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  1. Sex ratio, gonad development and fecundity of Miyakella nepa (Crustacea, Stomatopoda) of Pantai Remis coastal waters of Malaysia
    Zamri Z, Arshad A, Amin SMN, Rahman MA, Al Khayat JA
    J Environ Biol, 2016 07;37(4 Spec No):677-83.
    PMID: 28779726
    The sex ratio, gonad development and fecundity of Miyakella nepa (Latreille, 1828), in the coastal waters of Pantai Remis, Perak, were investigated from February 2012 to January 2013. Sex identification was done by identifying stomatopod's genitalia organs, and the ovaries were dissected out and preserved for further analysis. Female stomatopods with mature or near spawning stages were used for fecundity estimation. A total of 951 specimens of M. nepa, with 565 females and 386 males were examined. Results showed a sex ratio of 1:1.46 (male:females). Maximum GSI was estimated to be 5.80, while lowest was 2.95. Sexual maturity for female M. nepa was observed at 100 mm total length. The mean fecundity of M. nepa was 425,657 (? 1,8701) eggs which was observed to increase with increased body length.
    Matched MeSH terms: Fertility/physiology*
  2. Fecundity, embryonic and ovarian development of blue swimming crab, Portunus pelagicus (Linnaeus, 1758) in coastal water of Johor, Malaysia
    Ikhwanuddin M, Azra MN, Siti-Aimuni H, Abol-Munafi AB
    Pak J Biol Sci, 2012 Aug 01;15(15):720-8.
    PMID: 24171257
    Blue swimming crab, Portunus pelagicus is widely study and research throughout the Indo-West Pacific, but little is known of its reproductive biology in Malaysia. The present study describes the fecundity, embryonic development and ovarian development stages of the P. pelagicus from Johor coastal water, Malaysia. Carapace width range of berried crabs sampled was from 9.64 to 13.32 cm, while the body weight range was from 75 to 235 g. The mean number of egg produced by females in different sizes ranged from 105443.333 +/- 35448.075 per eggs batch. Mean egg size during embryonic development at stage 1 was 0.307 +/- 0.037, while 0.386 +/- 0.039 and 0.396 +/- 0.033 for stage 2 and stage 3, respectively. Study showed that there was significant (p < 0.05) relationship between the number of eggs and carapace width/body weight. Mean diameter oocyte during ovarian development at stage 1 was 97.732 +/- 12.391 while for stage 2 was 149.516 +/- 23.287. Stage 3 showed increasingly of size with mean diameter was 158.506 +/- 27.616 and 181.013 +/- 24.339 for stage 4.
    Matched MeSH terms: Fertility/physiology
  3. Fulltext Biting rhythm and demographic attributes of Aedes albopictus (Skuse) females from different urbanized settings in Penang Island, Malaysia under uncontrolled laboratory conditions
    Muhammad NAF, Abu Kassim NF, Ab Majid AH, Abd Rahman A, Dieng H, Avicor SW
    PLoS One, 2020;15(11):e0241688.
    PMID: 33175896 DOI: 10.1371/journal.pone.0241688
    Urbanization could potentially modify Aedes albopictus' ecology by changing the dynamics of the species, and affecting their breeding sites due to environmental changes, and thus contribute to dengue outbreaks. Thus, this study was conducted to evaluate the biting rhythm, fecundity and longevity of adult female Ae. albopictus in relation to urbanization strata; urban, suburban and rural areas in Penang Island, Malaysia. The experiments were done in comparison to a laboratory strain. Twenty-four hours biting activity of all the mosquito strains showed a clear bimodal biting activity, with morning and evening twilight peaks. The interaction effect between biting time and mosquito strains was not significant. Meanwhile, differences in fecundity among mosquito strains were statistically significant (F(3,442) = 10.559, P < 0.05) with urban areas having higher mean number of eggs (mean = 107.69, standard error = 3.98) than suburban (mean = 94.48, standard error = 5.18), and rural areas (mean = 72.52, standard error = 3.87). Longevity of adult females were significantly higher (F(3,441) = 31.259, P < 0.05) for mosquito strains from urban areas compared to the other strains. These findings would provide crucial information for the planning of control programs in Malaysia, particularly Penang.
