Anatomicohistological Characteristics of the Female Genital Organs of the White‐lipped Peccary (Tayassu pecari) in the Peruvian Amazon

This study examined the anatomical and histological characteristics of the genital organs of the female white‐lipped peccary in the wild in different reproductive stages, collected by rural hunters in the North‐eastern Peruvian Amazon. Mean ovulation rate was 2.12 ± 0.83 follicles and litter size was 1.78 ± 0.41 embryos or fetuses per pregnant female, resulting in a low rate of reproductive wastage, averaging 0.33 ± 0.66 (16.04%) oocytes or embryos per pregnancy. The ovulation rate and the anatomical performance of the uterus could limit the prolificacy of this species. Females in follicular phase showed follicular waves suggesting the synchronous growth of a cohort of follicles. Different uterine and vaginal epithelium features changed in accordance with the reproductive state of the female. Pregnant females and females in the luteal phase presented a significant proliferation of endometrial uterine glands, characterized by hyperplasia and branching of endometrial glands, and increase in the proportion of cervical epithelial cells with periodic acid‐schiff (PAS)‐positive granules compared with that in females in the follicular phase. Females in the follicular phase showed a more developed vaginal epithelium (in thickness and in layer composition) than females in the luteal phase and pregnant females.     

Ovine uterine morphogenesis: histochemical aspects of endometrial development in the fetus and neonate

Uterine tissues obtained from fetal (d 60 to term; n = 17; d 0 = day of mating) and neonatal (n = 9; d 0 = birth) lambs were subjected to alcian blue-8GX and fluorescein isothiocyanate (FITC)-lectin histochemistry to determine if alcianophilic properties of the epitheliomesenchymal interface (EMI) changed during endometrial morphogenesis and to characterize distribution of binding sites for seven FITC-lectins during uterine development. Neonatal lambs were subjected to bilateral ovariectomy and unilateral hysterectomy (BOHX; n = 3) or unilateral ovariohysterectomy (UOHX; n = 3) on d 0. Remaining tissues were recovered on d 14. Procedures allowed within-animal comparisons of endometrial responses and assessment of the role of the ovary in endometrial morphogenesis. Uteri also were obtained from three intact neonatal lambs by hysterectomy (d 14, d 15 and d 26). Alcianophilic properties of the EMI characteristic of polyanionic glycosaminoglycans (GAG) changed with onset of endometrial remodelling after fetal d 60 and were characterized by loss of EMI alcianophilia at or above .3 M MgCl2 and at low pH. Alcianophilic properties of the neonatal endometrium suggested restabilization of lumenal EMI and destabilization of the EMI in developing endometrial glands. Five of seven FITC-lectins bound to both fetal and neonatal uterine tissue. Tissues from UOHX, BOHX and intact ewes were indistinguishable histochemically. Data provide evidence of a role for GAG in ovine endometrial morphogenesis, ovary-independent initiation of endometrial glandular development, and illustrate potential uses of FITC-lectin conjugates in studies of ungulate uterine tissues.     

Histological Changes of the Feline Cervix, Endometrium and Placenta after Mid-gestational Termination of Pregnancy with Aglepristone

This study was conducted to investigate endometrial and placental structural changes that occurred in response to mid‐gestational termination of pregnancy in queens using aglepristone, a progesterone receptor antagonist. Thirteen European Shorthair pregnant queens were either treated with aglepristone (10 mg/kg body weight; subcutaneously) twice on days 25 and 26 after first mating (am; group I; n = 9), or remained untreated and served as control (group II; n = 4). Queens of group I were ovariohysterectomized between days 30 and 41 am, either at the onset (n = 3) or during (n = 1) abortion and 12 h (n = 1), 24 h (n = 3) or 10 days after abortion (n = 1). Queens of group II were ovariohysterectomized on day 30 am. Tissue was collected from the cervix, and the interplacental zone as well as the paraplacenta/placental girdle of the uterus, subjected to standard histological procedures and evaluated using light microscopy. During abortion, gaps appeared within the paraplacenta and the placental girdle which were filled with blood, leading to an embryo‐maternal disconnection. Blood was also observed within the uterine lumen as well as the interstitial mucosal stroma of the cervix and the placental girdle zone and probably originated from damaged venules, whilst arterioles remained intact. As the interval between abortion and surgery increased, the interstitial and luminal haemorrhages became less pronounced and completely disappeared except interstitial remnants 10 days after abortion. The endometrial regeneration was not fully completed on day 10 after abortion and a few cystically dilated glands were evident. In conclusion, abortion of queens through aglepristone given during mid‐gestation is assumed to be the result of damage of uterine venules. This leads to an interstitial haemorrhages and bleeding into the uterine lumen, subsequently resulting in utero‐placental detachment.     

