No abstract

Summary: Reproductive biotechnologies such as cooling and freezing semen are employed in order to obtain genetic enhancement in domestic animal breeds. However, cryopreservation of donkey semen, as in several other domestic mammalian species, has not yet reached a standard procedure that provides satisfactory and repeatable results, as in bulls. Despite there are over 43 million donkeys worldwide, there are only few studies about donkey semen preservation. The aim of this study was to evaluate the predictive potential of hypo-osmotic test and the supra vital staining in raw semen to be used as indicators for donkey semen freezability. Ejaculates were collected twice per week from 10 fertile donkey stallions. Volume, appearance (color and density), concentration, total motility, morphology, sperm viability (supra vital staining -eosin-nigrosin-EN) and plasma membrane integrity (hypo-osmotic swelling test -HOST) were evaluated in raw semen. After dilution the samples were centrifugated and sperm pellets were resuspended in a freezing extender to a concentration of 50 ×10 6 cells/mL. Aliquots were packed into 0.5 mL straws and placed in the refrigerator (5°C) for 20 min. Subsequently these straws were kept above liquid nitrogen for 20 min, then plunged into nitrogen and stored in a holding tank. Post-thaw analyzes consisted in computerized analysis of sperm movement characteristics, sperm viability (EN), plasma membrane integrity (HOST and fluorescent probe) and acrosome membrane integrity using fluorescent probe. High correlation was found between EN (0.93) and HOST (0.69) in raw semen when compared with total motility after frozen-thawed semen. Low correlation was found between EN and HOST when compared with plasma and acrosomal membrane integrity in post-thawed with fluorescent probes. Since sperm motility is one of the key parameters to evaluate the quality of frozen semen, hypo-osmotic test and supra vital staining can be considered good predictive indicators in raw semen for donkey semen freezability.Keywords: Equus Asinus, cryopreservation, eosin-nigrosin, plasma membrane integrity, semen, reproduction Citation: Arruda de Oliveira R., Batista Silva Teixeira A., Almeida Pignataro T., Freitas M. L., Castro Alves Teixeira H., de Oliveira Carvalho J., Alves Nune Dode M., Pivato I., Budik S. (2017) Evaluation of Hypo-osmotic swelling test and supra vital staining technique as indicators for donkey semen freezability. Pferdeheilkunde 33,[159][160][161][162][163][164]

The objective of this study was to evaluate hormone and energy profiles in the postpartum period and to correlate these profiles with the resumption of ovarian cyclicity, as well as characterizing the postpartum short estrous cycle of Curraleiro Pé-Duro cows. Twelve Curraleiro Pé-Duro cows were examined via rectal palpation and ultrasound at 10 days postpartum, and subsequently examined daily to evaluate the resumption of ovarian cyclicity as well as every five days in order to evaluate uterine involution. Upon analysis of the data, it was possible to observe the formation of two distinct groups, one of which was comprised of those animals which returned to cyclicity within 60 days postpartum and another comprised of those animals which returned to cyclicity more than 105 days postpartum. Therefore, animals were divided into two groups; precocious, designated Ov Group, and delayed, designated NOv Group, wherein the cut-off time for all tests was 60 days postpartum. Statistically significant differences (P < 0.01) between the groups occurred only regarding the day of 1st ovulation, which in the Ov Group averaged 51.4 ± 9.3 days and in the NOv Group averaged 138.3 ± 19.8 days postpartum. The other postpartum short estrous cycle variables assessed did not show statistically significant differences (P > 0.05) between the groups. NEFA, BHBA and thyroxine concentration levels did not differ (P > 0.05) between the groups in any of the statistical analyses. However, in the analysis comparing growth curves, triglycerides levels were higher for the Ov Group (P = 0.04) and cholesterol levels were higher for the NOv Group (P = 0.02). In this experiment, a small influence of a negative energy balance between the groups was observed, suggesting that these animals can present significant genetic variability due to natural selection, as evidenced by the formation of groups of animals with precocious and delayed reproductive characteristics.

This study aimed to compare the effects a commercial milk-based extender and a self-made egg yolk extender had on the quality of canine semen stored at two different temperatures, 5ºC or 15ºC. The ejaculate obtained was split into two aliquots of equal volume and diluted with the milk or egg yolk extender. The final concentration was 100×106 spermatozoa/mL. Diluted semen was placed in transport containers and maintained at final storage temperatures of 5ºC and 15ºC. The quality of the chilled semen was assessed 12, 24, and 36 hours after storage. Semen diluted with the milk extender had higher motility, vigour, and plasma membrane integrity (p<0.05) of the spermatozoa than that diluted with the egg yolk extender. No difference in the semen quality was observed between the stored temperatures in both the groups. The difference observed between the extenders could be due to the standard formulation of the commercial milk extender and the presence of glucose in the mixture. In conclusion, the milk extender was better than the egg yolk extender at preserving the motility, viability, and membrane integrity of chilled canine semen for up to 36 hours. The storage temperature did not seem to affect the semen quality, suggesting that canine semen can be refrigerated at 15ºC.

