Gene Expression of Fresh and Frozen/Thawed Canine Embryos.

BACKGROUND: Canine embryo cryopreservation and subsequent transfer are relevant in the use of reproductive technologies. OBJECTIVE: The purpose of this study is the identification and quantification of the gene expression BAX and Bcl2, AQP3, Na+/K+ ATPase alpha-1 and beta-1 and LIFr in canine embryos obtained in vivo and after freezing. MATERIALS AND METHODS: For the collection of embryos, the bitches were identified at pro-estrous until the detection of 80-90% superficial cells. After that, they were artificially inseminated with fresh semen. The embryos were collected after ovariohysterectomy. RNA was extracted and amplified, and embryos were randomly distributed into fresh (Fr) and frozen/thawed (Ft) groups. RESULTS: Eighteen blastocysts were collected from three bitches. Genes BAX, AQP3 and LIFr did not differ among the studied groups. CONCLUSION: We suggest, through these results, that the genes BAX, Bcl2, AQP3, Na + / K + ATPase alpha-1 and beta-1 and LIFr were expressed in canine blastocysts collected in vivo and after slow freezing cryopreservation.

Is the right testis more affected by cryptorchidism than the left testis? An ultrasonographic approach in dogs of different sizes and breeds.

BACKGROUND: Considered the most common congenital testicular abnormality of companion animals and a predisposition factor to the development of testicular neoplasia, cryptorchidism is defined as the non-descent of one or both testes to their normal anatomical location. Data on the occurrence of cryptorchidism in Brazil are scarce. The purpose of this work was to verify the occurrence of cryptorchidism in dogs of different sizes and breeds. MATERIALS AND METHODS: Cryptorchidism identification was carried out by ultrasound scanning, from November, 1994 to March, 2007, at the Centre for Veterinarian Diagnosis and Support (Centro de Apoio e Diagnóstico Veterinário - CAD), in Rio de Janeiro. 4924 male dogs of different breeds were examined, revealing 403 (8.2%) cryptorchidism. RESULTS: In this study, occurrence took place more often on the right testicle (59.5%), more frequently displaying inguinal localisation (59.5%) and unilateral occurrence (70%). Regarding bilateral presentation, the symmetrical form was the most common (86.8%). Cryptorchidism was more common in the inguinal region of dog of small sized breeds and in the abdominal region in dogs of medium- and large-sized breeds. CONCLUSIONS: Ultrasound scan proved a valuable diagnosis tool for cryptorchid testes, giving precise localisation and parenchymal changes thus leading to a safe clinical treatment.

Evaluation of follicular growth and tissue viability in vitrified/warmed domestic dog ovaries after in vitro culture.

Cryopreservation of gametes is an important tool to preserve fertility, but for most species, including domestic dogs, data regarding ovarian tissue cryopreservation are limited. We aimed to evaluate the follicular and tissue viability and follicular growth after in vitro culture of domestic dog ovarian cortical slices cryopreserved by vitrification. Ovarian cortex was obtained from ten pairs of ovaries from domestic dogs using two methods (A and B), one for each ovary from the same bitch. At least four slices for each method were obtained from each ovary, one was processed for histology and the other three were vitrified. When the vitrified slices were warmed, one slice from each method was processed for histology and the remaining two slices were cultured in vitro for 7 days, after which they were processed for histological evaluation. Density of follicles in fresh samples was similar for both methods. For Method A, density of secondary follicles decreased, while the density of primordial follicles was maintained throughout the process. For Method B, density of primary follicles decreased after 7 days of incubation, but density of secondary follicles increased, confirming follicular growth in Method B. Overall, there were no differences between Methods A and B in follicular integrity after incubation. Fresh samples showed better arterial, venous and follicle preservation, followed by vitrified-warmed samples, but no differences were observed between methods. In conclusion, the methodology used to isolate the ovarian cortex may affect tissue and follicle viability as well as follicular development during in vitro culture.

