Prostaglandin treatment and subsequent cystic ovarian disease in Holstein cows

Using computerized herd health data, a prospective cohort study was devised to determine whether cows treated with prostaglandins had a higher incidence of cystic ovarian disease than comparable cows not treated. Of 744 cows selected as having diseases for which prostaglandin administration may be indicated, 240 received prostaglandin. Sixteen cows had cystic ovarian disease following prostaglandin administration. Chi-square analysis showed no association (P greater than 0.10) between cystic ovarian disease and the use of prostaglandin. Incidence of cystic ovarian disease within 150 days of calving in clinically normal cows was compared with that of cows with reproductive disorders. Cows with reproductive disorders had a significantly (P less than 0.01) higher incidence of cystic ovarian disease.     

Lack of LH response to exogenous estradiol in heifers with ACTH-induced ovarian follicular cysts.

The aim of the present study was to examine the LH response to exogenous estradiol in 4 heifers with ACTH-induced ovarian follicular cysts. During the control experiment, administration of estradiol 24 hr after PGF2alpha in luteal phase heifers resulted in a LH response in all 4 heifers. The LH response was obtained between 16-20 hr after estradiol administration. The peak LH concentration (Mean +/- SEM; 5.1 +/- 0.8 ng/ml) during the control study was significantly different (P<0.05) from the concentration after cyst formation. None of the 4 heifers responded to estradiol after ovarian cyst formation. This result suggests that heifers with ACTH-induced ovarian follicular cysts may have a defective hypothalamio-pituitary response to exogenous estradiol similar to cows with spontaneous ovarian cysts.     

Thirteen-weeks subcutaneous treatment with oestradiol or an oestradiol/progesterone combination in beagle bitches

High doses of oestradiol (150 micrograms/kg) or an oestradiol/progesterone combination (150 micrograms/kg oestradiol plus 6.25 mg/kg progesterone) were administered subcutaneously on alternate days to immature ovariectomised and mature intact female Beagle dogs for 13 weeks. The effects of hormonal treatment on different parameters were studied. The results revealed severe anaemia (mainly at week 3) and the blood films showed morphological indication of blood loss and abnormal erythrogenesis. Neutrophil leucocytosis and non-progressive thrombocytopenia were also observed. Treatment with oestradiol alone induced changes in the endometrial stroma and myometrium, whereas treatment with the oestradiol/progesterone combination induced cystic endometrial hyperplasia. The pituitary glands of the dogs treated with oestradiol alone had a slight increase in the number of ACTH cells. These cells and STH cells showed cytological changes indicative of accelerated secretory activity; the PRL and gonadotropin-producing cells were not affected significantly. The oestradiol/progesterone combination increased the number of ACTH and PRL cells. These cells as well as STH cells exhibited several cytological criteria typical of a pituitary cell with accelerated activity; the gondadotropin-producing cells showed involutionary changes. The mammary glands of oestradiol-treated dogs showed stromal and ductal cell proliferation; whereas the oestradiol/progesterone combination induced secretory epithelial cell proliferation in addition to stromal and ductal cell proliferation.     

Fertility parameters of dairy cows with cystic ovarian disease after treatment with gonadotrophin-releasing hormone

Fertility data were collected every four weeks for 10 years from 40 herds of Holstein-Friesian dairy cattle. The data collected during 925 lactations from cows with cystic ovarian disease which were treated with 500 microg gonadorelin were compared with data from a control group of 13,869 normal lactations. The intervals between parturition and first insemination and between parturition and conception were significantly shorter (P<0.001) in the normal cows, but the interval between first insemination and conception was not. The overall conception rate tended to be higher (P<0.10) in the normal cows, but the conception rate after the first insemination was significantly higher (P<0.001) and the number of services per conception was significantly lower (P=0.008) in the normal cows.     

