1,721,315 research outputs found
New aspects of boar sperm encapsulation
No full textThe study takes into account the main steps and techniques for boar semen encapsulation, to optimize the instrumental insemination interventions. The use of cheap, biocompatible polymers as alginate can assure a regular, constant release of spermatozoa in the sow reproductive system, avoiding the double/triple intervention of insemination and reducing the employ of disposable materials. The encapsulation/microencapsulation of semen can therefore be the starting point of new, innovative systems of pig reproduction management
Fetal and maternal heart rate ratio in pregnant bitches: effect of gestational age and maternal bodyweight
No full textIntroduction and aim. The most widely used method to evaluate fetal health is the monitoring of fetal heart rate (FHR). In case of fetal distress a bradycardia is commonly detectable, but the relationship between FHR and maternal heart rate (MHR) has been poorly investigated (1). Pregnancy induces some hemodynamic changes and MHR tends to be higher to ensure adequate blood supply to the fetus (2). However, several factors such as maternal age, breed, bodyweight, temperament could also affect the MHR (3). The availability of reference values of the ratio FHR/MHR, could better contribute to the evaluation of the fetal health at different gestational ages than the single FHR values. For this purpose, the trend of FHR, and FHR/MHR ratio in bitches of different pre-gestational bodyweight was evaluated during uncomplicated pregnancies.
Materials and methods. Pregnant bitches (n=17) of different breeds, pre-gestational bodyweights (5.8-68 kg) and ages (2-7 years) were examined by ecocolordoppler (SonoAce 8800, Medison Co. Ltd., Seoul, Korea) twice a week (5 bitches) from day 21 after ovulation (progesterone 4-10 ng ⁄ml), and at week 4, 7, and 9 of pregnancy (12 bitches). To reduce and control the stress-effect induced by the restraint, MHR was evaluated at the aortic valve three times: at the beginning of the examination, after 10 minutes and at the end of the examination. The FHR of at least 3 different puppies (in litter size >3) was recorded. Only data from uncomplicated pregnancies (n=11) were included in the statistical analysis. The relationship between FHR, and FHR/MHR ratio, and independent variables (pre-gestational maternal bodyweight, and gestational age, in terms of days from parturition) was analyzed by a quadratic regression (p≤0.05).
Results. Fetal heart rates and FHR/MHR ratio significantly fitted a multiple quadratic regression for all independent variables (p<0.02 and p<0.05, respectively); FHR increased from 35 days to 20 days before parturition, and then a decreasing pattern until parturition followed. Higher values of FHR were observed in bitches of lowest and highest bodyweight. As seen for FHR, the FHR/MHR ratio resulted higher in low and high bodyweight, and it reached the maximum values at about 20 days from parturition. The FHR/MHR ratio was well expressed by a quadratic law, in terms of pre-gestational bodyweight and gestational age. The equation derived was as follows: z= 1.8284-0.0137x + 0.00014x2+0.05071y-0.00099y2,where z = FHR/MHR ratio, x = pre-gestational maternal bodyweight (kg), y= days from parturition.
Conclusion. This study suggests that the maternal pre-gestational bodyweight and the gestational age influence FHR and MHR. The patterns of FHR and FHR/MHR ratio were similar, but the ratio better describes the effect of the independent variables on the data. The highest significance of FHR/MHR compared to FHR alone, encourages the application of this ratio to evaluate fetal wellbeing. The derived equation could be applied in clinical practice to obtain the expected values in healthy pregnancies.
References. 1) Johnston et al., Canine and Feline Theriogenology 2001; WB Saunders, Philadelphia. 2) Lucio et al., Reprod Dom Anim 2009;44(suppl 2):133-6. 3) Hezzell et al., JSAP 2013;54:318-24. 4) Assali et al., Am J Obstet Gynecol 1977;129:748-59
Ultrasonographic Study of Deep Portion of Diencephalo-Telencephalic Vesicle for the Determination of Gestational Age of the Canine Foetus
No full textThe aim of this study was to evaluate the accuracy of
ultrasonographic measurement of the deep portion of
diencephalo-telencephalic vesicle (DPTV) in the prediction
of delivery date in different size bitches. The effects of litter
size and foetal sex ratio on the accuracy were also investigated.
