330 Effect of inducing high or low progesterone concentrations during ovulatory follicle development on double ovulation and fertility of lactating dairy cows

Background: Beta-(β-) carotene, is the precursor to vitamin A, in particular, has some potential benefits on reproduction. The main objective of this study was to investigate the efficacy of β-carotene administration on fertility following either prostaglandin F2 alpha (PGF) induced estrus or Ovsynch protocol in lactating dairy cows.Methods: Cows with at 47±3 postpartum days were divided into two groups: β-carotene group (βC, n=139) was treated with injectable β-carotene while untreated cows served as control (CON, n=227). In both groups, PGF was administered and heatmount detectors were applied at 54±3 days postpartum. Cows detected in estrus after PGF were inseminated. Cows that had not been detected in estrus were divided into two groups 7 days after PGF administration; βC-OVS (n=137) and CON-OVS (n=89). Ovsynch protocol was initiated 4 days after β-carotene administration.Result: The estrus detection rate was similar between the βC and CON groups (P = 0.19). Pregnancy per AI (P/AI) on d 31 was also similar between groups (P = 0.93). In the Ovsynch protocol, ovulation to the first GnRH and ovulatory follicle diameter at the time of insemination did not differ between groups. No difference was observed in P/AI at d 31 (P = 0.13). The results of this study indicated that β-carotene administration had no effect on fertility either PGF induced estrus or Ovsynch protocol in dairy cows.

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Effects of treatment with a gonadotrophin-releasing hormone analogue on follicle development in dairy cows fed one of two different diets

BSAP Occasional Publication ◽

10.1017/s0263967x00034108 ◽

2001 ◽

Vol 26 (2) ◽

pp. 451-455

Author(s):

E.C.L. Bleach ◽

C.L. Moore ◽

H.J. Zeale ◽

P.G. Knight

Keyword(s):

Dairy Cows ◽

Luteal Phase ◽

Cycle Length ◽

Crude Protein ◽

Oestrous Cycle ◽

Follicle Development ◽

Releasing Hormone ◽

Ovulatory Follicle ◽

Metabolisable Energy ◽

Phase Length

AbstractFollicle development occurs in two or three waves during the bovine oestrous cycle. Artificially extending the duration of ovulatory follicle dominance influences pregnancy rates in cattle, as does the interval from emergence to oestrus in dairy cows undergoing spontaneous oestrous cycles. The objectives of the presented study were to determine whether the interval from ovulatory follicle emergence to oestrus might be altered by diet and/or gonadotropin-releasing hormone (GnRH) treatment. Lactating primiparous Holstein/Friesian cows (n=21) were randomly allocated to one of two diets at calving (Diet 1, n=ll, DM 480 g/kg, metabolisable energy 12.0 MJ/kg DM crude protein 178 g/kg DM, oil B 48 g/kg DM, neutral detergent fibre 318 g/kg DM and diet 2, n=10, DM 440 g/kg, metabolisable energy 12.1 MJ/kg DM, crude protein 172 g/kg DM, oil B 40 g/kg DM, neutral detergent fibre 300 g/kg DM). From 10 days after observed oestrus (oestrus 1), ovarian follicular and luteal development was monitored by daily transrectal ultrasonography until the subsequent oestrus and ovulation. A GnRH analogue was injected (i.m.; 10 μg) 12 days after oestrus 1 in 6 cows fed diet 1 and 5 cows fed diet 2. Oestrous cycle length was longer (p<0.05) in control cows fed diet 1 than those fed diet 2. Treatment with GnRH increased (p<0.005) cycle length in cows fed diet 2 but not those fed diet 1. Increases in cycle length observed were associated with longer luteal phase length. Follicular phase length was reduced (p<0.05) by GnRH treatment in cows fed diet 1. Ovulatory follicles emerged later (p<0.05) in control cows fed diet 1 than those fed diet 2. GnRH treatment delayed (p<0.01) the emergence of the ovulatory follicle in cows fed diet 2, this delay was associated with an increase (p<0.05) in the incidence of 3 follicle waves in oestrous cycles following GnRH treatment. The interval from emergence of the ovulatory follicle to the subsequent oestrus was similar among the treatment groups. We conclude that treatment with GnRH during the mid-luteal phase may delay the emergence of the ovulatory follicle. However, the response is dependent on diet fed. Where ovulatory follicle emergence is delayed, the interval from emergence to the subsequent oestrus was unaffected since oestrous cycle length is extended.

