Progress 12/01/03 to 11/30/07
Outputs
OUTPUTS: During the period of this progress report, the last 2 experiments of the grant were concluded and several manuscripts were published. PARTICIPANTS: Not relevant to this project. TARGET AUDIENCES: Not relevant to this project. PROJECT MODIFICATIONS: Experiment 1 In summary, feeding calcium salts enriched with linoleic acid in the peri-partum enhanced innate immune responses, whereas feeding omega-3 fatty acids during breeding suppressed inflammatory responses. Maximum fertility was observed when cows were fed omega-6 fatty acids during transition followed by omega-3 fatty acids during the breeding period. Differential immune and fertility responses to fatty acids were observed in lactating dairy cows and fat feeding strategies may serve as management tool to enhance or suppress inflammatory responses according to stage of lactation to benefit fertility of lactating dairy cows. Experiment 2 In summary, embryo quality was compromised even when the dominance of the ovulatory follicle was extended by only 1.5 days. Synchronization programs should restrict the period of ovulatory follicle dominance to 5 to 6 days to optimize embryo quality in high-producing lactating dairy cows.
Impacts
Fatty Acid and Fertility Feeding lipids that differ in fatty acid content altered postpartum immune responses and reproductive performance of dairy cows. Sequential feeding of diets enriched in linoleic acid, an omega-6 fatty acid from 30 d prepartum to 30 d postpartum, followed by diets enriched in the omega-3 fatty acids eicosapentaenoic and docosahexaenoic during the breeding period altered innate immune-responses that benefited overall cow performance and fertility. Feeding linoleic acid created a pro-inflammatory state in early lactation that can respond greatly upon challenge by increasing killing activity of neutrophils, increased pro-inflammatory cytokine production by neutrophils, and increased concentrations of acute-phase proteins in plasma. This set the stage for greater milk production. Following the transition period, initiation of supplementation with omega-3 fatty acids, which modulated immune responses by suppressing inflammation, improved fertility of dairy cows by reducing pregnancy losses. When fed a fat source rich in unsaturated fatty acids throughout the transition from late gestation to early lactation, lactating dairy cows had improved embryo quality and fertility. Reproductive Programs, Embryo Quality and Fertility Programmed management of follicle growth, regression of the corpus luteum and induction of ovulation led to development of timed insemination programs. Such manipulations of the estrous cycle to allow for fixed time insemination has become a common practice for reproductive management of lactating dairy cows. Insemination of cows following timed insemination protocols result in similar fertility when compared with insemination of cows following a synchronized estrus. Cows inseminated following synchronized ovulation have embryos of similar or better quality than cows inseminated following a synchronized estrus. Timed insemination programs based on GnRH should be initiated on estrous cycle days 5 to 9 to optimize ovulatory response to the GnRH, which reduces the period of dominance of the ovulatory follicle, improves embryo quality and increases fertility.
Publications
- Santos, J.E.P., T.R. Bilby, W.W. Thatcher, C.R. Staples, and F.T. Silvestre. 2008. Long chain fatty acids of diet as factors influencing reproduction in cattle. Reprod. Dom. Anim. 43 (Supp. 2).
- Juchem, S.O., R.L.A. Cerri, M. Villasenor, K.N. Galvao, R.G.S. Bruno, H.M. Rutigliano, E.J. DePeters, F.T. Silvestre, W.W. Thatcher, and J.E.P. Santos. 2009. Supplementation with calcium salts of linoleic and trans-octadecenoic acids improves fertility of lactating dairy cows. Reprod. Dom. Anim. In press. doi: 10.1111/j.1439 531.2008.01237.x
- Cerri, R.L.A., S.O. Juchem, R.C. Chebel, H.M. Rutigliano, R.G.S. Bruno, K.N. Galvao, W.W. Thatcher, and J.E.P. Santos. 2009. Effect of fat source differing in fatty acid profile on metabolic parameters, fertilization and embryo quality in high-producing dairy cows. J. Dairy Sci. In press. doi:10.3168/jds.2008-1614.
