• Asian-Australasian Journal of Animal Sciences
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• v.3 no.3
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• pp.183-186
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• 1990

Monensin administered as a slow release capsule to Droughtmaster steers grazing mixed pastures containing Stylosanthes hamata or grass pastures fertilized with N, had no effect on growth rate over 111 day period. Monensin significantly increased the level of propionic acid (p<0.001) and decreased the level of butyric acid (p<0.01) in the rumen. The lack of response to monesin was partly attributed to the poor pasture conditions and growth rate of the steers during part of the experimental period. An implant of oestradiol improved growth rates during the period of poor forage quality and in the subsequent 56 days when pastures were of high quality following rain. Mean growth rates over the entire 157 days for control, monensin and monensin/oestradiol treatments were 0.37, 0.37 and 0.50 kg/d respectively. It was concluded that when pasture conditions are sufficient only for the maintenance of liveweight, production can be improved by an oestradiol implant but not by feeding an ionophore such as monensin.

• Archives of Pharmacal Research
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• v.20 no.3
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• pp.247-252
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• 1997

Perfluorotolyl (PFT)-ether and perfluorotoly-trimethylsilyl (PFT-TMS) ether derivatives of oestrone, $17{\alpha}$- and $17{\beta}$oestradiol were prepared under phase transfer conditons. The former derivatives under negative ion chemical ionization conditions gave significant ions in the mass spectrometer but $17{\alpha}$- and $17{\beta}$ -oestradiol gave poor resolution. However, the PFT-TMS derivatives of 17.${\alpha}$- and$17{\beta}$-oestradiol showed good resolution. These derivatives were used for the analysis of oestrogens in bovine aqueous humour, vitreous humour and retina. The mean $({\pm}SEM)$ concentrations of oestrone in bovine aqueous humour (n=18), vitreous humour (n=18) and bovine retina (n=4) were $0.47{\pm}0.11$, $0.46{\pm}0.14$ and $1.10{\pm}0.24 ng.ml^{-1}$, respectively. $17{\alpha}$-Oestradiol was detected in 16 out of 18 samples of bovine aqueous humour and vitreous humour and the mean $({\pm}SEM)$ concentrations were $0.30{\pm}0.10$ and $0.08{\pm}0.02 ng.ml^{-1}$, respectively. The mean $({\pm}SEM)$ concentration of 17.betha.-oestradiol in aqueous humour (n=7) and vitreous homour (n=11) $0.83{\pm}0.26 ng ml^{-1}$ and $0.39{\pm}0.09 ng ml^-1$, respectively. In retina the concentrations of both steroids were below the detection limit.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1103-1109
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• 2002

This study investigated the effect of 2-bromo-$\alpha$-ergocryptine (anti prolactin agent) on plasma levels of prolactin, oestradiol-17$\beta$ and progesterone in domestic hen during the active period of lay. Fifty healthy female White Leghorn birds were administered with anti prolactin agent (2-bromo-$\alpha$-ergocryptine, Sigma-USA., methane sulphonate salt, $C_{32}H_{40}BrN_5O_5.CH_4SO_3$) subcutaneously @100$\mu$g/kg body weight at weekly intervals from 17th to 36th week of age. Another group of fifty birds as controls were given placebo in place of bromocriptine. The level of prolactin remained lower in treated birds than in the control birds from 19 to 36 weeks of age. Level of prolactin even in the control group was found to decrease during the peak production period. Oestradiol-$17{\beta}$ and progesterone concentration in treated birds were significantly (p<0.01) higher than the controls during the treatment. Egg production, is positively correlated with oestradiol-$17{\beta}$ (r=0.02; r=0.67) and progesterone (r=0.49; r=0.90) in control and treated groups respectively where as prolactin level is positively correlated with egg production in the control birds (r=0.07). Prolactin levels were negatively correlated with egg production (r=-0.55) in treated birds; and oestradiol-$17{\beta}$ (r =-0.71; r=-0.53) and progesterone (r=-0.22; r=-0.27) respectively in control and treated groups. The total number of pause days during the treatment period decreased significantly (p<0.01) in the treated group compared to the control group. The reduction in pause days in treated group resulted in 1.76% increase in egg production over that in control group. The increase in egg laying days and the total egg production were found to be significant (p<0.01). These results indicate that a lower level of prolactin in circulatory blood enhances egg production in the domestic hen.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.4
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• pp.571-574
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• 1989

