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Post-AI Supplementation with Ca Salts of Soybean Oil Increases Pregnancy Success in Bos taurus BeefCows
Post-AI Supplementation with Ca Salts of Soybean Oil Increases Pregnancy Success in Bos taurus BeefCows
Wednesday, March 14, 2018: 9:35 AM
210/211 (CenturyLink Convention Center)
Two experiments investigated the effects of supplementing Ca salts of soybean oil (CSSO) during early
gestation on reproductive function and pregnancy rates to timed-AI in B. taurus beef cows. In Exp. 1, 771
lactating multiparous Angus cows were divided into 22 groups of approximately 35 cows/group, and
timed-AI on d 0. After AI, groups were randomly assigned to receive (as-fed basis) 200 g/cow daily of a
corn-based supplement and: 1) 100 g/cow daily of CSSO (n = 11; Essentiom; Church and Dwight Co.,
Inc., Princeton, NJ) or 2) 100 g/cow daily of prilled SFA (CON, n = 11; EnergyBooster; Milk Specialties,
Eden Prairie, MN). Groups were maintained in individual pastures with free-choice access to forage, and
offered treatments from d 0 to 21. Pregnancy status was determined on d 30 via transrectal
ultrasonography. Cows receiving CSSO had greater (P = 0.01) pregnancy rates to timed-AI compared
with CON cows (60.2 vs. 51.7%; SEM = 4.2). In Exp. 2, 90 lactating multiparous Angus cows housed in
18 drylot pens (5 cows/pen) were assigned to the same timed-AI program and treatments from Exp. 1 (9
pens/treatment), receiving 20 kg/d (DM basis) of grass-alfalfa hay. Transrectal ultrasonography was
performed to verify ovulation and corpus luteum (CL) volume immediately prior to AI, d 7, and 15.
Within each treatment, 22 cows diagnosed without the presence of a CL on d 0, but with a CL greater
than 0.38 cm 3 on d 7 and 15, were assigned to conceptus collection via transcervical flushing with saline
followed by endometrial biopsy on d 15. Both procedures were performed in the uterine horn ipsilateral to
the CL. Blood samples were collected for whole blood RNA extraction (d 20) and pregnancy diagnosis (d
30; BioPRYN; Gold Standard Labs, Bowling Green, KY). Conceptus from cows receiving CSSO had
greater (P ≤ 0.05) mRNA expression of interferon-tau vs. conceptus from CON cows (21.3 vs. 12.1 fold
effect; SEM = 3.4). Within cows diagnosed as pregnant on d 30, blood mRNA expression of interferon-
stimulated gene 15 and 20,50-oligoadenylate synthetase on d 20 were greater in CSSO vs. CON cows
(43.1 vs. 29.8 fold effect, SEM = 4.6; 26.8 vs. 18.3 fold effect, SEM = 2.7; respectively). Hence, post-AI
CSSO supplementation to beef cows increased pregnancy rates to timed-AI compared with non-
supplemented cows, which can be attributed to increased mRNA expression of interferon-tau by the
conceptus when CSSO is supplemented during early gestation.
gestation on reproductive function and pregnancy rates to timed-AI in B. taurus beef cows. In Exp. 1, 771
lactating multiparous Angus cows were divided into 22 groups of approximately 35 cows/group, and
timed-AI on d 0. After AI, groups were randomly assigned to receive (as-fed basis) 200 g/cow daily of a
corn-based supplement and: 1) 100 g/cow daily of CSSO (n = 11; Essentiom; Church and Dwight Co.,
Inc., Princeton, NJ) or 2) 100 g/cow daily of prilled SFA (CON, n = 11; EnergyBooster; Milk Specialties,
Eden Prairie, MN). Groups were maintained in individual pastures with free-choice access to forage, and
offered treatments from d 0 to 21. Pregnancy status was determined on d 30 via transrectal
ultrasonography. Cows receiving CSSO had greater (P = 0.01) pregnancy rates to timed-AI compared
with CON cows (60.2 vs. 51.7%; SEM = 4.2). In Exp. 2, 90 lactating multiparous Angus cows housed in
18 drylot pens (5 cows/pen) were assigned to the same timed-AI program and treatments from Exp. 1 (9
pens/treatment), receiving 20 kg/d (DM basis) of grass-alfalfa hay. Transrectal ultrasonography was
performed to verify ovulation and corpus luteum (CL) volume immediately prior to AI, d 7, and 15.
Within each treatment, 22 cows diagnosed without the presence of a CL on d 0, but with a CL greater
than 0.38 cm 3 on d 7 and 15, were assigned to conceptus collection via transcervical flushing with saline
followed by endometrial biopsy on d 15. Both procedures were performed in the uterine horn ipsilateral to
the CL. Blood samples were collected for whole blood RNA extraction (d 20) and pregnancy diagnosis (d
30; BioPRYN; Gold Standard Labs, Bowling Green, KY). Conceptus from cows receiving CSSO had
greater (P ≤ 0.05) mRNA expression of interferon-tau vs. conceptus from CON cows (21.3 vs. 12.1 fold
effect; SEM = 3.4). Within cows diagnosed as pregnant on d 30, blood mRNA expression of interferon-
stimulated gene 15 and 20,50-oligoadenylate synthetase on d 20 were greater in CSSO vs. CON cows
(43.1 vs. 29.8 fold effect, SEM = 4.6; 26.8 vs. 18.3 fold effect, SEM = 2.7; respectively). Hence, post-AI
CSSO supplementation to beef cows increased pregnancy rates to timed-AI compared with non-
supplemented cows, which can be attributed to increased mRNA expression of interferon-tau by the
conceptus when CSSO is supplemented during early gestation.