Congelamento de sêmen e sua eficiência na inseminação artificial de cães / Semen freezing and its efficiency in the artificial insemination in dog

A fisiologia reprodutiva da espécie canina e a resposta insatisfatória do sêmen do cão à técnica da congelação são os dois maiores empecilhos aos esforços para o avanço da inseminação artificial em cães. Inúmeras pesquisas estão sendo desenvolvidas nessa área, gerando muitas informações, sobretudo na tecnologia de sêmen. O objetivo desse texto é discutir os principais avanços na avaliação e congelação de sêmen e sua influencia nos resultados de inseminação artificial.

The canine reproductive physiology and unsatisfactory results on techniques of frozen dog semen has been the biggest barrier on the improvement of artificial insemination in dogs. Many researches are been done in this area generating a lot of information, especially on semen technology. The aim of this text is to discuss the major advances on semen evaluation and semen frozen and its influence on artificial insemination results.

Congelamento de sêmen e sua eficiência na inseminação artificial de cães / Semen freezing and its efficiency in the artificial insemination in dog

A fisiologia reprodutiva da espécie canina e a resposta insatisfatória do sêmen do cão à técnica da congelação são os dois maiores empecilhos aos esforços para o avanço da inseminação artificial em cães. Inúmeras pesquisas estão sendo desenvolvidas nessa área, gerando muitas informações, sobretudo na tecnologia de sêmen. O objetivo desse texto é discutir os principais avanços na avaliação e congelação de sêmen e sua influencia nos resultados de inseminação artificial.(AU)

The canine reproductive physiology and unsatisfactory results on techniques of frozen dog semen has been the biggest barrier on the improvement of artificial insemination in dogs. Many researches are been done in this area generating a lot of information, especially on semen technology. The aim of this text is to discuss the major advances on semen evaluation and semen frozen and its influence on artificial insemination results. (AU)

Concentração de lactato e glicemia em cadelas e neonatos nascidos de cesariana / Lactato concentration in bitch and canine neonates born through cesarean section

Avaliaram-se a concentração de lactato e a glicemia em sete cadelas em trabalho de parto submetidas à cesariana e em seus respectivos neonatos. O lactato materno foi mensurado utilizando-se medidor portátil e pelo método enzimático colorimétrico. Nos neonatos avaliou-se também o peso ao nascimento. Os valores de lactato materno e neonatal foram estatisticamente diferentes, sendo mais elevado nos neonatos. Ao nascimento, as cadelas e os neonatos encontravam-se normoglicêmicos, e não se observou correlação entre a glicemia de ambos. Os valores de lactato obtidos pelo o analisador portátil (3,5±0,6mmol/L) foram mais altos do que os obtidos pelo método enzimático colorimétrico (1,6±0,6mmol/L). Observou-se correlação significativa entre o peso do neonato e a concentração de lactato, isto é, os filhotes de menor peso apresentaram maior concentração de lactato.

This work evaluated the concentration of lactate and blood glucose in seven bitches in labor subject to caesarean section and in their newborns. The lactate concentration was measured using a portable analyzer and enzymatic colorimetric method. In neonates, the birth weight was evaluated. The maternal and neonatal lactate values were statistically different, being higher in newborns. At birth, the bitches and the newborns had normal glucose status, and no correlation was observed between blood glucose in either. The lactate concentration obtained by the portable analyzer (3.5±0.6mmol/L) was higher than that obtained with the enzymatic colorimetric method (1.6±0.6mmol/L). There was significant correlation between the neonate weight and lactate concentration and in puppies with lighter weight there was a higher concentration of lactate.

