scholarly journals Efecto de la duración de cópula en la respuesta ovulatoria y tasa de preñez en alpacas

2021 ◽  
Vol 23 (4) ◽  
pp. 229-235
Author(s):  
Madeley Gladys Hilasaca Mamani ◽  
◽  
Jesús Martín Urviola Sánchez ◽  
Francisco Halley Rodríguez Huanca ◽  
Víctor Raúl Leyva Vallejos ◽  
...  
Keyword(s):  
Correspondence Analysis ◽  
Pregnancy Rates ◽  
Ovulation Rate ◽  
Copulation Duration ◽  
Mating Duration ◽  
Adult Females ◽  
The Difference ◽  
Positive Effect ◽  
In Pregnancy

An experiment was carried out at the Experimental Center La Raya-Universidad Nacional del Altiplano Puno, to determine the effect of copulation duration on ovulation and pregnancy in alpacas. 47 adult females were used (postpartum time ≥ 20 days and presence of a follicle ≥ 7 mm) distributed in three groups, according to copulation time: 20, 35 and 50 min, for G1 (n = 15), G2 (n = 16) and G3 (n = 16), respectively. For the mating, 6 reproducers of proven fertility were used, interrupting the copulation at the established time. Ovulation and pregnancy rates were evaluated on days 7 and 30 post service respectively (by ultrasound and receptivity of the female), the data were analyzed using X2 and simple correspondence. Both the ovulation rate (G1: 73.33%, G2: 81.25% and G3: 81.25%); and pregnancy (G1: 53.33%, G2: 81.25% and G3: 75%) were not different (P> 0.05). Pregnancy rates between G1 and G2 tended to be different (P <0.10), consistent with the simple correspondence analysis. Despite there being no differences in ovulation and pregnancy rates, there was a higher percentage trend in G2 and G3, suggesting that the longer duration of mating would have some positive effect on them, according to the simple correspondence analysis, and the trend of low significance (P <0.10) in favor of pregnancy in G2 compared to G1. In conclusion, there were no significant differences in the effect of copulation duration on ovulation; however, there was a 90% trend for the difference between mating duration of 35 minutes versus 20 minutes (in pregnancy).

Artificial insemination of farmed red deer (Cervus elaphus)

1990 ◽  
Vol 51 (3) ◽  
pp. 613-621 ◽  
Author(s):  
P. F. Fennessy ◽  
C. G. Mackintosh ◽  
G. H. Shackell
Keyword(s):  
Pregnancy Rate ◽  
Cervus Elaphus ◽  
Artificial Insemination ◽  
Red Deer ◽  
Pregnancy Rates ◽  
Progesterone Treatment ◽  
Serum Gonadotropin ◽  
The Difference ◽  
Fixed Times ◽  
In Pregnancy

ABSTRACTSix experiments involving the artificial insemination (AI) of a total of 300 female red deer (hinds) with frozen-thawed red deer semen (collected by electro-ejaculation) were conducted over 3 years. Insemination took place at fixed times following various oestrous synchronization procedures using progesterone withdrawal and treatment with pregnant mare's serum gonadotropin (PMSG). In the 1st year, the experiments evaluated basic AI techniques in which pregnancy rates were 45% in 20 hinds receiving two inseminations per vaginam (PV) and 56% in 27 hinds inseminated by the laparoscopic intrauterine method (IU). In the 2nd year, the experiments involved comparisons of the progesterone regime, one or two PV inseminations, and the timing of a single PV insemination. There was no effect of replacement of the progesterone device after 9 days and withdrawal 3 days later compared with the use of one device for the whole period in two experiments. The pregnancy rate for a double PV insemination was significantly higher than for a single PV insemination (58 and 34%; P < 0·05) and there was also a small effect of timing of insemination relative to the synchronization treatment. In the 3rd year all hinds were inseminated by the IU method. The experiments involved a comparison of various times of AI following progesterone withdrawal and a comparison of the progesterone regime. The overall pregnancy rate for 63 hinds inseminated was 56% with no difference between three times of insemination (48, 52 and 55 h). In the second experiment, the difference in pregnancy rate between treatment with progesterone for 15 days and 12 days (44 and 72% for 18 hinds per group) was not significant, but the interaction between the length of progesterone treatment and insemination time was significant (P < 0·05), with the 12-day progesterone/55 h insemination giving a much higher pregnancy rate than the 15-day/55 h insemination (89 and 20% respectively). Although no experiments involved direct comparisons of the routes of insemination, overall pregnancy rates were 56% for IU, 53% for double PV and 35% for single PV inseminations.

