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1. Age and growth of the Cape knifejaw Oplegnathus conwayi, an endemic South African teleost

Author:
RM Foster; A-R Childs; BQ Mann; WM Potts
Source:
African zoology 2022 v.57 no.1 pp. 1-11
ISSN:
2224-073X
Subject:
sex ratio,   etc   ; Oplegnathus; females; growth curves; males; population growth; zoology; South Africa;     Show all 8 Subjects
Abstract:
... The South African spearfishery targets a variety of data-deficient species, which are consequently poorly managed. This study aimed to describe the age and growth of one of these species, the Cape knifejaw, Oplegnathus conwayi, which is endemic to the southern and eastern coasts of South Africa. Monthly biological samples were collected through research spearfishing (n = 170) and augmented by recr ...
DOI:
10.1080/15627020.2022.2035254

2. Effect of parent flock age on hatching, growth rate, and features of both sexes goose carcasses

Author:
Joanna Kucharska-Gaca; Marek Adamski; Jakub Biesek
Source:
Poultry science 2022 pp. 101920
ISSN:
0032-5791
Subject:
sex ratio,   etc   ; abdominal fat; body weight; dissection; flocks; muscles; oats; slaughter; waterfowl;     Show all 9 Subjects
Abstract:
... The study aimed to assess the hatchability of goslings from parent flocks of geese in 4 laying seasons and to analyze the growth, carcass, and muscles characteristics. The hatching eggs from the White Kołuda geese from the 1st to 4th laying season were incubated by the waterfowl hatching technology. Hatchability rates were calculated. 40 goslings were selected from each group. The geese were reare ...
DOI:
10.1016/j.psj.2022.101920

3. Rare occurrences of polygyny in the monogamous Florida Scrub-Jay (Aphelocoma coerulescens): Synthesis of 97 combined years of population monitoring across 3 populations

Author:
Rebecca L. Windsor; Angela Tringali; Michelle Dent; Reed Bowman
Source:
Wilson journal of ornithology 2022 v.133 no.3 pp. 484-490
ISSN:
1559-4491
Subject:
sex ratio,   etc   ; Aphelocoma coerulescens; females; landscapes; monogamy; ornithology; polygyny; reproductive performance; wildland;     Show all 9 Subjects
Abstract:
... Polygamy is common in many taxa, particularly birds. Several hypotheses support evolutionary or ecological explanations for the presence of polygamous mating systems, but these may not explain rare occurrences of polygamy in predominantly monogamous systems. We identified 12 cases of polygyny in 3 populations of varying landscape structure (contiguous wildlands, fragmented wildlands, and suburban) ...
DOI:
10.1676/20-00070

4. Local male breeding density affects extra‐pair paternity in a south temperate population of grass wrens Cistothorus platensis

Author:
Ramiro S. Arrieta; Leonardo Campagna; Bettina Mahler; Irby Lovette; Paulo E. Llambías
Source:
Journal of avian biology 2022 v.2022 no.4 pp. e02887
ISSN:
0908-8857
Subject:
sex ratio,   etc   ; Cistothorus; adults; genotyping; grasses; males; nests; paternity; progeny; space and time;     Show all 10 Subjects
Abstract:
... Demographic factors can affect the frequency of extra‐pair paternity (EPP) in birds, as the distribution and availability of potential mates in both space and time influence the rate of encounters between females and males. Over three breeding seasons, we intensively studied the breeding system of a south temperate population of grass wrens Cistothorus platensis by genotyping 73 broods (319 nestli ...
DOI:
10.1111/jav.02887

5. Performance of Ferrolure+ pheromone in the red palm weevil, Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) management in date palm growing areas of Sindh, Pakistan

Author:
Mushtaq Hussain Soomro; Jan Muhammad Mari; Imtiaz Ahmed Nizamani; Arfan Ahmed Gilal
Source:
Journal of the Saudi Society of Agricultural Sciences 2022 v.21 no.2 pp. 114-124
ISSN:
1658-077X
Subject:
sex ratio,   etc   ; Phoenix dactylifera; Rhynchophorus ferrugineus; hibernation; relative humidity; temperature; Costa Rica; Pakistan;     Show all 8 Subjects
Abstract:
... Red palm weevil (RPW), Rhynchophorus ferrugineus (Coleoptera: Dryophthoridae) has caused huge losses to date palm in Sindh province, main producer of dates in Pakistan. Due to lack of knowledge and availability regarding aggregation pheromones, mainly pesticides are used for its management. Therefore, seasonal monitoring of RPW was conducted at five talukas of Khairpur (Khairpur, KIngri, Kot Diji) ...
DOI:
10.1016/j.jssas.2021.07.004

