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The aim of this study was to evaluate powdered coconut water extender (ACP-106c; ACP Serviços Tecnológicos Ltda, ACP Biotecnologia, Fortaleza, Ceará, Brazil) as a diluent for freezing dog semen and the fertility after vaginal insemination of semen frozen therein. Ten ejaculates were collected from five dogs, evaluated fresh, diluted in ACP-106c, 10% egg yolk and 6% glycerol, cooled and frozen. In the first phase of the study, straws with frozen semen were thawed and immediately subjected to the same analysis as the fresh semen and, in addition, to Computer-Assisted Semen Analysis (CASA). In phase 2, 10 bitches that had been subjected to natural breeding during a preceding oestrous cycle were vaginally inseminated with thawed semen that had been re-diluted in ACP-106c. After thawing, a mean of 77% sperm motility was obtained through subjective analysis and 77.3% through CASA. Following artificial insemination, a 60% pregnancy rate was observed, resulting in a 50% parturition rate and a mean litter size of 3.4 (SEM 0.6), with 47.1% males and 52.9% females. ACP-106c can be successfully used for freezing canine semen, and vaginal deposition of such semen yields similar pregnancy rates to those reported in other studies.

The objective was to determine the effect of powdered coconut water extender (ACP-106c) on the proportion of female puppies born. Twenty French Bulldog bitches were subjected to natural mating (NM) and, during the subsequent two estrus periods, were bred by intravaginal artificial insemination (AI), using chilled semen (from the same males) diluted in Tris-egg yolk (AI-Tris) or ACP-106c (AI-ACP-106c). Fresh semen was cooled to 5 °C and maintained at that temperature for 6 h, rewarmed (37 °C for 30 s), and used for AI. Pregnancy and whelping rates following NM were both 100% and were both 90.0% following AI with either extender. Litter size (mean ± SD) was 5.4 ±1.1, 4.7 ± 2.0, and 5.1 ± 2.0 (P > 0.05) for NM, AI-Tris, and AI-ACP-106c, respectively. Furthermore, for these groups, the number of female vs. male puppies born were 2.6 ± 0.6 vs. 2.8 ± 1.0, 2.2 ± 1.0 vs. 2.5 ± 1.1, and 3.4 ± 1.6 vs. 1.8 ± 1.2 (P < 0.05 for AI-ACP-106c only). In conclusion, our hypothesis was supported; AI of semen in ACP-106c extender resulted in a significantly higher proportion of female puppies. Furthermore, this extender yielded acceptable litter size and rates of pregnancy and whelping.

The objective was to assess the effect of adding various concentrations of dimethylformamide on characteristics of canine semen diluted in powdered coconut water (ACP-106C; ACP Biotecnologia, Fortaleza, CE, Brazil) and frozen at −196°C. Fifteen ejaculates were collected by manual stimulation from five adult Boxer dogs. The sperm-rich fraction was diluted in ACP-106C (ACP Biotecnologia) containing 10% egg yolk and divided into four aliquots. The cryoprotectants used for each aliquot were 6% glycerol (control group; CG) or 2%, 4%, or 6% dimethylformamide (DF2, DF4, and DF6, respectively). After thawing, total motility (mean ± SEM) for CG (58.4 ± 24.6) was higher (P < 0.05) than that of the other groups (2% dimethylformamide, 24.4 ± 12.3; 4% dimethylformamide, 26.5 ± 16.1; and 6% dimethylformamide, 21.7 ± 17.9). Furthermore, there was a greater percentage of fast, average, and slow moving sperm (assessed with computer-aided semen analysis; CASA) in CG in comparison with the other three groups. Therefore, based on concentrations tested in this study, dimethylformamide, together with ACP-106C (ACP Biotecnologia) and 10% egg yolk as a diluent, yielded unsatisfactory in vitro results for freezing canine semen.

Background: Canine leishmaniasis (CanL) is caused by an obligatory intracellular parasite of Leishmania genus that affects organs and tissues. Several studies evaluate the role of reactive oxygen species (ROS) in the pathogenesis of many diseases. The overproduction of ROS on infectious diseases can induce an imbalance between oxidants and antioxidants at cellular or systemic level. Thus, the aim of this study was to evaluate the activity of antioxidant enzymes in CanL.Materials, Methods & Results: Females (n = 17) and males (n = 10), at different ages and with different weight, were selected for this study. Dogs were divided into two groups according classical clinical signs and sorological test to CanL. Animals were considered infected based on indirect immunofluorescent assay and ELISA titration ≥ 1:40. Group B (n = 15) composed by positive dogs to CanL from Zoonosis Control Center of Fortaleza (Ceará, Brazil) and group A (n = 12) was composed by dogs from private kennel that were serologically negative to L. infantum and had absence of clinical signs to CanL. Blood sample were collected for evaluation of hematological and biochemical parameters and glutathione peroxidase (GPx) and catalase (CAT) enzymatic activity. Data were analyzed by Student’s t-test and Pearson correlation coefficient (P < 0.05). Total proteins (TP, mg/dL) and alkaline phosphatase (ALP, U/L) were increased (P < 0.05) on group B (8.2 ± 1.2; 165.4 ± 46.4) when compared to group A (6.5 ± 1.1; 109.1 ± 38.3), respectively. Hemoglobin (Hb; g/dL) and hematocrit (Hct; %) were decreased (P < 0.05) on Group B (14.7 ± 1.8; 48.2 ± 5.7) when compared to group A (16.5 ± 1.3; 52.1 ± 2.4), respectively. Group B presented CAT (U/g Hb) and GPx (mU/mg Hb) lower (189.4 ± 90.4; 3,609.6 ± 1,569.1) than group A (326.6 ± 104.5; 5,055.6 ±1,569.1), respectively (P < 0.001). Positive correlation was observed between RBC and CAT; however, it was not significant.Discussion: Organisms require a good defense system in order to revert the overproduction of free radicals and consequently the injuries caused by them. This is possible through the production of antioxidant agents, which act on oxidative prevention and on tissue and cellular regeneration, by taking the reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) enzymes in the frontline. Erythrocyte changes promoted by CanL suggest possible correlation between anemia and the appearance of clinical signs, which in many cases is not seen. Erythrocytes contain SOD, CAT and GPx enzymes, thus, changes in these cells will reflect on the activity of these enzymes. In our results only CAT showed positive correlation with erythrocyte count, however it was not significant. GPx activity was lower (P < 0.001) in infected dogs than control group. This result agrees with another study, which showed a decrease in GPx levels in CanL, although it was not significant. However, it was found a positive correlation (P < 0.001) between erythrocytes and GPx activity and between hemoglobin and GPx activity in animals with leishmaniasis. These results suggest that the reduction in detoxification activity can be related to the decrease in erythrocyte count and that the GPx activity depends on the control mechanism of the antioxidant system in CanL. Furthermore, this result could be associated with decrease of blood cell count in animals with CanL, once GPx is an erythrocyte enzyme, which plays an important role in hemoglobin protection against oxidative damage. This study was carried out in naturally infected dogs with L. infantum. In conclusion, CAT and GPx activities are relate to oxidative stress induced by L. infantum infection and can be used as biomarkers on CanL.