Expressão gênica dos REα, REβ e PR em tumores mamários de cadelas por meio do q-PCR / REα, REβ and PR gene expression in mammary gland tumors of female dogs by q-PCR

A expressão de receptores de estrógeno (ER) e progesterona (PR) por meio da técnica de q-PCR foi avaliada em 26 cadelas portadoras de neoplasias mamárias e cinco cadelas sem afecções mamárias (grupo controle). Os resultados mostraram que os três grupos de animais estudados - com tumor maligno ou benigno e controle - expressaram receptores de estrógeno alfa, beta e progesterona. A quantificação relativa mostrou tendência para uma expressão maior de receptores no grupo controle e menor no grupo de animais com neoplasias malignas. Além disso, observou-se expressão maior de ERα em relação ao ERβ, e as neoplasias malignas de origem mista apresentaram maiores concentrações dos receptores PR, ERα e ERβ que as neoplasias de origem epitelial.

The estrogen and progesterone receptor (ER and PR) expression with the q-PCR technique was evaluated in 26 female dog carrying of mammary tumors and five female dogs without mammary disease (control group). The results showed that the three animal groups evaluated - malignant or benign tumor and control - expressed alpha and beta estrogen and progesterone receptors. The relative quantification showed a tendency for a higher expression of receptors from the control group and smaller in the malignat tumors animal group. Also, there was a major ERα expression regarding to ERβ and the malignat tumors from mixed origin presented higher concentrations of receptors PR, ERα and ERβ, when compared to tumors of epithelial origin.

Imunoistoquímica de útero e cérvice de cadelas com diagnóstico de piometra / Immunohistochemical of the cervix and uterus of bitches diagnosed with pyometra

Analisou-se a piometra de 31 cadelas, de raças e idades variadas, sendo 25 cadelas com piometra de cérvice aberta e seis de cérvice fechada. Após ovariossalpingo-histerectomia, foram coletados fragmentos da cérvice e do útero para a avaliação imunoistoquímica. Foram analisados os receptores de estrógenos α e β, progesterona e colágenos I e III. Foram realizadas imunomarcações em diferentes regiões da cérvice, como o epitélio glandular, o epitélio luminal e o estroma glandular, assim como em diferentes regiões do útero, como o epitélio glandular e o estroma glandular. As imunomarcações de colágenos I e III foram realizadas nas regiões glandular e muscular da cérvice e do útero. Concentrações de receptores de progesterona foram maiores em cadelas com piometra fechada.

The pyometra in 31 bitches of different breeds and ages, 25 with pyometra cervix open and 6 closed cervix was analyzed. After the ovariohysterectomy procedure, samples were collected from the cervix and uterus to evaluate immunohistochemistry. For immunohistochemical evaluation estrogen receptors α and β, progesterone and collagen I and III were analyzed. Immunostainings were performed in different regions of the cervix such as glandular epithelium, luminal epithelium and glandular stroma, as well as in different regions of the uterus, such as glandular epithelium and glandular stroma. The immunostainings for collagen I and III were performed in muscular and glandular regions of the cervix and uterus. The concentration the progesterone receptors were elevated in bitches from the closed pyometra.

Ovarian activity reversibility after the use of deslorelin acetate as a short-term contraceptive in domestic queens.

The objective was to evaluate ovarian activity reversibility in domestic queens after short-term contraceptive treatment with deslorelin acetate. Ten mature queens were used. In all queens, the estrous cycle was evaluated every 72 h by vaginal cytology (VC) and behavior assessments. When queens had VC characteristic of interestrus or diestrus, one deslorelin acetate implant (4.7 mg) was placed in the subcutaneous tissue of the interscapular region (day of insertion = Day 0). Thereafter, VC was performed every 48 h and on Day 90, implants were removed. At Day 100, estrus and ovulation were induced with 100 IU eCG (im), followed by 100 IU hCG (im), 84 h later (Day 103.5). Queens were ovariohysterectomized on Day 106. Corpora lutea (CL) were counted, oviducts were flushed, and oocytes were identified, isolated and stained to assess viability. In all queens, blood samples for plasma progesterone concentrations were collected once a week, from Days -21 to 106. After deslorelin acetate application, four queens had VC and behavior typical of estrus, and one ovulated. Furthermore, ovulation occurred in three queens that did not have VC or behavior consistent with estrus. After the initial ovarian stimulation, all females had anestrous VC during the deslorelin treatment period. Implants were readily removed. Following implant removal, all females responded to treatments to induce estrus and ovulation. There were (mean ± SEM) 13.1 ± 5.5 CL and 8.1 ± 5.5 oocytes per queen; the oocyte recovery rate was 56.8 ± 25.4% and all recovered oocytes were viable. We concluded that deslorelin acetate can be used as a reversible short-term contraceptive in domestic cats, because estrus and ovulation were successfully induced following implant removal.