Five multiparous and four nulliparous cross-bred cows were administered s/c with oestradiol-$17{\beta}$ and progesterone 0.1 mg and 0.25 mg/kg. b.w./day for 7 days and 2 mg s/c twice daily of reserpine on days 9 to 12. Lactation was successfully induced in all animals for periods from 258 to 476 days. All animals were dried off for a minimum of 2 months. Subsequently, they were injected s/c with oestradiol valerate and hydroxyprogesterone caproate at 0.1 mg and 0.25 mg/kg. b.w./day on days 1 to 3 and 2 mg twice daily of reserpine on days 8 to 11. Lactation was successfully reinduced in all the cows for a period varying from 228 to 426 days.

• Korean Journal of Animal Reproduction
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• v.23 no.1
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• pp.53-61
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• 1999

The present study was designed to investigate the effects of gonadotrophins on in vitro growth and maturation in mouse preantral follicles. Ovaries were removed from 12-day-old ICR mice. Follicles were dissociated enzymetically in Leibovitz L-15 medium containing 1 mg/$m\ell$ collagenase and 0.2 mg/$m\ell$ DNase I. The follicles were cultured on Transwell-COL membrane inserts in six well cluster dishes for 10 days. The culture medium was $\alpha$MEM medium supplemented with 5% fetal bovine serum and FSH or HMG. After 10 days of growth in vitro, follicles were allowed to mature for 18~20 hr in medium supplemented with 1.5 IU/$m\ell$ hCG. The oocytes were then denuded of their cumulus cells and assessed maturation status. Concentrations of oestradiol and progesterone were measured with a radioimmunoassay. Oocyte diameter was determined with an ocular micrometer. The survival and Metaphase II rates of oocytes were significantly higher in FSH treatment groups than in control group (P＜0.001), but there were no differences among the groups of treated FSH concentration. The survival and Metaphase II rates of oocytes in HMG treatment group (60.9 and 40.6%) were higher than in FSH treatment group (76.6 and 48.2%) and control group (49.2 and 7.1%). The survival and Metaphase II rates of oocytes on both FSH and LH treatment groups were no differences among the ratios of FSH and LH. Diameter of oocyte was no differences among the treatment groups, but smaller than compared to in vivo grown oocyte. Through the entire culture period, secretions of oestradiol and progesterone were significantly less in control group than in HMG and FSH treatment groups. These results suggest that gonadotrophins playa key role in in vitro culture of mouse preantral follicles. Especially, addition of FSH and LH should be more effective than FSH alone.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.9
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• pp.1361-1366
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• 2007

In this project, ovarian size and activity during the peak (November-April) and the low (May-October) breeding seasons in young and adult camels were studied. Ovaries of 92 camels (Camelus dromedarius), with clinically normal reproductive tracts, aged 3-15 years and slaughtered at Faisalabad or Lahore abattoirs over a period of 24 months, were collected. Jugular blood was collected from each animal before slaughter; the serum was separated and analyzed for oestradiol concentration. The size (length, width and thickness) and weight of each ovary were measured. Grossly observable Graafian follicles were counted and their diameter was measured using Vernier Calipers. The camels having ovaries presenting follicles more than 5 mm in diameter were taken as having active ovaries. The results showed that ovarian length, width and weight were significantly higher (p<0.05) during the peak than the low breeding season. The percentage of active ovaries was also significantly higher (p<0.01) during the peak than the low breeding season. However, the effect of season on ovarian thickness was non-significant. Similarly, the ovarian length, width, thickness, weight and activity did not vary significantly between young (3-7 years old) and adult (8-15 years old) animals. Serum oestradiol concentrations were significantly higher (p<0.05) during the peak ($67.70{\pm}1.36$ pg/ml) than the low breeding season ($15.25{\pm}1.54$ pg/ml). It was concluded that in Pakistani camels ovarian size and activity were higher during the peak than the low breeding season. However, age of the camel (from 3 to 15 years) had no effect on these parameters.