Administration of progesterone to cows with ovarian follicular cysts results in a reduction in mean LH and LH pulse frequency and initiates ovulatory follicular growth

Cows with ovarian follicular cysts were treated with progesterone to determine whether a reduction in LH concentrations and initiation of ovulatory follicular waves would occur. Cysts were diagnosed using transrectal ultrasonography when single follicular structures > 20 mm or multiple structures > 15 mm in diameter were present for 7 d in the presence of low progesterone concentrations. Three groups were studied: 1) cows with normal estrous cycles (CYC, n = 8); 2) cows with untreated cysts (CYST, n = 7); and 3) cows with cysts treated with two progesterone-releasing intravaginal devices (PRID, n = 8) for 9 d. Ovaries were examined with transrectal ultrasonography, and blood samples were collected daily for analysis of progesterone and FSH. Serial blood samples for determination of mean LH and LH pulse frequency were collected on d 0 (CYST and PRID cows only), 1, 5, 9, and 10. Progesterone concentrations were higher in PRID cows than in CYST cows throughout the PRID treatment period (P < .002). On d 0, LH pulse frequency was similar (P = .10) in PRID (6.6+/-.6 pulses/8 h) and CYST cows (5.1+/-.6 pulses/8 h), but mean LH tended to be higher (P = .054) on d 0 in PRID cows (2.5+/-.2 ng/mL) than in CYST cows (1.9+/-.2 ng/mL). Mean LH and LH pulse frequency decreased (P < .002) by d 1 in PRID cows (1.1+/-.2 ng/mL, 1.8+/-.6 pulses/8 h) compared with CYST cows (2.1+/-.2 ng/mL, 5.6+/-.6 pulses/8 h) and remained lower throughout most of the experimental period. The FSH concentrations were higher (P < .01) in PRID cows than in CYC and CYST cows on d 3 and 4. The increase in FSH concentrations preceded emergence of the PRID-induced follicular wave. All PRID cows and four of seven CYST cows initiated new follicular waves during the period of PRID treatment. Follicular waves were initiated later (P < .05) in CYST cows (d 5.2+/-1.7) and PRID cows (d 5.5+/-.6) than in CYC cows (d 1.8+/-.3). Cysts were smaller (P < .01) at the end of the treatment period in PRID cows compared with CYST cows. No CYST cows ovulated, but all PRID cows ovulated newly developed follicles 3 or 4 d after PRID removal. Treatment with exogenous progesterone reduced LH in cows with cysts, and this was followed by development of normal ovulatory follicles.     

Insulin-like growth factor I in sera, ovarian follicles and follicular fluid of cows with spontaneous or induced cystic ovarian disease

The objective of this research was to determine changes in IGF-I levels in serum and follicular fluid, and immunoreactivity of the follicle wall of cows with spontaneous (slaughter specimens) or ACTH-induced follicular cysts, and to compare results to normal cycling (control) cows after selection of the ovulatory follicle. Concentrations of IGF-I in serum did not differ between control and cystic animals (p=0.76). Fluid from the ovulatory follicle in control cows had 41% higher concentrations of IGF-I than that from cystic follicles collected at slaughter (spontaneous cysts; p<0.05) and 70% higher than that in induced follicular cysts (p<0.05). An intense positive immunostaining with anti-IGF-I was observed in granulosa cells (p<0.05) and in the theca interna (p<0.05) of secondary and tertiary follicles in all three groups of animals, but staining was less intense in cystic (p<0.05) and atretic follicles (p<0.05). This study provides evidence to suggest that cystic ovarian disease in cattle is associated with decreased concentrations of IGF-I in follicular fluid, but not in serum, and decreased production of IGF-I in the follicular wall. These data support the notion that IGF-I plays a role in the regulation of folliculogenesis, and may participate in the pathogenesis of cystic ovarian disease in cattle.     

Reproductive performance of anovulatory anoestrous postpartum dairy cows following treatment with two progesterone and oestradiol benzoate-based protocols, with or without resynchrony

