GnRH-at-AI-scaled.jpg 1900w\" data-sizes=\"auto\" data-orig-sizes=\"(max-width: 640px) 100vw, 1200px\" \/><\/span><\/div><\/div><\/div><\/div><\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":20,"featured_media":2161,"template":"","keyword":[],"theme":[59],"class_list":["post-2160","training","type-training","status-publish","has-post-thumbnail","hentry","theme-reproduction-en"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/training\/2160","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/training"}],"about":[{"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/types\/training"}],"author":[{"embeddable":true,"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/users\/20"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/media\/2161"}],"wp:attachment":[{"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/media?parent=2160"}],"wp:term":[{"taxonomy":"keyword","embeddable":true,"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/keyword?post=2160"},{"taxonomy":"theme","embeddable":true,"href":"https:\/\/www.rumexperts.vet\/en\/wp-json\/wp\/v2\/theme?post=2160"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}