- Cerri, R.L.A., H.M. Rutigliano, R.C. Chebel, and J.E.P. Santos. 2009. Period of dominance of the ovulatory follicle influences embryo quality in lactating dairy cows. Reproduction In press. doi: 10.1530/REP-08-0242.
- Santos, J.E.P., H.M. Rutigliano, and M.F. Sa Filho. 2009. Risk factors for resumption of postpartum cyclicity and embryonic survival in lactating dairy cows. Anim. Reprod. 110: 207-221.
- Cerri, R.L.A., H.M. Rutigliano, R.G.S. Bruno, and J.E.P. Santos. 2009. Progesterone concentration, follicular development and induction of cyclicity in dairy cows receiving intravaginal progesterone inserts. Anim. Reprod. Sci. 110: 56-70.
- Hillegass, J., F.S. Lima, M.F. Sa Filho, and J.E.P. Santos. 2008. Effect of time of AI and supplemental estradiol on reproduction of lactating dairy cows. J. Dairy Sci. 91.
- Juchem, S.O., J.E.P. Santos, R.L.A. Cerri, R.C. Chebel, K.N. Galvao, R. Bruno, E.J. DePeters, T. Scott, W.W. Thatcher, and D. Luchini. 2008. Effect of calcium salts of fish and palm oils on lactational performance of Holstein cows. Anim. Feed Sci. Technol. 140: 18-38.
- Abstracts: Silvestre, F.T., T.S.M. Carvalho, J.E.P. Santos, C.R. Staples, and W.W. Thatcher. 2008. Effects of differential supplementation of calcium salts of fatty acids (CSFAs) on dairy cows. J. Dairy Sci. 91(E-Suppl. 1): 76-77 (Abstr.).
- Silvestre, F.T., T.S.M. Carvalho, C. Crawford, J.E.P. Santos, C.R. Staples, W.W. Thatcher. 2008. Effects of differential supplementation of calcium salts of fatty acids (CSFAs) in lactating dairy cows on plasma metabolites and leukocyte responses: phagocytic and oxidative burst, CD62L and CD18 expression and cytokine production. Soc. Study Reprod. Abstr.
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Progress 01/01/06 to 12/31/06
Outputs
Holstein cows, 495, were assigned to 3 treatments: Control (n = 167), resynchronization with a timed AI protocol upon diagnosis of nonpregnancy on d 31 after preenrollment AI (PAI); CIDRG (n = 159), use of an intravaginal progesterone insert from d 14 to 21 after AI, with AI at estrus from d 21 to 24 and initiation of a timed AI protocol on d 24 after AI in cows not reinseminated; CECPG (n = 169), same treatment as CIDRG but with an injection of 1.0 mg of estradiol cypionate at the time of progesterone insert removal. Cows were reenrolled until pregnant. Blood was collected on d 14, 21, and 24 after each AI for analysis of progesterone, and ovaries were scanned on d 21, 24 and 31 after AI. Pregnancy was presumed based on progesterone > 1.0 ng/mL on d 14, 21, and 24 after AI and diagnosed by ultrasonography on d 31 and 61 after AI. The conception rates for the PAI and all AI were similar on d 14, 21, 24, 31 and 61 after insemination. Conception rates at 31 and 61 d after
the RAI were also similar among treatments. The overall pregnancy loss for the PAI, RAI and all AI were similar for all treatments. Results indicate that the methods of resynchronization evaluated did not improve reproductive performance. Holstein cows, 1214, at 37 +/- 3 d in milk (DIM) were stratified by parity, DIM, and milk yield in the first month postpartum, and randomly assigned to: Control (n = 412), two injections of PGF2α at 37 +/- 3 and 51 +/- 3 DIM, then enrolled in a timed AI protocol 14 d later; PShort (n = 410), two injections of PGF2a at 40 +/- 3 and 54 +/- 3 DIM, then enrolled in a timed AI protocol 11 d later; PShortG (n = 392), same as PShort, but with an injection of GnRH 7 d before G1. All cows received the same time AI protocol (d 65, G1; d 72, PGF2a; d 73, 1 mg of estradiol cypionate; d 75, time AI). A subset of 1000 cows had their ovaries examined by ultrasonography at G1 and 7 d later when PGF2a of the timed AI was given to determine presence of corpus