    Matched MeSH terms: Fertility/physiology
  4. The optimal number of heifer calves to be reared as dairy replacements
    Mohd Nor N, Steeneveld W, Mourits MC, Hogeveen H
    J Dairy Sci, 2015 Feb;98(2):861-71.
    PMID: 25497803 DOI: 10.3168/jds.2014-8329
    Dairy farmers often keep almost all their newborn heifer calves despite the high cost of rearing. By rearing all heifer calves, farmers have more security and retain flexibility to cope with the uncertainty in the availability of replacement heifers in time. This uncertainty is due to mortality or infertility during the rearing period and the variation in culling rate of lactating cows. The objective of this study is to provide insight in the economically optimal number of heifer calves to be reared as replacements. A herd-level stochastic simulation model was developed specific for this purpose with a herd of 100 dairy cows; the biological part of the model consisted of a dairy herd unit and rearing unit for replacement heifers. The dairy herd unit included variation in the number of culled dairy cows. The rearing unit incorporated variation in the number of heifers present in the herd by including uncertainty in mortality and variation in fertility. The dairy herd unit and rearing unit were linked by the number of replacement heifers and culled dairy cows. When not enough replacement heifers were available to replace culled dairy cows, the herd size was temporarily reduced, resulting in an additional cost for the empty slots. When the herd size reached 100 dairy cows, the available replacement heifers that were not needed were sold. It was assumed that no purchase of cows and calves occurred. The optimal percentage of 2-wk-old heifer calves to be retained was defined as the percentage of heifer calves that minimized the average net costs of rearing replacement heifers. In the default scenario, the optimal retention was 73% and the total net cost of rearing was estimated at €40,939 per herd per year. This total net cost was 6.5% lower than when all heifer calves were kept. An earlier first-calving age resulted in an optimal retention of 75%, and the net costs of rearing were €581 per herd per year lower than in the default scenario. For herds with a lower or higher culling rate of dairy cows (10 or 40% instead of 25% in the default scenario), it was optimal to retain 35 or 100% of the heifer calves per year. Herds that had a lower or higher cost of empty slots (€50 or €120 per month instead of €82 in the default scenario) had an optimal retention of 49 or 83% per year; the optimal retention percentage was dependent on farm and herd characteristics. For Dutch dairy farming conditions, it was not optimal to keep all heifer calves.
    Matched MeSH terms: Fertility/physiology
  5. Fulltext Father absence and reproduction-related outcomes in Malaysia, a transitional fertility population
    Sheppard P, Snopkowski K, Sear R
    Hum Nat, 2014 Jun;25(2):213-34.
    PMID: 24610662 DOI: 10.1007/s12110-014-9195-2
    Father absence is consistently associated with children's reproductive outcomes in industrialized countries. It has been suggested that father absence acts as a cue to particular environmental conditions that influence life history strategies. Much less is known, however, about the effects of father absence on such outcomes in lower-income countries. Using data from the 1988 Malaysian Family Life Survey (n = 567), we tested the effect of father absence on daughters' age at menarche, first marriage, and first birth; parity progression rates; and desired completed family size in Malaysia, a country undergoing an economic and fertility transition. Father absence during later childhood (ages 8 to 15), although not during earlier childhood, was associated with earlier progressions to first marriage and first birth, after controlling for other confounders. Father absence does not affect age at menarche, desired family size, or progression from first to second birth. The patterns found in this transitional population partly mirror those in developed societies, where father absence accelerates reproductive events. There is, however, a notable contrast between the acceleration in menarche for father-absent girls consistently found in developed societies and the lack of any association in our findings. The mechanisms through which father absence affects reproduction may differ in different ecological contexts. In lower-income contexts, direct paternal investment or influence may be of more importance in determining reproductive behavior than whether fathers act as a cue to environmental conditions.
    Matched MeSH terms: Fertility/physiology*
  6. Fulltext Indoor-breeding of Aedes albopictus in northern peninsular Malaysia and its potential epidemiological implications
    Dieng H, Saifur RG, Hassan AA, Salmah MR, Boots M, Satho T, et al.
