Effect of time of eCG administration on the fate of ovarian follicle in Holstein heifers

The objective of this study was to investigate the effect of equine chorionic gonadotropin [eCG] on ovarian follicles at three stages of development [emergence, dominance and early static phases] during the first follicular wave [FFW] in Holstein heifers. Heifers [n=20] were randomly assigned into four experimental groups [n=5 in each group]. Heifers received eCG [500 IU; Folligon®; Intervet, Holland; i.m] a] on the day of follicle emergence [day of ovulation; group 1], b] on the dominant phase [dominant follicle [DF]: the first day in which follicle was observed at >/= 10 mm; group 2, and c] on the early static phase [group 3] of the FFW. Control group heifers did not receive any treatment. Daily ultrasonography was conducted to monitor ovarian structure throughout estrous cycle. All treatment group heifers, regardless of the stage of follicle development, displayed follicle growth after eCG injection. Administration of eCG, in group 1, hastened DF detection and induced co-dominant follicles; whereas, in groups 2 and 3, it delayed DF regression, and increased cycle length compared to control. In all treatment group heifers, DF was present 84 h after eCG injection. Maximum diameter of corpus luteum was larger in eCG treated groups compared to control [P<0.05]. In conclusion, depending on the time of eCG administration throughout the FFW [emergence, dominant and early static phases], co-dominancy, maintenance of DF, enhancement of follicle and corpus luteum growth and increase in estrous cycle length could be observed in Holstein heifers

Clinical and paraclinical evaluation of partial nephrectomy using laparoscopy and open surgery in dogs: new suturing technique

Partial nephrectomy, using open surgery or laparoscopy, is a standard surgical approach to treat renal disorders. The objective of this study was to compare and evaluate the feasibility and safety of laparoscopic partial nephrectomy using figure eight ligation technique. Mixed-breed dogs were randomly dedicated for partial nephrectomy using laparoscopy [n=6] and open surgery [n=6]. During 30 days after operation, clinical, hematological and ultrasonographic findings, intra- and post-operative complications, operation and ischemia times, urine analysis and incision length were recorded. Operations were performed successfully and dogs recovered without serious complications. All clinical and hematological findings were within normal range. Comparing two experimental groups, operation time and length of incisional scar were longer in open surgery and ischemia time was longer in laparoscopy [P<0.05]. In conclusion, using figure eight ligation, laparoscopy seems to be safer, more feasible, less time consuming in association with less bleeding for partial nephrectomy compared with conventional open surgery in dog

Replacement of salamon with shotor diluent and egg yolk with low density lipoprotein for chilled storage of ram semen

The present study investigated the possibility of replacing salamon with modified shotor diluent [MSD] and egg yolk [EY] with low density lipoprotein [LDL] for chilled storage of ram semen. Good quality semen [>80% progressive forward motility [PFM] of sperm] from 3 fertile rams was collected using an artificial vaginaandpooled for each experiment. Low density lipoprotein was extracted from fresh EY. In experiment 1, semen was divided into 2 fractions and extended in MSD or salamon. In experiment 2, semen was assigned into 5 fractions and extended in MSD supplemented with 12 and 15% EY or 3, 5 and 8% LDL. In experiment 3, semen was divided into 2 fractions and extended in MSD supplemented with 12% EY or 5% LDL. Viability of sperm was assessed at times 0 [immediately after semen dilution], 2 or 4 [at 4°C] and up to 72 h after semen dilution. Data was analyzed using General Linear Model [GLM] procedure, including repeated measures. In experiment 1, the viability of sperm was similar in two diluents [P>0.05]. In experiment 2, PFM of sperm was similar among groups at the time of dilution [P>0.05]; but remained elevated in 5 and 8% LDL compared to other groups afterward [P<0.05]. In experiment 3, PFM of sperm was superior at 48 and 72 h after dilution in 5% LDL compared to 12% EY [P<0.05]. In conclusion, MSD supplemented with 5% LDL is a suitable diluent for ram fresh semen preserved at 4°C for 72 h. Key words: Ram, Semen preservation, Low density lipoprotein, Diluent

Ovulatory response of different GnRH analogues and subsequent corpus luteum lifespan in the presence of norgestomet in Holstein heifers

