Diet and breeding of the rufous spiny bandicoot Echymipera rufescens australis, Iron Range, Cape York Peninsula

2007 ◽  
Vol 29 (2) ◽  
pp. 169 ◽  
Author(s):  
D.I. Shevill ◽  
C.N. Johnson
Keyword(s):  
Breeding Season ◽  
Litter Size ◽  
Reproductive Rate ◽  
High Fecundity ◽  
Iron Range ◽  
Seed Disperser ◽  
Faecal Analysis ◽  
Live Trapping ◽  
Cape York ◽  
Trapping Grid

A population of the rufous spiny bandicoot Echymipera rufescens australis was studied for 14 months by live-trapping, and diets were determined by faecal analysis. The population had a high density (approximately 48 individuals on a trapping grid of 2.25 ha). A wide variety of foods were eaten, but fruits and seeds contributed the largest proportion of material to faeces, followed by invertebrates, fungi and dicot plants. Echymipera rufescens may potentially be a significant seed disperser for some plants, such as Pandanus zea. There was a short breeding season, with births occurring between December and March. Females produced one or two litters per year. Mean litter size was just under three, and litter size increased with the mother?s mass. Females produced a mean of 4.9 young per year. We conclude that although E. rufescens is a ?typical? bandicoot in that it is omnivorous and has high fecundity, it is more frugivorous and has a somewhat lower reproductive rate than other Australian bandicoots.

Breeding by Peromyscus in seasonal environments

1979 ◽  
Vol 57 (4) ◽  
pp. 719-727 ◽  
Author(s):  
John S. Millar ◽  
F. B. Wille ◽  
Stuart L. Iverson
Keyword(s):  
Breeding Season ◽  
Litter Size ◽  
Sexual Maturity ◽  
Peromyscus Maniculatus ◽  
Peromyscus Leucopus ◽  
Reproductive Rate ◽  
Reproductive Characteristics ◽  
Breeding Seasons

Reproductive characteristics of Peromyscus maniculatus in Manitoba and Peromyscus leucopus in Ontario were compared in order to determine the extent to which breeding compensates for relatively short breeding seasons. Peromyscus maniculatus had a shorter breeding season than P. leucopus, but frequency of litters, litter size, and age of females at sexual maturity were the same for both species. A comparison of breeding characteristics among Peromyscus from different geographic areas indicated that basic reproductive characteristics do not vary in relation to length of the breeding season.In general, we have no evidence that the basic reproductive characteristics of Peromyscus vary in relation to length of the breeding season. Peromyscus with short breeding seasons, on average, must have a lower annual reproductive rate than Peromyscus with long breeding seasons.

A population study of small rodents in a dry sub-humid grassland in Kenya

1985 ◽  
Vol 1 (3) ◽  
pp. 217-224 ◽  
Author(s):  
G. H. G. Martin
Keyword(s):  
Population Study ◽  
Annual Production ◽  
Small Rodents ◽  
Numerous Species ◽  
Tropical Grassland ◽  
Live Trapping ◽  
Mus Minutoides ◽  
Turn Over ◽  
Rodent Populations ◽  
Trapping Grid

ABSTRACTEstimates were made of rodent longevity, population biomass and production in a dry sub-humid grassland area in Kenya, The results were based on a live-trapping study made over a 27-month period. During this time fourteen species of rodents and four species of insectivores were recorded from the area of the trapping grid. The most numerous species were Praomys natalensis, Mus triton, Mus minutoides and Lemniscomys striatus.Breeding took place in both wet seasons, coinciding with peaks in rodent populations. Densities ranged from 6.6 ha-1 to 52.4 ha-1, and estimates of net annual production varied from 5485 g ha-1 year-1 to 7221 g ha-1 year-1. Rodent populations appear to turn over every six to nine months.The results are discussed in relation to studies in other tropical grassland areas of Africa.