X-ray Microanalysis of the Secretory Epithelium of the Endometrial Glands and Intraluminal Uterine Fluid in Oestrus Mares

X‐ray microanalysis was used to determine the occurrence of transudation as a source of intrauterine fluid in mares during oestrus. The content of some selected elements was studied in secretory vesicles of the epithelium of endometrial glands and in intraluminal fluid of healthy mares of varying age and parity. An in situ cotton tampon was used to absorb intrauterine fluid from 23 gynaecologically healthy mares during oestrus. Immediately after tampon withdrawal, endometrial tissue for biopsy was removed from the uterine body/horn junction while videoendoscopy was performed. The tissue specimens were frozen ultra‐rapidly against a copper surface chilled with liquid N₂. X‐ray microanalysis of frozen fully hydrated endometrial samples and of microdroplets of intraluminal fluid (n = 20) was performed, using a SEM microscope equipped with a cryo‐stage and an X‐ray microanalysis system. The concentrations of sodium (Na), potassium (K), chlorine (Cl), sulphur (S), phosphorus (P) and calcium (Ca) in the epithelium of endometrial glands and in intraluminal fluid were compared with those in serum. There was a significant difference in the concentrations of all analysed elements between the secretory gland epithelium and the intraluminal fluid apart from S. The major elements in glandular epithelium were K and P. Although there was a significant difference in the concentrations of Na, Cl, S and Ca between the uterine fluid and serum, there was still a conspicuous resemblance in the relationship between the different elements in uterine fluid and serum, with Na and Cl being the dominant elements. Sulphur and especially Ca were present only in small amounts throughout. Neither age nor parity affected the elemental concentrations of Na, K, Cl, S, P and Ca in gland epithelium, uterine fluid or serum. It was concluded that serum transudation contributes to a great extent to the composition of uterine fluid, having a diluting effect upon the specific secretion of the uterine glands.     

Anatomicohistological characteristics of the tubular genital organs of the female collared peccary (Tayassu tajacu) from North-eastern Amazon

The present study examines anatomical and histological characteristics of tubular genital organs and its relationships with the reproductive state of 24 wild adult collared peccary (Tayassu tajacu) females. The tunica mucosa of the uterine tube presents a pseudostratified, intermittently ciliated columnar epithelium. The epithelial secretory cells of pregnant females and females in the luteal phase of the oestrous cycle became taller than the ciliated cells and showed abundant apical secretory blebs, whereas secretory cells of females in the follicular phase showed abundant mucous secretory activity (periodic acid-Schiff positive cells). The uterus is composed of two narrow and convoluted uterine horns, separated by the velum uteri, a small uterine body and a long and muscular cervix. The endometrial lining of both uterine horns and body is a monostratified, columnar ciliated epithelium. Pregnant females and females in luteal phase showed a more developed hyperplasia of the endometrial simple tubular glands than females in the follicular phase. The cervix presents interdigitated rows of mucosal prominences that project into the lumen, structures similar to pulvini cervicali, occluding the cervical canal. In pregnant females, the endocervical canal was filled by a viscous cervical secretion. Females in follicular phase presented a thicker vaginal epithelium than pregnant females and females in luteal phase. The present study suggests that the collared peccary female showed different histological features of the uterine tubes, uterus and vagina in accordance with the reproductive state of the females.     

