Partial budgeting assessment of the treatment of pyometra, follicular cysts and ovarian inactivity causing postpartum anoestrus in dairy cattle

A total of 412 multiparous German Holstein cows were screened for postpartum pyometra, follicular cysts and ovarian inactivity to assess economic and productivity losses in relation to pharmaceutical expenditures. Our results show that cows treated for pyometra with prostaglandin f2 alpha (PGF2α) and oxytetracycline had significantly (P < 0.05) greater total and net returns than untreated cows or those treated with PGF2α + cephapirin or PGF2α alone. Milk yields from untreated cows affected by follicular cysts were significantly (P < 0.05) lower than the yields from cows treated with gonadotrophin-releasing hormone (GnRH)− and GnRH + PGF2α. In addition, the use of GnRH to treat cows with ovarian inactivity resulted in significantly (P < 0.05) lower costs and greater total and net return values compared to untreated controls.     

Effect of a single injection of progesterone on ovarian follicular cysts in lactating dairy cows

The objective of this experiment was to evaluate the effect of a single injection of progesterone on the lifespan of ovarian follicular cysts and to examine the fate of follicles that mature following treatment. Lactating Holstein and Jersey cows with ovarian follicular cysts were identified by rectal palpation. The ovaries of cystic cows were then examined by transrectal ultrasonography three times weekly to monitor formation of new follicular cysts. Cows with newly formed follicular cysts were treated either with a single injection of progesterone (200 mg, IM, n = 11) or corn oil vehicle (n = 7). Venous blood samples were collected daily for quantification of progesterone. Blood sampling and ultrasonography continued until ovulation or a new follicular cyst formed. Treatment reduced the lifespan of the cyst by 12 days, from 29.8 +/- 2.3 days in control cows to 17.2 +/- 1.8 days in progesterone-treated cows (P = 0.01). Progesterone treatment also tended to alter the frequency of subsequent follicular events. Ovulation occurred in 4/11 cows that were treated with progesterone whereas none of the vehicle treated cows ovulated (P = 0.07). In conclusion, a single injection of 200mg of progesterone, administered early in the life of an ovarian follicular cyst, shortened its lifespan and in some cases was followed by ovulation of a new follicle.     

Clinical response of ovarian cysts in dairy cows after PRID treatment

We investigated the therapeutic effects of a progesterone releasing intravaginal device (PRID) on cystic ovarian disease (COD) and reproduction performance of cows. The possible influence of PRID on metabolic and/or health status was also examined. A total of 40 Holstein-Friesian cattle, with ovarian cystic structures, > or =2.5 cm in diameter, persisting for more than 7-14 days, without a corpus luteum (CL) were used for the study. PRID or placebos were inserted into the vagina for 12 days. Five animals lost the intravaginal device before removal and one was culled. Based on plasma progesterone concentration on the day of treatment, 20 (17 PRID and 3 placebos) of the remaining 34 cows had follicular cysts (progesterone < or =1 ng/ml) and 14 (10 PRID and 4 placebos) had luteal cysts (progesterone >1 ng/m l). Fourteen (82%) of the PRID-treated follicular cystic cows responded with formation of a CL within 14 days after treatment, and an overall conception rate of 53.8%. Likewise, 70% of the treated luteal cystic cows responded with CL formation and 71.4% conception rate. No significant differences were observed in hematocrit (Ht), white blood cell count and serum levels of glucose, blood urea nitrogen, aspartate aminotransferase, and alanine aminotransferase, between the day of PRID insertion and removal, in animals with follicular and luteal cysts. PRID treatment resulted in ovulation 2-4 days later and formation of a CL in cows that recovered.     

