scholarly journals Effect of dietary-induced changes in plasma insulin concentrations during the early post partum period on pregnancy rate in dairy cows

Reproduction ◽  
2009 ◽  
Vol 137 (4) ◽  
pp. 759-768 ◽  
Author(s):  
P C Garnsworthy ◽  
A A Fouladi-Nashta ◽  
G E Mann ◽  
K D Sinclair ◽  
R Webb
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Plasma Insulin ◽  
Post Partum ◽  
Ovarian Follicle ◽  
Developmental Competence ◽  
Cyclic Activity ◽  
Plasma Insulin Concentration ◽  
Mating Period ◽  
Ovarian Follicle Development

Dietary stimulation of insulin in post partum dairy cows has been found to enhance ovarian follicle development but to impair oocyte developmental competence. The objective of this study was to test the hypothesis that pregnancy rate would be improved by feeding a diet to stimulate higher insulin (H) until cows resumed ovarian cyclic activity after parturition, and then feeding a diet to lower insulin (L) during the mating period. Each diet was fed to 30 post partum dairy cows until their first rise in milk progesterone, when 15 cows in each group were transferred to the other diet (treatments HL and LH) and 15 cows in each group remained on their original diet (treatments HH and LL) until 120 days post partum. Treatments did not affect dry matter intake, milk yield and metabolisable energy balance. Plasma insulin concentration was elevated in cows fed on H compared with cows fed on L. Treatment did not affect days to first progesterone rise, first oestrus or first insemination. At 120 days post partum, 27% of cows on each of treatments HH, LL and LH were pregnant, but 60% of cows on treatment HL were pregnant (P=0.021). These findings support the concept that physiological relationships between insulin and the reproductive system vary according to stage of the reproductive cycle, and suggest that pregnancy rate can be enhanced by a two-diet strategy tailored to optimise responses before and after the first post partum ovulation.

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

Reproduction ◽  
2004 ◽  
Vol 127 (5) ◽  
pp. 621-629 ◽  
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.

scholarly journals Effects of bovine somatotrophin (bST) on ovarian function in post-partum beef cows

1996 ◽  
Vol 8 (6) ◽  
pp. 951 ◽  
Author(s):  
LP Andrade ◽  
SM Rhind ◽  
IA Wright ◽  
SR McMillen ◽  
PJ Goddard ◽  
...  
Keyword(s):  
Ovarian Function ◽  
Post Partum ◽  
Ovarian Follicle ◽  
Beef Cows ◽  
Ovarian Follicle Development ◽  
Factor I ◽  
Glucose Injection ◽  
Igf I ◽  
And Function ◽  
Bovine Somatotrophin

The effects of bovine somatotrophin (bST) on ovarian follicle development and function and associated gonadotrophin profiles during the first nine weeks post partum were investigated in beef cows. Thirty-two cows (Shorthorn x Galloway) in moderately low body condition (BC) at calving were fed to maintain BC thereafter. At Weeks 2, 4, 6 and 8 post partum, animals were injected with 320 mg bovine somatotrophin (bST) (T, treated; n = 17) or with the carrier oil only (C, control; n = 15). Ovulation occurred in 4 of 17 T cows and 0 of 15 C cows (P = 0.10) by nine week post partum. Treatment with bST did not affect the numbers of small (3-8 mm in diameter) or large (> 8 mm in diameter) follicles or the granulosa cell populations but enhanced the oestradiol (P < 0.05) and insulin-like growth factor-I (IGF-I) content (P < 0.01) of large follicles by nine weeks post partum. It did not significantly affect the testosterone concentrations of large follicles. Circulating concentrations of growth hormone (GH) and IGF-I were higher in T cows than in C cows (P < 0.001) but were unrelated to gonadotrophin profiles or gonadotrophin receptor concentrations in the follicles. At Week 8, plasma insulin concentrations were higher in T cows than in C cows both before (P < 0.05) and after (P < 0.05) glucose injection. It is concluded that GH may play an important role in mediating the effects of nutritional state on ovarian function during the post-partum period, possibly through alteration of intrafollicular IGF-I concentrations.

scholarly journals REDUCTION OF THE VOLUNTARY WAITING PERIOD BY USE OF HORMONAL PROTOCOLS AND FIXED-TIME ARTIFICIAL INSEMINATION (FTAI) IN DAIRY COWS