luteum (CL) and ovulation to G1. Pregnancy was diagnosed on d 38 after timed AI, and pregnant cows were re-evaluated for pregnancy 4 weeks later. Presence of a CL at G1 was not influenced by interval between presynchronization and initiation of timed AI, but GnRH increased the proportion of cows with CL. Ovulation to G1 was greater for 11 compared with the 14 d interval, but GnRH did not improve ovulation. The increased ovulation to G1 when the interval was reduced from 14 to 11 d was caused primarily by greater ovulatory response in cows with a CL at G1, but treatment did not affect ovulation in cows without a CL at G1. Treatment affected the conception rates on d 38 and 66 after timed AI, and they were greater for the 11 compared with 14 d interval, but addition of GnRH did not improve conception rates. Cows ovulating to G1 had greater conception rates regardless if they had or not a CL at G1. Shortening the interval from presynchronization to initiation of timed AI protocol from 14
to 11 d increased ovulatory response to the first GnRH of the synchronization of ovulation protocol and conception rates to first insemination.
Impacts
Resynchronization of cows: Synchronization of estrus and ovulation are widely used in lactating dairy cows to shorten inter-insemination interval. This was a unique study in which 3 reproductive programs were tested during a 10 month period to determine not only the effect on a single insemination, but over time to mimic what would happen if such programs were to be implemented for reproductive management in commercial farms. Resynchronization with intravaginal progesterone insert and injection of GnRH 7 d prior to pregnancy diagnosis reduced detection of estrus up to pregnancy diagnosis, but incorporation of an injection of estradiol cypionate at insert removal reestablished estrous detection and reduced inter-AI interval. Nevertheless, method of resynchronization did not influence conception rates and time to pregnancy in dairy cows. Optimization of timed AI protocol: Protocols for synchronization of ovulation are commonly used in reproductive management of lactating
dairy cows. Reproductive responses to these protocols are improved when cows are presynchronized with prostaglandin F2α to initiate the timed insemination program during early to mid diestrus. When the interval between the final prostaglandin F2α of the presynchronization protocol was reduced from 14 to 11 d, ovulatory response to gonadotropin-releasing hormone and conception rates were improved. Our results indicate that a simple change in interval from presynchronization to initiation of the timed insemination protocol can result in improvements in pregnancy of 7% points, which represents 20%.
Publications
- Juchem, S.O., J.E.P. Santos, R.L.A. Cerri, R.C. Chebel, K.N. Galvao, R. Bruno, E.J. DePeters, T. Scott, W.W. Thatcher, and D. Luchini. 2007. Effect of calcium salts of fish and palm oils on lactational performance of Holstein cows. Anim. Feed Sci. Technol. In Press (Accepted January 2007).
- Chebel, R.C., J.E.P. Santos, R.L.A. Cerri, H.M. Rutigliano, and R.G.S. Bruno. 2006. Reproduction in dairy cows following progesterone insert presynchronization and resynchronization protocols. J. Dairy Sci. 89: 4205-4219.
- Thatcher, W.W., and J.E.P. Santos. 2007. Control of ovarian follicular and corpus luteum development for the synchronization of ovulation in cattle. Reproduction Supplement In press.
- Thatcher, W.W., F. Silvestre, C.A. Risco, J.E.P. Santos, and C.R. Staples. 2006. Improving pregnancy maintenance in dairy cows. J. Reprod. Dev. 52: S121-S130.
