Seasonal reproductive patterns and effectiveness as teasers (ram effect) of Corriedale and Milchschaf rams

2012 ◽  
Vol 52 (11) ◽  
pp. 1036 ◽  
Author(s):  
R. Ungerfeld
Keyword(s):  
Sexual Behaviour ◽  
Seasonal Changes ◽  
Minimum Distance ◽  
Seasonal Pattern ◽  
Seasonal Patterns ◽  
Reproductive Pattern ◽  
Reproductive Patterns ◽  
Scrotal Circumference ◽  
Semen Characteristics ◽  
Ram Effect

The first objective of this study was to compare the seasonal reproductive pattern of Corriedale and Milchschaf rams. Because seasonal patterns were similar, a second objective was to compare the effectiveness of rams from both breeds to induce oestrus in seasonally anoestrous Corriedale ewes using the ram effect. In the first experiment, the seasonal changes of bodyweight, scrotal circumference, testosterone concentrations, sexual behaviour towards oestrous ewes (ano-genital sniffing, lateral approaches, flehmen, mount attempts, mounts, and copulation), and semen characteristics (total spermatozoa in the ejaculate, mass motility, and percentage of alive and normal spermatozoa) were recorded during 13 months in five Corriedale and seven Milchschaf rams. All recorded variables changed through the year, with maximum reproductive patterns occurring in summer and autumn. Milchschaf rams were heavier than Corriedale rams, but no difference was observed in their reproductive patterns. Experiment 2 was performed during the non-breeding season with 169 Corriedale and Polwarth mulitparous ewes. All ewes were isolated from the rams so that they could not see, hear or smell them (minimum distance: 1000 m) from Day –40. They were primed over 8 days with an intravaginal sponge impregnated with 50 mg of medroxiprogesterone. Four Corriedale rams were introduced to 83 ewes, and four Milchschaf rams to the remaining 86 ewes at sponge withdrawal, and oestrus was recorded for 5 days. On Day 5, no ewe of the group bred with Milchschaf rams was marked. By contrast, 46 out of 83 (55.4%) of the ewes bred with Corriedale rams were marked (P < 0.0001). It was concluded that reproductive seasonal pattern of Corriedale and Milchschaf rams, including scrotal circumference, testosterone concentrations, sexual behaviour and semen characteristics, was similar. However, Corriedale rams were more effective than Milchschaf rams in inducing oestrus in anoestrus ewes (the ram effect).

Seasonal Reproduction in Musky Rat-kangaroos, Hypsiprymnodon moschatus: a Response to Changes in Resource Availability

1997 ◽  
Vol 24 (5) ◽  
pp. 561 ◽  
Author(s):  
Andrew J. Dennis ◽  
Helene Marsh
Keyword(s):  
Resource Availability ◽  
Seasonal Changes ◽  
Reproductive Output ◽  
Selective Pressure ◽  
Seasonal Pattern ◽  
Seasonal Reproduction ◽  
Reproductive Pattern ◽  
High Fecundity ◽  
Male And Female ◽  
Breeding Seasons

Musky rat-kangaroos had a seasonal reproductive pattern. Males underwent a dramatic testicular expansion in October and the testes remained enlarged until April, when they reduced in size again. Females carried 1–3 pouch young from around March until October; juveniles were suckled until late December. Two primary food resources, fruits and litter fauna, underwent regular seasonal changes in abundance. The availability of fruits fluctuated to a greater degree than did that of litter fauna, both within and between years, which probably constituted the main selective pressure for a seasonal pattern of reproduction and high fecundity relative to most other macropodoids. Variation in the availability of fruits between years correlated with changes in the reproductive output of both male and female musky rat-kangaroos during breeding seasons.

Seasonal Variation of Suicide in the City of São Paulo, Brazil, 1996–2010

Crisis ◽  
2014 ◽  
Vol 35 (1) ◽  
pp. 5-9 ◽  
Author(s):  
Daniel Hideki Bando ◽  
Fernando Madalena Volpe
Keyword(s):  
Seasonal Pattern ◽  
Total Sample ◽  
Sao Paulo ◽  
Seasonal Patterns ◽  
São Paulo ◽  
Health Statistics ◽  
Males And Females ◽  
June July ◽  
The City ◽  
Over Time

Background: In light of the few reports from intertropical latitudes and their conflicting results, we aimed to replicate and update the investigation of seasonal patterns of suicide occurrences in the city of São Paulo, Brazil. Methods: Data relating to male and female suicides were extracted from the Mortality Information Enhancement Program (PRO-AIM), the official health statistics of the municipality of São Paulo. Seasonality was assessed by studying distribution of suicides over time using cosinor analyses. Results: There were 6,916 registered suicides (76.7% men), with an average of 39.0 ± 7.0 observed suicides per month. For the total sample and for both sexes, cosinor analysis estimated a significant seasonal pattern. For the total sample and for males suicide peaked in November (late spring) with a trough in May–June (late autumn). For females, the estimated peak occurred in January, and the trough in June–July. Conclusions: A seasonal pattern of suicides was found for both males and females, peaking in spring/summer and dipping in fall/winter. The scarcity of reports from intertropical latitudes warrants promoting more studies in this area.

