scholarly journals Dietary specialisation in a Critically Endangered pipefish revealed by faecal eDNA metabarcoding

2021 ◽  
Author(s):  
Ofentse K. Ntshudisane ◽  
Arsalan Emami-Khoyi ◽  
Gavin Gouws ◽  
Sven-Erick Weiss ◽  
Nicola C. James ◽  
...  
Keyword(s):  
South African ◽  
Captive Breeding ◽  
Decapod Crustacean ◽  
Single Species ◽  
Critically Endangered ◽  
Population Declines ◽  
Calanoid Copepods ◽  
Faecal Dna ◽  
Dietary Requirements ◽  
Agricultural Use

AbstractThe estuarine pipefish, Syngnathus watermeyeri, is one of the rarest animals in Africa and occurs in only two South African estuaries. The species was declared provisionally extinct in 1994, but was later rediscovered and is currently listed by the IUCN as Critically Endangered. A conservation programme was launched in 2017, with the re-introduction of captive-bred individuals into estuaries where this species was recorded historically was the main aims. Successful captive breeding requires knowledge of the species’ dietary requirements. In the present study, we used metabarcoding of faecal DNA to identify prey species consumed by wild-captured S. watermeyeri from one of the two surviving populations. We compared the diet of the estuarine pipefish with that of the longsnout pipefish, S. temminckii, in the same estuary, to determine whether these two species compete for the same prey items. Both species occupy similar estuarine habitats, but S. temminckii has a much wider distribution and also occurs in the marine environment. Our results show that even though both pipefish species prey on three major invertebrate classes (Gastropoda, Malacostraca and Maxillopoda), the relative proportions differ. Syngnathus watermeyeri primarily targets Maxillopoda, with a single species of calanoid copepod constituting >95% of the Amplicon Sequence Variants (ASVs) identified from its faecal DNA, whereas the diet of S. temminckii mostly comprises snail and decapod crustacean larvae. Our finding supports the hypothesis that population declines and localised extirpations of S. watermeyeri during previous decades may have been the result of reductions in the abundance of calanoid copepods. Calanoids rely on freshwater pulses to thrive, but such events have become rare in the two estuaries inhabited by S. watermeyeri due to excessive freshwater abstraction for urban and agricultural use.

scholarly journals Food fortification improves the intake of all fortified nutrients, but fails to meet the estimated dietary requirements for vitamins A and B6, riboflavin and zinc, in lactating South African women

2012 ◽  
Vol 15 (10) ◽  
pp. 1810-1817 ◽  
Author(s):  
Peggy C Papathakis ◽  
Kerry E Pearson
Keyword(s):  
South African ◽  
African Women ◽  
Serum Folate ◽  
Zn Deficiency ◽  
Serum Retinol ◽  
Food Records ◽  
Micronutrient Intake ◽  
Dietary Requirements ◽  
South African Women ◽  
The Impact

AbstractObjectiveTo investigate the impact of fortification by comparing food records and selected biochemical indicators of nutritional status pre- and post-fortification.DesignMean intake from 24 h recalls (n 142) was compared with the Estimated Average Requirement (EAR) to determine the proportion with inadequate intake. In a subsample (n 34), diet and serum retinol, folate, ferritin and Zn were compared pre- and post-fortification for fortified nutrients vitamin A, thiamin, riboflavin, niacin, folic acid, Fe and Zn.SettingSouth Africa.SubjectsBreast-feeding women (ninety-four HIV-infected, forty eight HIV-uninfected) measured at ∼6, 14, 24 weeks, and 9 and 12 months postpartum.ResultsPre-fortification, >80 % of women did not meet the EAR for vitamins A, C, D, thiamin, riboflavin, niacin, B6, B12 and folate and minerals Zn, iodine and Ca. Dietary intake post-fortification increased for all fortified nutrients. In post-fortification food records, >70 % did not meet the EAR for Zn and vitamins A, riboflavin and B6. Serum folate and Zn increased significantly post-fortification (P < 0·001 for both), with no change in ferritin and a reduction in retinol. Post-fortification marginal/deficient folate status was reduced (73·5 % pre v. 3·0 % post; P < 0·001), as was Zn deficiency (26·5 % pre v. 5·9 % post; P < 0·05). Pre- and post-fortification, >93 % were retinol replete. There was no change in Fe deficiency (16·7 % pre v. 19·4 % post; P = 0·728).ConclusionsMicronutrient intake improved with fortification, but >70 % of lactating women did not meet the EAR for Zn, vitamins A, riboflavin and B6. Although 100 % exceeded the EAR for Fe after fortification, Fe status did not improve.

scholarly journals A check list of the spider fauna of the Karoo National Park, South Africa (Arachnida: Araneae)

Koedoe ◽  
1999 ◽  
Vol 42 (1) ◽  
Author(s):  
Anna S. Dippenaar-Schoeman ◽  
Astri Leroy ◽  
Marie De Jager ◽  
Annette Van den Berg
Keyword(s):  
South Africa ◽  
South African ◽  
National Survey ◽  
Habitat Preference ◽  
National Park ◽  
Single Species ◽  
Check List ◽  
The South ◽  
Spider Species ◽  
Number Of Species

A check list of the spider species of the Karoo National Park collected over a period of 10 years is presented. Thirty-eight families, represented by 102 genera and 116 species have been collected. Of these species, 76 (66.4 ) were wanderers and 39 (33.6 ) web builders. The Araneidae have the highest number of species (14) followed by the Thomisidae (10) and the Gnaphosidae (8), while 14 families are represented by a single species. Information on spider guilds, their habitat preference and web types is provided. This study forms part of the South African National Survey of Arachnida (SANSA).