6. Pollinating fig wasps’ simple solutions to complex sex ratio problems: a review

Author:
Jaco M. Greeff; Finn Kjellberg
Source:
Frontiers in zoology 2022 v.19 no.1 pp. 3
ISSN:
1742-9994
Subject:
sex ratio,   etc   ; eggs; females; figs; males; mating competitiveness; mortality; natural selection; oviposition; wasps;     Show all 10 Subjects
Abstract:
... Local mate competition (LMC) favours female biased clutch sex ratios because it reduces competition between brothers and provides extra mating opportunities for sons. Fig wasps seem to fit LMC model assumptions and lay female-biased sex ratios as predicted. These female biased sex ratios increase fitness greatly. In line with predictions, their sex ratios become less female-biased as the number of ...
DOI:
10.1186/s12983-021-00447-4

7. Compensatory mechanisms during development contribute to overcome intraspecific competition in a dipteran solitary ectoparasitoid with larval active host seeking behaviour

Author:
José E. Crespo; Marcela K. Castelo
Source:
Ecological entomology 2022 v.47 no.2 pp. 221-233
ISSN:
0307-6946
Subject:
sex ratio,   etc   ; Asilidae; Cyclocephala; adults; courtship; entomology; flight; instars; intraspecific competition; larvae; probability; superparasitism;     Show all 12 Subjects
Abstract:
... 1. Superparasitism has been rendered many times as detrimental for fitness, although there are examples in which the competing winning larvae compensate for its development. Here, we studied if, in the host‐parasitoid system Cyclocephala signaticollis (Coleoptera: Scarabaeidae) – Mallophora ruficauda (Diptera: Asilidae), larvae have compensatory mechanisms during development to overcome competitio ...
DOI:
10.1111/een.13104

8. Distribution, Dominance Structure, Species Richness, and Diversity of Bats in Disturbed and Undisturbed Temperate Mountain Forests

Author:
Krzysztof Piksa; Tomasz Brzuskowski; Tomasz Zwijacz-Kozica
Source:
Forests 2022 v.13 no.1 pp. -
ISSN:
1999-4907
Subject:
sex ratio,   etc   ; Fagus; Myotis mystacinus; altitude; climate change; rain; species richness; summer; temperature; Poland;     Show all 10 Subjects
Abstract:
... The increase in mean annual temperature and reduction in summer rainfall from climate change seem to increase the frequency of natural and human-made disturbances to forest vegetation. This type of rapid vegetation change also significantly affects bat diversity. The aim of our study was to document differences in the ecological parameters of bat assemblages in different types of temperate mountai ...
DOI:
10.3390/f13010056

9. Population structure of the stone crab Xantho poressa (Olivi, 1792) in a human-restricted access area

Author:
Nebis A. Navarro-Ojeda; Jose A. Cuesta; Enrique González-Ortegón
Source:
Regional studies in marine science 2022 v.53 pp. 102375
ISSN:
2352-4855
Subject:
sex ratio,   etc   ; Lithodidae; adults; coasts; fauna; littoral zone; males; marine science; polygyny; population structure;     Show all 10 Subjects
Abstract:
... Some of the elements in the rocky intertidal zone, such as boulders, act as a refuge, mating, feeding and nursery area for marine fauna. In the present study, we analysed the population structure of the intertidal stone crab Xantho poressa in a human-restricted area, between March 2019 and February 2020, comprised of a rocky shore along the SW Atlantic Spanish coast. The study aims to provide info ...
DOI:
10.1016/j.rsma.2022.102375

10. Regional Population Structure of the European Eel at the Southern Limit of Its Distribution Revealed by Otolith Shape Signature

Author:
Ana Moura; Ester Dias; Rodrigo López; Carlos Antunes
Source:
Fishes 2022 v.7 no.3 pp. -
ISSN:
2410-3888
Subject:
sex ratio,   etc   ; Anguilla anguilla; basins; body condition; eel; estuaries; ontogeny; otoliths; population structure; rivers;     Show all 10 Subjects
Abstract:
... Given the European eel population’s marked decrease since the 1980s, it has become urgent to collect information describing its regional population structure to improve management plans. The Minho River (NW-Portugal, SW-Europe) is an important basin for the eel at the southern limit of its distribution, but the species is poorly described. Thus, we aimed to study the structure of the European eel ...
DOI:
10.3390/fishes7030135

11. Performance of tenera oil palm hybrids in cauvery delta region of India

Author:
M. Tamil Selvan; S. Sumitha; A. Nithya Devi; H.P. Maheswarappa; R.K. Mathur
Source:
Indian journal of horticulture 2022 v.79 no.1 pp. 76-80
ISSN:
0974-0112
Subject:
sex ratio,   etc   ; Elaeis guineensis; females; horticulture; hybrids; lipid content; males; mesocarp; raw fruit; seeds; India;     Show all 11 Subjects
Abstract:
... A study was carried out to find prospective tenera hybrids for cultivation in the Cauvery Delta region. The experiment was set up in a randomized block design with three replications involving ten cross combinations of tenera hybrids (NRCOp 11–20). The data of twelve years indicated that, palm height, stem girth and No. of leaves produced palm⁻¹ year⁻¹ revealed significant variations among the ten ...
DOI:
10.5958/0974-0112.2022.00012.3