Transrectal ultrasonic diagnosis of ovarian follicular cysts in goats and treatment with GnRH

Cystic ovarian disease is an important cause of reproductive failure. The objective of this study was to evaluate transrectal ultrasonography as a diagnostic tool and gonadotropin-releasing hormone (GnRH) as a therapeutic approach for ovarian follicular cysts in goats. Goats were considered to have a follicular cyst(s) if a non-echoic structure >10 mm in diameter was detected in the absence of corpora lutea (CL) in three ultrasonic examinations performed at 5-day intervals. After diagnosis (Day 0), goats with ovarian follicular cysts (n = 5) were treated with a single bolus injection of 10.5 microg synthetic GnRH followed by administration of 125 microg prostaglandin F2alpha (PGF2alpha) 10 days later. Five blood samples were collected at 5-day intervals for determination of progesterone and estradiol-17beta. For detection of LH surge, blood samples were collected every 2 h. Ovulation rate was determined and pregnancy was confirmed by transrectal ultrasonography. The results showed that transrectal ultrasonography is reliable for diagnosis of ovarian follicular cysts and the mean diameter of the follicular cysts was 12.6 +/- 0.4 mm. Plasma concentrations of progesterone and estradiol-17beta at the time of diagnosis of follicular cysts (Day 0) were 0.7 +/- 0.2 ng/ml and 12.7 +/- 0.9 pg/ml, respectively. The concentration of progesterone increased to 4.0 +/- 0.5 ng/ml 10 days after administration of GnRH indicating luteinization of the ovarian follicular cysts concomitant with a decrease in the concentration of estradiol-17beta (3.5 +/- 0.4 pg/ml). Administration of GnRH to cystic goats resulted in a surge of LH within 2 h of treatment. The interval from PGF2alpha injection to the preovulatory LH surge was 62.8 +/- 1.4 h. All goats exhibited estrus 55.2 +/- 2.3 h after PGF2alpha injection and four goats out of the five ovulated. The ovulation rate was 1.5 +/- 0.3. In conclusion, results of this study suggest that transrectal ultrasonography is a reliable tool for diagnosis of ovarian follicular cysts. In addition, GnRH can be used to effectively treat ovarian follicular cysts in goats with 80% success rate.     

Three cases of ovarian epidermoid cysts in cattle

Three cases of bovine, ovarian epidermoid cysts were diagnosed as unilateral benign lesions in three out of 1,971 cows at slaughter. A stratified, cornifying, and squamous epithelium without associated skin adnexal structures or tissues from other embryonic tissue layers lined the cysts. The cysts were small, usually multiple, and contained keratin debris. Macroscopically, they resembled abscesses. These are benign, congenital lesions that are a separate entity from dermoids and teratomas, and they appear to have a higher incidence in cattle with Bos indicus breeding.     

Diagnosis of luteal and follicular ovarian cysts by palpation per rectum and linear-array ultrasonography in dairy cows.

The purpose of this study was to determine and compare the accuracy of palpation per rectum and linear-array ultrasonography for diagnosing follicular vs luteal ovarian cysts in cows. Forty-seven examinations of ovarian cysts from 28 cows were diagnosed by palpation per rectum as either a firm, thick-walled structure (luteal cyst) or a soft, thin-walled structure (follicular cyst) during weekly herd examinations. The ovaries of each cow were then examined by ultrasonography. Ultrasonograms of cysts greater than 25 mm in diameter were diagnosed as luteal or follicular cysts and were recorded on videotape for evaluation by a second clinician. Serum progesterone concentrations at the time of examination were determined by radioimmunoassay and used to classify luteal (greater than 0.5 ng/ml) or follicular (less than or equal to 0.5 ng/ml) cysts. Selection of this discriminatory level was based on response of a proportion of cows with luteal cysts that were given 25 mg of prostaglandin F2 alpha at the time of diagnosis by ultrasonography. Sensitivity and specificity of palpation per rectum for diagnosis of type of ovarian cyst were low (43.3 and 64.7%, respectively). In contrast, sensitivity and specificity of ultrasonography were considerably higher (86.7 and 82.3%, respectively). Agreement between the 2 methods of diagnosis was 57.4%. Overall agreement between the 2 clinicians' diagnoses by ultrasonography was 85.1%. On the basis of our findings, we confirm that luteal and follicular cysts cannot be accurately differentiated by palpation per rectum alone. These data suggest that linear-array ultrasonography is more effective than palpation per rectum for diagnosing type of ovarian cyst in cows.     