For this purpose, the growth curve of DPTV was
derived in large size dogs (26–40 kg) and the results of the
accuracy of the prediction were compared with those
obtained in small (£10 kg) and medium (11–25 kg) size dogs
by the application of the equations derived from the growth
curve previously described. Ultrasonographic examinations
were performed once a week during the second half of
pregnancy in seven large size bitches (26–40 kg body weight).
A linear regression model was adopted to analyse the
relationship between the DPTV mean values and the days
remaining to parturition. The results of regression analysis
indicated that DPTV measurement in large size dogs is
significantly and linearly related to the gestational age.
Ultrasonographic measurements of DPTV were also performed
during pregnancy in different size bitches with
unknown breeding dates. Although the results indicated a
similar accuracy of the prediction of the date of parturition in
the different sizes of bitches, a higher accuracy was obtained
in normal and large litter size compared with small litters.
Foetal sex ratio did not affect the accuracy. In conclusion,
this study demonstrated that the accuracy of the prediction of
parturition day obtained by ultrasonographic evaluation of
DPTV growth is reliable when specific formulae for different
size dogs are applied. It should be noted that although foetal
sex ratio does not affect the accuracy, the prediction could be
less accurate when a small litter is present
Feto-maternal heart rate ratio in pregnant bitches : effect of gestational age and maternal size
No full textFew information is available on parameters that can be used to objectively assess the foetal health during canine pregnancy. To identify a reliable parameter for the evaluation of foetal well-being, the effect of pre-gestational maternal bodyweight and gestational age on foetal heart rate (FHR) and on feto-maternal heart rate ratio (FHR/MHR) was investigated. Seventeen client-owned pregnant bitches of different pre-gestational maternal bodyweight were examined by serial echo colour Doppler. Only data from 11 uncomplicated pregnancies were included in the statistical analysis. The relationship between FHR, and FHR/MHR, and independent variables was analysed by polynomial regression (p ≤ .05). The FHR and the FHR/MHR significantly fitted a multiple quadratic regression for all independent variables. They both increased from 35 to 20 days before parturition and then a decreasing pattern followed. Higher values of both parameters were observed in bitches of lowest and highest bodyweight. Patterns of FHR and FHR/MHR were similar, but the ratio better describes the effect of the independent variables on the data. Thus, the highest significance of FHR/MHR compared to FHR alone encourages the application of this ratio to evaluate foetal well-being. The equation derived by the regression analysis of FHR/MHR could be applied in clinical practice to obtain its expected values in healthy pregnancies
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Somministrazione di PGF2α dopo il parto nella bovina da latte : effetti sulla concentrazione ematica di idrossiprolina
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Relationship between pharmacological induction of estrous and/or ovulation and twin pregnancy in the Thoroughbred mares
No full textThe aim of this study was to evaluate the possible relationship of pharmacological induction of estrous and/or ovulation with the occurrence of twin pregnancies in Thoroughbred mares. Out of 680 mares, 356 received one of the following treatments during the estrous cycle in which they became pregnant: injection of 0.5 mg of cloprostenol at the ultrasonographic detection of a CL (n=86); injection of 5000 IU human chorionic gonadotropin (hCG) immediately before mating (n=221); injection of 0.5 mg of cloprostenol at the ultrasonographic detection of a CL plus injection of 5000 IU hCG immediately before mating on cloprostenol-induced estrous (n=49). The other 324 mares, not treated for induction of estrous or ovulation in the estrous cycle resulting in pregnancy, were used as control group. The occurrence of twin and single pregnancies in treated and control mares underlines that the percentage of twin pregnancy in treated mares (16.6%) was statistically significantly higher (p<0.0001; odds ratio, OR=2.87) than the percentage of twinning in the control group (6.5%). Comparison of the occurrence of twins between treatments revealed a statistically significant difference between mares treated with hCG alone compared to animals given prostaglandin F2α(PGF2α) plus hCG. The results show a statistically significant difference for each treatment compared to controls, with the least difference (p<
0.05; OR=2.18) for the comparison between hCG treatment group and controls, a significance of p<0.01; OR=3.05; for the comparison between PGF2α treatment and controls, and a highly statistically significant difference (p<0.0001; OR=6.37) for the comparison between PGF2α plus hCG-treated animals and controls
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