Retinol and estradiol regulation of retinol binding protein and prostaglandin production by porcine uterine epithelial cells in vitro

Secretion into the uterine lumen follows a precise pattern during early pregnancy. Near the end of the second week of pregnancy and coincident with elongation of conceptuses, retinol, retinol binding protein (RBP), estradiol (E2), and prostaglandins E (PGE) and F (PGF) increase in the uterine lumen, and RBP mRNA increases in the endometrium. In the present studies the potential for E2 (0.1 microM) and retinol (10 microM) to regulate RBP and PG production by cultured luminal (LEC) and glandular (GEC) epithelial cells collected from postpubertal females and LEC from prepubertal gilts was examined. Endometrial tissue was collected surgically from cyclic and pregnant females (n = 8) on d 10 and 13 postestrus (first day of estrus = d 0) and from 120- and 150-d-old prepubertal gilts that were treated with progesterone (P4) (2.2 mg x kg(-1) x d(-1), n = 6) or corn oil (n = 6) for 14 d prior to tissue collection. The LEC from postpubertal females responded to retinol with increased (P < 0.05) RBP, PGE, and PGF in culture medium and increased (P < 0.07) RBP mRNA but E2 decreased (P < 0.05) RBP and RBP mRNA and had no effect on prostaglandins. No E2 or retinol effects on secretions of GEC occurred in vitro, but a day x pregnancy status interaction (P < 0.06) affected PGE output by the GEC. Secretion of PGE was greater when GEC were collected on d 10 of pregnancy than from d-10 cyclic or d-13 pregnant or cyclic females. Both E2 and retinol stimulated (P < 0.05) secretion of RBP by LEC isolated from prepubertal gilts, but their effects were not additive. In vivo treatment of prepubertal gilts with P4 increased (P < 0.05) RBP and decreased (P < 0.05) PG production by LEC in vitro. Therefore responses to E2 and retinol differ between pre- and post-pubertal females, and retinol may function in the regulation of endometrial RBP and PG secretion.     

Matrix Metalloproteinase (MMP)-2 and MMP-9 Activity in the Canine Uterus Before and During Placentation

The aim of the present study was to demonstrate the presence and localization of MMP-2 and -9 by means of RT-PCR and immunohistochemistry (IHC) within the canine uterus from the pre-implantation stage until mid-gestation and to determine MMP-2 and -9 activities by means of zymography. For this purpose, samples of the uterus and salpinx from bitches were obtained after ovariohysterectomy. Pre-implantation stages (5-12 days after mating, n = 11) were determined by verifying embryos after flushing the uterus. Further groups were determined as implantation (15-19 days after mating, n = 9), post-implantation (20-30 days after mating, n = 9) and placental stages (30-45 days after mating, n = 3). A non-pregnant group (17-30 days after mating, n = 4) served as control. MMP-2 and -9 positive cells were detected in all specimens from pregnant and nonpregnant bitches, however, with different distributions. MMP-2 was present in endothelium and smooth muscles of blood vessels and the myometrium of pregnant and nonpregnant bitches, additionally in the surface epithelium of the oviduct. The latter also stained positive for MMP-9. During placentation, MMP-2 was detected mainly in fetal blood vessels and trophoblastic cells. Higher MMP-2 activity was observed in the endometrium and myometrium of all pregnant groups compared with the nonpregnant group (p < 0.05). The pregnant groups did not differ significantly from each other (p > 0.05). MMP-9 was present in blood vessels, smooth muscle cells and epithelia, such as maternal surface epithelial cells, uterine crypts and glands. During placentation, the deep uterine glands and the epithelium of the glandular chambers were immunoreactive to MMP-9. Highest MMP-9 activities were reached in the endometrium of the pre-implantation group (23.2% of total MMP-9) and placental parts (33.3%).     

Increased incidence of DNA amplification in follicular than in uterine and blood samples indicates possible tropism of Neospora caninum to the ovarian follicle

This study evaluated the presence of Neospora caninum in ovarian follicle aspirates and uterine flushes obtained from N. caninum seropositive dairy cows. Ninety-two cows that aborted within the previous 90 days were sampled to determine the presence of antibodies against N. caninum. Thirteen seropositive cows were chosen for collection of blood leukocytes, uterine flushes (UF; n=12) and follicular aspirates (OPU; n=13). Samples were centrifuged and the cellular sediment from the follicular fluid, uterine flushes and blood leukocytes were used for DNA extraction and PCR. Follicular aspirates had the highest frequency of DNA amplification for N. caninum (p<0.05, 92.3%; 12/13). Whereas uterine (4/12) and blood leukocyte (5/13) samples had similar (p>0.05) rate of positive results. Nonetheless, there was no agreement between blood leukocytes and follicular samples taken from the same animal (Cohen Kappa=-0.16). Similarly, blood leukocytes and uterine results had moderate agreement between them (Cohen Kappa=0.47). This study indicates that N. caninum is present in the ovarian follicle and uterus of seropositive cows, suggesting a possible risk of neosporosis transmission between females during oocyte and embryo collection and transfer. Hence, precautions should be taken to minimize the risk of N. caninum transmission. Furthermore, the high incidence of positive results in follicle samples, that exceeded that of their paired blood leukocytes, suggests a possible tropism of N. caninum for the ovarian follicle.     