Breeding biology of the critically endangered Malherbe's parakeet on Maud Island, New Zealand, following the release of captive-bred individuals

2009 ◽  
Vol 57 (6) ◽  
pp. 433 ◽  
Author(s):  
Luis Ortiz-Catedral ◽  
Jonathan C. Kearvell ◽  
Mark E. Hauber ◽  
Dianne H. Brunton
Keyword(s):  
New Zealand ◽  
Clutch Size ◽  
Captive Breeding ◽  
Breeding Biology ◽  
Critically Endangered ◽  
Limiting Factor ◽  
Early Age ◽  
Small Islands ◽  
Austral Spring ◽  
Nesting Sites

We studied a population of the critically endangered Malherbe’s parakeet (Cyanoramphus malherbi), following the release of 62 captive-bred individuals on Maud Island, New Zealand, to identify and characterise nesting sites in a novel island environment. Previous work on Malherbe’s parakeets consisted of limited observations on remnant mainland populations. The age of breeding pairs on Maud Island was 7.2 ± 4.7 months and included both captive-bred individuals of the first release flock and individuals hatched on Maud Island within a year of the first release. Nests were found in hollows of mamaku (Cyathea medullaris), vacant nests of sacred kingfisher (Todiramphus sanctus), a hole in the ground and a hollow in a kohekohe (Disoxylum spectabile). Active nests were found in the austral spring, summer and autumn. Clutch size was 5 eggs. The fledging of three Malherbe’s parakeets was confirmed for one nest 43 days after hatching. Observations of newly fledged individuals around the island indicate that at least seven successful nesting attempts occurred. Consistent with other studies in Cyanoramphus parakeets, our results suggest that availability of nesting sites on small islands may not be a limiting factor for the establishment of additional populations of Malherbe’s parakeets via captive breeding and translocation. The formation of breeding pairs at an early age, the use of diverse nesting sites in regenerating vegetation, and the evidence of successful breeding shortly after release on an island represent encouraging prospects for the conservation of New Zealand’s rarest parakeet.

116 DEVELOPMENT OF ASSISTED REPRODUCTION TECHNOLOGIES FOR THE ENDANGERED MISSISSIPPI GOPHER FROG (RANA SEVOSA) AND SPERM TRANSFER FOR IN VITRO FERTILIZATION

2012 ◽  
Vol 24 (1) ◽  
pp. 170 ◽  
Author(s):  
A. Kouba ◽  
E. Willis ◽  
C. Vance ◽  
S. Hasenstab ◽  
S. Reichling ◽  
...  
Keyword(s):  
Captive Breeding ◽  
Assisted Reproductive Technologies ◽  
Sperm Concentration ◽  
Reproductive Technologies ◽  
Critically Endangered ◽  
Leopard Frog ◽  
Genetic Management ◽  
Mississippi Gopher Frog

Species-specific differences in breeding strategies and physiology have limited the application of assisted reproductive technologies (ART) for critically endangered amphibians in captive assurance colonies. In 2006, the Memphis Zoo (MZ) initiated a program to develop ART for the critically endangered Mississippi gopher frog after natural breeding failed. Standard gamete collection and IVF developed by MZ for reproducing endangered toads such as the Wyoming or boreal toad were applied to the gopher frog with little success, especially hormonal therapy for sperm production. Using the leopard frog as a model species for Ranids, we tested the time and dose dependence of a luteinizing hormone releasing hormone analogue (LHRHa) and hCG on sperm quantity and quality. Initial findings from the leopard frog study were critical in designing the study on gopher frogs. Our objectives were to (1) compare 2 different hormones administered intraperitoneal (500 IU hCG vs 15 μg LHRHa) or their combination on spermiation in gopher frogs; (2) develop in vivo oocyte maturation and ovulation protocols using LHRHa (15 μg) and hCG (500 IU); and (3) transfer this technology to another institution as proof of principle. In gopher frogs, 100 and 83% of the males produced sperm in response to the LHRHa and the combination treatment, respectively, whereas only 16% responded to hCG alone. Sperm concentration peaked at 1 h post-administration for all treatments, with the LHRH/hCG cocktail treatment producing the highest concentration of sperm (mean = 4.6 × 106 ± 1.2 × 106 sperm mL–1, n = 6). No differences in motility were observed between treatments (P > 0.05). For females, a series of priming hormones of hCG and LHRHa were given several months before an ovulatory hormone regimen resulting in ovulation by 100% of the females (n = 6), whereas animals not primed failed to ovulate (n = 4). These 3 separate priming and IVF trials conducted between 2008 and 2010 resulted in each female laying ∼2000 eggs, with an average fertilization rate of 76% for inseminated eggs and hundreds of tadpoles produced. These IVF tadpoles represent the first captive reproduction of gopher frogs and highlight how ART can be applied to conservation and genetic management of threatened species. Subsequently, we tested our IVF protocols on gopher frogs at Omaha's Henry Doorly Zoo using fresh (collected on site) and chilled, shipped sperm from MZ. We collected 6169 eggs from 9 hormone-primed females with all animals ovulating. A portion of the total eggs ovulated were inseminated, resulting in 2401 fertilized eggs (38.9% of total eggs collected) across 18 different male–female pairings leading to viable tadpoles. In addition, sperm transferred overnight from the MZ produced 202/441 fertilized eggs (46%). The transfer of this technology and production of endangered amphibians using chilled, shipped sperm from live animals is a conservation milestone that can be applied to other captive breeding programs.