The effect of melatonin treatment during the seasonal anoestrus on the superovulatory response and embryo production of high-prolificacy Rasa Aragonesa ewes before culling

2003 ◽  
Vol 2003 ◽  
pp. 82-82
Author(s):  
F. Forcada ◽  
J.A. Abecia ◽  
J.A. Valares
Keyword(s):  
Embryonic Development ◽  
Breeding Season ◽  
Litter Size ◽  
Direct Effect ◽  
Ovulation Rate ◽  
Corpora Lutea ◽  
Melatonin Treatment ◽  
Embryo Production ◽  
Spring Equinox

The efficacy of melatonin implants inserted around the spring equinox to improve fertility and ovulation rate or litter size in Mediterranean ewes has been previously reported (Chemineau et al., 1996; Forcada et al., 2002a.), indicating the ability of the hormone to regulate the hypothalamic activity (Viguié et al., 1995). Moreover, a direct effect of melatonin on corpora lutea and embryonic development has been also reported (Wallace et al., 1988; Abecia et al., 2002). The use of prolific Rasa Aragonesa (RA) ewes (a Mediterranean breed) before culling as embryo donors has been previously tested in the breeding season (Forcada et al., 2002b.). The aim of this experiment was to improve embryo production during the seasonal anoestrus period in selected superovulated RA ewes at the end of their reproductive lives through the use of melatonin.

scholarly journals Effects of BMP15 and GDF9 on Ovine Oocytes in an In Vitro Maturation System

2021 ◽  
Author(s):  
◽  
Aanchal Singh
Keyword(s):  
Cell Death ◽  
Litter Size ◽  
In Vitro Maturation ◽  
Cumulus Cell ◽  
Oocyte Quality ◽  
Mature Oocyte ◽  
High Ratio ◽  
High Fecundity ◽  
Species Specific

<p>Oocyte developmental competency is the intrinsic measure of oocyte quality and the capacity for a mature oocyte to support the early stages of embryo development and implantation. Oocyte-secreted factors (OSFs), such as growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15), play a pivotal role in regulating the synchrony of various complex maturation events within the cumulus-oocyte complex (COC) through the induction of paracrine and endocrine signalling. These proteins act synergistically to influence the proliferation and differentiation of granulosa cells (GCs), cumulus cell (CC) expansion, promote survival, ovulation, the attainment of developmental competency and fertility. Species-specific ratios suggest that poly-ovulatory mammals have increased fecundity due to high ratios of GDF9:BMP15, which is directly reflected in their large litter size. Interestingly, it has also been found that higher ratios of GDF9:BMP15 also increased blastocyst rate in sheep implying that these embryos develop from oocytes that are more developmentally competent.  In this study, I investigated the hypothesis that supplementing a commercial in vitro maturation (IVM) system with a high ratio of GDF9:BMP15 would increase the developmental competency sheep oocytes; a species with low-moderate litter size. To test this hypothesis, ovine oocytes were matured in a biphasic IVM system containing GDF9 and BMP15 at three divergent ratios (1:6, 1:1, 6:1). The results herein show that the 6:1 ratio resulted in higher levels of reagent transfer to the ovine oocyte through gap junctions (GJs) after 24 hours of incubation. Similarly, it was also observed that at the higher ratio, glutathione (GSH) levels were higher at 7.5 hours of incubation. The high GDF9:BMP15 ratio also facilitated the increased consumption of pyruvate by the COC consistently throughout the culture period. Importantly, the high GDF9:BMP15 ratio showed higher expression of the gene that encodes GJ (CX43) at 24 hours relative to the control. It was also demonstrated through decreased apoptotic factor (BAX:BCL2) ratios, that the addition of OSFs, regardless of ratio, protected against cell death. In summary, this study provides novel results that support the notion that a high GDF9:BMP15 ratio improves oocyte quality by delaying the timing of meiotic resumption. This subsequently improves the transport of key metabolites and antioxidants to protect against oxidative stress and cell death and aid in the completion of maturation, ultimately resulting in the increased developmental competency observed in high fecundity poly-ovulatory species.</p>

scholarly journals Evaluasi Produktivitas Domba Ekor Gemuk Berdasar Reproductive Rate

2018 ◽  
Vol 20 (2) ◽  
pp. 64
Author(s):  
Sigit Prastowo
Keyword(s):  
Birth Weight ◽  
Litter Size ◽  
Reproductive Rate ◽  
Ovulation Rate ◽  
Variable Component