- Abstracts: Juchem, S.O., J.M. Heguy, E.J. DePeters, J.E.P. Santos, M. Rosenberg, and S.J. Taylor. 2006. Effect of feeding soybean and linseed oils as whey protein gel composites, calcium salts or free oil on rumen fermentation, digestibility and duodenal ow of fatty acids. J. Dairy Sci. 89(Suppl. 1): 143 (Abstr.).
- Rutigliano, H.M., F.S. Lima, R.L.A. Cerri, L.F. Greco, J.M. Vilela, V. Magalhaes, J. Hillegass, W.W. Thatcher, and J.E.P. Santos. 2006. Effects of source of supplemental Se and method of presynchronization on reproduction and lactation of dairy cows. J. Dairy Sci. 89(Suppl. 1): 151 (Abstr.).
- Galvao, K.N. M.F. Sa Filho, and J.E.P. Santos. 2007. Reducing the interval from presynchronization to initiation of timed AI improves fertility in dairy cows. J. Dairy Sci. (Submitted March 2007)
- Santos, J.E.P., H.M. Rutigliano, and M.F. Sa Filho. 2006. Factors influencing resumption of postpartum cyclicity and embryonic survival in lactating dairy cows. Anim. Reprod. Sci. (submitted December 2006).
- Galvao, K.N. J.E.P. Santos, R.L. Cerri, R.C. Chebel, H.M. Rutigliano, R.G. Bruno, and R. C. Bicalho. 2007. Effect of methods of resynchronization of lactating cows of unknown pregnancy status on reproductive performance. J. Dairy Sci. in press (Accepted March 2007).
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Progress 01/01/05 to 12/31/05
Outputs
A total of 511 Holstein cows were assigned prepartum to receive either Ca salts of palm oil or Ca salts of linoleic and trans fatty acids. Cows were fed the diets from 21 d prepartum to 70 d postpartum and lactation, health and reproduction was monitored. Feeding Ca salts of linoleic and trans fatty acids altered milk composition, resulted in similar yield of milk and did not alter hepatic and blood composition. Conception rate on day 41 (33.5 vs 25.6%) after AI was greater (P = 0.09) for cows fed linoleic and trans fatty acids. Holstein cows, 6,123 in 5 dairy farms were evaluated to determine factors affecting cyclicity and embryonic survival at the first postpartum AI in dairy cows. Cyclicity was influenced (P < 0.001) by parity BCS, milking frequency and milk yield. More cyclic than anovular cows were pregnant at 30 (40.1 vs 28.1%; P<0.001) and 58 (34.3 vs 22.0%; P<0.001) days after AI, and anovulation increased pregnancy loss (14.4 vs 18.7%; P=0.10). Pregnancy
loss was highest (21.9 vs 16.6 vs 12.1%; P<0.01) and pregnancy rate at d 58 lowest (22.3 vs 30.7 vs 35.6%; P<0.01) in cows that lost > 1 unit of BCS than those that lost <1 or experienced no change in BCS from calving to AI. Likewise, a higher BCS at AI (> 3.75 vs 3.0 to 3.5 vs < 2.75) increased (P<0.01) pregnancy rate at 58 (41.8 vs 35.1 vs 28.5%) d after AI. Minimizing losses of BCS after calving and improving cyclicity early postpartum are expected to increase pregnancy rate because of enhanced embryonic survival. A possible method to induce cyclicity in anovular dairy cows is the use of intravaginal progesterone inserts (IPI). Plasma progesterone concentrations increased from 0.18 to 0.78 ng/mL in the first 15 min after IPI insertion, but achieved a plateau (0.9 ng/mL) at 90 min. After removal of IPI, progesterone decreased to basal concentrations by 90 min. During d 1 to 7, only 18% of the samples were greater than 1 ng/mL. Intravaginal progesterone insert resulted in mostly
subluteal (<1 ng/mL) progesterone concentrations in lactating dairy cows. In a subsequent study, when the IPI was used to expose cows to progesterone prior to first postpartum insemination with 1019 Holstein cows, it improved induction of cyclicity in anovular cows, but did not influence pregnancy rates or embryonic survival. When used for resynchronization, between days 14 and 21 after AI, the IPI increased pregnancy rate because of reduced pregnancy loss (14.8 vs. 24.7%; P < 0.05). In a subsequent experiment, when the IPI was utilized prior to enrollment in a timed AI protocol in cows not displaying signs of estrus (n = 898) it improved pregnancy rates in primiparous (52.7 vs 41.6%), but not in multiparous cows.
