1,720,990 research outputs found
Reproductive and dairy performances of Thai swamp buffaloes under intensive farm management
Abstract
In this study the reproductive and dairy performances of swamp buffaloes under intensive farm conditions were evaluated. The data of reproduction and milk production were collected from forty-eight swamp buffaloes during the period of 2001 to 2010. The reproductive and dairy performances were analyzed as mean±SD of each index. The age at first calving was 47.1±8 months and the gestation period was 321.4±11.3 days. The service per conception was 3.5±2.5, with insemination by both natural and artificial mating. The calving interval and the days open were 486.2±75.02 and 166.2±69.7 days (n=99), respectively. Additionally, there was a large increase in primiparous and aging cows. The number of conceptive cows rose significantly in November of every year, which reflects a similar period of peak milk production. The dairy performance index such as the lactation period (127.5±104.6 days), the milk production (2.0±0.9 kg/cow/day) and the milk yield (255±209 kg/lactation) were quite low. In conclusion, postpartum cows in this study had low reproductive performances which could indicate that the age at first calving, service per conception and days open in primiparous cows should be improved. Moreover, the low milk production and short lactation period found in this study suggest that swamp buffalo may not be suitable for milking
Effect of short (10-or 12-day) or standard (14-or 18-day) periods of estrus suppression with allyl trenbolone on estrus synchronization and fertility in pubertal gilts
Abstract in English, Spanish and French.Allyl trenbolone was fed at 20 mg per day for 10, 12, 14, or 18 days, with two 75-µg injections of D-cloprostenol at last feeding at 10 or 12 days to synchronize estrus in gilts. There were no treatment effects on farrowing rate or subsequent litter sizes. = Se administró allyl trembolona en el alimento a 20 mg por día por 10, 12, 14, ó 18 días, con dos inyecciones de 75 µg de D-cloprostenol en el último alimento a los 10 ó 12 días para sincronizar el estro en hembras primerizas. No hubo efecto del tratamiento en el porcentaje de fertilidad o en el tamaño de camada subsecuentes. = L’allyle de trenbolone a été administré par la nourriture à une dose de 20 mg par jour pour 10, 12, 14, ou 18 jours avec deux injections de 75 µg de D-cloprosténol au moment du dernier repas à 10 ou 12 jours afin de synchroniser l’œstrus chez les cochettes. Aucun effet de traitement ne fut noté sur les taux de mise-bas ou la tailles des portées subséquentes.F. De Rensis, C. Mazzoni, R. Saleri, M. Techakumphu, R. N. Kirkwoo
Effect of season on luteal activity during the postpartum period of dairy cows in temperate areas.
This study was designed to compare the reproductive response to timed AI of lactating dairy cows with cystic ovarian follicles treated with GnRH or hCG to synchronize ovulation. The effectiveness of treatment during the warm or cool period of the year was also compared. Cows were given 12 μg GnRH-agonist i.m. on day 0 of the protocol, 15 mg PGF2α i.m. on day 7, and either GnRH-agonist (GPG treatment) or 3000 IU hCG i.m. (GPH treatment) on day 9, followed by timed AI. The cows were randomly chronologically assigned to GPG (n = 130) or GPH (n = 136) group. All cows were inseminated at fixed time 16-22 h after the end of treatment. During the warm period the pregnancy rate to first AI was 12% (7/60) and 21% (14/68) for the GPG and GPH groups, respectively, there being no significant differences between groups; the cumulative pregnancy rate was 22% (13/60) and 21% (14/68) for the GPG and GPH groups, respectively, again with no significant intergroup differences. During the cool period pregnancy rate to first AI was not different between groups: 29% (20/70) for GPG and 32% (22/68) for GPH, respectively; whereas the cumulative pregnancy rate was significantly higher (P < 0.05) for the GPH groups than for the GPG group: 56% (39/70) and 78% (53/68), respectively. These findings indicate that during the warm period, the pregnancy rates of the cystic cows were similar whether they received GPG or GPH treatment, during the cool period, there is a beneficial effect to use hCG at day 9 of the ovsynch protocol compared GnRH on cumulative pregnancy rat
Estrus responses after administering cloprostenol during the luteal phase of the oestrus cycle of gilts.
Effect of the administration of GnRH or hCG on time of ovulation and the onset of estrus-to-ovulation interval in sows in Thailand.
Abstract
The aim of the present study was to evaluate the control of ovulation by the administration of human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) at the onset of estrus. Thirty-three multiparous sows housed under tropical conditions and showing standing estrus within 5 days after weaning were included. The sows were allocated to three groups, spontaneous ovulation (control group, n = 10), induced ovulation using 750 IU hCG (hCG group, n = 10), and induced ovulation using 50 μg GnRH (GnRH group, n = 13). The hormones were given at the onset of estrus and the occurrence of ovulation was monitored every 6 h by transrectal ultrasonography. Data for weaning-to-estrus interval, onset of estrus-to-ovulation interval (EOI), and the length of estrus were recorded. All sows in the control and hCG groups ovulated, while 3 out of 13 sows treated with GnRH developed cystic ovaries (did not ovulate). Of those sows ovulating, the EOI of the hCG (40.2 ± 1.7 h) and GnRH (37.5 ± 3.3 h) groups were shorter than that of the control group (63.6 ± 9.6 h; P < 0.05). In conclusion, the administration of either hCG or GnRH at the onset of estrus can control time of ovulation but, at the dose employed, sows receiving GnRH may develop ovarian cysts
Going Beyond Counting First Authors in Author Co-citation Analysis
The 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
Fertility of swamp buffalo following the synchronization of ovulation by the sequential administration of GnRH and PGF(2)alpha combined with fixed-timed artificial insemination.
This study evaluated fertility in swamp buffalo after synchronization of ovulation combined with fixed time artificial insemination. At the start of the study, designated day 0, from a group of 98 female Thai swamp buffalo, 55 buffalo (heifers n° = 20 and cows n° = 35) were selected to be synchronized with GnRH (Day 0) followed by PGF 2alpha (Day 7) and a second treatment with GnRH (Day 9). All buffalo were inseminated at two fixed times 12 h and 24 h after the second injection of GnRH (Ovsynch+TAI group); a second group of 43 buffalo (heifers n° = 19 and cows n° = 24) were not treated and were artificially inseminated (AI) at natural estrus (AI group). Blood samples were taken 22 days after insemination to evaluate progesterone plasma levels. In the Ovsynch+TAI group, overall conception rate (CR; i.e. the number of cows with progesterone >4.0 ng/ml on day 22 after AI divided by the number of animals inseminated), was 38.1% and overall pregnancy rate (PR; i.e. the number of cows that were pregnant at day 50-60 after insemination divided by the number of animals inseminated), was 32.7%. In the AI group overall CR and PR was 34.9%.Within the Ovsynch+TAI group, CR and PR were reduced (P < 0.05) in heifers compared with cows (CR 15.0% vs. 51.4% for heifers and cows, respectively; PR 15.0% vs. 42.9% for heifers and cows, respectively). Within the AI group the efficacy of treatment was similar between heifers and cows (CR and PR 31.6% for heifers and 37.5% for cows).In conclusion, this study indicates that in swamp buffalo it is possible to synchronize ovulation and use timed artificial insemination with the Ovsynch+TAI protocol. © 2010 Elsevier Inc
Variations on the Author
“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
Appropriate Similarity Measures for Author Cocitation Analysis
We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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