The purpose of this study was to evaluate embryo production and embryonic quality of locally adapted Curraleiro Pé-duro cows, using protocols with different progesterone exposure. Cows were divided in three groups: Control, P24 and P36. All cows had the estrus previously synchronized and in the fifth day of the estrus cycle, the cows of the groups P24 and P36 received an intravaginal progesterone device and estradiol benzoate. Starting from the ninth day of the cycle, all cows received eight decreasing doses of FSH and two doses of Dcloprostenol together with the two last doses of FSH. Treatments P24 and P36 had the progesterone device removed 24 and 36 hours after the first application of D-cloprostenol, respectively. All cows received lecireline in the thirteenth day, with the inseminations accomplished 12 and 24 hours later. There was no difference (P > 0.05) for superestimulatory response among treatments. The number of total structures was greater (P < 0.05) in P24 than in the Control and the number of viable structures was greater (P < 0.05) in both P24 and P36 than in the Control. The use of exogenous progesterone in superovulation protocols improved embryo production and quality of locally adapted Curraleiro Pé-duro cows.

Due to the scarcity of information on Breton horses, the objective was to study hematobiochemical values of this breed. Blood samples were collected from 29 Bretons, males and females, of different ages, in Brasília-DF, distributed into groups, according to age, without distinction of sex (G1): animals from 4 to 9 years old (n=16) and (G2): from 10 to 26 years old (n=13). The horses were also distributed into males and females for comparisons between the sexes. Values for red blood cells, hemoglobin, creatinine, and urea were statistically higher in females. Fibrinogen was higher in males. Lymphocyte values were higher in G1, but mean corpuscular volume, monocytes, neutrophils, and GGT in G2 were higher than G1. The hematocrit value differed between the ages of the females and was higher than that of the males, while the older male animals showed higher values than the young animals. Females presented lower platelet values than males, with older females having higher platelet values than younger females, in the same way as males. G1 females had the highest leukocyte values. The leukocyte values in males of G2 were higher than those of G1. This same behavior occurred for lymphocytes, eosinophils, and creatine kinase. Considering the albumin and aspartate aminotransferase variables, females had the highest values in the group of animals aged 4 to 9 years. Bretons are considered cold-blooded animals, which is consistent with the observed blood count values. However, it is concluded that these horses have biochemical values similar to warm-blooded breeds.

RESUMO Três experimentos foram realizados para adaptar um protocolo de sincronização de estro e da ovulação para ser utilizado em programas de inseminação artificial em tempo fixo (IATF) em vacas taurinas tropicalmente adaptadas. No Exp. 1 (crossover), vacas pluríparas Curraleiro Pé-Duro (n= 12) receberam um dispositivo intravaginal contendo 1g de P4 por oito dias e 2mg de BE intramuscular (IM) no momento da inserção do dispositivo (dia 0). No dia da remoção do dispositivo (dia 8), as fêmeas receberam 150μg de D-cloprostenol sódico e 300UI de gonadotrofina coriônica equina (eCG) IM, sendo, então, divididas aleatoriamente para receber 1mg de BE no dia 8 (BE8) ou 1mg de BE no dia 9 (BE9). A aplicação de BE no D9 atrasou a ovulação em aproximadamente 15 horas (P<0,05). No Experimento 2, foram avaliados protocolos com oito (P4D8) e nove dias (P4D9) de exposição à progesterona, resultando em parâmetros de desenvolvimento folicular e luteal semelhantes entre os tratamentos (P>0,05). No Experimento 3, os protocolos hormonais de IATF BE8 e P4D9 foram testados para a taxa de prenhez, alcançando 23% (10/43) e 20% (9/45), respectivamente (P>0,05). Embora o grupo P4D9 tenha mostrado avanço na proporção de animais que responderam ao protocolo quando comparado ao protocolo BE8, este não se refletiu em melhora na taxa de prenhez.

O desenvolvimento da produção de gametas femininos (gametogênese) ocorre de forma interessante, pois seu processo depende de diversos fatores combinados. Esta revisão abordará esses mecanismos morfofuncionais do ovário e a foliculogênese, correlacionando a função dos fatores de crescimento ligados à Insulina (IGFs) que irão influenciar na produção de hormônios esteroides, na manutenção da maturação folicular, e ainda elucidar como a dieta alimentar auxilia melhor nessas fases. Além disso, com as novas pesquisas em reprodução animal, é importante enfatizar o papel e auxiliar os Fatores de Crescimento Insulínicos durante este processo fisiológico, mostrando todo o seu potencial para uma dinâmica folicular mais eficiente em qualquer espécie.