This study investigated the effect of GnRH analogues on inducing ovulation of dominant follicle [DF] and subsequent corpus luteum [CL] lifespan in the presence of norgestomet implant in Holstein heifers. On day 6 to 8 of the estrous cycle [day 0 of the experiment], all heifers [n=15] received norgestomet implant followed by prostaglandin injection on days 0 and 1. On day 4, group 1 [n=4] and 2 [n=4] heifers received 12.5 and 25 microg Alarelin, respectively. Heifers in group 3 [n=3] received 10 microg Buserelin. Heifers in control group [n=4] did not receive any further treatment. Norgestomet was removed on day 8 in the treatment group and kept throughout the experiment in control group. From day 0, blood sampling and ultrasonography were performed. Heifers were monitored after inducing ovulation for 2 consecutive estrous cycles. DF ovulated within 33 h after GnRH injection. Progesterone started to rise on day 3 and declined on day 7.45 +/- 0.28 after GnRH injection. Heifers in treatment groups displayed estrus 7.73 +/- 0.24 days after GnRH injection followed by spontaneous ovulation. The lifespan of CLs were 5.36 +/- 0.28 and 16.9 +/- 0.37 days after inducing ovulation of DF in the presence of norgestomet and following spontaneous ovulation, respectively [P<0.05]. In conclusion, the half dose of Alarelin induced ovulation of DF and the presence of single norgestomet implant after ovulation may be associated with short luteal lifespan

[Postpartum ovarian activity in primiparous Holstein dairy cows]

Postpartum anestrus is a major problem in primiparous dairy cows. The objective of this study was to investigate postpartum ovarian activity in primiparous Holstein dairy cows. Seven primiparous Holstein dairy cows were monitored for ovarian activity using a combination of ultrasound examination and alteration in progesterone concentrations. Daily blood sampling and ultrasound examination were conducted starting from day 6 until the third ovulation postpartum. First wave dominant follicles [>/= 10 mm in diameter] were detected on day 11.5 +/- 1.48 postpartum. This follicle did not ovulate in any of the experimental cows. Moreover, none of the cows ovulated within 20 days postpartum. There was no difference in the follicular growth rate and the diameter of ovulatory follicles between the first, the second and the third ovulations postpartum [p>0.05]. Interval from calving to the firstpostpartum ovulation was 48.1 +/- 6.89 days. Mean diameter of corpus luteum and progesterone concentrations of the first cycle [18.8 +/- 0.94 mm and 2.0 +/- 0.24 ng/mL] were significantly less than those of the second cycle [24.0 +/- 0.89 mm and 3.6 +/- 0.36 ng/mL; p<0.05]. In conclusion, increased interval from parturition to the first ovulation is not due to the delayed or lack of the first wave dominant follicle formation after parturition; but is due to the regression of this follicle

Effects of diets enriched in different sources of fatty acids on reproductive performance of Zel sheep

The present study evaluated the effects of diets enriched in saturated and polyunsaturated fatty acids [n-3 and n-6] on reproductive indices, metabolic hormones and metabolites prior to ram introduction in oestrus synchronized ewes. Zel ewes [n=188] were assigned to 4 groups. Ewes in the control group [CON] did not receive fat. Ewes in the 3 other groups received 3% oil/DM/day of palmolein oil [PLM], safflower seed [SAF], or flaxseed [FLX]. Fat supplementation was carried out for 31 days [day 0 = initiation of fat supplementation]. Oestrus was synchronized using CIDR for 14 days starting from day 16 of fat supplementation. Rams were introduced 24 h after CIDR removal. Blood samples were collected on days 0, 30, and 39. There was no difference in oestrus expression and mating parameters among groups. There was no difference in non-esterified fatty acids [NEFAs], insulin and insulin-like growth factor-1 [IGF-1] between day 0 and day 30 among groups. However, changes in cholesterol and LDL concentrations during the same occasions were greater in PLM, SAF, and FLX groups than in CON [P<0.05]. There was no difference in reproductive indices, including: fertility rates, prolificacy and sex ratio of lambs among groups. In conclusion, diets enriched in n-6 and n-3 polyunsaturated fatty acid prior to mating did not affect reproductive performance, insulin, IGF-1 and progesterone in Zel sheep

Effect of systemic antibacterial administration during prepartum period on coagulase negative Staphylococcal intramammary infection in Holstein Heifers

A total of 183 coagulase negative Staphylococcal infected quarters and 64 uninfected quarters were randomly allotted to 4 experimental groups: infected quarters that did not receive any treatment [positive control group; n = 60]; infected quarters that received Tylosin [n = 61] or Cefquinome [n = 62] and also uninfected quarters that did not receive any treatment were considered as negative control group [n = 64]. Treated heifers received Tylosin or Cefquinome 10 to 14 days before the expected calving date. The bacteriological cure rate based on sampling obtained 3 days after calving was significantly higher [P<0.01] in mammary glands treated with systemic Tylosin [85.3%] than in the positive control group and mammary glands treated with systemic Cefquinome [69.4%]. At the same time Tylosin treated heifers had significantly lower [P<0.01] somatic cell count scores compared to the positive control and Cefquinome groups. With the exception of one heifer that calved 8 days earlier than the expected calving date, there was no detectable antibiotic residues in the milk of the treated heifers on the 3rd day of lactation

[ effect of norgestomet implant on follicle development in bactrian camel]