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Follicular dynamics, corpus luteum growth and regression in lactating dairy cattle

Canadian Journal of Animal Science ◽

10.4141/cjas91-007 ◽

1991 ◽

Vol 71 (1) ◽

pp. 61-68 ◽

Cited By ~ 35

Author(s):

C. Taylor ◽

R. Rajamahendran

Keyword(s):

Dairy Cows ◽

Corpus Luteum ◽

Estrous Cycle ◽

Follicular Growth ◽

Dominant Follicle ◽

Lactating Dairy Cows ◽

Ovulatory Follicle ◽

Second Wave ◽

Lactating Dairy Cattle ◽

Follicular Dynamics

Ultrasound imaging and progesterone (P4) profiles were used to characterize follicular and corpus luteum (CL) growth and regression in 10 cycling dairy cows. Thirteen of sixteen cycles were characterized by two waves of follicular growth, the second wave giving rise to the ovulatory follicle. The remaining three cycles had three waves. There was no difference between two- and three-wave cycles with regard to the day of emergence of the first or second dominant follicle (day 2.5 ± 0.9 vs. day 2.4 ± 1.2 and day 12.4 ± 1.6 vs. day 12.0 ± 2.0, respectively) or the onset of regression of the first dominant follicle (day 12.5 ± 1.5 vs. day 12.3 ± 1.5). In two wave cycles, estrous cycle length was shorter (20.8 ± 1.7 d vs. 29.7 ± 4.9 d), the first day of decline in P4 (day 16.2 ± 1.5 vs. day 23.7 ± 5.5) and the onset of CL regression (day 17.1 ± 1.3 vs. day 24.3 ± 5.5) was earlier. It is concluded that two waves of follicular growth in an estrous cycle is the norm in lactating dairy cows. The presence of an additional wave is due to a prolonged luteal phase. Key words: Follicle, corpus luteum, estrous cycle, dairy cow

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Effect of Progesterone Concentration During Follicle Development on Subsequent Ovulation, Fertilization, and Early Embryo Development in Lactating Dairy Cows.

Biology of Reproduction ◽

10.1093/biolreprod/85.s1.685 ◽

2011 ◽

Vol 85 (Suppl_1) ◽

pp. 685-685 ◽

Cited By ~ 6

Author(s):

Milo C. Wiltbank ◽

Paulo D. Carvalho ◽

Abdulkadir Kaskin ◽

Katherine Suzanne Hackbart ◽

Murillo A. Meschiatti ◽

...

Keyword(s):

Dairy Cows ◽

Embryo Development ◽

Early Embryo ◽

Follicle Development ◽

Progesterone Concentration ◽

Early Embryo Development ◽

Lactating Dairy Cows

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Impact of circulating concentrations of progesterone and antral age of the ovulatory follicle on fertility of high-producing lactating dairy cows

Reproduction Fertility and Development ◽

10.1071/rd11917 ◽

2012 ◽

Vol 24 (1) ◽

pp. 267 ◽

Cited By ~ 33

Author(s):

J. Richard Pursley ◽

Joäo Paulo N. Martins

Keyword(s):

