Submitted to: International Symposium on Reproduction in Domestic Ruminants
Publication Type: Abstract Only
Publication Acceptance Date: 4/6/2006
Publication Date: 8/13/2006
Citation: Geary, T.W., Macneil, M.D., Ansotegui, R.P. 2006. Effects of transportation stress, handling stress and flunixin meglumine approximately 13 d after AI on pregnancy establishment. Proceedings of the Seventh International Symposium on Reproduction in Domestic Ruminants, Wellington, New Zealand, August 2006:527. Interpretive Summary:
Technical Abstract: Embryonic mortality in cattle represents a significant loss to the beef and dairy industries. Transportation of cattle at critical times after AI has been reported to decrease pregnancy rates, presumably through increased embryonic loss. Our objective was to determine effects of transportation or handling stress with or without a single injection of the prostaglandin inhibitor Flunixin Meglumine (FM; 1.1 mg/kg BW, i.m.) ~13 d after AI on pregnancy establishment. Four experiments were conducted using estrus-synchronized heifers (n = 1,725) and cows (n = 1,278). Technicians and AI sires were equally represented across treatments within locations and experiments. Bulls were introduced following treatment. Pregnancy was diagnosed 28 to 50 d after AI using ultrasonography. In Exp 1, suckled beef cows (n = 224) within two locations and beef heifers (n = 259) at one location were divided within location to receive 4 h transportation stress (TS), TS + FM (TSFM), control (CON) or CON + FM (CONFM) treatment. The CONFM treatment was omitted at one cow location due to insufficient numbers (n = 97). Analyses of data for cows and heifers in Exp 1 that received TS, TSFM, and CON treatments revealed a tendency for TSFM females (74%) to have higher (P < 0.07) AI pregnancy rates than TS (64%) or TS + CON females combined (66%). Analyses of data from the two locations at which cows and heifers received TS, TSFM, CON, or CONFM treatments as a 2x2 factorial revealed higher (P = 0.05) AI pregnancy rates among FM treated cows and heifers (71%) compared to non-FM females (61%). The AI pregnancy rates of TS (59%), CON (64%), TSFM (70%), and CONFM (73%) were not different (P > 0.10). Serum collected from females at 0, 2 and 4 h after treatment onset revealed decreased prostaglandin F metabolite for FM compared to non-FM females and increased cortisol for TS compared to non-TS females at the 2 and 4 h blood samplings. In Exp 2, beef heifers (n = 1,219) were divided within five locations to receive FM or no further treatment (Control). At insemination, heifers were divided into two similar pastures or pens and ~ 13 d later, one group of heifers within each location was worked through an animal handling facility to administer FM treatment. There was no location by treatment interaction (P > 0.10) on AI pregnancy rates, so data were pooled. Pregnancy rates to AI were reduced (P < 0.025) among heifers receiving FM (66%) compared to control heifers (72%). In Exp 3, suckled beef cows (n = 719) were assigned within two locations to receive FM or no further treatment (Control) ~13 d after AI. At insemination, Control and FM cows were divided into separate pastures and only FM cows were handled after AI. There was no location by treatment interaction (P > 0.10) so data were pooled. Pregnancy rates to AI did not differ (P > 0.10) between FM (57%) and Control cows (59%). In Exp 4, beef heifers (n = 247) and suckled beef cows (n = 335) from one location were assigned at AI to receive FM or Control treatment ~13 d later. In Exp. 4, all cows and heifers were handled through a working facility but only half of each age group received FM treatment. Pregnancy rates to AI between FM (45%) and Control cows (42%) or FM (56%) and control (55%) heifers were not different (P > 0.10). We conclude that transportation and handling stress ~13 d after AI decreases pregnancy establishment and that this decrease may be related to the degree of stress perceived. Administration of FM (1.1 mg/kg BW) ~13 d after AI minimized the loss, but did not improve pregnancy establishment in beef cows and heifers.