TY - CONF
T1 - Superovulatory response and embryo quality in beef cattle grazing lucerne
AU - Nevard, Rory
AU - Loy, Jaymie
AU - Gurusinghe, Saliya
AU - McCormick, Jeff
AU - Weston, Leslie
AU - Stephen, Cyril
A2 - Wyse, Jessica
PY - 2023
Y1 - 2023
N2 - Livestock with access to pastures with high phyto-oestrogen concentrations may experience compromised reproductive functions.1. This study was conducted to investigate the impact of phytooestrogens on superovulatory response and embryo quality in cattle grazing lucerne.
An eight-week grazing trial was conducted using 20 pluriparous Angus cows on lucerne and ryegrass pastures. Cows were subjected to an oestrus synchronisation programme using CIDR, oestradiol
benzoate and cloprostenol as previously described2
. Four days following CIDR insertion, FSH (Folltropin
V, 20 mg/mL) was injected twice daily (q12 hrs x 4 days), in a tapering dose, to superstimulate follicles.
On the last day of FSH injections, CIDR’s were removed and cloprostenol (500 μg) was injected twice
(q12 hrs). Gonadorelin (250 μg) was administered 24 hrs after removing the CIDR’s, and the cows were
artificially inseminated with frozen semen (AM and PM) from a proven sire the following day. Embryo
recovery and grading occurred seven days post insemination. Blood and pasture samples were collected
every seven days to measure phyto-oestrogens3
. Metabolomic profiling of pasture and plasma samples
was performed using HPLC-MS-QTOF and HPLC-MS-QQQ.
Numerous phyto-oestrogens including, coumestrol, were found in both the plasma and pasture
samples. Significant embryo quality differences were noted between cattle grazing lucerne for eight
weeks and the control group. There was no effect on superovulatory response in both groups.
Our findings suggest that phyto-oestrogens, although not directly influencing the superovulatory
response, can influence the embryo quality in cattle grazing lucerne for greater than three weeks,
particularly where concentrations exceed 25 mg/kg DM.
References:
1. Borzym E, Bobowiec R, Kosior-Korzecka U, Martelli F, Burmaczuk A. Disturbances of cow oocyte
maturation by phytoestrogens. Med. Weter. 2008;64:1107–1111.
2. Bó GA, Mapletoft RJ. Historical perspectives and recent research on superovulation in cattle.
Theriogenology. 2014 Jan 1;81(1):38-48.
3. Wyse J, Latif S, Gurusinghe S, Berntsen ED, Weston LA, Stephen C. Characterization of
phytoestrogens in Medicago sativa L. and grazing beef cattle. Metabolites. 2021;11
AB - Livestock with access to pastures with high phyto-oestrogen concentrations may experience compromised reproductive functions.1. This study was conducted to investigate the impact of phytooestrogens on superovulatory response and embryo quality in cattle grazing lucerne.
An eight-week grazing trial was conducted using 20 pluriparous Angus cows on lucerne and ryegrass pastures. Cows were subjected to an oestrus synchronisation programme using CIDR, oestradiol
benzoate and cloprostenol as previously described2
. Four days following CIDR insertion, FSH (Folltropin
V, 20 mg/mL) was injected twice daily (q12 hrs x 4 days), in a tapering dose, to superstimulate follicles.
On the last day of FSH injections, CIDR’s were removed and cloprostenol (500 μg) was injected twice
(q12 hrs). Gonadorelin (250 μg) was administered 24 hrs after removing the CIDR’s, and the cows were
artificially inseminated with frozen semen (AM and PM) from a proven sire the following day. Embryo
recovery and grading occurred seven days post insemination. Blood and pasture samples were collected
every seven days to measure phyto-oestrogens3
. Metabolomic profiling of pasture and plasma samples
was performed using HPLC-MS-QTOF and HPLC-MS-QQQ.
Numerous phyto-oestrogens including, coumestrol, were found in both the plasma and pasture
samples. Significant embryo quality differences were noted between cattle grazing lucerne for eight
weeks and the control group. There was no effect on superovulatory response in both groups.
Our findings suggest that phyto-oestrogens, although not directly influencing the superovulatory
response, can influence the embryo quality in cattle grazing lucerne for greater than three weeks,
particularly where concentrations exceed 25 mg/kg DM.
References:
1. Borzym E, Bobowiec R, Kosior-Korzecka U, Martelli F, Burmaczuk A. Disturbances of cow oocyte
maturation by phytoestrogens. Med. Weter. 2008;64:1107–1111.
2. Bó GA, Mapletoft RJ. Historical perspectives and recent research on superovulation in cattle.
Theriogenology. 2014 Jan 1;81(1):38-48.
3. Wyse J, Latif S, Gurusinghe S, Berntsen ED, Weston LA, Stephen C. Characterization of
phytoestrogens in Medicago sativa L. and grazing beef cattle. Metabolites. 2021;11
KW - Phytoestrogens
KW - Bovine reproduction
M3 - Abstract
T2 - ANZCVS Science Week 2023
Y2 - 27 July 2023 through 29 July 2023
ER -