AIMS: (a) To compare the reproductive performance of anovulatory anoestrous (AA) postpartum dairy cows following treatment with 1 of 2 progesterone (P4) and oestradiol benzoate (ODB)-based treatment regimens; (b) To determine whether resynchronisation of cows initially treated for AA would improve reproductive performance and; (c) to determine whether cows not detected in oestrus but with a corpus luteum (CL) present (NDO/CL+), treated with P4 and ODB, would conceive earlier than untreated controls. METHODS: Cows (n=1386) from 11 herds, that had not been detected in oestrus before the start of the seasonal mating period (PSM) and in which a CL was not detected were diagnosed AA, blocked by age (2 or >2 years old), then randomly assigned to be treated with an intravaginal P4-releasing device for either 6 (6-Day group) or 8 days (8-Day group). Cows in the 8-Day group were injected intramuscularly (IM) with 2 mg ODB at device insertion and all cows were injected with 1 mg ODB 24 h after device removal (Day 0). Cows detected in oestrus from Days 0-3 were subsequently assigned to be either resynchronised or left as untreated controls. Resynchronised cows had a used P4-releasing device reinserted on Day 14 for 8 days and were injected with 1 mg ODB at device reinsertion and again 24 h after device removal. NDO/CL+ cows were assigned to be either treated the same as the 8-Day group or left as untreated controls. All cows were inseminated on detection of oestrus and pregnancy tested approximately 10 weeks after the PSM and again 6-8 weeks after the end of the mating period. RESULTS: For AA cows, the 14-day submission rate was similar between 6-Day and 8-Day groups (p0.1). However, the pregnancy rate by Day 14 was higher for the 8-Day than the 6Day group (43.0% vs 35.2%; p=0.006). Resynchrony treatment decreased the 14-day pregnancy rate compared with untreated controls (35.2% vs 42.5%; p=0.026). The resynchrony treatment increased the submission rate between Days 14-28 for non-pregnant cows compared with untreated controls (80.6% vs 57.4%; p=0.049). However, conception rate to resynchronised heats was lower than for cows that returned to oestrus naturally (56.6% vs 67.9%; p=0.025). Neither initial treatment type nor resynchrony treatment increased the 28-day pregnancy rate (p>0.1). There were no differences between treatment groups in the final non-pregnant rate (4.5% vs 4.6%; p>0.1). Treated NDO/CL+ cows had a higher 14-day submission rate (88.1% vs 49.4%; p>0.001), higher 14-day and 28-day pregnancy rates (42.9% vs 20.7%, p>0.001 and; 56.0% vs 42.5%, p=0.094, respectively) and conceived earlier (21 vs 36 days from PSM to median day of conception; p>0.05), than untreated NDO/CL+ cows. CONCLUSIONS: The 8-Day, ODB-P4-ODB treatment regimen resulted in a higher pregnancy rate by 14 days but not 28 days than the 6-Day, P4-ODB treatment. The resynchrony treatment increased the proportion of non-pregnant cows inseminated on days 14-28, but did not increase the 28-day pregnancy rate or final pregnancy rate. Treatment of NDO/CL+ cows with the 8-Day, ODB-P4-ODB treatment improved reproductive performance compared with no treatment.     

The reproductive performance of anoestrous dairy cows following treatment with progesterone and oestradiol prior to the start of mating

AIMS: To determine the reproductive performance of cows diagnosed as anoestrus prior to the planned start of mating (PSM) when they were either treated when first diagnosed, or left untreated until 16 days after the PSM. METHODS: A clinical trial was conducted during the 1996/97 and 1997/98 breeding seasons involving 823 anoestrous dairy cows in 14 herds. On Day -8 (PSM = Day 0), cows in one group (Treated) were each treated with an intravaginal device containing 1.9 g of progesterone (CIDR). The CIDR device was removed on Day -2, and on Day -1 each cow was injected intramuscularly with 1 mg oestradiol benzoate. Cows in the second group (Control) remained untreated at the time of first examination. All cows detected in oestrus after the PSM were mated by artificial insemination (AI) or a bull. Sixteen days after the PSM, all cows that had not been mated were presented for veterinary examination, and those which were still classified as anoestrus were treated with the previously described CIDR regimen. Pregnancy status and approximate date of conception were determined by palpation per rectum 10 -13 weeks after the PSM or 6 weeks after the end of the mating period. RESULTS: Treatment of anoestrous cows 8 days before the PSM significantly increased the number of cows detected in oestrus (95.0% vs 63.1%; p<0.001) and conceiving (59.5% vs 38.8%; p<0.001) during the first 21 days of mating, and reduced the interval from PSM to conception by 7.5 days (p<0.001). There was no significant difference between the conception rate of cows mated following the CIDR treatment regimen compared to cows mated at their first spontaneous oestrus after calving (52.4% vs 58.3%; p = 0.143). CONCLUSION: Diagnosis and treatment of anoestrous dairy cows prior to the start of mating significantly improves their reproductive performance under the seasonal mating conditions typical of spring-calving New Zealand dairy herds.     