Use of a Mycobacterial Cell Wall Extract (MCWE) in Susceptible Mares to Clear Experimentally Induced Endometritis With Streptococcus zooepidemicus

The ability of an immunomodulator, mycobacterial cell wall extract (MCWE), to clear uterine infection in susceptible mares after an experimental challenge withStreptococcus zooepidemicus was evaluated. Thirty mares susceptible to endometritis, based on the presence of uterine fluid during both diestrus and estrus, were selected from a herd of 896 and inoculated with a live culture of 5 × 10⁶ CFU of S. zooepidemicus on day 1 of estrus. Twenty-four hours later, mares were evaluated by ultrasonography, bacteriology, exfoliative cytology, and uterine biopsy to confirm infection. Forty-eight hours after inoculation, and on confirmation of uterine infection, mares were randomly assigned to one of four unbalanced experimental treatments to receive 1500 μg MCWE IU (n = 10) or IV (n = 10), or placebo IU (n = 5) or IV (n = 5). Mares were examined at ovulation and 7 days post-ovulation for uterine fluid via transrectal ultrasonography and for bacteriology, exfoliative cytology, and uterine biopsy. Efficacy was based on the ability of the mare to clear endometritis as determined by negative bacteriology and reduced numbers of polymorphonuclear cells (PMNs) on uterine biopsy. Because no statistical difference was detected between routes of administration on day 7 post-ovulation, the data sets were combined and re-analyzed to evaluate overall efficacy. Endometritis was observed in all placebo-treated mares 7 days post-ovulation, whereas treatment with MCWE resulted in the elimination of endometritis in 35% of the mares by the time of ovulation, and 70% of the mares by 7 days post-ovulation. Treatment with MCWE, compared with the placebo group, resulted in a significant decrease in the number of mares positive for endometritis at ovulation based on exfoliative cytology and bacteriology (P < .01) and at 7 days post-ovulation based on biopsy, exfoliative cytology, and bacteriology (P < .001). Results indicate that MCWE was an effective treatment for the elimination of endometritis caused by S. zooepidemicus in mares.     

The use of clenbuterol for the management of large animal dystocias: surgical corrections in the cow and ewe

Clenbuterol (Ventipulmin® Solution) was included in the corrective management of dystocia cases requiring obstetrical surgery encountered in a Quebec rural practice. Data were collected on a total of 69 cases: 63 bovine and three ovine caesareans, and three bovine fetotomies. Ease of exteriorization of the gravid uterus and postoperative development of uterine adhesions were compared in two groups of bovine caesarean cases: a clenbuterol-treated group (Group A, n = 63) and a nontreated control group (Group B, n = 90). Clenbuterol produced a potent myometrial relaxant effect making its use beneficial in the correction of the bovine and ovine dystocias. It provided significantly improved uterine maneuverability (ײ = 47.63, P < 0.001) and significantly reduced postoperative development of adhesions (ײ = 14.05, P < 0.001) except in bovine caesarean cases with a high degree of myometrial distension. Neonatal and maternal health were not impaired and retention of fetal membranes was not increased. When used as directed, clenbuterol was a safe, reliable, and efficacious drug.     

Isolation technique for lymphocytes from bovine lymph glands

A method is described for obtaining large quantities (grams) of lymphocytes from bovine retropharyngial lymph glands, whereby contaminating erythrocytes are lysed and coagulation is prevented by the use of acetic acid (0.0143 mol 1^–1). On average 4.38 g (S. D. 1.83, n=100) lymphocytes, including lymphoblasts, are obtained per lymph gland, with a purity level of about 99%.     