• Korean Journal of Animal Reproduction
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• v.17 no.1
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• pp.69-74
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• 1993

This study was investigated to examine the effect of conditioned medium from bovine oviductal cell(BOEC) in the co-culture system with BOEC on in vitro development of in vitro produced bovine embryos. Oocyte-cumulus complexes were cultured for 24 hrs in TCM-199 supplemented with 10% fetal calf serum, 1$\mu\textrm{g}$/ml FSH and 21U hCG, 1$\mu\textrm{g}$/ml oestradiol-17$\beta$ at 39$^{\circ}C$ under 5% CO2 in air. In vitro fertilization was performed with epididymal sperm and heparin (10$\mu\textrm{g}$/ml, 15min.) or caffeine(2.5mM)-treated spermatozoa. Oocytes were incubated with 1$\times$106 spermatozoa/ml for 18 hrs and then cultured in various culture system for 7 days. The development rates of 16-cell or blastocyst stages were recorded on 4, 7 days, respectively, after incubating. The proportions ofembryonic development into molulae and blastocysts were higher in cumulus cell co-culture(23.4%) and BOEC co-culture(34.3%) than in M199-FCS(6.1%). Similarily, the development rates into molulae and blastocysts were significantly higher in BOEC-conditioned medium than those in M199-FCS. Therefore, it is suggested that BOEC co-culture and BOEC conditioned medium increase significantly the development of in vitro produced bovine embryos in in vitro system.

• Journal of Veterinary Clinics
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• v.1 no.1
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• pp.25-31
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• 1984

The effects of progesterone releasing intravaginal device (PRID) on the fertility levels in dairy cows were studied in 2 experiments. In experiment I, 70 lactating cows at 45 days postpartum were allotted to 3 groups and the treatments imposed were either： 1: Untreated control, 2: PRID with a capsule containing long of oestradiol benzoate (ODB) attached, inserted for 12 days, 3: PRID inserted for 12 days with long of prostaglandin F$\_$2${\alpha}$/ administration 24 h before PRID removal. Treated cows were inseminated 56 h after PRID removal and at an observed oestrus during the subsequent 48-day period. The control group was inseminated at an observed oestrus during this 60-day period. In experiment II, 60 ovarian disorder cows were divided into 5 groups and PRID+ODB inserted for 12 days. 1: atrophied ovary, 2: smooth ovary, 3: persistent corpus luteum, 4: follicular cyst, 5: luteal cyst. Treated cows were inseminated 56 h after PRID removal and at an observed oestrus over a period from the first insemination to 46 days. The results obtained were as follows: 1. The device produced a vaginal discharge in some animals. In experimenet I : 2. For treatments 2 and 3, respectively, conception rates to the fixed time insemination were 45% and 52%. 3. The conception rates of cows inseminated to the fixed time insemination and at an observed oestrus during a 60-day period were 65%, 86% and 91% for control, treatment 2 and 3, respectively. 4. Mean interval from calving to conception and inseminations per conception were 133, 91 and 86 days and 2.4, 2.1 and 1.9 for control, treatments 2 and 3, respectively. In experiment II； 5. The conception rates to the fixed time insemination for each group 20, 50, 70, 20 and 50%, respectively. 6. The total conception rates for the 48 days period of each group were 60, 70, 100, 60 and 90%, respectively. 7. The inseminations per conception of each group were 2.8, 2.1, 1.4, 2.7 and 1.9, respectively.

• Korean Journal of Animal Reproduction
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• v.17 no.4
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• pp.271-278
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• 1994