Trends in Pregnancy Rates for the United States, 1976-97: An Update

2001 ◽  
Author(s):  
Stephanie J. Ventura ◽  
William D. Mosher ◽  
Sally C. Curtin ◽  
Joyce C. Abma ◽  
Stanley Henshaw
Keyword(s):  
United States ◽  
The United States ◽  
Pregnancy Rates ◽  
In Pregnancy

P-Removal in Completely Mixed Systems

1985 ◽  
Vol 17 (11-12) ◽  
pp. 325-326 ◽  
Author(s):  
H J. G. W. Donker ◽  
P. Opic ◽  
H. P. de Vries
Keyword(s):  
Mixed System ◽  
Domestic Waste ◽  
Recirculation Flow ◽  
Start Up ◽  
Significant Difference ◽  
Aerobic Reactor ◽  
The Difference ◽  
Positive Effect ◽  
Mixed Systems ◽  
P Removal

Ca. 60 % of the Dutch activated sludge plants consist of completely mixed systems, experiments have been carried out in completely mixed pilot plants to study the biological P-removal. The research was carried out in two pilot plants. The pilot plants consisted of: anaerobic reactor, anoxic reactor, aerobic reactor and a clarifier. All the reactors were completely mixed. Both plants were fed with settled domestic waste water at a sludge loading of 400 and 250 g COD/kg sludge.day respectively. The results are given below:sludge loading (g COD/kg sludge.day)400400250ratio Anaerobic : Anoxic : Aerobic1: 1:2,71:1:4,11:1:2,7P-removal (%)802875N-removal (%)505065COD-removal (%)858585 It has been shown that there is no significant difference between the results at the two different sludge loadings. Remarkable is the difference between the ratio 1:1:2,7 in combination with the internal recirculation flow anoxic-anaerobic of 160 % and the ratio 1:1:4,1 with a recirculation flow of 30 %. During the start-up at a sludge loading of 250 g COD/kg sludge.day and an internal recirculation flow of 30 %, bulking sludge developed almost immediately. The Premoval was completely disturbed. Increasing the internal recirculation flow to 160% had a positive effect on settling properties and P-removal. This investigation has pointed out that a completely mixed system is suitable for biological P-removal, without negatively affecting the nitrification. Important factors in the process are the ratio anaerobic:anoxic:aerobic and the recirculation flows.

DIE AUSSCHEIDUNG VON TESTOSTERON UND EPITESTOSTERON BEI FRAUEN AM ENDE DER SCHWANGERSCHAFT

1969 ◽  
Vol 60 (4) ◽  
pp. 579-585
Author(s):  
K. Schollberg ◽  
E. Seiler ◽  
J. Holtorff
Keyword(s):  
Urinary Excretion ◽  
Late Pregnancy ◽  
Mean Values ◽  
Pregnant Females ◽  
Female Foetus ◽  
The Mean ◽  
The Difference ◽  
Normal Women ◽  
In Pregnancy

ABSTRACT The urinary excretion of testosterone and epitestosterone by women in late pregnancy has been studied. The mean values of 22 normal women in pregnancy mens X are 12.9 ± 9.2 μg/24 h in the case of testosterone and 16.1 ± 16.2 μg/24 h in the case of epitestosterone. Both values do not differ significantly from those of non-pregnant females. The excretion values of mothers bearing a male foetus (17.3 ± 8.9 μg/24 h) are higher than those of mothers with a female foetus (6.4 ± 4.8 μg/24 h). The difference is statistically significant with P = 0.01.

The effect of exposure to conspecifics on restlessness in the parasitoid wasp Nasonia vitripennis (Hymenoptera: Pteromalidae)

2007 ◽  
Vol 139 (5) ◽  
pp. 678-684 ◽  
Author(s):  
B.H. King
Keyword(s):  
Habitat Quality ◽  
Parasitoid Wasp ◽  
Poor Quality ◽  
The Other ◽  
Dispersal Ability ◽  
Nasonia Vitripennis ◽  
Adult Females ◽  
Selection For ◽  
The Difference ◽  
Abundance And Distribution

AbstractWhen habitat quality is variable, there should be strong selection for the ability to detect and respond to the variation. Adult females of the parasitoid wasp Nasonia vitripennis (Walker) are known to increase their restlessness (the proportion of time in locomotion) both during and after exposure to a poor quality host. Doing so provides a mechanism for leaving a poor host and potentially finding a better host. This study examined whether restlessness also changes in response to competition as indicated by the presence of adult conspecifics. Both restlessness and the probability of dispersing across an inhospitable environment were greater when a female was with another female than when she was alone. However, restlessness did not remain elevated after the other female was removed. In contrast with females, restlessness of males did not increase either during or after exposure to other males, and the probability of dispersing across an inhospitable environment was unaffected by the presence of another male. The difference between females and males may be related to differences in dispersal ability and in the abundance and distribution of hosts versus mates.

