Resumo
Background: The use of conventional artificial insemination (AI) in sheep production is usually associated with lower fertility rates when frozen semen is used. Cooled ram semen has been an alternative over frozen semen due to the higher viability, seminal quality and fertility rates following AI. The semen preservation process promotes sperm cell modifications similar to capacitation (capacitation-like) that causes cell damage affecting viability and seminal quality, but such effects are unclear for cooled semen. The aim of this study was to determine the status of sperm cell capacitation (CA) and acrosome reaction (AR) during ram semen processing and cooling under different extenders, dilution factors, and aerobiosis conditions as a function of storage time at 5o C. Materials, Methods & Results: Two consecutive ejaculates per day per male were collected from 2 adult rams by artificial vagina at 48-72 h intervals, in three replications. After macro- and microscopic evaluations, semen was segregated into groups under 3 extenders (Tris-egg yolk or TY, citrate-egg yolk or CY, skimmed milk or SM), 2 dilution factors (1 x 109 or Bi, 100 x 106 or Mi cells/mL), and 2 aerobiosis conditions (aerobic or A, semi-anaerobic or SA). Diluted semen was cooled to 5ºC and stored for up to 72 h, with evaluations every 24 h. Aliquots of fresh ejaculates and of each cooled diluted subgroup, according to extender, dilution, and aerobiosis, were collected at times T0 and T72 for determination of acrosome status and membrane integrity by the chlortetracycline (CTC) and trypan blue-Giemsa stainings, respectively. No differences were detected in sperm cell motility (M) and motility vigor (V) between fresh and diluted semen. After cooling, a significant decrease in M was observed after 48 h in CY and SM compared with fresh semen and 0 h of cooling, while V started to decrease after 24 h in CY compared with TY. Likewise, M/V from different dilutions and aerobic conditions decreased more significantly after 48 and 24 h of cooling, respectively. The sperm capacitation status did not show differences in the proportion of non-capacitated (NCA), CA and AR sperm cells between TY, CY, and SM extenders (NCA: 75.0%, 71.3%, 74.0%; CA: 15.7%, 17.2%, 15.9%; AR: 9.3%, 11.5%, 10.2%) or between Bi and Mi dilutions (NCA: 74.0%, 72.9%; CA: 15.9%, 16.6%; AR: 10.1%, 10.5%), respectively. However, differences (P < 0.05) were observed between A and SA aerobic conditions, with CA (17.0% vs. 15.5%) and AR (11.9% vs. 8.7%) rates being higher in A than SA, respectively, with no differences in NCA (71.1% vs. 75.8%), irrespective of the storage time. Sperm cell viability decreased after 48 h, especially in CY (P < 0.05). Discussion: Ram sperm cells can suffer irreversible damage due to thermal shock during cooling. Egg yolk-based extenders provide phospholipids and cholesterol to protect the sperm cell membrane during the thermal shock caused by the change in temperature. In this study, sperm cells had irreversible decreases in M/V, with increase in acrosome and plasma membrane damage after cooling to 5ºC. The largest and smallest decreases in M and V over time were observed in the CY and TY extenders, respectively. In addition to the extender type, the semen preservation method and storage time promoted changes in the capacitation status, AR and in sperm cell viability, which per se were associated with a decrease in semen fertility. In fact, the proportions of CA and/or AR sperm cells gradually increased over time after dilution and storage at 5ºC, with a negative correlation between sperm cell viability and M/V over time. In summary, extender and cooling time affected mostly M/V, while aerobiosis condition and dilution factor were more associated with acrosome status and sperm survival, with the extender having less impact on the acrosome status as a function of time.
Assuntos
Animais , Masculino , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Preservação de Tecido/métodos , Ovinos , Análise do Sêmen/veterinária , Sobrevivência Celular , Técnicas de Diluição do Indicador , AerobioseResumo
This work aims to report the occurrence of a mixed testicular neoplasm, seminoma associated withsertolioma, in the ectopic testis located in the left inguinal canal of a dog. A 9-year-old male poodle dog wastreated at the Small Animal Clinic of the Veterinary Hospital of the State University of Maranhão (HVU-Uema),presenting thrombocytopenic haemorrhagic purpura and swelling of firm contents in the left inguinal region,with pain on palpation of the area. In the cytology analysis it was observed high cellularity composed by twodistinct cell types. Thus, according to the clinical and cytopathological findings, it was diagnosed Semenomaassociated with Sertolioma. It is an important finding, since the method of diagnosis by cytology is not verysensitive in the joint detection of these two neoplasms.
Assuntos
Animais , Cães , Criptorquidismo/diagnóstico , Criptorquidismo/veterinária , Cães/anormalidades , Tumor de Células de Sertoli/veterináriaResumo
Objective to evaluate the effect of pre-treatment of recombinant bovine somatotropin (rbST) oncumulus-oocyte complexes (CCOs) recovered from OPUs. Using 12 females bovine race Girolando, which theywere divided into three experimental groups: control 0mg, 250mg and 500mg rbST, applied at 12 day intervals.Then, were made five sessions of Ovum Pick Up (OPU) with the aid of ultrasound, with intervals of 7 days. Thevariables studied were submitted to normality test; normal data and standardized by mathematicaltransformations, were subjected to analysis of variance (ANOVA) or parametric test Student-Newman-Keulstocompare means. Obtained mean and standard deviation of the total pattern CCOs and CCOs viable accordingto the following treatments.So, the pre-treatment rbST not influence both in the proportion of CCOs viable andthe morphological quality of CCOs of bovine female.
Assuntos
Feminino , Animais , Bovinos , Bovinos/embriologia , Bovinos/fisiologia , Fase Folicular , Hormônio do Crescimento/análise , Hormônio do Crescimento/uso terapêuticoResumo
This study aimed to evaluate the effect of rbST on in vitro production of Girolanda female embryos.Ovum Pick-Up (OPU) was performed to obtain the cumulus-oocyte complexes (COCs) were subjected to thePIV. Pretreatment of rbST in cows Girolando did not influence the embryo development rate in vitro production.
Assuntos
Animais , Bovinos , Bovinos/embriologia , Hormônio do Crescimento/análise , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/veterináriaResumo
This study aimed to evaluate the biometric and histological aspects of the testicles of horses Baixadeiro.Four stallions were used, with a mean age of 3,88 ± 1,24. The right and left testicles were measured for length,width, height and total scrotal width. The testicular volume was also determined and histological fragmentswere removed parenchyma of testis stained with H-E. There was no statistical difference between the linearmeasurements of the right testis and left (P > 0,05). The weight of the testes showed differences (P < 0,05) dueto the characteristics of the evaluated animals (cryptorchidism, testicular asymmetry). Histologically, bothshowed edema and hemorrhage as testicular degeneration. Thus, the animals showed values of scrotalcircumference lower than expected for the species, and testicular diseases, not being considered fit toreproduction.