12. Sex Ratio and Male Maturity for Shortfin Mako Shark in the Moroccan Central Atlantic Coast

Author:
Jihade Alahyene; Brahim Chiahou; Hammou El Habouz; Abdelbasset Ben-Bani
Source:
Croatian journal of fisheries 2022 v.80 no.2 pp. 67-75
ISSN:
1848-0586
Subject:
sex ratio,   etc   ; Isurus oxyrinchus; autumn; coasts; juveniles; males; sexual maturity; sharks; spring; traditional technology; winter;     Show all 11 Subjects
Abstract:
... The study on the reproductive biology of shortfin mako shark is carried out through the commercial catches from artisanal boats active on the Moroccan Central Atlantic coast and landed in Sidi Ifni Port, for the period between October 2017 and August 2019. A total of 1690 individuals were examined, including 846 females and 844 males. As a result, the overall sex ratio of shortfin mako sharks tend ...
DOI:
10.2478/cjf-2022-0007

13. Impact of native Wolbachia on reproductive fitness and bacterial pathogens in Aedes aegypti mosquitoes

Author:
Sivaraman Balaji; Solai Ramatchandirane Prabagaran
Source:
International journal of tropical insect science 2022 v.42 no.1 pp. 965-975
ISSN:
1742-7592
Subject:
sex ratio,   etc   ; Aedes aegypti; Wolbachia; disease transmission; embryonic mortality; fecundity; insects; longevity; reproductive fitness; vector control;     Show all 10 Subjects
Abstract:
... Wolbachia mediated vector control has received considerable attention globally due to its effects on reproductive fitness and ability to prevent disease transmission. However, most vector control programs involving artificial transinfections could be influenced by native Wolbachia strains, which needs investigation. In this line, the effect of naturally occurring Wolbachia strain wAegB on its host ...
DOI:
10.1007/s42690-021-00623-3

14. Sex ratio of Aphelenchoides besseyi within Oryza sativa seeds with relation to reproduction of rehydrated adult females

Author:
Katsumi Togashi; Shigeru Hoshino
Source:
Plant pathology 2022 v.71 no.5 pp. 1195-1204
ISSN:
0032-0862
Subject:
sex ratio,   etc   ; Aphelenchoides besseyi; Japan; Oryza sativa; adults; ectoparasites; females; plant pathology; probability; reproduction; rice; spermatheca;     Show all 12 Subjects
Abstract:
... The white‐tip nematode, Aphelenchoides besseyi, is a seedborne ectoparasite of rice, Oryza sativa. It enters dehydrated quiescence within maturing seeds. Soaking dry seeds in water causes the quiescent nematodes to revive and the rehydrated nematodes emerge from the seeds. Two field nematode populations in Japan exhibited female‐biased sex ratios of living and dead adults in seeds (the proportion ...
DOI:
10.1111/ppa.13543

15. Survie selon la variation de la dépense énergétique au repos (DER) avec deux formules de DER en l’absence de calorimétrie indirecte chez les patients atteints de sclérose latérale amyotrophique

Author:
P. Fayemendy; N. Calmel; H. Sourisseau; G. Lautrette; P.-M. Preux; P. Couratier; J.C. Desport; P. Jésus
Source:
Nutrition clinique et métabolisme 2021 v.35 no.1 pp. 52-53
ISSN:
0985-0562
Subject:
sex ratio,   etc   ; hazard ratio; nutrition;     Show all 3 Subjects
Abstract:
... The increased change in resting energy expenditure (RER) in ALS is a prognostic factor for survival mainly in patients with a change in DER >+20%. Measurement of DER by indirect calorimetry (IC) against predicted DER with formula (Harris and Benedict [HB] 1919, HB 1984 or Mifflin) is necessary to obtain the change in DER. However, IC is not available in many centers. The formula of Jesus et al. [1 ...
DOI:
10.1016/j.nupar.2021.01.068

16. Biometry, size structure and reproductive cycle of the sanded sea cucumbers Holothuria poli (Echinodermata, Holothuriidae) from the west Algerian coast