Histological characterization and immunohistochemical localization of ki-67 and VEGF factors in bitches' corpus luteum at cyclic and early and late gestational diestrous.

The luteal phase on pregnant and non-pregnant bitches is characteristic of this species and resembles significantly with respect to the growth pattern and luteal regression. Histological and immunostaining studies of the corpus luteum (CL) may help to elucidate differences between the CL of pregnant and non-pregnant bitches. The purpose of this study was to characterize histologically and localize by immunohistochemistry the cell proliferation (Ki-67) and vascular endothelial growth (VEGF) factors in the CL of pregnant and non-pregnant bitches. Eighteen bitches were analysed and distributed into three groups: In group I (gestational diestrous), seven bitches were subjected to two inseminations at 4 and 6 days after the pre-ovulatory LH surge and ovariohysterectomized (OSH) at 8-21 days after the first insemination. In group II (cyclic diestrous; control), 6 (Ki-67) or 8 (VEGF) bitches that were determined as non-pregnant were OSH at 12-25 days of the pre-ovulatory LH surge. In group III (late pregnancy), three bitches had their ovary removed during caesarean section at 62-64 days after the pre-ovulatory LH surge. Portions of the ovarian cortex containing CLs were cut and stored for histological and immunohistochemical analysis. Histological evaluation of the ovarian cortex showed a marked similarity in the morphological pattern among the CLs in all three groups. The morphology and expression pattern of VEGF and Ki-67 factors in CLs of cyclic and gestational diestrous bitches were similar but significantly lower than that of late pregnant bitches (p < 0.05).

Progesterone (PR), oestrogen (ER-α and ER-ß) and oxytocin (OTR) gene expression in the oviduct and uterus of pregnant and non-pregnant bitches.

The aim was to assess hormone receptor gene expression in the oviduct and uterus during canine pregnancy. Nineteen pregnant bitches divided into four groups were ovariohysterectomized (OVH) at either day 8, 12, 21 or 60 of pregnancy, and five non-pregnant females underwent OVH 12 days after the pre-ovulatory Luteinizant Hormone (LH) surge and served as controls. RT-qPCR for progesterone (PR), oestrogen (ER-α and ER-ß) and oxytocin (OTR) receptors was performed on the oviduct and uterine tissue. The mRNA PR expression in the uterus during early stages of pregnancy and the luteal phase was higher than at other times. The mRNA ER-ß expression in the oviduct during early pregnancy was less than in non-pregnant bitches. In the uterus, the mRNA ER-ß expression was higher in the initial stages of pregnancy. The ER-α expression was higher in the oviduct and uterus in advanced stages of pregnancy. The mRNA OTR expression in the oviduct was lower than in the uterus in control group. The expression of this receptor in oviduct and the uterus was higher in the final stages of pregnancy, when compared with other phases. These data suggested that the serum progesterone concentrations probably exert a direct control on the PR and ER (α and ß) expression and indirectly on OTR expression in the bitch oviduct and uterus.

Evaluation of sperm DNA peroxidation in fertile and subfertile dogs.