The importance of seminal plasma on the fertility of subsequent artificial inseminations in swine

Yorkshire x Landrace sows and gilts were used in a 3x2 factorial arrangement of treatments to determine the effect of uterine inflammation induced by either killed spermatozoa (KS) or bacterial lipopolysaccharide (LPS) on the fertility of a subsequent, optimally timed AI. Estrus was detected with a mature boar twice daily. Twelve hours after the first detection of estrus, females received intrauterine infusions of an inflammatory stimulus consisting of a 100-mL dose of extender containing 3x10(9) KS (n = 40), 20 microg of LPS (n = 40; positive control) or extender alone (n = 40; negative control). An insemination was performed 12 to 18 h later with 3x10(9) motile spermatozoa (i.e., fertile AI) suspended in either 100 mL of seminal plasma (SP; n = 60) or extender replenished with of estrogens (5 microg of estradiol-17beta, 4.5 microg of estrone sulfate, and 2 microg of estrone; n= 60). Transcutaneous ultrasound was performed at the time of fertile AI and again 24 h later to detect the presence or absence of preovulatory follicles. A fertile AI performed within 24 h before ovulation was considered optimal. Conception (CR) and farrowing rates (FR) were greater in females that received a fertile AI diluted with SP compared with extender (P<.01), and there was a significant (P<.05) treatment x fertile AI dilution medium interaction for both CR and FR. Females that received a fertile AI 12 h after infusion of extender had similar CR and FR regardless of fertile AI dilution medium. After inducing an inflammatory response with either KS or LPS, CR and FR were higher in females that received a fertile AI diluted with SP compared with fertile AI dilution with extender (P<.05). The effects of treatment and AI dilution media and their interactions were not significant for litter size in females that farrowed. These results show that the fertility of a subsequent AI can be impaired when semen is deposited into an inflamed environment created by an earlier AI, and this impairment was offset by inclusion of SP in the subsequent insemination.     

Expression of Progesterone Receptor in the Utero‐tubal Junction After Intra‐uterine and Deep Intra‐uterine Insemination in Sows

The aim of this study was to investigate the expression of progesterone receptor (PR) in the utero‐tubal junction (UTJ) of sows at 24 h after intra‐uterine insemination (IUI) and deep intra‐uterine insemination (DIUI) compared with conventional artificial insemination (AI) in pigs. Fifteen multiparous sows were used: AI (n = 5), IUI (n = 5) and DIUI (n = 5). The sows were inseminated with a single dose of diluted semen during the second oestrus after weaning at 6–8 h prior to ovulation (AI: 3000 × 10⁶ spermatozoa, IUI: 1000 × 10⁶ spermatozoa and DIUI: 150 × 10⁶ spermatozoa). The UTJ was collected and subject to immunohistochemical staining using avidin‐biotin immunoperoxidase technique with mouse monoclonal antibody to PR. In the oviductal part of the UTJ, the intensity of PR in the tunica muscularis and the proportion of PR‐positive cells in the surface epithelium after DIUI were lower than AI (p < 0.05). The intensity and the proportion of PR‐positive cells between AI and IUI in all compartments of the UTJ did not differ significantly (p > 0.05). When comparing between tissue compartments, prominent staining was observed in the muscular layer of the UTJ. It could be concluded that the expression of PR in the UTJ prior to fertilization after DIUI with a reduced number of spermatozoa was lower than that after AI. This might influence sperm transportation and the fertilization process.     

Ultrasonic assessment of puerperal uterine involution in Balady goats

Twenty-six postpartum Balady goats (primiparous, n=13; pluriparous, n=13) were used in this study. One animal of each group was slaughtered on postpartum days 1, 2, 4, 7, 10, 13, 19 and 25; in addition, three control nulliparous goats were slaughtered, and the genital tracts collected. Progress of uterine involution was monitored by repeated ultrasonographic measurements in live animals (primiparous n=6; pluriparous n=6) and measurement of the outer circumference of the uterine horns of slaughtered animals (primiparous n=8; pluriparous n=8). A consistent and progressive decrease in ultrasonographic and outer circumference measurements was found, although faster during the first 7 days postpartum than between days 7 and 19 postpartum. Uterine involution, assessed by the upper limit of the measurements in the nulliparous goats, followed a quadratic pattern and was completed by day 19 postpartum. Ultrasonographically, two elliptical-circular echogenic areas separated by an anechoic line of the stratum vascularis were depicted. Regressing caruncles and fluid in uterine lumen were recognized during the first week postpartum. Further analysis revealed a highly positive correlation between the outer circumference and ultrasonographic measurements. In conclusion, uterine involution in Balady goats was completed by day 19 postpartum and was unrelated to parity. The close association between ultrasound findings and macroscopic involution indicated that ultrasonography can dependably be used to monitor uterine involution under field conditions and can be a suitable alternative to animal slaughter for the study of uterine involution.     

