scholarly journals Scraping and grazing herbivorous/detritivorous fish display opposite feeding behaviours under different protection regulations

2021 ◽  
Author(s):  
Nathan William Price ◽  
Kao-Sung Chen ◽  
Chaolun Allen Chen ◽  
Colin Kuo-Chang Wen
Keyword(s):  
Coral Reefs ◽  
Functional Groups ◽  
Marine Protected Areas ◽  
Feeding Behaviour ◽  
Feeding Rate ◽  
Feeding Rates ◽  
Benthic Community Structure ◽  
Reef Fish Species ◽  
Feeding Behaviours ◽  
Detritivorous Fish

Abstract Background:Functional groups, especially herbivorous fishes, are important for mediating benthic community structure on coral reefs. Herbivorous and detritivorous fish display complex feeding behaviour, and research into schooling feeding behaviour and feeding rates, and how these change with environmental and social behavioural variables is lacking. Such knowledge is imperative to infer how herbivory/detritivory will change, in light of changing resources and communities, specifically whether reefs can recover from disturbance. Differences in abundance, feeding rate, body length, diet preferences, and schooling size of three major functional groups, scrapers, grazers and browsers were examined across reef habitats under different fishing regulations, such as no-take restricted zones and open-fishing general use zones. Although marine protected areas have been implemented to conserve reef fish species; further precise management based on ecological behaviour of functional groups is necessary.Results:Scrapers and grazers which were mostly parrotfishes and surgeonfishes were more abundant on reef flats and also displayed the highest feeding rates on reef flats. Although scrapers mainly resided inside the restricted zone, more grazers were found in the general use zone where macroalgae abundance was highest, indicating a higher availability of nutritional resources. Browsers, mostly rabbitfishes, were seldom observed and patchily gathered on the reef flat and slope in both zones. Thus, fishing protection did not appear to benefit grazers and browsers, whereas scrapers gathered on shallow reef flats in the protection zone. Lastly, scraper and grazer feeding rates increased from an individual to paired feeding, and increased with body size, these factors led to variations in feeding behaviours on different habitats under different protection regulations.Conclusions:Fishing protection benefits scrapers which subsequently appears to be resulting in a reduction in algal coverage, and variation in feeding rates was largely related to school sizes. The density of these functionally important grazers was influenced more by changes to benthic composition than protection status. The opposite feeding behaviours of two herbivorous/detritivorous functional groups indicates not only protection status, but fishing gear and size limit regulations are needed to help maintain fisheries and diversity on coral reefs in Taiwan.

scholarly journals Widespread zoophagy and detection of Plasmodium spp. in Anopheles mosquitoes in southeastern Madagascar

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Micaela Finney ◽  
Benjamin A. McKenzie ◽  
Bernadette Rabaovola ◽  
Alice Sutcliffe ◽  
Ellen Dotson ◽  
...  
Keyword(s):  
Plasmodium Falciparum ◽  
Vector Control ◽  
Plasmodium Vivax ◽  
Malaria Control ◽  
Feeding Behaviour ◽  
Enzyme Linked Immunosorbent Assay ◽  
Habitat Gradient ◽  
Blood Meals ◽  
Feeding Behaviours ◽  
Southeastern Madagascar

Abstract Background Malaria is a top cause of mortality on the island nation of Madagascar, where many rural communities rely on subsistence agriculture and livestock production. Understanding feeding behaviours of Anopheles in this landscape is crucial for optimizing malaria control and prevention strategies. Previous studies in southeastern Madagascar have shown that Anopheles mosquitoes are more frequently captured within 50 m of livestock. However, it remains unknown whether these mosquitoes preferentially feed on livestock. Here, mosquito blood meal sources and Plasmodium sporozoite rates were determined to evaluate patterns of feeding behaviour in Anopheles spp. and malaria transmission in southeastern Madagascar. Methods Across a habitat gradient in southeastern Madagascar 7762 female Anopheles spp. mosquitoes were collected. Of the captured mosquitoes, 492 were visibly blood fed and morphologically identifiable, and a direct enzyme-linked immunosorbent assay (ELISA) was used to test for swine, cattle, chicken, human, and dog blood among these specimens. Host species identification was confirmed for multiple blood meals using PCR along with Sanger sequencing. Additionally, 1,607 Anopheles spp. were screened for the presence of Plasmodium falciparum, P. vivax-210, and P. vivax 247 circumsporozoites (cs) by ELISA. Results Cattle and swine accounted, respectively, for 51% and 41% of all blood meals, with the remaining 8% split between domesticated animals and humans. Of the 1,607 Anopheles spp. screened for Plasmodium falciparum, Plasmodium vivax 210, and Plasmodium vivax 247 cs-protein, 45 tested positive, the most prevalent being P. vivax 247, followed by P. vivax 210 and P. falciparum. Both variants of P. vivax were observed in secondary vectors, including Anopheles squamosus/cydippis, Anopheles coustani, and unknown Anopheles spp. Furthermore, evidence of coinfection of P. falciparum and P. vivax 210 in Anopheles gambiae sensu lato (s.l.) was found. Conclusions Here, feeding behaviour of Anopheles spp. mosquitoes in southeastern Madagascar was evaluated, in a livestock rich landscape. These findings suggest largely zoophagic feeding behaviors of Anopheles spp., including An. gambiae s.l. and presence of both P. vivax and P. falciparum sporozoites in Anopheles spp. A discordance between P. vivax reports in mosquitoes and humans exists, suggesting high prevalence of P. vivax circulating in vectors in the ecosystem despite low reports of clinical vivax malaria in humans in Madagascar. Vector surveillance of P. vivax may be relevant to malaria control and elimination efforts in Madagascar. At present, the high proportion of livestock blood meals in Madagascar may play a role in buffering (zooprophylaxis) or amplifying (zoopotentiation) the impacts of malaria. With malaria vector control efforts focused on indoor feeding behaviours, complementary approaches, such as endectocide-aided vector control in livestock may be an effective strategy for malaria reduction in Madagascar.