2012 ◽  
Vol 17 (3) ◽  
Author(s):  
Miriane Suplicy ◽  
Haroldo Suplicy Filho ◽  
Luiz Ernandes Kozicki ◽  
José Carlos dos Santos Breda ◽  
Romildo Romualdo Weiss ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Pregnancy Rate ◽  
Artificial Insemination ◽  
Post Partum ◽  
Fixed Time ◽  
Estradiol Benzoate ◽  
Control Group ◽  
Waiting Period ◽  
Equine Chorionic Gonadotropin ◽  
Voluntary Waiting Period

ABSTRACT: The aim of this study was to reduce the waiting voluntary period in dairy cows by administration of two different hormonal protocols for estrus synchronization and fixed-time artificial insemination (FTAI). One hundred twenty-eight Holstein dairy cows were studied. Three groups (G) were carried out: G1 (44 treated), G2 (34 treated) and G3 (50 as control). In the treated cows the following hormonal protocols was applied between 40 and 45 days post partum: G1- Day 0 (D0) - bovine intravaginal device containing progesterone (P4) plus 1.0 mg of estradiol benzoate (EB), D8 - removal of the P4, plus 0.5 mg of cloprostenol plus 400 IU of equine chorionic gonadotropin (eCG), D9 - 1.0 mg of EB and FTAI after 36 hours. G2 - D0 - P4 intravaginal plus 50 mcg of gonadotropin-releasing hormone (GnRH), D7 - removal of the P4 plus cloprostenol plus 400 IU eCG; D9 - 50 mcg of GnRH and FTAI 16 hours after. G3 – Control group inseminated 12 hours after the visual estrus. Results: G1 and G2 were inseminated (FTAI) respectively in the D55.5 and D56.8 after calving, while the G3 in the D84.5 (p<0.01).  The pregnancy rate in the G1, G2 and G3 was respectively 47.0, 46.1 and 35.8% (p>0.05).  In Conclusion: there was significant reduction in the voluntary waiting period in treated cows and higher pregnancy rate although not significant.

scholarly journals Effect of bovine somatotropin (growth hormone) treatment on gonadotropin profiles and ovarian follicle populations during the postpartum period in beef cows in low body condition

1993 ◽  
Vol 1993 ◽  
pp. 89-89
Author(s):  
L.P. Andrade ◽  
S.M. Rhind ◽  
I.A. Wright ◽  
S.R. McMillen ◽  
T.K. Whyte
Keyword(s):  
Growth Hormone ◽  
Body Condition ◽  
Growth Hormone Treatment ◽  
Ovarian Function ◽  
Post Partum ◽  
Ovarian Follicle ◽  
Hormone Treatment ◽  
Beef Cows ◽  
Follicle Development ◽  
Ovarian Follicle Development

Cows in low body condition exhibit a prolonged postpartum anoestrous period and a delayed return to normal follicular function (Prado et al 1990). Previous studies have shown that the effects of body condition on gonadotrophin profiles are inconsistent (Wright et al 1990; Rhind et al 1992) indicating that the effects of body condition on ovarian function cannot be explained by changes in gonadotrophin profiles alone. Since nutritional state influences growth hormone profiles which in turn can affect ovarian function (Gong et al 1991), it was postulated that the effects of body condition on the duration of postpartum anoestrus could be mediated through changes in profiles of this hormone.The aim of the present study was to determine the effect of growth hormone on ovarian follicle development and associated gonadotrophin profiles in post-partum beef cows.

scholarly journals Effect of Utilization of Single or Double Prostaglandin Administration Within an Ovsynch Fixed-Time Artificial Insemination Protocol During Summer Season in Dairy Cows

2019 ◽  
Vol 19 (3) ◽  
pp. 725-731
Author(s):  
Giorgio Morini ◽  
Fernando López-Gatius ◽  
Irina Garcia-Ispierto ◽  
Fabio De Rensis
Keyword(s):  
Single Dose ◽  
Dairy Cows ◽  
Pregnancy Rate ◽  
Artificial Insemination ◽  
Post Partum ◽  
Winter Season ◽  
Fixed Time ◽  
Summer Season ◽  
Cumulative Pregnancy Rate ◽  
June July