Impacts
Fatty Acid and Fertility: Feeding lipids that differ in fatty acid content altered reproductive performance of dairy cows because of changes in fertilization and embryo quality. Methods to protect lipids from rumen biohydrogenation might prove useful to improve fertility in dairy cows. Anestrus/Anovular Cows and Supplemental Progesterone: Many risk factors were identified for extended interval from calving to first postpartum ovulation in lactating dairy cows, among them were parity (primiparous > multiparous), milking frequency (3 times daily > twice daily), losses of body condition or low body condition score at 60 to 70 d postpartum, and lack of postpartum cyclicity prior to first insemination resulted in lower conception rates and increased pregnancy loss. One of the characteristics of anovular/anestrous cows is lack of exposure to progesterone prior to insemination. To overcome that, an intravaginal insert containing progesterone was evaluated in lactating dairy
cows. Concentrations of progesterone in plasma were mostly subluteal, indicating that the insert does not deliver adequate amounts of progesterone to maintain high concentrations in lactating dairy cows. In spite of that, the insert was capable of increasing induction of cyclicity postpartum, and improved pregnancy rates either because of increased conception or embryonic survival in lactating dairy cows when utilized prior to first postpartum AI or 14 days after insemination.
Publications
- Bruno, R.G.S., H.M. Rutigliano, R.L.A. Cerri, and J.E.P. Santos. 2005. Effect of addition of a CIDR insert prior to a timed AI protocol on pregnancy rates and pregnancy losses in dairy cows. J. Dairy Sci. 88(Suppl. 1): 87 (Abstr.).
- Cerri, R.L.A., H.M. Rutigliano, R.G.S. Bruno, and J.E.P. Santos. 2005. Progesterone (P4) concentrations and ovarian response after insertion of a new or a 7 d used intravaginal P4 insert (IPI) in proestrus lactating cows. J. Dairy Sci. 88(Suppl. 1): 37 (Abstr.).
- Galvao, K.N., R.L.A. Cerri, H.M. Rutigliano, R.G.S. Bruno, R.C. Chebel, and J.E.P. Santos. 2005. Resynchronizing estrus with a progesterone (P4) insert and estradiol cypionate (ECP) in cows of unknown pregnancy status. J. Dairy Sci. 88(Suppl. 1): 85 (Abstr.).
- Rutigliano, H.M., and J.E.P. Santos. 2005. Interrelationships among parity, body condition score (BCS), milk yield, AI protocol, and cyclicity with embryonic survival in lactating dairy cows. J. Dairy Sci. 88(Suppl. 1): 39 (Abstr.).
- Thatcher, W.W., T.R. Bilby, J.A. Bartolome, F. Silvestre, C.R. Staples, and J.E.P. Santos. 2006. Strategies for improving fertility in the modern dairy cow. Theriogenology 65: 30-44.
- Juchem, S.O., J.E.P. Santos, R.L.A. Cerri, R.C. Chebel, K.N. Galvao, R. Bruno, E.J. DePeters, T. Scott, W.W. Thatcher, and D. Luchini. 2006. Effect of calcium salts of fish and palm oils on lactational performance of Holstein cows. J. Dairy Sci. (Submitted November 2005).