Progestagens have been used in order to control follide wave dynamics in camelids, however, the results are contra versial. The purpose of this study was to investigate the effect of single norgestomet implant on ovarian follicle development in Bactrian camel. Bactrian camels [n=8; 6-14 years old] were assigned randomly to two groups. Norgestomet treated group [n=4] received one implant of norgestomet under the skin of ear for 10 days [Day 0= Day of implant insertion]. Camels in Control group [n=4] did not receive any treatment. Daily ultrasound examination using trans-rectal linear probe was conducted to determine ovarian follicle status. Mature follicle was defined as a growing follicle at the size of 13-17mm in diameter. In both groups, there was a female with a persistent follicle throughout the experiment and a new emergence of follicle wave on Day 6-7 of the experiment. The latter follicle did not reach mature size on Day 10 of experiment. In both groups, there was a female with growing follicle during the experiment that became at the range of mature size at the termination of study. In both groups, there was a female with a regressing follicle throughout the experiment and a growing follicle which become mature during 10 days of treatment. One female in Control group had a persistent follicle throughout the experiment and a new emergence on Day 9. One female in Norgestomet treated group, had a persistent follicle during experiment and a growing follicle that ovulated spontaneously between Days 9 and 10 of experiment. In conclusion, single Norgestomet implant for 10 days does not regulate ovarian follicle development in Bactrian camel

effect of LH and GnRH analogues on induction ovulation in Bactrian camel [Camelus bactrianus]

Ovarian follicle response and corpus luteum formation following induction of ovulation using gonadotropin-releasing hormone [GnRH] analogues and luteinizing hormone [LH] in Bactrian camel were characterized. Bactrian camels with a mature follicle [13-19.6 mm] received: 1] natural porcine LH [25 mg, IV, n = 4], 2] Buserelin [20 microg, IV, n = 4] and 3] Alarelin [25 microg, IM, n = 4]. Daily ultrasonography and blood samplings were conducted between day -3 and +15 of the experiment [day 0 = Induction of ovulation]. Data were analyzed by univariat analysis with repeated measures analysis included in the model. Following treatment, mature follicle ovulated within 2 days and a new follicle wave emerged after 2-3 days. New mature follicle reached a size of 13.5 +/- 0.14 mm by day 12. Corpus luteum was detected on day 6 and reached the maximum size of 19.73 +/- 0.81 mm on day 9. Progesterone concentration initiated to increase on day 5, reached maximum concentration on day 9 and decreased significantly on day 11. In conclusion, due to the lack of significant difference among treatment groups [P>0.05], Alarelin may be considered as a drug of choice for inducing ovulation in Bactrian camel because of its effectiveness, simple route of administration [IM vs. IV], lower price, and local availability

Successful cryopreservation of in vitro derived bovine blastocysts in microcapillary pipette tips

The open pulled straw has been used effectively to vitrify preimplantation embryos because of geometric features that allow rapid rates of temperature exchange. One possible inexpensive alternative to the open pulled straw are commercially-available microcapillary pipette tips commonly used for electrophoresis. The main purpose of this study was to compare the survival rates of in vitro produced blastocysts following vitrification in microcapillary pipette tips and open pulled straws. Two experiments were conducted to investigate the effect of type of carrier, age of exp and ed blastocyst, and addition of beta-mercaptoethanol to post-warming culture medium on survival of vitrified in-vitro derived blastocysts. Exp and ed blastocysts [Day 7, 0900H and 1900H after insemination; insemination = Day 0 at 0900H] were vitrified while loaded randomly in groups of 4-10 into open pulled straws or pipette tips. Following warming, embryos were cultured in groups of up to 20 in 20 microl microdrops of modified KSOM or modified KSOM containing 100 micro M beta-mercaptoethanol at 38.5°C in 5% CO[2] in air. Survival after warming was assessed as the percentage of vitrified embryos that re-exp and ed and the percent that hatched after 48 hrs culture. Post-warming survival rates were not affected by type of carrier or age of the exp and ed blastocyst [P>0.05]. The proportions of embryos that re-exp and ed [55.5%] and hatched [25.7%] were higher [P<0.01] for those cultured with beta-mercaptoethanol than for those cultured without [re-expansion: 42.4%; hatching: 12.6%]. In conclusion, the microcapillary pipette tip represents an inexpensive alternative to the open pulled straw for cryopreservation

Pregnancy rates of frozen embryos recovered during winter and summer in Sistani cows