scholarly journals Seasonal pattern of hepatitis E virus prevalence in swine in two different geographical areas of China

2013 ◽  
Vol 141 (11) ◽  
pp. 2403-2409 ◽  
Author(s):  
Y. H. LU ◽  
H. Z. QIAN ◽  
A. Q. HU ◽  
X. QIN ◽  
Q. W. JIANG ◽  
...  
Keyword(s):  
Hepatitis E Virus ◽  
Seasonal Pattern ◽  
Eastern China ◽  
Geographical Area ◽  
Hepatitis E ◽  
Southwestern China ◽  
Seasonal Patterns ◽  
Virus Prevalence ◽  
Swine Hepatitis ◽  
A Minor

SUMMARYWe studied seasonal patterns of swine hepatitis E virus (HEV) infection in China. From 2008 to 2011, 4200 swine bile specimens were collected for the detection of HEV RNA. A total of 92/2400 (3·83%) specimens in eastern China and 47/1800 (2·61%) specimens in southwestern China were positive for HEV. Seasonal patterns differing by geographical area were suggested. In eastern China, the major peak of HEV RNA prevalence was during March–April, with a minor peak during September–October, and a dip during July–August. In southwestern China, the peak was during September–October and the dip during March–April. The majority of subtype 4a cases (63/82, 76·83%) were detected in the first half of the year, while the majority of subtype 4b cases (26/29, 89·66%) were concentrated in the second half of the year, suggesting that different subtypes contribute to different peaks. Our results indicate that the distribution of HEV subtypes is associated with seasonal patterns.

Seasonal variation in births in rural East Pakistan

1972 ◽  
Vol 4 (1) ◽  
pp. 107-116 ◽  
Author(s):  
John Stoeckel ◽  
A. K. M. Alauddin Choudhury
Keyword(s):  
Seasonal Variation ◽  
Social Factors ◽  
Seasonal Pattern ◽  
Seasonal Patterns ◽  
First Order ◽  
Monthly Temperature ◽  
Monthly Distribution ◽  
Number Of Births

SummaryAn analysis of the monthly distribution of births in two areas of Matlab Thana, East Pakistan, indicates that there is a seasonal variation in births different from what would be expected by chance. The highest proportion of births occur in the last three months of a year and the lowest proportion between May and July. Investigation into some of the environmental and social factors which might contribute to the seasonal pattern revealed the following: mean minimum monthly temperature 9 months before birth was inversely related to the number of births; all occupations had seasonal patterns different from what would be expected by chance and the business and mill-and-office occupations had distributions significantly different from each other; the distribution of births for all pregnancy orders was different from chance and the distribution for first order pregnancies was significantly different from those for third and fourth or higher orders.

Seasonal reproductive patterns and recommended sampling times for sentinel fish species used in environmental effects monitoring programs in Canada

2010 ◽  
Vol 18 (NA) ◽  
pp. 115-135 ◽  
Author(s):  
Timothy J. Barrett ◽  
Kelly R. Munkittrick
Keyword(s):  
Fish Species ◽  
Environmental Effects ◽  
Reproductive Strategy ◽  
Mining Industry ◽  
Pulp And Paper ◽  
Reproductive Pattern ◽  
Metal Mining ◽  
Reproductive Patterns ◽  
Sampling Times ◽  
Environmental Effects Monitoring

Canada’s environmental effects monitoring (EEM) program is currently in its fifth cycle of monitoring for the pulp and paper industry and second cycle of monitoring for the metal mining industry. More than 60 different sentinel fish species have been used in the EEM fish population surveys and reproductive impacts have been identified as an issue of concern in the pulp and paper program. A review of the literature was conducted to obtain details of the reproductive biology of each fish species that has been used in EEM studies in Canada. Using available data on seasonal changes in gonadosomatic indices, the seasonal reproductive patterns of Canadian fish species were divided into categories based on reproductive strategy and the timing of initiation of gonadal recrudescence. Recommended sampling times were developed for each reproductive pattern based on periods of temporal stability, minimum variability, and maximum value in gonadosomatic indices within a reproductive cycle. The reproductive strategy, spawning time, spawning temperature, and recommended sampling time were provided for the each sentinel fish species as well as life history characteristics including longevity, age and size at maturity, and mobility. Examination of the fish surveys using small bodied forage species from the EEM pulp and paper program revealed that approximately 72% of these studies were not conducted at the developed recommended sampling times and the magnitude of impacts may be underestimated by failing to sample at the recommended time.