The effect of spermatozoa and seminal plasma on leukocyte migration into the uterus of gilts.

Yorkshire x Landrace gilts were used to determine the effect of spermatozoa and seminal plasma on postbreeding uterine leukocyte influx. Estrus detection was performed with a boar at 12-h intervals following synchronization with 400 IU eCG and 200 IU of hCG. All gilts were AI once, 24 h after the detection of estrus following random assignment to a 2x2x3 factorial arrangement of treatments (sperm or sperm-free AI doses), AI dose medium (seminal plasma or PBS), and lavage time following AI. Gilts were treated with sperm (5x10(9) spermatozoa; SPZ; n = 30) or sperm-free (SF; n = 30) doses containing either 100 mL of seminal plasma (SP; n = 15/treatment) or PBS (n = 15/treatment). Uterine lavage was performed once on each gilt (n = 20/time) at one of three times after AI (6, 12, or 36 h) to determine the total number of uterine leukocytes. The leukocytes consisted predominately (92 to 99%) of polymorphonuclear neutrophilic granulocytes (PMN). There was an AI x medium interaction on uterine PMN numbers. The number of uterine PMN recovered from gilts inseminated with sperm suspended in PBS was greater than the number of PMN recovered from the uterine lumen of gilts inseminated with sperm in SP, SP alone, or PBS alone (P<.05). Furthermore, SP accelerated the rate of uterine clearance when suspended with sperm cells during the first 36 h following AI (P<.05). These results indicate that seminal plasma suppresses PMN migration into the uterus following breeding and enhances the rate of disappearance of uterine inflammation.     

Changes of Connexin43 Expression in Non‐pregnant Porcine Myometrium Correlate with Progesterone Concentration During Oestrous Cycle

Connexin43 (Cx43) is a major protein of myometrial gap junctions. The number of Cx43 gap junctions increase dramatically with the onset of labour in association with development of synchronized uterine contractions. The formation of myometrial gap junctions follows an increase in the oestrogen to progesterone ratio indicating an important role of steroid hormones in regulating Cx43 expression at term. However, no relationship has been established between the expression of Cx43 in the non‐pregnant myometrium and concentration of steroid hormones during the oestrous cycle. Here, we used immunofluorescence and Western blotting to analyse the expression of Cx43 gap junctions in the myometrium of pre‐pubertal pigs (n = 7) and mature pigs at pre‐ovulatory (n = 7), luteal (n = 5) and late luteal (n = 3) stages of the oestrous cycle. The number of Cx43 gap junctions calculated per 1 mm² of the myometrial section was low in pre‐pubertal pigs and significantly higher (p < 0.022) in pre‐ovulatory animals. In relation to pre‐ovulatory animals the number of myometrial gap junctions was significantly lower (p < 0.019) at the luteal phase and correlated with significantly higher (p < 0.005) concentration of endogenous progesterone. Phosphorylated isoforms of Cx43 protein were expressed in the myometrium of pre‐pubertal pigs and mature animals at pre‐ovulatory and late luteal phases, while they were down regulated at the luteal stage. These results indicate that changes of Cx43 expression in the porcine myometrium during the oestrous cycle may be regulated by progesterone concentration and may contribute to the modulation of uterine motility.     