AbstractThis study investigated the fertility of dairy cows during summer season after treatment with a single or double PGF2α in a progesterone (P4)-based Ovsynch protocol for fixed-time artificial insemination (FTAI). The data were compared to a treatment effectuated during winter season. Two groups of 60 dairy cows each were randomly assigned on day 60 post-partum to single PGF2α or double PGF2α group. At removal of the P4 treatment the single PGF2α group received a single dose and the double PGF2α group received two doses of PGF2α at 24 hours apart. In each group, 30 cows were treated during the summer (June, July and August) and 30 cows during the winter (December, January and February) season. During summer season a double PGF2α dose did not influence pregnancy rate at FTAI but improved cumulative pregnancy rate 60 days after FTAI (43% vs 69% for single PGF2α and double PGF2α administration, respectively; P<0.05). During winter season the single or double PGF2α administration did not modify PR or cumulative PR. In conclusion, during summer the utilization of a double instead of single PGF2α treatment into a P4-based Ovsynch-FTAI protocol did not increase pregnancy rate at FTAI but improved cumulative pregnancy rate.

RELATIONSHIP BETWEEN INSULIN CONCENTRATIONS IN PLASMA AND PANCREAS OF FOETAL AND WEANLING RATS

1970 ◽  
Vol 48 (4) ◽  
pp. 553-561 ◽  
Author(s):  
E. BLÁZQUEZ ◽  
E. MONTOYA ◽  
CLEMENTE LÓPEZ QUIJADA
Keyword(s):  
Plasma Insulin ◽  
Striated Muscle ◽  
Slow Growth ◽  
Post Partum ◽  
Newborn Rat ◽  
Plasma Insulin Concentration ◽  
Pregnant Rats ◽  
Weanling Rats

SUMMARY During the third part of pregnancy in the rat the concentrations of plasma insulin and tissue glycogen in the foetus increase progressively. These levels and the release of insulin by pancreas incubated in vitro were significantly higher than the values found in adult non-pregnant rats. After birth the correlation between plasma insulin concentration and the stores of glycogen was also evident. In the first day of life, the concentrations of plasma insulin, glycogen in liver, striated muscle and kidney decreased significantly; these values decrease even more during the first 15 days of lactation. After weaning started (20 days post partum), rapid increases of insulin and glycogen were observed, parallel to the slow growth of the newborn rat during the first 15 days of life and the more rapid rate of growth after 20 days. Similarly, the insulin content of the pancreas increased more significantly during the period in which pancreatic weight and plasma insulin concentrations increased more slowly. These results show that when plasma insulin concentrations increase, body growth and stores of glycogen are higher, suggesting an anabolic role of insulin in the foetal and newborn rat.

Effect of propylene glycol on fertility of postpartum dairy cows experiencing seasonal heat stress

2016 ◽  
Vol 50 (1) ◽  
Author(s):  
Atilla Yildiz ◽  
Zeki Erisir
Keyword(s):  
Heat Stress ◽  
Treatment Group ◽  
Energy Balance ◽  
Dairy Cows ◽  
Pregnancy Rate ◽  
Propylene Glycol ◽  
Post Partum ◽  
Control Group ◽  
Energy Status ◽  
Seasonal Heat

The objective of this study was to evaluate effects of a daily oral drench of Propylene Glycol (PG) on fertility in dairy cows experiencing seasonal heat stress. In treatment group, cows (n=9) were treated with drenching 250 ml propylene glycol once daily from 3 to 15 days post-partum following the morning milking. Another group of cows (n=9) was selected as untreated control. The serum beta-hydroxybutyrate (BHBA) concentrations were used as indicators of energy status of the cows. Days to onset of luteal activity, calving to first service interval and pregnancy rate to first service were used to evaluate the reproductive performance. There was no difference in onset of luteal activity postpartum between the treatment and control groups. But the cows in the treatment group tended to have shorter intervals from calving to first insemination compared with cows in control group. The pregnancy rate to first service for cows treated with PG was 2.50 times greater compared with cows in control group. The energy balance was less negative for treatment group compared with control cows. In conclusion, although, drenching with 250 mL of PG per day from 3 to 15 days after calving did not improve the onset of luteal activity postpartum, treated cows tended to have shorter intervals from calving until first service. Propylene glycol administration would improve the negative energy balance status as observed by serum BHBA concentration, which might be an advantage to increase pregnancy rate at first AI in dairy cows experiencing seasonal heat stress.

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

2001 ◽  
Vol 26 (1) ◽  
pp. 195-208 ◽  
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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