<p>Fat Tailed Sheep represent one of Indonesian livestock that having excellence of comparability with other ruminants livestock. The excellence is quickly adult, short of pregnant age, and has the nature of bearing twin, so if evaluated from development aspect will be very beneficial. Reproductive Rate (RR) is a mount of reproduction ability from a group of ewes. Reproductive Rate defined as amount of weaned lamb by ewe every year. Variable/component related to RR are litter size, lamb mortalities before weaning and lambing interval.</p><p>Litter size is general influenced by difference of breeds, age and sufficiency of nutrition. Litter size is peculiarly influenced by ovulation rate that determined by breed, age, nutrition and parity. Lamb age, litter size, birth weight, season, nutrition and parity are influenced lamb mortalities before weaning. Lambing interval determined by nutrition factor and management, which is matting pattern and lamb weaning.</p>

Distribution, abundance and demography of green pythons (Morelia viridis) in Cape York Peninsula, Australia

2011 ◽  
Vol 59 (3) ◽  
pp. 145 ◽  
Author(s):  
Daniel James Deans Natusch ◽  
David Francis Stewart Natusch
Keyword(s):  
Conservation Management ◽  
Potential Range ◽  
Pet Trade ◽  
Policy Makers ◽  
Population Demographics ◽  
River Catchment ◽  
Iron Range ◽  
Ecological Attributes ◽  
Cape York ◽  
Effective Conservation

The green python (Morelia viridis) is an iconic snake species highly sought after in the pet trade and is the target of illegal collection. Despite their popularity, some important ecological attributes of green pythons remain unknown, making their effective conservation management difficult. Detection-only surveys were conducted throughout the potential range of the green python in Australia, and intensive mark–recapture surveys were conducted in the areas where there have been previous records. In total, 298 green pythons were located in the Iron, McIlwraith and Kawadji–Ngaachi ranges of Cape York, distributed over an estimated area of 2289 km2, where they frequented rainforest habitats and adjacent vine thickets. They were not found in the Lockerbie Scrub or Jardine River Catchment, despite anecdotal records. Green python density was estimated to be 540 km–2 in the Iron Range and 200 km–2 in the McIlwraith Range, where the percentages of adults captured were 56% and 83%, respectively. The differences between abundance and population demographics in the Iron and McIlwraith ranges may be due to differences in prey abundance and the impacts of collection. The results of this study provide baseline data to conservation managers and policy makers for the future conservation management of this species in Australia.

Calving performance and calf survival in a twin-calving beef herd

1990 ◽  
Vol 1990 ◽  
pp. 1-1
Author(s):  
M.G. Diskin ◽  
T.G. McEvoy ◽  
J.M. Sreenan
Keyword(s):  
Litter Size ◽  
Survival Rates ◽  
Reproductive Rate ◽  
Beef Production ◽  
Total Cost ◽  
Calf Survival ◽  
Beef Herd ◽  
Low Efficiency ◽  
High Level ◽  
Calving Performance

In suckler beef production it is estimated that 55% of the total cost is required to maintain and replace the breeding females while only 1095 of total feed energy intake is stored in the tissue of the calves and cows. The low reproductive rate of the cow is primarily responsible for this low efficiency. Even in a well managed herd, weaning rate Is about 0.95 calves per cow per annum or less. It Is frequently hypothesised that increasing litter size by inducing twin calving would increase output, biological and economic efficiency provided few extra Inputs were required. Although twinning may increase the efficiency of beef production, spontaneous twin-calving is frequently associated with an Increased incidence of calving problems, poor calf survival, retained placentae and longer rebreeding intervals. Such problems related to twin-calving cannot be studied unless the frequency of twinning is increased above the levels that occur spontaneously. Embryo transfer can be used to Increase the frequency of twin calving thus allowing a better assessment of the potential to Increase output. A suckler herd, with a high level of twinning, was established to determine the effects of litter size on calving performance and calf survival rates.

scholarly journals Association of Polymorphisms in Candidate Genes with the Litter Size in Two Sheep Breeds

