Effects of extender, cryoprotectants and thawing protocol on motility of frozen-thawed stallion sperm that were refrozen for intracytoplasmic sperm injection doses.

We examined the effects of different freezing extenders, cryoprotectant agents (CPA) and initial thawing temperatures for preparing doses of refrozen stallion sperm for intracytoplasmic sperm injection (ICSI). Single ejaculates, from twelve stallions, were frozen in lactose-EDTA-egg yolk extender (LE) with 5% glycerol. In experiment 1, sperm were initially thawed to 5 °C or 37 °C, before being diluted in LE or skim milk-egg yolk extender (SMEY) containing either 5% glycerol (GLY), 5% methylformamide (MF) or 5% of a combination of both (GMF). In experiment 2, frozen sperm were initially thawed to 5 °C, diluted and refrozen in SMEY containing 2, 4, 6 or 8% GLY or GMF. In Experiment 1, sperm motility was reduced after each cryopreservation cycle (P < 0.05). Extender type did not affect motility after refreezing (P > 0.05), but sperm initially thawed to 5 °C exhibited higher motility than sperm thawed to 37 °C (P < 0.05). In addition, sperm refrozen in SMEY containing MF or GMF exhibited higher motility than sperm refrozen in GLY alone (P < 0.05). In experiment 2, there was an interaction between CPA and CPA concentration (P < 0.05). Sperm refrozen with GMF had higher motility than refrozen sperm with GLY (P < 0.05), and while GLY concentration did not affect post-thaw motility (P > 0.05). Sperm refrozen with 6 or 8% GMF exhibited the highest motility (P < 0.05). In conclusion, sperm motility is best maintained when thawing and refreezing stallion sperm in low sperm concentration ICSI doses by initially thawing the sperm to 5 °C and diluting the sperm in a freezing extender with 8% GMF.

Bacteriological, cytological and histopathological evaluation of the reproductive tract of slaughtered cows / Avaliação bacteriológica, citológica e histopatológica do trato reprodutivo de vacas abatidas

Reproductive diseases, mainly endometritis, are important hurdles in cattle raising, In the current study we evaluated gross, bacteriological, cytological, and histological findings from selected sites of the genital from 23 slaughtered cows and tested whether there is an association between these findings and the probability of reaching a reliable diagnosis. The results from the examinations of macroscopic aspects of uterine secretions, the cytological, bacteriological, and histopathological findings were then correlated. There was no significant correlation (P>0.05) of the statistical data from different parts of the genital tract. Trueperella pyogenes and Escherichia coli were isolated from the vagina in 3/23 cases. In only 2/23 samples Enterococcus faecalis and a gram-negative, oxidase-positive bacteria were isolated from the cervix uteri. Only Staphylococcus epidermidis, in 1/23 case, was isolated from the uterus. Histopathological findings in uterus from samples of Groups II (moderate lesions) and III (severe lesions) did not translated in grossly visible changes. Samples from reproductive tracts with secretion in the vagina and cervix uteri had no detectable changes in the other parameters analyzed from this portion. Uterus with positive bacterial culture had evidence of ascendant inflammation judging by the high granulocyte count in the three analyzed portions. This study reinforces that vaginitis and cervicitis in the cow diagnosed only by clinical examination does not reflect the real status of the uterine health. For this reason, treatment of uterine disorders should be conducted based on reliable tests to determine the appropriate therapy for each situation.(AU)

Doenças reprodutivas causam altas perdas econômicas nos rebanhos bovinos, sendo a endometrite uma das alterações mais relevantes. Os objetivos desta pesquisa foram avaliar a associação dos achados fisiopatológicos em exames macroscópicos, bacteriológicos, citológicos e histopatológicos nas porções do trato genital de 23 vacas abatidas, bem como avaliar a necessidade de associação destes exames para efetuar diagnóstico fidedigno. A avaliação macroscópica da secreção, os exames histopatológico, citológico e as bactérias identificadas foram correlacionados. Não houve associação (P>0,05) dos resultados nas diferentes porções do trato genital. Na vagina foram isoladas as bactérias Trueperella pyogenes e Escherichia coli. Na cérvix, em apenas 2/23 (8,6%) amostras isolou-se Enterococcus faecalis e gram negativo oxidase positiva. No útero houve isolamento apenas da bactéria Staphylococcus epidermidis. As amostras histopatológicas classificadas em grupo II e III não apresentaram alterações detectadas no exame macroscópico. As amostras com secreção não fisiológica na vagina e cérvix não apresentaram alterações nos outros exames na porção uterina. A amostra com cultura bacteriológica positiva no útero demonstrou uma infecção ascendente através da alta contagem de granulócitos nas três porções analisadas. O presente estudo reforça o conceito de que a vaginite e cervicite diagnosticadas pelo exame clinico na vaca não retratam o real status da saúde uterina e por esta razão, o tratamento do útero deve ser conduzido com critério, alicerçado nos exames complementares para definir a terapia adequada para cada situação.(AU)