The aim of this study was to compare the two culture systems 1) co-culture with cumulus cells and 2) chemically defined medium supplemented with amino acids (CR1aa) and fetal calf serum (FCS) of in vitro produced bovine embryos from follicular oocytes in vitro. Bovine follicular oocytes were collected from ovaries of slaughtered cows and matured in TCM199 supplemented with 10% FCS and hormones (1$\mu\textrm{g}$/ml FSH-P and 1$\mu\textrm{g}$/ml oestradiol-17$\beta$)24 hours at 39$^{\circ}C$ under 5% CO2 in air. The capacitation of spermatozoa from ejaculated or frozen bull semen was induced by centrifugation through Percoll density gradient (45%, 90%). Then capacitated spermatozoa (1$\times$106/ml) were inseminated into 50${mu}ell$ droplet containing matured follicular oocytes and incubated for 40~42 hours. Cleaved embryos of 2~4cell stage were transferred to the co-culture with cumulus cells and/or CR1aa medium supplemented with FCS. In semen source, the developmental rates to the blastocyst and the hatched blastocyst stages were higher in ejaculated semen(27.6% and 14.9%) than those of frozen-thawed semen(18.3% and 11.8%), respectively. In two culture systems, the proportions of embryonic development upto the blastocysts and the hatched blastocysts were higher of CR1aa medium (22.1% and 12.1%) than those of cumulus cell co-culture (16.8% and 5.1%), respectively. The number of cells in exapnded blastocysts was slightly higher in cumulus cells co-culture (122.6$\pm$8.5) than that in CR1aa medium (117.9$\pm$5.9). The present results indicated that the early development of in vitro produced bovine embryos can be maintained efficiently in CR1aa medium as well as in co-culture with cumulus cells.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1566-1573
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• 2006

The study was conducted on 30 true acyclic Sahiwal cows (15 cows, ${\geq}90$ days postpartum; 15 postpubertal heifers, ${\geq}30$ months of age) and a similar 20 untreated controls (10 cows, 10 heifers). An 'Eazi' breed Controlled Internal Drug Release (CIDR) device (containing 1.38 g progesterone) was inserted intravaginally for 7 days (days 0 to 7) followed by 500 IU eCG i.m. at CIDR removal in all the treated animals. Heifers also received 5 mg oestradiol valerate i.m at CIDR insertion. The reproductive performance of these animals was recorded in terms of oestrus induction response, conception and pregnancy rates. Plasma progesterone ($P_4$) and oestradiol-$17{\beta}$ ($E_2$) profiles of 4 representative animals from each treatment group before, during and after CIDR treatment were also monitored. An oestrus induction response of 100% was observed in treated cows and heifers. The majority of cows (53.3%) and heifers (60%) were induced to oestrus within 24-36 and 36-48 h, respectively after CIDR withdrawal; with mean intervals of $44{\pm}3.18$ and $48{\pm}2.35h$, respectively. The conception rate at induced oestrus was higher in cows (40%) than heifers (20%). The final pregnancy rates after 2 subsequent oestruses were 80 and 60% in cows and heifers, respectively (overall 70% for all treated animals). In comparison, only 10% of control animals (2 cows only, 2/20) showed oestrus and become pregnant (10%) during theentire study period. The pretreatment (day 0) mean plasma P4 levels were statistically (p>0.05) similar in cows and heifers ($0.40{\pm}0.04$ and $0.49{\pm}0.11ng/ml$, respectively). The peak $P_4$ levels were observed on day 1 in cows ($13.94{\pm}1.41ng/ml$) and day 2 in heifers ($19.15{\pm}3.30ng/ml$) with a progressive decline up to the day of CIDR withdrawal ($3.35{\pm}0.92$ and $8.79{\pm}1.71ng/ml$, respectively). Mean $P_4$ levels on day 9 and 10 in cows and heifers did not differ significantly from their respective day 0 values and the lowest values were recorded on day 10 both in cows and heifers ($0.13{\pm}0.03$ and $0.14{\pm}0.02ng/ml$, respectively). Wide variations in individual pretreatment $E_2$ levels were observed both in the cows (range = 4-26, mean = $13.00{\pm}4.65pg/ml$) and heifers (range = 10-14, mean = $11.50{\pm}0.96pg/ml$). Thereafter also, $E_2$ levels in cows showed variation and reached a peak level ($53.50{\pm}2.99pg/ml$) on day 8. In heifers, peak mean $E_2$ level ($111.25{\pm}39.81pg/ml$) was recorded on day 1, followed by a non-significant decline on day 2, a significant fall on day 6 and a non-significant increase on day 9 and 10. However, mean $E_2$ levels on days 7 (p<0.05), 8 and 9 (p<0.01) were significantly higher in cows compared to heifers. The post-CIDR withdrawal mean highest $P_4$ and lowest $E_2$ levels coincided with the period when the majority of animals were induced to oestrus. CIDR and eCG treatment resulted in effective induction of oestrus with satisfactory pregnancy rates in true acyclic Sahiwal cows and heifers.