scholarly journals Spatial and Seasonal Variations of Standardized Photosynthetic Parameters under Different Environmental Conditions for Young Planted Larix olgensis Henry Trees

Forests ◽  
2018 ◽  
Vol 9 (9) ◽  
pp. 522 ◽  
Author(s):  
Qiang Liu ◽  
Fengri Li
Keyword(s):  
Environmental Conditions ◽  
Seasonal Variations ◽  
Seasonal Pattern ◽  
Repeated Measurements ◽  
Seasonal Patterns ◽  
Photosynthetic Parameters ◽  
Relative Depth ◽  
Larix Olgensis ◽  
Vertical Variations ◽  
Larix Olgensis Henry

Understanding the spatial and seasonal variations in leaf physiology is critical for accurately modeling the carbon uptake, physiological processes and growth of entire canopies and stands. For a 17-year-old Larix olgensis Henry plantation, vertical whorl-by-whorl sampling and analyses of seasonally repeated measurements of major photosynthetic parameters were conducted, and the correlations between photosynthetic parameters and environmental conditions, leaf morphological traits and spatial position within the crown were analyzed. According to the correlations, the photosynthetic parameters were standardized based on the environmental conditions to avoid the influence of the changing environment on the patterns of spatial and seasonal variations of photosynthetic parameters. The results showed that the standardized light-saturated net photosynthetic rate (SPmax), standardized dark respiration (SRd) and standardized stomatal conductance under saturated light (Sgs-sat) were all negatively related to the relative depth into the crown (RDINC) throughout the growing season. However, their vertical patterns were different during the development of the phenological phase. In addition, different gradients of environmental conditions also influenced the values and the range of the vertical variation in photosynthesis. High temperature and low humidity usually resulted in smaller values and weaker vertical variations of SPmax and Sgs-sat, but larger values and more obvious vertical variations in SRd. SPmax and Sgs-sat usually exhibited a parabolic seasonal pattern in different vertical positions within the crown; however, SRd generally followed a concave pattern. These seasonal patterns were all weaker with increasing RDINC. Different environments also exhibited a significant influence on the seasonal patterns of photosynthesis. We suggested that standardization is necessary before analyzing spatial and seasonal variations. A single environmental condition could not represent the spatial and seasonal patterns under all gradients of the environment. Spatial and seasonal variations should be simultaneously analyzed because they are related to each other.

Abstract P164: Seasonal patterns of mortality from cardiovascular diseases in Panama.

Circulation ◽  
2012 ◽  
Vol 125 (suppl_10) ◽  
Author(s):  
Jorge A Motta ◽  
Carlos Gordon ◽  
Beatriz Gomez ◽  
Eva Castillo ◽  
Hugo Herrera-Ballesteros
Keyword(s):  
Seasonal Pattern ◽  
Activity Patterns ◽  
Seasonal Patterns ◽  
Seasonal Cycles ◽  
Population Activity ◽  
Diabetes Mortality ◽  
Weather Changes ◽  
External Causes ◽  
Cv Disease ◽  
Seasonal Index

Seasonal patterns of cardiovascular (CV) mortality have been reported in many regions of the world, but mostly in temperate zones. These cycles and seasonal patterns of mortality have been identified by looking at mortality rate series over extended periods of time and by filtering its stochastic components. The reasons for these variations have been attributed to multiple causes. Empirical observations by health care worker have suggested that in Panama there are seasonal changes of CV disease mortality but this phenomenon had not been studied. The speculation is that this may be related to variation in the incidence of respiratory diseases, weather changes or to population activity patterns associated with holidays. Our hypothesis for this study is that in Panama mortality related to CV disease has a seasonal pattern. We compiled from the National Registry of Mortality all deaths that occurred in the country from cardiovascular diseases (n=36,145) and diabetes (n=7,076) for the years 2001–2009. A monthly time series of mortality was calculated and its components were decomposed utilizing moving averages. Elements, like cycle, seasonal occurrence and stochastic components, were separated. We also developed a seasonal index of mortality for these diseases. For the same years, we performed a similar analysis for all deaths attributed to cancer and external causes. Analysis of these mortality series revealed seasonal cycles for total cardiovascular mortality and diabetes mortality. Death from cancer and external causes also showed seasonal cycles. CV mortality and diabetes mortality peaked at the beginning of the third trimester of the year and were lowest during the first trimester. For the month of July, the CV mortality seasonal index showed a score of 108, and an average number of CV deaths of 364. The lowest seasonal index score for CV mortality was 87 in February, with an average number of CV deaths of 296. The cycles observed for cancer and deaths from external causes did not match the cycles observed for CV diseases and diabetes. We conclude that there is a seasonal pattern of CV mortality in Panama. The drivers of these cyclical changes of CV mortality have not yet been identified, but we are evaluating the relationship of acute respiratory illnesses, population activity patterns and weather changes to these seasonal mortality variations.

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