Treatment of cystic ovarian disease in dairy cattle

Fourty-four Holstein Friesian cows diagnosed as having ovarian follicular cysts from rectal palpation of the ovaries and observation of estrous behavior were used for the present experiments. Of the 16 cows injected intramuscularly (i.m.) with 110 mg of depot-progestins containing 100 mg of 17alpha-hydroxyprogesterone caproate and 10 mg of progesterone in oil, 8 cows responded with conception with 103 +/- 53 days in average after the treatment. The 8 cows not responding to depot-progestins were injected i.m. with 6,000 MU of HCG on the 10th day after the treatment. As a result, 2 cows of them conceived within 72 days in average after the initial treatment. Of the other 16 cows injected i.m. with 100 mg of progesteron in oil, 3 cows conceived. Interval between the treatment and conception was 36 +/- 9 days in average. In the 11 cows which failed to respond to progesterone treatment, an intramuscular injection of 6,000 MU of HCG on the 5th day after treatment resulted in conception of 7 cows within 42 +/- 10 days in average after the first treatment. Of the remaining 12 cows which received an i.m. injection with 10,000 MU of HCG, 4 cows responded with conception with 64 +/- 51 days in average after treatment. No remarkable rise in serum progesterone levels was observed either 10 days after depot-progestins injection or 5 days after progesterone treatment. Serum progesteron levels increased distinctly after HCG injections. The combined treatment with 100 mg of progesterone and 6,000 MU of HCG at 5 days interval gave the most successful results and this treatment was effective even when performed long after calving. Thus this method of treatment of cystic ovarian disease may be recommended for practical application.     

Ovarian follicular cysts in dairy cows: an abnormality in folliculogenesis

Ovarian follicular cysts are a major reproductive problem in lactating dairy cows. The primary physiological defect leading to the formation of ovarian follicular cysts is a failure of the hypothalamus to trigger the preovulatory surge of luteinizing hormone (LH) in response to estradiol. The factor responsible for this hypothalamic defect may be progesterone. Intermediate levels of progesterone have been shown to prevent ovulation and promote persistence of dominant follicles in normal cycling cows. Recently, we found that 66% of cows with ovarian follicular cysts had progesterone concentrations in an unusual, intermediate range (0.1-1.0 ng/mL) at the time of their detection. A majority of new follicles (76%) that develop in the presence of these intermediate progesterone concentrations became cysts. Only 10% ovulated. Based on these observations, a novel model for the formation and turnover of ovarian follicular cysts is proposed.     

Clinical response of dairy cattle with ovarian cysts to single or repeated treatments of gonadotropin-releasing hormone.

Two hundred twenty-five dairy cows with ovarian cysts were treated with 100 microgram of gonadotropin-releasing hormone (GnRH). Cows failing to recover were retreated with a second or third dose of GnRH. Clinical recovery following 1st, 2nd, and 3rd treatments was 76% (170/225), 78% (43/55), and 66% (8/12), respectively. Of the 221 cows that recovered, 184 eventually became pregnant. The remaining 41 cows were culled primarily as problem breeders. First-service conception rate was 49%. More ovarian cysts were detected in herds examined at 2-week intervals than in herds examined at 4-week intervals. The increased diagnosis of ovarian cysts may have been related to detection of cysts prior to spontaneous recovery that occurs in some cases. Clinical recovery from ovarian cysts was lower in herds examined at 2-week intervals following treatment, compared with those examined at 4-week intervals. The GnRH-induced luteinization of ovarian cysts and response to treatment was more difficult to judge at 2 weeks than at 4 weeks.     

The effect of estradiol cypionate (ECP) on ovarian follicular development and ovulation in dairy cattle.

The efficacy of estradiol cypionate (ECP) for synchronizing ovarian follicular development was determined in lactating Holstein-Friesian cattle. In Experiment 1, 13 cattle were given simultaneous intramuscular (i.m.) injections of 100 mg progesterone and 0 (control), 0.5 or 1.0 mg ECP on Day 3, after a synchronized ovulation (Day 0). Maximum diameter of the dominant follicle of Wave 1 was significantly larger in control cattle than in those given 0.5 or 1.0 mg ECP (means: 15.7, 13.2, and 12.9 mm, respectively). Mean day of emergence of Wave 2 was significantly later in controls than in those given 1.0 mg ECP, with the 0.5 mg group intermediate (Days 10.2, 8.8 and 9.5, respectively). In Experiment 2, 14 cattle were given a CIDR-B and IM injections of 1 mg ECP and 50 mg progesterone without regard to stage of cycle (treatment = Day 0). On Day 8, the CIDR-B was removed and 500 micrograms cloprostenol injected, IM. Mean days of wave emergence (Day 3.4; range: -2 to 7) and ovulation (Day 12.1; range: 10 to 14) indicated that ECP had limited efficacy for synchronizing follicular development and ovulation in dairy cattle when given at random stages of the estrous cycle.     