The reproductive performance of anoestrous dairy cows following treatment with progesterone and oestradiol prior to the start of mating

Aims: To determine the reproductive performance of cows diagnosed as anoestrus prior to the planned start of mating (PSM) when they were either treated when first diagnosed, or left untreated until 16 days after the PSM.

Methods: A clinical trial was conducted during the 1996/97 and 1997/98 breeding seasons involving 823 anoestrous dairy cows in 14 herds. On Day-8 (PSM = Day 0), cows in one group (Treated) were each treated with an intravaginal device containing 1.9 g of progesterone (CIDR).The CIDR device was removed on Day-2, and on Day-1 each cow was injected intramuscularly with 1 mg oestradiol benzoate. Cows in the second group (Control) remained untreated at the time of first examination. All cows detected in oestrus after the PSM were mated by artificial insemination (AI) or a bull. Sixteen days after the PSM, all cows that had not been mated were presented for veterinary examination, and those which were still classified as anoestrus were treated with the previously described CIDR regimen. Pregnancy status and approximate date of conception were determined by palpation per rectum 10-13 weeks after the PSM or 6 weeks after the end of the mating period.

Results: Treatment of anoestrous cows 8 days before the PSM significantly increased the number of cows detected in oestrus (95.0% vs 63.1%;p < 0.001) and conceiving (59.5% vs 38.8%;p < 0.001) during the first 21 days of mating, and reduced the interval from PSM to conception by 7.5 days (p < 0.001). There was no significant difference between the conception rate of cows mated following the CIDR treatment regimen compared to cows mated at their first spontaneous oestrus after calving (52.4% vs 58.3%; p = 0.143).

Conclusion: Diagnosis and treatment of anoestrous dairy cows prior to the start of mating significantly improves their reproductive performance under the seasonal mating conditions typical of spring-calving New Zealand dairy herds.     

Efficacy of intravaginal progesterone administration combined with prostaglandin f(2alpha) for cystic ovarian disease in Japanese Black cows

The objective of this study was to investigate cystic ovarian disease (COD) in commercial Japanese Black cows and to evaluate the efficacy of 7-day insertion of an intravaginal progesterone insert (CIDR) combined with prostaglandin F(2alpha) (PGF(2alpha)) at CIDR removal. Experiment 1 was conducted to group cysts into 4 patterns based on alteration of plasma progesterone (P(4)) concentrations on d -7 and d 0 (=CIDR insertion) with 1.0 ng/ml as the cut-off level by ultrasonographic examination of 28 cows with COD that were >or=40 days postpartum and anoestrous after calving. In Experiment 2, a total of 55 cows under the same conditions as in Experiment 1 were utilized, and the same regimen as in Experiment 1 was performed without 7 days of pre-observation before treatment. As a result, 92.9% of CLs on d 21 were highly formed in Experiment 1 and 83.6% were highly formed in Experiment 2. The conception rates within 60 days after CIDR removal were also satisfactory high and were 71.4% and 54.5%, respectively. There were no differences in any overall reproductive parameters between Experiments 1 and 2 (P>0.05). The average days between CIDR removal and conception were 24.4 +/- 5.3 and 24.0 +/- 6.5 days, respectively (P>0.05); therefore, the conception dates of the cows in Experiment 2 were at least 7 days earlier compared with Experiment 1. In conclusion, treatment with a CIDR and PGF(2alpha) against COD could minimize the risk of incorrect treatment and provide sufficient reproductive performance in Japanese Black cows.     

Plasma progesterone levels in sows with induced cystic ovarian follicles.