Oxidative stress (OS) has been recognized as one of the most important causes of male infertility. The antioxidant activities of seminal plasma and epididymal fluid are not enough to prevent OS, which can damage sperm membranes and DNA, so antioxidant supplementation has been used as a treatment of male infertility. The aim of this experiment was to evaluate the DNA peroxidation before and after antioxidant supplementation with vitamin C and E in dogs with and without fertility problems. A total of eleven dogs were used and were divided in two groups: fertile group (G1), dogs with normal spermiogram (n = 5); subfertile group (G2): dogs with low sperm count (<20 × 10(6) sptz/ml) and/or more than 30% of total sperm pathology (n = 6). Both groups received 500 mg/day of vitamin C and 500 mg/day of vitamin E for 60 days. A semen sample was collected before (M1) and after (M2) oral supplementation. Samples were analysed for DNA peroxidation by measuring the 8-hydroxy-2'-deoxyguanosine concentration. No significant difference was observed between groups at either time. Oral supplementation with 500 mg/day of vitamin C and 500 mg/day of vitamin E did not change the DNA peroxidation in fertile and subfertile dogs.

Lactate in bitches with pyometra.

Lactate is a compound produced by the anaerobic metabolism of glucose, and hyperlactataemia occurs when the rate of production of lactate exceeds the rate of elimination. This occurs in situations of hypoxia and tissue hypoperfusion. Lactate has been considered a useful prognostic indicator in critically ill patients. Pyometra is a disease of adult female dogs characterized by inflammation of the uterus with an accumulation of exudate, which occurs during the luteal phase. It is one of the most common diseases that occur in the genital tract of female dogs. A total of 31 dogs were diagnosed with pyometra. The diagnosis was confirmed at ultrasonography. Of the 31 dogs, 25 females had open cervix pyometra and six had closed cervix pyometra. Plasma lactate concentrations were determined by an enzymatic colorimetric method. The average concentration (±SD) of plasma lactate in all 31 bitches with pyometra was 3.55 ± 0.46 mm. Healthy dogs had plasma lactate concentrations between 0.3 and 2.5 mm (mean ± SD). Concentrations ranged from 0.8 to 2.9 mm when plasma lactate was measured with a portable device and 0.4-2.6 mm with the blood gas analyser. Even though plasma lactate values vary between several studies and equipment used to measure concentrations, our results for dogs with pyometra are higher indicating hyperlactataemia (Thorneloe et al. , Can Vet J 48, 283-288). Plasma lactate in dogs with closed cervix pyometra was mean ± SD and in dogs with open cervix pyometra, it was mean ± SD. The plasma lactate concentration in dogs with pyometra was higher than in healthy bitches, and there was no influence of patency of the cervix on the concentration of plasma lactate concentrations. Plasma lactate concentrations were similar for animals with open and closed pyometra (3.54 ± 0.52 to 3.64 ± 1.03 mm).

EFFECT OF ESTRADIOL BENZOATE ON OOCYTES/EMBRYOS RECOVERY AND HEMATOLOGICAL PARAMETERS OF MISMATED BITCHES / Efeito do benzoato de estradiol na recuperação de oócitos, embriões e nos parâmetros hematológicos de cadelas recém acasaladas.

Nosso objetivo foi avaliar os efeitos do benzoato de estradiol sobre a taxa de recuperação oocitária e embrionária e sua influência sobre o sistema hematopoiético. Vinte e quatro fêmeas foram utilizadas: GRUPO I – 12 cadelas que receberam uma única aplicação de benzoato de estradiol, dose de 0,2 mg/Kg, via intramuscular, entre o 2º e 7º dia do último acasalamento ou inseminação. GRUPO II - 12 cadelas que receberam solução oleosa diluente, dose de 0,2 ml/Kg em datas correspondentes. As cadelas foram submetidas a ovariohisterectomia e as tubas uterinas e útero lavados, com solução de PBS, álcool polivinil e heparina. Os oócitos e embriões foram quantificados e classificados de acordo com seu estádio de desenvolvimento. O hemograma foi realizado em M1 (antes da aplicação do fármaco), M2 (15 dias após a aplicação do fármaco) e M3 (40 dias após a aplicação do fármaco). Para as variáveis recuperação de estruturas foi utilizado o coeficiente de correlaç&at