Author:
Karim Mezali; Zineb Lebouazda; Farah Slimane-Tamacha; Dina Lila Soualili
Source:
Invertebrate reproduction & development 2022 v.66 no.1 pp. 67-77
ISSN:
2157-0272
Subject:
sex ratio,   etc   ; Holothuria; allometry; biometry; body weight; coasts; databases; females; gonads; invertebrates; males; reproduction; sexual maturity; summer;     Show all 14 Subjects
Abstract:
... The aim of this work is to study the biometric and reproductive characteristics of a population of Holothuria poli from the west Algerian coast. The study was carried out on 256 individuals (33.25 ± 12.38 g wet weight and 196.44 ± 37.81 mm relaxed length) collected from Oran Bay between October 2016 and September 2017. All individuals showed negative allometric growth (b = 1.586) and the populatio ...
DOI:
10.1080/07924259.2022.2033331

17. Reproductive biology of the holothurian Parastichopus regalis in the Mediterranean Sea and its implications for fisheries management

Author:
M. Ramón; M.J. Amor; E. Galimany
Source:
Fisheries research 2022 v.247 pp. 106191
ISSN:
0165-7836
Subject:
sex ratio,   etc   ; Holothuria; autumn; ecology; evisceration; fisheries; fisheries management; gonads; reproduction; research; spring; summer; winter; Mediterranean Sea;     Show all 14 Subjects
Abstract:
... The sea cucumber Parastichopus regalis is a fished resource in the northwestern Mediterranean Sea but there are no studies about its reproductive biology. The aim of the present study is to characterize the reproductive ecology of P. regalis including its sex ratio, a description of the gonad and the reproductive cycle to help the implementation of a sustainable exploitation plan. A total of 1728 ...
DOI:
10.1016/j.fishres.2021.106191

18. The reproductive biology of Mystus mysticetus Robert, 1992 in the Mekong Delta, Vietnam

Author:
Lam Thi Thao Vo; Anh Ngoc Tran; Thu Quynh Phan; Quang Minh Dinh
Source:
Egyptian Journal of Aquatic Research (Online) 2022 pp. -
ISSN:
1687-4285
Subject:
sex ratio,   etc   ; Mystus; catfish; eggs; fecundity; females; freshwater; gonadosomatic index; oocytes; research; river deltas; wet season; Vietnam;     Show all 13 Subjects
Abstract:
... This investigation aims to study the reproductive traits, including sex ratio, spawning season and pattern, batch fecundity (F), and length at first maturity (Lₘ), of the commercial catfish Mystusmysticetus living in the freshwater of the Mekong and Chao Phraya basins. A collection of 596 individuals was caught using trawl nets from Cai Rang, Can Tho (CT) and Long Phu, Soc Trang (ST) from October ...
DOI:
10.1016/j.ejar.2022.05.002

19. Biology of Acerophagus texanus (Howard, 1898) (Hymenoptera: Encyrtidae), a parasitoid of Ferrisia virgata Cockerell (Hemiptera: Pseudococcidae)

Author:
Sergio A. Mejía-Ortíz; John S. Noyes; Francisco Infante; Juan Cisneros-Hernández; Alfredo Castillo-Vera
Source:
International journal of tropical insect science 2022 v.42 no.3 pp. 2523-2529
ISSN:
1742-7592
Subject:
sex ratio,   etc   ; Encyrtidae; Ferrisia virgata; adults; bees; eggs; endoparasitoids; fecundity; honey; instars; larvae; longevity; parasitism; progeny; rambutans; Mexico;     Show all 16 Subjects
Abstract:
... Acerophagus texanus (Howard) (Hymenoptera: Encyrtidae) is a primary endoparasitoid of Ferrisia virgata Cockerell (Hemiptera: Pseudococcidae). The parasitoid was described in 1898. It has been little studied and much of its biology remained unexplored. In the present investigation, several biological aspects of this species, such as the life cycle, fecundity, and longevity were studied under labora ...
DOI:
10.1007/s42690-022-00782-x

20. Effect of the timing of insemination (pre- or post-ovulatory) and type of semen (refrigerated or frozen) on the sex ratio of equine offspring

Author:
R Sanchez; C Herrera; M Witkowski
Source:
Journal of equine veterinary science 2022 v.113 pp. 103985
ISSN:
0737-0806
Subject:
sex ratio,   etc   ; data analysis; ecology; edema; endometrium; insemination; mares; maternal lineage; ovulation; progeny; refrigeration; semen; stallions; veterinary medicine;     Show all 14 Subjects
Abstract:
... The normal sex ratio of equine newborns is close to 1:1, with a slight increase of females over males, particularly when the mare is in poor physical condition (Cameron et al., Behavioral Ecology 1999 10(5):472-475). Many other factors like the age of the mare and stallion (Machado Santos et al., Theriogenology 2015 Oct 15;84(7):1238-45), maternal lineage, and uterine status of the mare (Kuhl et a ...
DOI:
10.1016/j.jevs.2022.103985