Dairy Cows ◽

Dairy Cow ◽

Gonadotropin Releasing Hormone ◽

Oestrous Cycle ◽

Dairy Production ◽

Management Issue ◽

Lactating Dairy Cows ◽

Ovulatory Follicle ◽

The World ◽

Conception Rates

Dairy cow infertility negatively affects profit of dairy production enterprises around the world, and enhancing conception rates of dairy cows is a critical management issue to resolve. It appears that conception rates of dairy cows are attenuated due to reduced progesterone concentrations in circulation during growth of the ovulatory follicle. It is not clear how reduced progesterone influences fertility, but data presented in this brief review suggest that it can be somewhat reversed through increasing concentrations of progesterone during the growth of the ovulatory follicle before luteolysis. Ovsynch protocols may be utilised to enhance progesterone concentrations through the induction of an accessory corpus luteum (CL) following the initial gonadotropin-releasing hormone (GnRH) treatment. Cows at Day 13 of the oestrous cycle with a 7-day-old accessory CL had ~50% more progesterone at the time of prostaglandin injection of Ovsynch compared with cows with only a Day 13 CL. Ovsynch can consistently induce an accessory CL following the initial GnRH treatment if cows are on Days 6 or 7 of the oestrous cycle at the time of treatment. Pre-synchrony strategies are critical to enhance the probability that cows will be on Days 6 or 7 at first GnRH treatement of Ovsynch.

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The effect of ovulatory follicle size at the time of insemination onpregnancy rate in lactating dairy cows

TURKISH JOURNAL OF VETERINARY AND ANIMAL SCIENCES ◽

10.3906/vet-1506-59 ◽

2016 ◽

Vol 40 ◽

pp. 68-74 ◽

Cited By ~ 5

Author(s):

Abdulkadir KESKİN ◽

Gülnaz MECİTOĞLU ◽

Ebru BİLEN ◽

Barış GÜNER ◽

Abdulkadir ORMAN ◽

...

Keyword(s):

Dairy Cows ◽

Lactating Dairy Cows ◽

Ovulatory Follicle ◽

Follicle Size

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Some effects of post-oestrous hormonal therapies on conception rates and resubmission rates in lactating dairy cows

BSAP Occasional Publication ◽

10.1017/s0263967x00033681 ◽

2001 ◽

Vol 26 (1) ◽

pp. 195-208 ◽

Cited By ~ 2

Author(s):

K. L. Macmillan ◽

V.K. Taufa ◽

A.M. Day ◽

V.M. Eagles

Keyword(s):

Dairy Cows ◽

Ovarian Follicle ◽

Follicle Development ◽

Early Lactation ◽

Detection Rates ◽

Ovarian Follicle Development ◽

Lactating Dairy Cows ◽

Conception Rates ◽

Hormonal Therapies ◽

The Impact

AbstractA range of hormonal therapies has been evaluated to potentially improve the reproductive performance of lactating dairy cows. Early lactation treatments with gonadotrophin releasing hormone (GnRH) or prostaglandin F2∝(PGF) may reduce the interval to first insemination or increase the conception rate to first insemination, but mainly in cows which have had a difficult pueperium or which are in herds with low conception rates. These two hormones, as well as progesterone and oestradiol benzoate (ODB) are commonly used either singly, or in combination (GnRH + PGF; progesterone + ODB + PGF) to synchronise the oestrus preceding first inseminations. None of these synchrony treatments is associated with increased conception rates. Extensive series of trials have been completed to identify post-oestrous or post-insemination hormonal therapies which could increase conception rates to the preceding insemination. The wide variation in results has precluded any being commonly regarded as sufficiently reliable for routine use. Nonetheless, meta-analyses have shown that GnRH treatment at insemination or in late dioestrus (11 to 13 day post-first insemination) can significantly increase “the risk of pregnancy”. Insemination treatments have been most effective with repeat breeders (+22.5%), whereas late dioestrous treatments (10%) may be dose and analogue specific (10 μg buserelin). Although metoestrous supplementation with progesterone can stimulate early embryonic development, the associated reduction in oestrous cycle length also reduces conception rates in heifers. Late dioestrous use of GnRH can prevent both of these negative effects. Early dioestrous supplementation with progesterone may enhance production of interferon tau, but this potentially beneficial effect has not been able to be reliably translated into increased conception rates. Many of these hormonal therapies are associated with altered patterns of ovarian follicle development which are similar to those in some synchrony treatments preceding first insemination. Recent studies have indicated that OBD and progesterone can be used to synchronise returns to service and increase the submission rate for second inseminations made about 3 weeks after first inseminations. This can make the non-return rate a more accurate measure of the response to a hormonal treatment and potentially overcome confusing impressions created when oestrous detection rates may be around 50%. Even if effective hormonal therapies are successfully developed, the results may be compromised by environmental factors such as heat stress, energy balance or energy partitioning for lactation. These factors may reduce oocyte quality, fertilization rates or normal uterine secretion patterns. Reduced conception rates associated with high daily milk yields in early lactation may not be able to be remedied simply with hormonal supplementation or by altering patterns of ovarian follicle development. Under these circumstances, controlling the inter-service interval could reduce the impact of the lowered conception rates.