Factors that affect ovarian follicular dynamics in cattle.

Studies of ovarian follicular dynamics in cattle may lead to methods for improving fertility, for synchronizing estrus with more precision, and for enhancing superovulatory responses. Within an estrous cycle, two or three large (> 10 mm) follicles develop during consecutive waves of follicular growth. The last wave provides the ovulatory follicle, whereas preceding wave(s) provide follicles that undergo atresia. The life span of large follicles seems to depend on the pulsatile secretion of LH; decreased frequency of LH pulses results in atresia of large follicles. Aromatase activity in the walls of the largest follicles is greatest during the first 8 d of the estrous cycle and decreases by d 12. Steroidogenesis of the largest and second-largest ovarian follicles differs on d 5, 8, and 12 of the estrous cycle. Follicular dynamics are altered by negative energy balance and lactation. The number of large follicles and concentration of estradiol during the preovulatory period differs between postpartum lactating and nonlactating cows. Dietary fats stimulate follicular growth when they are fed to increase energy balance. Administration of bovine somatotropin decreases energy balance and has a differential effect on ovarian follicular responses; growth of the largest follicle does not change, but growth of the second-largest follicle is stimulated by somatotropin. Studies of follicular dynamics in lactating cows demonstrate changes in ovarian function associated with energy balance that may be related to inefficient reproductive performance of cows producing high yields of milk.     

Relationship of fertility to ovarian follicular waves before breeding in dairy cows

Cows with two waves of follicular growth during the estrous cycle yield follicles that are older and larger at ovulation compared with cows having three waves. The objectives of the current research were 1) to compare fertility in cows with two or three follicular waves and 2) to examine associations between luteal function, follicular development, and fertility after breeding. Follicular waves were monitored by ultrasonography during the estrous cycle before insemination in 106 dairy cows. Fewer cows had three follicular waves before next estrus and ovulation than two waves (P < 0.01; 30% vs 68%, respectively), but pregnancy rate was higher (P = 0.058; 81 vs 63%, respectively). Cows with two waves had shorter estrous cycles (P < 0.01), with the ovulatory follicle being both larger (P < 0.05) and older (P < 0.01). In cows with three waves, luteal function was extended (P < 0.05) and the peak in plasma progesterone occurred later (P < 0.05) in the estrous cycle compared to two wave cows. Considering cows that became pregnant, luteal phase length was shorter (P < 0.05) during the estrous cycle preceding insemination than for nonpregnant cows. In conclusion, fertility was greater in lactating cows inseminated after ovulation of the third-wave follicle that had developed for fewer days of the estrous cycle as compared with two-wave cows.     

The effect of repeated follicular puncture on ovarian function in dairy heifers

Three dairy heifers were examined during three consecutive oestrous cycles (control period, CP). Subsequently, the animals were subjected to 4 and then 5 weeks of twice-weekly ovum pick-up (OPU) (FPP1 and FPP2, respectively) with a recovery period (RP) of two consecutive oestrous cycles between FPP1 and FPP2. After FPP2, the animals were slaughtered and the ovaries were macroscopically examined. Throughout, ovarian activity was monitored by transrectal ultrasonography and concentrations of plasma progesterone. During CP, all the heifers showed normal cyclicity. During FPPs, the heifers occasionally presented oestrous activity. Corpus luteum (CL)-like structures developed from punctured follicles with diameters and life-spans varying from smaller and shorter than those in the CP (P > 0.05) to equal to those in the CP. There was a tendency for a lower number of emerging and punctured follicles in the presence of a CL-like structure. Subsequently to FPP1, all heifers regained normal cyclicity. A thickening of the ovarian tunica albuginea and a slight hardening of the ovaries were found postmortem. In conclusion, dairy heifers can occasionally show cyclic activity and form CL-like structures during twice-weekly OPU. Further, OPU did not seem to cause any major negative effects on ovarian structure and subsequent ovarian function.