Large multiple cystic ovarian follicles were induced in three sows and small multiple cystic ovarian follicles were induced in three other sows by injections of adrenocorticotrophic hormone (ACTH) during the follicular phase of the oestrous cycle. Plasma progesterone levels in sows with large cysts were relatively high, while those of sows with small cystic follicles were low. Removal of the ovaries with large cysts from one sow resulted in a precipitous drop in progesterone levels indicating that the large cysts were primarily the source of progesterone. The method by which ACTH may induced cystic ovaries was also investigated. Plasma progesterone levels in two ovariectomised sows during ACTH treatment fluctuated markedly during a 24 h period achieving peak values of 4 or 5 ng/ml. The results suggest that progesterone of adrenal cortical origin may be a factor in the development of the cystic ovarian condition.     

Ovarian and endocrine responses associated with the treatment of cystic ovarian follicles in dairy cows with gonadotropin releasing hormone and prostaglandin F2alpha, with or without exogenous progesterone

The objectives of this observational study were to document ovarian and endocrine responses associated with the treatment of cystic ovarian follicles (COFs) in dairy cows, using gonadotropin releasing hormone (GnRH) and prostaglandin F2alpha (PGF) with or without exogenous progesterone. A secondary objective was to determine pregnancy establishment following synchronization of ovulation and timed insemination in cows diagnosed with COFs. In trial I, 18 Holstein cows diagnosed with COFs received 2 injections of 100 microg GnRH, 9 d apart, with 25 mg PGF given 7 d after the 1st GnRH. A new follicle developed in all 18 cows after the 1st GnRH, and 83% of cows ovulated following the 2nd GnRH. Cows were inseminated 16 h after the 2nd GnRH. Of the 17 cows available for pregnancy diagnosis, 7 were confirmed pregnant. In trial II, 8 cows with COFs received GnRH and an intravaginal progesterone device (CIDR) concurrently, then PGF 7 d later. The CIDR was removed 2 d after PGF administration. Plasma estradiol concentrations declined following CIDR insertion. In all cows, a new follicle developed following GnRH treatment; estradiol-surge and estrus occurred spontaneously after CIDR-removal. Seven of 8 cows ovulated the new follicle. In dairy cows diagnosed with COFs, treatment with GnRH followed by PGF 7 d later, with or without exogenous progesterone, resulted in the recruitment of a healthy new follicle; synchronization of ovulation and timed insemination resulted in a 41% pregnancy rate.     

Reproductive performance of post-partum anoestrous dairy cows treated with progesterone and oestradiol benzoate

Abstract

Extract

Recent studies have shown that the anoestrous condition of post-partum dairy cows can be treated with a combination of progesterone (for 5–7 days) and oestradiol benzoate (ODB, 1 mg injected at 24 or 48 h after termination of the progesterone treatment)(1) McDougall, S, and Macmillan, KL. 1993. Follicle waves, ovulation and oestrus in the postpartum cow. Proceedings of the 13th Seminar for the Society of Dairy Cattle Veterinarians of the New Zealand Veterinary Association, : 33–47.  [Google Scholar]. However, published data on the performance of this anoestrus treatment programme in commercial dairy herds is limited(2) Macmillan, KL,, Taufa, VK,, Day, AM, and McDougall, S. 1995. Some effects of using progesterone and oestradiol benzoate to stimulate oestrus and ovulation m dairy cows with anovulatory anoestrus. Proceedings of the New Zealand Society of Animal Production, 55: 239–241.  [Google Scholar]. During the 1994–95 and 1995–96 breeding seasons, performance of this anoestrus treatment programme was determined in nine and six spring-calving herds, respectively. In each herd, cows that had not been detected in oestrus using the tailpainting technique by Day -7 (Day 0 = start of the breeding season) were examined per rectum by each herd owner's attending veterinarian for the presence of a palpable corpus luteum (CL) on the ovary. Cows with a palpable CL or with an enlarged or infected uterus were excluded. Throughout the trial period, anoestrous cows were managed together with the cycling cows.     