- Thatcher, W.W., T.R. Bilby, L. MacLaren, C.R. Staples, and J.E.P. Santos. 2005. Effects of omega-3 and omega-6 fatty acids on reproduction in dairy cattle. Biology of Reproduction Mini Symposium. In Annual Meeting of the Society for Study of Reproduction, July 24 to 28, Quebec City, Canada.
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Progress 01/01/04 to 12/31/04
Outputs
Lactating Holstein cows from 3 herds were inseminated after a timed artificial insemination (AI) using 1 mg of estradiol cypionate (ECP) to induce ovulation or after being observed in estrus (Cerri et al., 2004). Conception rates and pregnancy rates were higher for cows in the timed AI group than in the estrus-detected group at 30, 44, and 58 d of gestation. Pregnancy losses were 11.5% from 30 d to 58 d and did not differ between treatments. Cyclic cows had higher estrous responses, conception rates, and pregnancy rates. Use of 1 mg of ECP to induce ovulation as part of a synchrony regimen improved reproduction at first postpartum insemination in dairy cows. In a second experiment (Galvao et al., 2004) we evaluated the effects of adding a progesterone intravaginal insert (CIDR) during a timed AI protocol using ECP to synchronize ovulation on ovarian responses and pregnancy in lactating cows. Cows receiving a CIDR had similar rates of detected estrus, ovulation, and
pregnancy at 27 and 41 d after AI, and late embryonic loss by 41 d after AI compared to control cows. Cyclic cows had greater pregnancy rates than anovulatory after AI (33.8 vs 20.4%) because of reduced late embryonic loss (16.0 vs 30.3%). Pregnancy rates were greater for cows displaying estrus, which were related to the greater ovulation rate and reduced late embryonic loss. Incorporation of a CIDR insert into a timed AI protocol utilizing ECP to induce ovulation did not improve pregnancy rates in lactating dairy cows. Improvements in pregnancy rates in cows treated with ECP in a timed AI protocol are expected when more cows display estrus, thereby increasing ovulation rate. In a third experiment (Bruno et al., 2004), cows under heat stress were fed 400 g of fatty acids from as a Ca salts of palm and fish oil (CaPFO) or tallow. Lactation performance was not affected by fat source. Conception rates for cows fed CaPFO and tallow were similar at d 38 (26.9 vs 25.9%) and 60 (24.1 vs
24.5%) after AI, as well as pregnancy loss from d 38 to 60 of gestation (9.7 vs 4%). These results suggest that feeding CaPFO do not influence lactation or reproduction of cows under heat stress. In a fourth experiment (Juchem et al., 2004a; 2004b), cows received 2% of the diet as Ca salts of palm oil (PO) or linoleic and monoenoic trans fatty acids (LTFA). Yields of milk were similar, but feeding LTFA reduced 3.5% fat-corrected milk (36.8 vs 39.1 kg/d) because of lower milk fat % (3.3 vs 3.6%). Feeding LTFA increased the concentrations of linoleic acid (3.56 vs 2.83%), C18:1 trans 10 (1.0 vs 0.4 %), and conjugated linoleic acid (0.8 vs 0.5%) in milk fat. Diet did not affect hepatic concentrations of triacylglycerol and glycogen, incidence of clinical diseases, and plasma concentrations of glucose, nonesterified fatty acids and 3-hidroxibutirate. Fat source did not affect plasma concentrations of prostaglandin F metabolite and uterine involution, but increased pregnancy rate (36 vs
28%) at first AI. These results suggest that feeding a fat source rich in linoleic and trans fatty acids improve fertility of dairy cows and the effect is not mediated by changes in metabolism or uterine health.