Oocyte maturation in bitches

The canine species has been used as an experimental model for preservation of endangered species. Biotechnologies of reproduction, such as in vitro maturation (IVM), have been used to meet this objective. Several protocols for in vitro embryo production (IVEP) in swine and bovine species have been adapted for canids. Ho wever, the highest rate reported for in vitro maturation in canids is only 39%, which is still lower than those in other species. Therefore, current research on assisted reproduction in canids have focused on several IVM protocols, including the addition of proteins, hormones, meiosis inhibitors, growth factors and antioxidants to the maturation media and the determination of suitable timing for culture, so that variables involved in the process can be fine-tuned. This review has the main objective of describing major developments and limitations in the process of oocyte maturation in bitches.

Concentração de lactato e glicemia em cadelas e neonatos nascidos de cesariana / Lactato concentration in bitch and canine neonates born through cesarean section

Avaliaram-se a concentração de lactato e a glicemia em sete cadelas em trabalho de parto submetidas à cesariana e em seus respectivos neonatos. O lactato materno foi mensurado utilizando-se medidor portátil e pelo método enzimático colorimétrico. Nos neonatos avaliou-se também o peso ao nascimento. Os valores de lactato materno e neonatal foram estatisticamente diferentes, sendo mais elevado nos neonatos. Ao nascimento, as cadelas e os neonatos encontravam-se normoglicêmicos, e não se observou correlação entre a glicemia de ambos. Os valores de lactato obtidos pelo o analisador portátil (3,5±0,6mmol/L) foram mais altos do que os obtidos pelo método enzimático colorimétrico (1,6±0,6mmol/L). Observou-se correlação significativa entre o peso do neonato e a concentração de lactato, isto é, os filhotes de menor peso apresentaram maior concentração de lactato.(AU)

This work evaluated the concentration of lactate and blood glucose in seven bitches in labor subject to caesarean section and in their newborns. The lactate concentration was measured using a portable analyzer and enzymatic colorimetric method. In neonates, the birth weight was evaluated. The maternal and neonatal lactate values were statistically different, being higher in newborns. At birth, the bitches and the newborns had normal glucose status, and no correlation was observed between blood glucose in either. The lactate concentration obtained by the portable analyzer (3.5±0.6mmol/L) was higher than that obtained with the enzymatic colorimetric method (1.6±0.6mmol/L). There was significant correlation between the neonate weight and lactate concentration and in puppies with lighter weight there was a higher concentration of lactate.(AU)

Expressão gênica dos REα, REβ e PR em tumores mamários de cadelas por meio do q-PCR / REα, REβ and PR gene expression in mammary gland tumors of female dogs by q-PCR

A expressão de receptores de estrógeno (ER) e progesterona (PR) por meio da técnica de q-PCR foi avaliada em 26 cadelas portadoras de neoplasias mamárias e cinco cadelas sem afecções mamárias (grupo controle). Os resultados mostraram que os três grupos de animais estudados - com tumor maligno ou benigno e controle - expressaram receptores de estrógeno alfa, beta e progesterona. A quantificação relativa mostrou tendência para uma expressão maior de receptores no grupo controle e menor no grupo de animais com neoplasias malignas. Além disso, observou-se expressão maior de ERα em relação ao ERβ, e as neoplasias malignas de origem mista apresentaram maiores concentrações dos receptores PR, ERα e ERβ que as neoplasias de origem epitelial.(AU)

The estrogen and progesterone receptor (ER and PR) expression with the q-PCR technique was evaluated in 26 female dog carrying of mammary tumors and five female dogs without mammary disease (control group). The results showed that the three animal groups evaluated - malignant or benign tumor and control - expressed alpha and beta estrogen and progesterone receptors. The relative quantification showed a tendency for a higher expression of receptors from the control group and smaller in the malignat tumors animal group. Also, there was a major ERα expression regarding to ERβ and the malignat tumors from mixed origin presented higher concentrations of receptors PR, ERα and ERβ, when compared to tumors of epithelial origin.(AU)