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Diameter of the ovulatory follicle at timed artificial insemination as a predictor of pregnancy status in lactating dairy cows subjected to GnRH-based protocols

Theriogenology ◽

10.1016/j.theriogenology.2015.03.034 ◽

2015 ◽

Vol 84 (3) ◽

pp. 377-383 ◽

Cited By ~ 13

Author(s):

M.G. Colazo ◽

A. Behrouzi ◽

D.J. Ambrose ◽

R.J. Mapletoft

Keyword(s):

Dairy Cows ◽

Artificial Insemination ◽

Lactating Dairy Cows ◽

Ovulatory Follicle ◽

Pregnancy Status ◽

Timed Artificial Insemination

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Association between ovarian follicle development and pregnancy rates in dairy cows undergoing spontaneous oestrous cycles

Reproduction ◽

10.1530/rep.1.00190 ◽

2004 ◽

Vol 127 (5) ◽

pp. 621-629 ◽

Cited By ~ 73

Author(s):

Emma C L Bleach ◽

Richard G Glencross ◽

Philip G Knight

Keyword(s):

Dairy Cows ◽

Pregnancy Rate ◽

Ovarian Follicle ◽

Pregnancy Rates ◽

Developmental Competence ◽

Follicle Development ◽

Ovarian Follicle Development ◽

Ovulatory Follicle ◽

Ovulatory Follicles ◽

First Time

Ovarian follicle development continues in a wave-like manner during the bovine oestrous cycle giving rise to variation in the duration of ovulatory follicle development. The objectives of the present study were to determine whether a relationship exists between the duration of ovulatory follicle development and pregnancy rates following artificial insemination (AI) in dairy cows undergoing spontaneous oestrous cycles, and to identify factors influencing follicle turnover and pregnancy rate and the relationship between these two variables. Follicle development was monitored by daily transrectal ultrasonography from 10 days after oestrus until the subsequent oestrus in 158 lactating dairy cows. The cows were artificially inseminated following the second observed oestrus and pregnancy was diagnosed 35 days later. The predominant pattern of follicle development was two follicle waves (74.7%) with three follicle waves in 22.1% of oestrous cycles and four or more follicle waves in 3.2% of oestrous cycles. The interval from ovulatory follicle emergence to oestrus (EOI) was 3 days longer (P < 0.0001) in cows with two follicle waves than in those with three waves. Ovulatory follicles from two-wave oestrous cycles grew more slowly but were approximately 2 mm larger (P < 0.0001) on the day of oestrus. Twin ovulations were observed in 14.2% of oestrous cycles and occurred more frequently (P < 0.001) in three-wave oestrous cycles; consequently EOI was shorter in cows with twin ovulations. Overall, 57.0% of the cows were diagnosed pregnant 35 days after AI. Linear logistic regression analysis revealed an inverse relationship between EOI and the proportion of cows diagnosed pregnant, among all cows (n = 158; P < 0.01) and amongst those with single ovulations (n = 145; P < 0.05). Mean EOI was approximately 1 day shorter (P < 0.01) in cows that became pregnant than in non-pregnant cows; however, pregnancy rates did not differ significantly among cows with different patterns of follicle development. These findings confirm and extend previous observations in pharmacologically manipulated cattle and show, for the first time, that in dairy cows undergoing spontaneous oestrous cycles, natural variation in the duration of post-emergence ovulatory follicle development has a significant effect on pregnancy rate, presumably reflecting variation in oocyte developmental competence.

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