Reproductive potential of South African thermophilic Meloidogyne populations, with special reference to Meloidogyne enterolobii

Nematology ◽  
2019 ◽  
Vol 21 (9) ◽  
pp. 913-921 ◽  
Author(s):  
Milad Rashidifard ◽  
Mariette Marais ◽  
Mieke S. Daneel ◽  
Hendrika Fourie
Keyword(s):  
South African ◽  
Management Strategies ◽  
Reproductive Potential ◽  
Single Species ◽  
Mixed Species ◽  
Initial Experiment ◽  
Meloidogyne Enterolobii ◽  
Species Population ◽  
Rf Values ◽  
Single Species Population

Summary Variability in the reproductive potential of Meloidogyne spp. is crucial to design suitable nematode management strategies. The reproductive potential of nine South African single-species Meloidogyne populations, M. enterolobii (5), M. incognita (2) and M. javanica (2), as well as three mixed-species communities (each containing two of the three species) were determined in glasshouse experiments. A mixed-species community of M. enterolobii and M. javanica had the highest reproductive potential (Rf = 15.7) in the initial experiment. For the repeat experiment, a single-species population of M. javanica was the most injurious (Rf = 19.1). Conversely, a single-species population of M. enterolobii had the lowest Rf values in the initial (Rf = 1.0) and repeat (Rf = 6.1) experiments. Substantial variation existed in terms of the reproductive potential of M. enterolobii single-species populations and mixed-species communities.

South African Practice in Land Disposal of Sludge, Including Legislation and Health Aspects – An Overview

1983 ◽  
Vol 15 (1) ◽  
pp. 151-155 ◽  
Author(s):  
G Oberholster
Keyword(s):  
Sewage Sludge ◽  
South African ◽  
Short Overview ◽  
Agricultural Use ◽  
Land Disposal

A Short overview of South African practice in the land disposal of sewage sludge is given, the applicable legislation is cited and guidelines for the agricultural use of sewage sludge are introduced.

Captive breeding and rearing of critically endangered Mauritius fodiesFoudia rubrafor reintroduction

Zoo Biology ◽  
2008 ◽  
Vol 27 (4) ◽  
pp. 255-268 ◽  
Author(s):  
Andrew Cristinacce ◽  
Amanda Ladkoo ◽  
Richard Switzer ◽  
Lara Jordan ◽  
Vanessa Vencatasamy ◽  
...  
Keyword(s):  
Captive Breeding ◽  
Critically Endangered

scholarly journals Suitability of the Decentralised Wastewater Treatment Effluent for Agricultural Use: Decision Support System Approach

Water ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 2454
Author(s):  
William Musazura ◽  
Alfred O. Odindo
Keyword(s):  
Wastewater Treatment ◽  
Decision Support ◽  
Decision Support System ◽  
South African ◽  
Support System ◽  
Low Income ◽  
Nutrient Loading ◽  
Crop Yields ◽  
Treated Wastewater ◽  
Agricultural Use

The decentralised wastewater treatment system (DEWATS) is an onsite sanitation technology that can be used in areas away from municipal sewerage networks. The discharge of effluent emanating from DEWATS into water bodies may cause pollution. Agricultural use of the effluent may improve crop yields and quality thereby contributing to food security in low-income communities. There are drawbacks to the agricultural use of treated wastewater. Therefore, the study assessed the crop, environmental and health risks when irrigating with anaerobic filter (AF) effluent using the Decision Support System (DSS) of the South African Water Quality Guideline model, in four South African agroecological regions, three soil types, two irrigation systems and three different crops. The model was parameterised using AF effluent characterisation data and simulated for 45 years. The model predicted that there are no negative impacts for using AF effluent on soil quality parameters (root zone salinity, soil permeability and oxidisable carbon loading), leaf scorching and irrigation equipment. The problems were reported for nutrient loading (N and P) in maize and microbial contamination in cabbage and lettuce. It was recommended that the effluent should be diluted when used for maize production and advanced treatment should be explored to allow unrestricted agricultural use.

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