Semen was collected by digital manipulation from six adult dogs. The second fraction of the ejaculate was used in this study. The semen was assessed by macroscopic and microscopic criteria 1 min after collection, first dilution, cooling, glycerol addition and thawing. Experiments were conducted to compare the effect of three different concentrations of glycerol in coconut water extender. The freezing method employed was that one described for caprine semen with slight changes. Semen was thawed at 37 degrees C for 1 min. Spermatozoal motility after thawing was 49.2+/-26, 44.2+/-18.3 and 35.8+/-26.8% for groups with 4, 6 and 8% glycerol, respectively. The vigor after thawing was 2.6+/-1.1, 2.7+/-1.0 and 2.1+/-1.2 for these groups, respectively. There was no difference among groups in motility and vigor. However, a smaller percentage of total and secondary abnormalities was observed using 6% glycerol in coconut water extender. In conclusion, the three glycerol concentrations (4, 6 or 8%) can be used successfully in cryopreservation of canine semen using a coconut water extender.

O presente trabalho objetivou avaliar a eficiência do diluidor à base de água de coco acrescido de ácido 3-indol acético (AIA) e gema de ovo na conservação do sêmen canino a 37ºC. Coletou-se o sêmen de seis cães adultos por manipulação digital, fracionando-o em três alíquotas. Procedeu-se a diluição do sêmen com o diluidor à base de água de coco (grupo A), com este acrescido de 4% de AIA (grupo B) e, com o mesmo acrescido de 20% de gema de ovo e 4%AIA (grupo C). Avaliou-se a motilidade, o vigor e a percentagem de alterações morfológicas espermáticas imediatamente após a coleta e periodicamente durante 180 minutos (T0, T5, T15, T30, T60, T90, T120, T180), avaliando-se também a taxa de degradação média de motilidade espermática (TDM). Os diluidores foram comparados pelo teste de Whitney-Mann (P

A estocagem do sêmen por um longo período, permitindo o seu posterior uso representa uma importante ferramenta para criadores que desejam resguardar o potencial genético de seus reprodutores. O objetivo do presente trabalho foi avaliar o efeito da água de coco, gema de ovo e glicerol sobre o resfriamento e a criopreservação de sêmen canino. A fração espermática do ejaculado de 12 cães foi avaliada macro e microscopicamente e, em seguida, dividida em quatro alíquotas, submetidas à congelação em quatro diluidores, sendo todos à base água de coco e diferindo quanto à presença ou não da gema de ovo e glicerol. Durante o resfriamento, não se observou diferença entre os grupos, entretanto, após o congelamento e descongelamento, o diluidor adicionado de gema de ovo e glicerol (ACGG) foi superior aos demais quanto à motilidade, vigor e morfologia espermática. Nesse grupo, os valores de motilidade (%), vigor (0-5) e alterações morfológicas totais (%) após a descongelação foram 56,7 ± 16,1, 3,4 ± 0,5 e 23,8 ± 8,4, respectivamente. Diante dos resultados, concluiu-se que a adição de gema de ovo e glicerol ao diluidor foi necessária para a preservação da qualidade espermática após criopreservação de sêmen canino.

The objective of this study was to describe the sexual characteristics of domestic queens kept under natural equatorial photoperiod conditions without mating. Estrous signs were detected in 25 pubertal queens by manual stimulation and by exposure to a tomcat twice daily for 6 months (January to June). The signs observed were tail deflection, spinal flexion, rubbing or rolling, vaginal discharge, vocalization, treading of the hind legs, body or tail tremor and rigidity, blow or scratches, and discomfort on manipulation. The queen was considered in estrous when neck grip, tail deflection and attempted penile intromission by the male were allowed after mounting. From 187 cycles, there were (mean +/- S.E.M.) 7.5 +/- 0.7 cycles detected per queen; the duration of the cycle, estrus and non-acceptance were 18.1 +/- 0.9, 7.9 +/- 0.5, and 10.3 +/- 0.9 d, respectively. Queens always maintained some signs of sexual behaviour; they remained ambivalent for no more than 24 h at a time. It was noted that 85.3% of the observations of body or tail tremor and rigidity were made during estrus; therefore, these signs were considered characteristic of sexual receptivity. There was no evidence of prolonged anestrus or of a circannual pattern to estrus cyclicity.