Oocyte maturation in bitches

The canine species has been used as an experimental model for preservation of endangered species. Biotechnologies of reproduction, such as in vitro maturation (IVM), have been used to meet this objective. Several protocols for in vitro embryo production (IVEP) in swine and bovine species have been adapted for canids. Ho wever, the highest rate reported for in vitro maturation in canids is only 39%, which is still lower than those in other species. Therefore, current research on assisted reproduction in canids have focused on several IVM protocols, including the addition of proteins, hormones, meiosis inhibitors, growth factors and antioxidants to the maturation media and the determination of suitable timing for culture, so that variables involved in the process can be fine-tuned. This review has the main objective of describing major developments and limitations in the process of oocyte maturation in bitches.(AU)

Imunoistoquímica de útero e cérvice de cadelas com diagnóstico de piometra / Immunohistochemical of the cervix and uterus of bitches diagnosed with pyometra

Analisou-se a piometra de 31 cadelas, de raças e idades variadas, sendo 25 cadelas com piometra de cérvice aberta e seis de cérvice fechada. Após ovariossalpingo-histerectomia, foram coletados fragmentos da cérvice e do útero para a avaliação imunoistoquímica. Foram analisados os receptores de estrógenos α e β, progesterona e colágenos I e III. Foram realizadas imunomarcações em diferentes regiões da cérvice, como o epitélio glandular, o epitélio luminal e o estroma glandular, assim como em diferentes regiões do útero, como o epitélio glandular e o estroma glandular. As imunomarcações de colágenos I e III foram realizadas nas regiões glandular e muscular da cérvice e do útero. Concentrações de receptores de progesterona foram maiores em cadelas com piometra fechada.(AU)

The pyometra in 31 bitches of different breeds and ages, 25 with pyometra cervix open and 6 closed cervix was analyzed. After the ovariohysterectomy procedure, samples were collected from the cervix and uterus to evaluate immunohistochemistry. For immunohistochemical evaluation estrogen receptors α and β, progesterone and collagen I and III were analyzed. Immunostainings were performed in different regions of the cervix such as glandular epithelium, luminal epithelium and glandular stroma, as well as in different regions of the uterus, such as glandular epithelium and glandular stroma. The immunostainings for collagen I and III were performed in muscular and glandular regions of the cervix and uterus. The concentration the progesterone receptors were elevated in bitches from the closed pyometra.(AU)

Ultrastructural characteristics of non-matured and in vitro matured oocytes collected from pre-pubertal and adult domestic cat ovaries.

The present study describes the ultrastructural characteristics of cat oocytes before maturation and after 12- and 24-h in vitro maturation (IVM). Oocytes were recovered from pre-pubertal and adult queen ovaries after ovariohysterectomy and a proportion were stored in glutaraldehyde at 4 degrees C until examination by transmission electronic microscopy (TEM). Those selected for maturation were cultured before TEM in DMEM for 12 and 24 h at 38 degrees C in a humidified environment of 5% O(2), 5% CO(2) and 90% N(2). Specimens were divided into six groups: non-matured oocytes from pre-pubertal queens (PP0), non-matured oocytes from adult queens (A0), 12-h in vitro matured oocytes from pre-pubertal queens (PP12), 12-h in vitro matured oocytes from adult queens (A12), 24-h in vitro matured oocytes from pre-pubertal queens (PP24) and 24-h in vitro matured oocytes from adult queens (A24). Across the treatment groups, it was possible to observe differences in the thickness of the perivitelline space, the penetration of cumulus cell projections forming a junctional complex, distribution and density of small vesicles, lipid droplets, microvilli, mitochondria and cortical granules and variable degrees of development of Golgi complexes. These findings demonstrated that ultrastructural analysis of oocytes matured in vitro is a valuable tool to evaluate oocyte cytoplasmic maturation and that this IVM protocol was efficient in inducing gradual morphological changes necessary for cytoplasmic maturation of pre-pubertal and adult cat oocytes.