    PLoS One, 2010;5(7):e11790.
    PMID: 20668543 DOI: 10.1371/journal.pone.0011790
    The mosquito Ae. albopictus is usually adapted to the peri-domestic environment and typically breeds outdoors. However, we observed its larvae in most containers within homes in northern peninsular Malaysia. To anticipate the epidemiological implications of this indoor-breeding, we assessed some fitness traits affecting vectorial capacity during colonization process. Specifically, we examined whether Ae. albopictus exhibits increased survival, gonotrophic activity and fecundity due to the potential increase in blood feeding opportunities.
    Matched MeSH terms: Fertility/physiology
  7. Sterile mosquitoes near take-off
    Cyranoski D
    Nature, 2008 May 22;453(7194):435.
    PMID: 18497781 DOI: 10.1038/453435a
    Matched MeSH terms: Fertility/physiology*
  8. Fulltext Mixed Mating System Are Regulated by Fecundity in Shorea curtisii (Dipterocarpaceae) as Revealed by Comparison under Different Pollen Limited Conditions
    Tani N, Tsumura Y, Fukasawa K, Kado T, Taguchi Y, Lee SL, et al.
    PLoS One, 2015;10(5):e0123445.
    PMID: 25938512 DOI: 10.1371/journal.pone.0123445
    The maintenance of mixed mating was studied in Shorea curtisii, a dominant and widely distributed dipterocarp species in Southeast Asia. Paternity and hierarchical Bayesian analyses were used to estimate the parameters of pollen dispersal kernel, male fecundity and self-pollen affinity. We hypothesized that partial self incompatibility and/or inbreeding depression reduce the number of selfed seeds if the mother trees receive sufficient pollen, whereas reproductive assurance increases the numbers of selfed seeds under low amounts of pollen. Comparison of estimated parameters of self-pollen affinity between high density undisturbed and low density selectively logged forests indicated that self-pollen was selectively excluded from mating in the former, probably due to partial self incompatibility or inbreeding depression until seed maturation. By estimating the self-pollen affinity of each mother tree in both forests, mother trees with higher amount of self-pollen indicated significance of self-pollen affinity with negative estimated value. The exclusion of self-fertilization and/or inbreeding depression during seed maturation occurred in the mother trees with large female fecundity, whereas reproductive assurance increased self-fertilization in the mother trees with lower female fecundity.
    Matched MeSH terms: Fertility/physiology*
  9. Fecundity, nymphal development and longevity of field-collected tropical bedbugs, Cimex hemipterus
    How YF, Lee CY
    Med Vet Entomol, 2010 Jun;24(2):108-16.
    PMID: 20202109 DOI: 10.1111/j.1365-2915.2010.00852.x
    This study examined the fecundity, oviposition, nymphal development and longevity of field-collected samples of the tropical bedbug, Cimex hemipterus (Fabricius) (Hemiptera: Cimicidae). Under environmental conditions of 26+/-2 degrees C, 70 +/- 5% relative humidity and a 12-h photoperiod, with bloodmeals provided by a human host, six strains of tropical bedbug had a fecundity of up to 50 eggs per lifetime, over 11-14 oviposition cycles. Increased feeding frequency improved fecundity. After feeding and mating, adult females normally took 2-3 days to produce a first batch of eggs. The oviposition period lasted 2-7 days before cessation of the oviposition cycle. The egg incubation period usually lasted 5-7 days before the emergence of first instars. The nymphs underwent five stadia (the first four of which each took 3-4 days, whereas the last took 4-5 days) before becoming adults at a sex ratio of 1 : 1. More than five bloodmeals were required by the nymphs to ensure a successful moult. Unmated adults lived significantly longer than mated adults (P < 0.05). Unmated females lived up to almost 7 months, but the longevity of mated males and females did not differ significantly (P > 0.05).
    Matched MeSH terms: Fertility/physiology
  10. Geographical differences in semen characteristics: Comparing semen parameters of infertile men of the United States and Iraq
    Palani A, Sengupta P, Agarwal A, Henkel R
    Andrologia, 2020 Apr;52(3):e13519.