During spring, summer and winter seasons, Sistani donor cows, with normal reproductive status, were superovulated and embryos were recovered non-surgically on day 7. Grade A blastocyst embryos were either transferred fresh [spring] or frozen [summer and winter]. Recovered embryos during summer and winter were exposed to glycerol and frozen using conventional method. During spring season, recipient females [n = 70] were synchronized using two consecutive injections of prostaglandin F[2alpha] analogue, 14 days apart. On day 7 after the ensuing cycle, the females were assigned into three groups to receive single embryo, either fresh [n = 14; control; recovered embryos in spring] or frozen blastocyst recovered and frozen in summer [n = 27] or winter [n = 29]. Pregnancies were diagnosed by ultrasound examination, 30 days after non-surgical embryo transfer. Pregnancy rates following transfer of fresh embryos [64.3%] were higher than those that received frozen-thawed embryos [17.86%; P<0.05]. There was not any significant difference between pregnancy rates of recipients receiving embryos frozen in summer [18,5%] or winter [17.2%; P>0.05]

Changes in the plasma concentrations of thyroid hormones in ewes and the effect of intravenous injection of leptin on their levels

The aim of this study was to determine changes in the concentration of leptin and thyroid hormone in energyrestricted ewes and effect of leptin injection on thyroid hormone level. In the first experiment, 28 ewes were assigned to two groups [n = 14]. Ewes were fed by a ration that provided 60% or 100% of maintenance energy requirements during 71 days. Blood samples were collected and body weight [BW] and body condition score [BCS] were determined. In the second experiment, 6 energy-restricted ewes from the first experiment were selected and assigned to two groups [n = 3]. Ewes were fed a ration that provided 60% of maintenance energy requirements and injected by 1 or 4 micro leptin/Kg BW. Blood samples were taken and BW and BCS were determined. In the first experiment, concentrations of leptin, T[3] and T[4], BW and BCS were decreased in energyrestricted ewes [p < 0.01]. In the second experiment, concentration of T[3], T[4] and leptin were increased by leptin injection [p < 0.01]. The results suggested leptin injection may restore thyroid hormone secretion to normal levels in energy-restricted ewes

Effect of lactose extender with different levels of osmolality and pH on the viability of bactrian camel [camelus bactrianus] spermatozoa

The effect of different levels of osmolality and pH of lactose extender on the viability of Bactrian camel spermatozoa was investigated. Semen was collected from 10 Bactrian camel bulls using modified bovine artificial vagina. In experiment I, the extenders consisted of 9, 10, 11, 12 and 13% lactose with respective osmolalities of 290, 333, 350, 376 and 419 mOsm/kg and the pH of 6.9. In experiment II, 10% lactose extender with different levels of pH = 5.9, 6.9, 7.5, 7.9 and 8.9 were compared. All extenders contained 20% egg yolk and antibiotics. There were three replicates [ejaculates] for each trial. After dilution, semen was evaluated for progressive forward motility [PFM], plasma membrane integrity [PMI] and live percentage of sperm, at time 0, 4, 12 and 24 hrs after incubation at 4[degree]C. Viability of sperm was similar among 9-11% lactose concentrations at time 0 and 4. PFM was compromised [<8%] at 10 and 11% lactose extenders at time 12. Although, PFM was greatest at time 0 [P<0.05] for the pH of 6.9, it reduced to 15% at time 4 [P<0.05]. At the pH of 5.9-7.9, PMI and live percentage of sperm reduced at time 12 and 24, respectively [P<0.05]. In conclusion, 9-11% lactose with the pH of 6.9 may consider as a suitable extender for the shortterm preservation [up to 4 hrs] of Bactrian camel semen maintained at chilled condition [4[degree]C]

[Effect of reducing dose of GnRH analogue used in heat-synch program on pregnancy rate and day open of dairy cows]

To reduce the cost of hormones used in Heat-synch protocol in dairy cows. Enpenimental study.144 Holstein cows, at 50 days postpartum. Cows randomly assigned into 3 groups: [1] 40 cows; 7.5micro g luliberin, IM. [2] 45 cows; 15 micro g luliberin, IM. Seven days later in both groups, 150 micro g D-cloprostenol, IM 25 hours later Img Estradiol Benzoate was injected. Cows olserved for 48 hours and inseminated based on standing heat. Cows that did not display estrus were inseminated at 48 hours after estradiol injection. [3]Control: group in=59, did not received any treatment and were inseminated 12 hours after displaying estrus. Pregnancy was diagnosed on day 42 after AI via rectal palpation.Days open and pregnancy rate were analyzed by One-way ANOVA and chi square tests, respectively.The number of days open did not differ among experimental groups [group one: 104.17 +/- 7.76 days, group two: 106.28 +/- 6.24 days and the third group: 111.86 +/- 2.33 days [P>0.05]. Pregnancy rate to the first service was not different among groups [group one: 47.5%, 19/40, group two: 48.88%, 22/45, third group: 32.20%, 19/59][P>0.05]. In conclusion, reducing the dose of GnRH analogue [Luliberin] to half of the full dose did not affect pregnancy rate and days open. Therefore the cost of Heat-synch program can be reduced by using half dose of Luliberin