Impacts
The results of the first two experiments indicate use of 1 mg of estradiol cypionate to induce ovulation as part of a synchrony regimen improved reproduction at first postpartum insemination in dairy cows. However, incorportion of a progesterone intravaginal insert to a timed AI using estradiol cypionate to induce ovulation did not improve pregnancy rates in lactating dairy cows in spite of cyclic status. Our findings suggest that improvements in pregnancy rates in cows treated with estradiol cypionate to induce ovulation in a timed insemination protocol are expected when more cows display estrus, thereby increasing ovulation rate. The results of the experiments with feeding lipids with different fatty acid composition indicated that feeding Ca salts of palm and fish oil did not improve pregnancy rates or embryonic survival in lactating dairy cows exposed to heat stress. However, feeding a fat source rich in linoleic and monoenoic trans fatty acids during late
gestation and early lactation improved conception rates in lactating dairy cows when compared with a more saturated fatty acid source. Improvements in fertility caused by linoleic and trans fatty acids were not the result of improvements in lipid metabolism or uterine health in dairy cows, but likely due to increased oocyte quality, fertilization rate and embryo quality.
Publications
- Cerri, R.L.A., J.E.P. Santos, S.O. Juchem, K.N. Galvao, R.C. Chebel. 2004. Timed artificial insemination with estradiol cypionate or insemination at estrus in high-producing dairy cows. J. Dairy Sci. 87: 3704-3715.
- Galvao, K.N., J.E.P., Santos, S.O. Juchem, R.L.A. Cerri, A.C. Coscioni, and M. Villasenor. 2004. Effect of addition of a progesterone intravaginal insert to a timed insemination protocol using estradiol cypionate on ovulation rate, pregnancy rate, and late embryonic loss in lactating dairy cows. J. Anim. Sci. 82: 3508-3517.
- Santos, J.E.P., W.W. Thatcher, R.C. Chebel, R.L.A. Cerri, and K.N. Galvao. 2004. The effect of embryonic death rates in cattle on the efficacy of estrous synchronization programs. Anim. Reprod. Sci. 82-83C: 513-535.
- Juchem, S.O., R.L.A. Cerri, M. Villasenor, K.N. Galvao, R. Bruno, H.M. Rutigliano, A.C. Coscioni, E.J. DePeters, W.W. Thatcher, D. Luchini, and J.E.P. Santos. 2004a. Effect of feeding Ca salts of palm oil (PO) or of a blend of linoleic and monoenoic trans fatty acids (LTFA) on lactation and health of Holstein ocws. J. Dairy Sci. 87(Suppl. 1): 95-96 (Abstr.).
- Juchem, S.O., R.L.A. Cerri, R. Bruno, K.N. Galvao, E.W. Lemos, M. Villasenor, A.C. Coscioni, H.M. Rutigliano, W.W. Thatcher, D. Luchini, and J.E.P. Santos. 2004b. Effect of feeding Ca salts of palm oil (PO) or of a blend of linoleic and monoenoic trans fatty acids (LTFA) on uterine involution and reproductive performance in Holstein cows. J. Dairy Sci. 87(Suppl. 1): 310 (Abstr.).
- Bruno, R.G.W., K.N. Galvao, S.O. Juchem, W.W. Thatcher, E.J. DePeters, D. Luchini, and J.E.P. Santos. 2004. Effect of Ca salts of palm and fish oils on lactation and reproduction of dairy cows under heat stress. J. Dairy Sci. 87(Suppl. 1): 336 (Abstr.).
- Galvao, K.N., S.O. Juchem, R.L.A. Cerri, A.C. Coscioni, M. Villasenor, and J.E.P. Santos. 2004. Effect of addition of a CIDR insert to the Heatsynch protocol on ovulation rate, pregnancy rate and pregnancy loss in lactating dairy cows. J. Dairy Sci. 87(Suppl. 1): 372 (Abstr.).