    PMID: 32003032 DOI: 10.1111/and.13519
    The declining trend of male fecundity is a major global health and social concern. Among numerous other confounding factors, variations in male fertility parameters in different regions have repeatedly been suggested to be influenced by geographic locations. The impact of overall lifestyle, behavioural patterns, ethnicity, work stress and associated factors upon health differ greatly between developed and developing countries. These factors, individually or in combination, affect male reproductive functions ensuing the discrepancies in semen qualities in connection with geographic variations. However, reports comparing semen characteristics between developed and developing countries are sparse. The present study finds its novelty in presenting a comparison in semen parameters of infertile men in the United States (n = 76) that fairly represents the population of a highly developed region and Iraq (n = 102), the representative of male populations of a developing region. Samples were collected and analysed according to WHO (WHO laboratory manual for the examination and processing of human semen, WHO; 2010) criteria by means of the Mann-Whitney test. The US population demonstrated lower sperm concentration, total count, and total and progressive sperm motility with a higher seminal total antioxidant capacity (TAC) as compared to the Iraqi population. This report encourages further investigations concerning the confounding factors leading to such alterations in semen qualities between these two geographic areas.
    Matched MeSH terms: Fertility/physiology*
  11. Sperm parameters quality and reproductive effects of methanolic extract of Alchornea cordifolia leaves on senescent male rats
    Ngaha Njila MI, Massoma Lembè D, Koloko BL, Yong Meng G, Ebrahimi M, Awad EA, et al.
    Andrologia, 2019 Oct;51(9):e13359.
    PMID: 31353623 DOI: 10.1111/and.13359
    The effect of the methanolic extract of Alchornea cordifolia leaves on the fertility of senescent male rats was assessed in this study. 40 rats received daily distilled water, testosterone, 200 and 400 mg/kg of extract of Alchornea cordifolia. The reproductive organs weight, the gonadotropins, testosterone and cholesterol level, the sperm parameters, histology of the testes and epididymis were assessed. The weight of testes and prostate (400 mg/kg) significantly increased (p 
    Matched MeSH terms: Fertility/physiology
  12. Fulltext Changing domesticity of Aedes aegypti in northern peninsular Malaysia: reproductive consequences and potential epidemiological implications
    Saifur RG, Dieng H, Hassan AA, Salmah MR, Satho T, Miake F, et al.
    PLoS One, 2012;7(2):e30919.
    PMID: 22363516 DOI: 10.1371/journal.pone.0030919
    BACKGROUND: The domestic dengue vector Aedes aegypti mosquitoes breed in indoor containers. However, in northern peninsular Malaysia, they show equal preference for breeding in both indoor and outdoor habitats. To evaluate the epidemiological implications of this peridomestic adaptation, we examined whether Ae. aegypti exhibits decreased survival, gonotrophic activity, and fecundity due to lack of host availability and the changing breeding behavior.

    METHODOLOGY/PRINCIPAL FINDINGS: This yearlong field surveillance identified Ae. aegypti breeding in outdoor containers on an enormous scale. Through a sequence of experiments incorporating outdoors and indoors adapting as well as adapted populations, we observed that indoors provided better environment for the survival of Ae. aegypti and the observed death patterns could be explained on the basis of a difference in body size. The duration of gonotrophic period was much shorter in large-bodied females. Fecundity tended to be greater in indoor acclimated females. We also found increased tendency to multiple feeding in outdoors adapted females, which were smaller in size compared to their outdoors breeding counterparts.

    CONCLUSION/SIGNIFICANCE: The data presented here suggest that acclimatization of Ae. aegypti to the outdoor environment may not decrease its lifespan or gonotrophic activity but rather increase breeding opportunities (increased number of discarded containers outdoors), the rate of larval development, but small body sizes at emergence. Size is likely to be correlated with disease transmission. In general, small size in Aedes females will favor increased blood-feeding frequency resulting in higher population sizes and disease occurrence.

    Matched MeSH terms: Fertility/physiology
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