Plasma progesterone concentrations in dairy cows with cystic ovaries and clinical responses following treatment with fenprostalene

Sixty-two dairy cows diagnosed as having cystic ovarian degeneration were used to study the correlation between rectal palpation findings and plasma progesterone concentrations and the response of cysts to treatment using fenprostalene, a luteolytic agent. Rectal palpation accurately determined the presence of luteal cysts as confirmed by plasma progesterone concentrations of 3 ng/mL or more. Treatment with fenprostalene was very effective for luteal cysts: a high percentage of treated cows exhibited estrus within seven days after treatment. The conception rate following artifical insemination during the induced estrus was 87.5% (21/24). Rectal palpation was much less accurate for the diagnosis of follicular cysts. Cows diagnosed as having follicular cysts had wide variations in plasma progesterone concentrations. Response to fenprostalene treatment was poor in cows with nonluteinized cystic follicles associated with low progesterone concentrations. However, cows diagnosed as having follicular cysts, but with progesterone concentrations of 1 ng/mL or more, responded better to fenprostalene treatment than cows with low progesterone concentrations.

It was concluded that, if correctly diagnosed, luteal cysts can be successfully treated with fenprostalene, and conception rates following treatment can be expected to be normal.

     

Treatment of post-partum anoestrous dairy cows with progesterone, oestradiol and equine chorionic gonadotropin

Anoestrus in lactating dairy cows at the start of the breeding season is a major form of reproductive wastage for seasonal dairy production based on pasture. The objective of this study was to compare the reproductive performance of anoestrous cows that were treated with a combination of progesterone, oestradiol and equine chorionic gonadotrophin either 10 days before (T-10, n = 2 19) or 16 days after (T+16, n = 229) the start of the breeding season. A higher percentage of cows in the T-10 group were detected in oestrus and inseminated during the first 6 days of breeding than those in the T+16 group (69.4% v. 26.2%. p <0.001). However, the percentage of cows detected in oestrus by Day 16 was similar between the two treatment groups (T10 v. T+ 16; 77.7% v. 76.7%). There was no difference between treatment groups in conception rate to the first (51.2% v. 59.0%) or the second insemination (50.8% v. 57.6%), in pregnancy rate over the first 49 days (74.0% v. 75.1%), in empty rate (10.0% v. 10.5%) or in the mean day of conception from the start of the breeding season (24.0 v. 25.7 days). These results suggest that, under favourable environmental conditions, treatment of anoestrous cows with the programme used in this trial can be performed 16 days after the start of the breeding season with similar results to that performed 10 days before the start of the breeding season. Further studies are needed to determine if this is the case under different environmental conditions or for other treatment programmes.     

Reproductive performance of dairy cows not detected in oestrus but with a detectable corpus luteum, in response to treatment with progesterone, oestradiol benzoate and prostaglandin F2alpha

AIM: To determine if the reproductive performance of dairy cows not previously detected in oestrus but with a detectable corpus luteum before the planned start of mating (PSM), could be improved by treatment with progesterone, oestradiol benzoate (ODB) and prostaglandin F2alpha (PGF). METHODS: Cows in 18 herds which had not been detected in oestrus, but which had a detectable corpus luteum present at veterinary examination 7 days prior to the PSM (Day -7), were allocated to 1 of 2 groups. Treated cows (n=232) received an injection of 2 mg ODB and an intravaginal progesterone releasing device (CIDR insert) on Day -7, and an injection of PGF on the day of insert removal 7 days later (Treated group). The Control group (n=243) remained untreated. Cows were mated to detected oestrus from Day 0, and conception dates confirmed by manual palpation or transrectal ultrasonography. RESULTS: During the first 7 days of mating, 37.4% of Control cows and 65.9% of Treated cows were inseminated on detection of oestrus (p<0.001). Pregnancy rates for this period were 20.4% and 36.3%, respectively (p=0.001). Conception rates to first insemination, pregnancy rates after 21 days of mating and at the end of the mating period were similar between groups (p>0.1). Median interval from the PSM to conception did not differ between treatment groups (24 and 23 days for Control and Treated, respectively, p>0.1). CONCLUSION: Treating postpartum dairy cows which had not previously been detected in oestrus but which had a detectable corpus luteum, with progesterone, ODB and PGF did not significantly improve their reproductive performance compared with no hormonal intervention. KEY WORDS: dairy cattle, postpartum, anoestrous, reproduction, progesterone treatment.