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Progress 01/01/03 to 12/31/03
Outputs
Grant has recently been awarded (December of 2003) and experiment 1 of the grant has been initiated. Objective of experiment 1 was to determine the effects of feeding a rumen-protected source of linoleic and trans fatty acids during the transition period on uterine secretion of PGF2α, uterine involution and incidence of endometritis, health, and lactational and reproductive performance. A total of 430 Holstein dairy cows were assigned prepartum to one of the two treatment diets that differed in the source of supplemental fatty acids (Ca salts of palm oil vs Ca salts of linoleic and trans fatty acids). Cows are being fed the diets from 21 d prepartum to 50 d postpartum and lactation, health and reproduction has been monitored. Preliminary data from 308 cows indicate that feeding Ca salts of linoleic and trans fatty acids increased conception rates at first AI (38.9 vs 26.0; P = 0.02) As part of experiment 1, an additional objective of this project is to determine
the effects of feeding a rumen-protected source of linoleic and trans fatty acids during the transition period on fertilization rate and embryo quality. A total of 154 lactating Holstein dairy cows were assigned prepartum to one of the two treatment diets that differed in the source of supplemental fatty acids (Ca salts of palm oil vs Ca salts of linoleic and trans fatty acids). Cows were fed the diets from 21 d prepartum to 60 d postpartum and ultrasound evaluation of ovaries was performed weekly to determine resumption of luteal function. Ovulation was synchronized and cows were inseminated following the Ovysnch protocol at 50 d postpartum. Semen of two ejaculates from a single sire was utilized and all cows were inseminated by the same technician. Cows were flushed on day 5 after AI and structures recovered were evaluated. A total of 45 and 41 structures were collected from cows fed Ca salts of palm oil (54.9% recovery) and Ca salts of linoleic and trans fatty acids (51.9%
recovery), respectively. Fertilization rate tended (P = 0.11) to be higher for cows fed Ca salts of linoleic and trans fatty acids compared to cows fed Ca salts of palm oil (87.2 vs 73.3%). Number of accessory spem attached to the structures was greater for cows fed Ca salts of linoleic and trans fatty acids compared to cows fed Ca salts of palm oil (34.3 vs 21.5; P < 0.001). Similarly, the proportion of fertilized structures classified as grade quality 1 and 2 (high and good quality) was higher for cows fed Ca salts of linoleic and trans fatty acids compared to cows fed Ca salts of palm oil (73.5 vs 51.5%; P = 0.06). Total number of cells (19.4 vs 14.0; P = 0.13) and proportion of live cells (94.2 vs 85.3%; P = 0.09) in fertilized structures tended to be higher for fed Ca salts of linoleic and trans fatty acids compared to cows fed Ca salts of palm oil. In summary, feeding Ca salts of linoleic and trans fatty acids during the transition period improved fertilization rate and embryo
quality in lactating dairy cows.
Impacts
The results of the first experiment of this project indicate that manipulating the fatty acid profile of the diet impacts concepiton rates of dairy cows and the increased conception is associated partly with increased fertilization rate and embryo quality.
Publications
- Cerri, R.L.A., R. Bruno, R.C. Chebel, K.N. Galvao, W.W. Thatcher, E.J. DePeters, D. Luchini, and J.E.P. Santos. 2004. Effect of fat sources differing in fatty acid profile on fertilization rate and embryo quality in lactating dairy cows. J. Dairy Sci. 87(Suppl. 1): ?.(Abstr.).
- Juchem, S.O., R.L.A. Cerri, R. Bruno, K.N. Galvao, R.C. Chebel, W.W. Thatcher, E.J. DePeters, D. Luchini, and J.E.P. Santos. 2004a. Effect of feeding Ca salts rich in w-6 and trans fatty acids during transition on lactational performance of dairy cows. J. Dairy Sci. 87(Suppl. 1): ?.(Abstr.).
- Juchem, S.O., R.L.A. Cerri, R. Bruno, K.N. Galvao, R.C. Chebel, W.W. Thatcher, E.J. DePeters, D. Luchini, and J.E.P. Santos. 2004b. Effect of feeding Ca salts rich in w-6 and trans fatty acids during transition on reproduction and health of dairy cows. J. Dairy Sci. 87(Suppl. 1): ?.(Abstr.).
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