scholarly journals LA INSERCIÓN COMERCIAL DE CHINA EN LATINOAMÉRICA

2019 ◽  
Vol 78 (310) ◽  
pp. 137
Author(s):  
Jorge Alberto López Arévalo ◽  
Óscar Rodil Marzábal
Keyword(s):  
Costa Rica ◽  
Free Trade ◽  
Fixed Effects ◽  
Bilateral Trade ◽  
Free Trade Agreements ◽  
Trade Agreements ◽  
Trade Integration ◽  
Negative Effect ◽  
The Difference ◽  
Positive Effect

<p>Este trabajo estudia los intercambios bilaterales de China con México, Chile, Costa Rica y Perú desde la óptica del comercio intraindustrial durante 1995-2017. En particular, se analizan las diferencias en el patrón de inserción intraindustrial en un contexto marcado por la existencia (Chile, Costa Rica y Perú) o no (México) de acuerdos de libre comercio con China. El estudio se completa con un análisis econométrico (efectos fijos) de los determinantes del comercio intraindustrial. Los resultados muestran una inserción de bajo perfil intraindustrial, con la excepción de algunas partidas específicas relativas a productos eléctricos y de la industria automotriz. Por otro lado, se confirma el efecto positivo del tamaño de la economía, de la inversión extranjera directa y de la diferenciación de producto, así como negativo de la diferencia en el nivel de ingreso; mientras que existe una indefinición en el papel de los acuerdos de libre comercio con China.<br /><br /></p><p>THE TRADE INTEGRATION OF CHINA IN LATIN AMERICA</p><p> </p><p><strong>ABSTRACT</strong><br />This paper studies China’s bilateral trade with Mexico, Chile, Costa Rica and Peru from the perspective of intra-industrial trade during 1995-2017. In particular, the differences in the pattern of intra-industrial insertion are analyzed in a context characterized by the existence (Chile, Costa Rica and Peru) or not (Mexico) of free trade agreements with China. An econometric analysis (fixed effects) of the determinants of intra-industrial trade completes the study. The results show a low intra-industrial profile, except for some specific items related to electrical products and the automotive industry. The positive effect of the size of the economy, foreign direct investment and product differentiation is also confirmed, as well as the negative effect of the difference in income level. However, there is an undefined role for free trade agreements with China.</p>

scholarly journals Multimedia-Aided Instruction in Teaching Grade Four Science and Health: Its Effect on Pupils’ Performance and Attitude Towards Multimedia Use in the Classroom

2013 ◽  
Vol 2 (1) ◽  
Author(s):  
Virlen O. Galope
Keyword(s):  
Professional Growth ◽  
Teaching And Learning ◽  
Pedagogical Issues ◽  
Gain Scores ◽  
Quasi Experimental ◽  
Integration Effect ◽  
The Difference ◽  
Teaching Learning ◽  
Positive Effect

This study is focused on the effects of multimedia aided instructions in Grade 4 Science and health pupils’ performance and attitude towards multimedia. Specifically this study sought to explore the multimedia aided instruction on the learning environment of the grade four pupils’ performance in science and health. Two intact classes in grade 4 were exposed to multimedia aided instructions. The difference in gain scores produced by integrating multimedia in Science and Health 4 classes and those produced by conventional method of teaching was investigated in this quasi experimental research.  Results indicated that using the multimedia in the classes produced significant improvement in the performance of the pupils in Science and Health, but not in the other, which is congruent with most other results for this strategy of teaching found in the literature. Follow-up survey of attitudes of 86 pupils towards the use of multimedia in the classroom provided additional evidence for its positive effect in the teaching learning process. The pupils’ attitudes towards their class were positive about the potential for multimedia and enthusiastic about what this would mean in learning Science and Health. Utilizing multimedia seemed to affect the teachers’ personal and professional growth. Teachers expect to develop their technological skills and knowledge to use multimedia in their classrooms. Pedagogical issues challenge the teachers’ approaches in the teaching and learning. Keywords - Multimedia Integration, Effect on Pupils Performance, Attitude of Pupils towards Multimedia in the Classroom, quasi-experimental design, Philippines

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