Animals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 958 ◽  
Author(s):  
Yuan ◽  
Zhang ◽  
Li ◽  
Wang ◽  
Li ◽  
...  
Keyword(s):  
Candidate Genes ◽  
Genetic Markers ◽  
Litter Size ◽  
Nucleotide Polymorphisms ◽  
Female Reproduction ◽  
Dna Pooling ◽  
High Fecundity ◽  
Sheep Breeds ◽  
Hu Sheep ◽  
Six Genes

Hu sheep and Small-tailed Han sheep are the most widely raised and most famous maternal sheep breeds in China, which are known for precocious puberty, perennial oestrus and high fecundity (1–6 lambs each parity). Therefore, it is crucial to increase litter size of these two breeds for intensive sheep industry. The objective of this study was to identify potential genetic markers linked with sheep litter size located at ten genes. This study collected blood sample of 537 Hu sheep and 420 Small-tailed Han sheep with litter size of first parity. The average litter sizes in Hu sheep and Small-tailed Han sheep were 2.21 and 1.93. DNA-pooling sequencing method was used for detecting the potential single nucleotide polymorphisms (SNPs) in ten genes related to follicle development and female reproduction. SNPscan® was used for individually genotyping. As a result, a total of 78 putative SNPs in nine out of ten candidate genes (except NOG) were identified. In total, 50 SNPs were successfully genotyped in Hu sheep and Small-tailed Han sheep. After quality control, a total of 42 SNPs in Hu sheep and 44 SNPs in Small-tailed Han sheep were finally used for further analysis. Association analysis revealed that nine SNPs within six genes (KIT: g.70199073A>G, KITLG: g.124520653G>C, ADAMTS1: g.127753565T>C, ADAMTS1: g.127754640G>T, NCOA1: g.31928165C>T, NCOA1: g.32140565G>A, LIFR: g.35862868C>T, LIFR: g.35862947G>T and NGF: g.91795933T>C) were significantly associated with litter size in Hu sheep or Small-tailed Han sheep. A combined haplotypes analysis of the two loci (LIFR: g.35862868C>T and LIFR: g.35862947G>T) revealed that H2H3 (CTTT) combined haplotypes had the largest litter size than the rest combined haplotypes and more than those with either mutation alone in Small-tailed Han sheep. Taken together, our study suggests that nine significant SNPs in six genes can be served as useful genetic markers for MAS in sheep.

Reproductive changes in a cyclic population of snowshoe hares

2001 ◽  
Vol 79 (11) ◽  
pp. 2101-2108 ◽  
Author(s):  
Carol I Stefan ◽  
Charles J Krebs
Keyword(s):  
Pregnancy Rate ◽  
Breeding Season ◽  
Litter Size ◽  
Reproductive Output ◽  
Yukon Territory ◽  
The Body ◽  
Decline Phase ◽  
Snowshoe Hares ◽  
Early Increase ◽  
Changes In Pregnancy

Reproductive output was estimated for a cyclic population of snowshoe hares (Lepus americanus) in the Kluane Lake region of the southwest Yukon Territory. Data collected by five researchers were collated over 8 years (1989–1996). Pregnant hares were captured and held in cages until they gave birth so that reproductive characteristics could be measured. Pregnancy rate, litter size, and neonate size fluctuated significantly throughout the cycle, changes occurring about 2 years before corresponding changes in density. Pregnancy rates were nearly 100% early in the breeding season, but declined up to 20% in the last gestation periods of the year. The number of litters produced in a breeding season varied between two (decline phase) and four (low, early increase phase). Litter size varied among years as well as among litters within a year, larger litters being born later in the breeding season. The body mass and size of newborn hares varied by 5–33% among years. The combined changes in pregnancy rate and litter size resulted in a cyclic change in total reproductive output ranging from a low of 6.9 young per female during the decline phase to a maximum of 18.9 during the second year of the low and early increase phases.

scholarly journals Influence of birth weight and litter size on lamb survival in high fecundity Booroola-Merino crossbred flocks

1985 ◽  
Vol 28 (1) ◽  
pp. 31-38 ◽  
Author(s):  
G. N. Hinch ◽  
S. F. Crosbie ◽  
R. W. Kelly ◽  
J. L. Owens ◽  
G. H. Davis
Keyword(s):  
Birth Weight ◽  
Litter Size ◽  
High Fecundity ◽  
Lamb Survival
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