Estrogenic effects of genistein on reproductive tissues of ovariectomized gilts

The soybean phytoestrogen genistein has a range of estrogenic actions demonstrated in various species; however, only limited research has been done to investigate its effects in swine. The objective of this study was to characterize the effects of a graded dose of genistein on estrogen-sensitive uterine and cervical tissues in ovariectomized gilts. Thirty-four postpubertal gilts were ovariectomized and assigned randomly to 1 of 6 treatment groups 15 d postovariectomy. Treatment groups received vehicle, estradiol benzoate (2 mg/d), or genistein (50, 100, 200, or 400 mg/d) via intramuscular injection at 12-h intervals for 10 d. Following the treatment period, gilts were euthanized, and uterine and cervical tissues were collected and processed for chemical or histological analysis. Uterine and cervical tissue mass, as indicated by wet, dry, and protein weights and total DNA content (expressed per 100 kg of BW), increased as the dosage of genistein increased (P < 0.001 for each regression). Uterine and cervical wet weights were increased by a dosage of 200 mg of genistein/d (P < 0.001 and P < 0.01, respectively) but not by 100 mg of genistein/d (P = 0.38 and P = 0.14, respectively) compared with those of control gilts. Height of epithelial cells lining the uterine glands and the lumen of uterus and cervix increased when gilts were treated with estradiol benzoate or 400 mg of genistein/d (P < 0.01). When the gilts were treated with estradiol benzoate or 400 mg of genistein/d, immunohistochemical staining demonstrated an increase in the percentage of cells that stained positive for progesterone receptor in the uterine glands and in the cells lining the vaginal cervix (P < 0.05). In gilts treated with 400 mg of genistein/d, the percentage of cells stained positive for proliferating cell nuclear antigen increased in the epithelium of the uterine glands, uterine lumen, and vaginal cervix (P < 0.05). Tissue growth was stimulated by genistein in a dosage-dependent manner, although no dosage of genistein induced a response as great as that of estradiol benzoate. Estrogen-sensitive tissues of the ovariectomized gilt, such as the cervix and uterus, are affected by injection of large dosages of the phytoestrogen genistein. The sensitivity of the uterus of the gilt to estrogenic substances makes it a potential model to examine the impact of environmental endocrine modulators on reproductive tissues.     

The effect of metritis and subclinical hypocalcemia on uterine involution in dairy cows evaluated by sonomicrometry

The objective of this study was to examine the effects of metritis and subclinical hypocalcemia on reduction of uterine size in dairy cows using ultrasonography and sonomicrometry. Four piezoelectric crystals were implanted via laparotomy into the myometrium of the pregnant uterine horn of 12 pluriparous Holstein Friesian cows 3 weeks before the calculated calving date. Sonometric measurements were conducted daily from 2 days before parturition (= Day 0) until Day 14 after calving and then every other day until Day 28. Distances between adjacent crystals were expressed in relation to reference values obtained before calving. The diameter of the formerly pregnant uterine horn was measured using transrectal B-Mode sonography starting on Day 10. Cows were retrospectively divided into the following groups: cows without metritis (M–; n = 7), cows with metritis (M+; n = 5), cows with normocalcemia (SH–; Ca > 2.0 mmol/l on Days 1 to 3; n = 5) and cows with subclinical hypocalcemia (SH+; Ca < 2.0 mmol/l in at least one sample between Days 1 and 3; n = 7). Metritis did not affect (P > 0.05) sonometric measurements, but the diameter of the formerly pregnant horn was larger (P ≤ 0.05) between Days 15 and 21 in M+ cows than in M‒ cows. Reduction in uterine length in hypocalcemic cows was delayed (P ≤ 0.05) between Days 8 and 21 compared with normocalcemic cows, but the uterine horn diameter was not related to calcium status. In conclusion, both diseases affected reduction of uterine size until Day 28. Cows with metritis had a larger uterine diameter, possibly attributable to accumulation of lochia, and cows with subclinical hypocalcemia had delayed reduction of uterine length, presumably related to reduction of myometrial contractility.     

HIGH-RESOLUTION PARATHYROID SONOGRAPHY

The purpose of this study was to assess the diagnostic utility of parathyroid ultrasonography to differentiate causes of hypercalcemia in dogs. We analyzed qualitative and quantitative ultrasound imaging findings and clinical pathology data from 33 dogs that underwent parathyroid ultrasound examination as part of the diagnostic evaluation for hypercalcemia. Diagnoses of the diseases causing hypercalcemia included parathyroid carcinoma (n = S), parathyroid adenoma (n = 15), parathyroid adenomatous hyperplasia (n = 6), chronic renal insufficiency (n = 3), and hypercalcemia of malignancy (n = 4). All parathyroid lesions were round or oval and hypoechoic compared with surrounding thyroid parenchyma. Adenomatous and adenocarcinomatous glands were 4 mm or larger in longest linear measurement on US examination and were statistically significantly larger than hyperplastic glands. (p < 0.001) Linear measurements of parathyroid glands acquired at the time of ultrasound examination correlated well with direct siz determination after surgical excision. (r²= 0.9, p < 0.0001) Parathyroid lesions <4 mm are highly suspicious for parathyroid adenoma or carcinoma, while US lesions <4 mm most likely represent primary adenomatous hyperplasia or secondary parathyroid hyperplasia. Parathyroid size estimation from ultrasound examination is an accurate predictor of true size.