scholarly journals Association of Feed Efficiency, Feeding Rate, and Behaviour with the Milk Performance of Dairy Cows

Dairy ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 684-694
Author(s):  
Lenka Krpálková ◽  
Niall O’Mahony ◽  
Anderson Carvalho ◽  
Sean Campbell ◽  
Gerard Corkery ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Milk Production ◽  
Milk Yield ◽  
Feed Intake ◽  
Feed Efficiency ◽  
Feeding Behaviour ◽  
Feeding Rate ◽  
Feeding Time ◽  
Feed Conversion ◽  
Milk Performance

Identification of the associations of cow feed efficiency with feeding behaviour and milk production is important for supporting recommendations of strategies that optimise milk yield. The objective of this study was to identify associations between measures of feed efficiency, feed intake, feeding rate, rumination time, feeding time, and milk production using data collected from 26 dairy cows during a 3 month period in 2018. Cows averaged (mean ± standard deviation) 2.2 ± 1.7 lactations, 128 ± 40 days in milk, 27.5 ± 5.5 kg/day milk, 1.95 ± 0.69 kg feed/1 kg milk—the measure used to express feed conversion ratio (FCR), 575 ± 72 min/day rumination time, and 264 ± 67 min/day feeding time during the observation period. The coefficient of variation for rumination time (min/d) was 12.5%. A mixed linear model was selected for analyses. The most feed inefficient cows with the highest FCR (≥2.6 kg feed/1 kg milk) showed the lowest milk yield (24.8 kg/day), highest feed intake (78.8 kg), highest feeding rate (0.26 kg/min) and BCS (3.35 point). However, the relative milk yield (milk yield per 100 kg of body weight) was the highest (4.01 kg/day) in the most efficient group with the lowest FCR (≤1.4 kg feed/1 kg milk). Our study showed that the most efficient cows with the lowest FCR (≤1.4 kg feed/1 kg milk) had the highest rumination time (597 min/day; p < 0.05), feeding time (298 min/day; p < 0.05), rumination/activity ratio (4.39; p < 0.05) and rumination/feeding ratio (2.04; p < 0.05). Less active cows (activity time 164 min/day; p < 0.05) were the most efficient cows with the lowest FCR (≤1.4 kg feed/1 kg milk). The behavioural differences observed in this study provide new insight into the association of feed behaviour and feed efficiency with milk performance. Incorporating feeding behaviour into the dry matter intake model can improve its accuracy in the future and benefit breeding programmes.

scholarly journals The association of Lantana camara with elephant (Elephas maximus), their food, habitat use and feeding behaviour in southern India

2021 ◽  
Author(s):  
◽  
Gaius Wilson
Keyword(s):  
Habitat Use ◽  
Feeding Behaviour ◽  
Invasive Plant ◽  
Deciduous Forest ◽  
Plant Invasions ◽  
Lantana Camara ◽  
Exotic Plant ◽  
Species Assemblage ◽  
Grass Cover ◽  
Feeding Rates

<p>Invasive exotic species pose an enormous threat to the world's biological diversity. Invasions can alter native communities, replacing local biotas with non-indigenous species introduced by humans. Exotic plant invasions can have negative effects on native flora, which can be in turn detrimental to the herbivores that depend on the vegetation. In this dissertation, I examined the association of an exotic invasive weed, Lantana camara L., with the Asian elephant (Elephas maximus), its food resources (grass and browse), habitat use and feeding behaviour in Mudumalai Tiger Reserve, southern India.  Exotic plant invasions are often associated with alterations or declines in native floral species. I first examined the association of L. camara and measured environmental covariates with floral species assemblage and richness, elephant browse plants, percentage grass cover and percentage grass occupancy. A multivariate analysis revealed a significant association of L. camara with floral species assemblage and richness, some elephant browse plants and grass cover within the moist deciduous forest (MDF) and dry deciduous forest (DDF), but not in the thorn forest (TF) of Mudumalai. My results suggest that L. camara appears to be capable of altering the floral community in some habitats. These results also suggest that changes in the floral community and a reduction in grass cover due to L. camara invasion could be detrimental to elephant and other herbivores that depend on grass in this reserve.   I then examined the association of L. camara with habitat use by elephant. Elephant dung density was used to assess elephant habitat use from 62 line transects, each 1-km in length. I found no evidence that L. camara was associated with elephant habitat use across habitats, although the interaction term between one habitat (DDF) and L. camara was significantly associated with elephant dung density suggesting that the effect of L. camara was different in different habitats. This indicates that L. camara is associated with elephant habitat use within certain habitats. Habitat and impact of human settlements were significantly associated with elephant habitat use across habitats within Mudumalai. In the DDF, however, only L. camara was associated with elephant habitat use. I conclude that while no significant effects of L. camara were seen across habitats, in specific habitats, negative associations of this invasive plant with elephant habitat use, possibly through the reduction of grass cover, are possible. These results indicate that L. camara appears detrimental to elephant in certain habitats and removal of L. camara in these habitats should be prioritised so as to facilitate growth of grass and native browse species, especially if elephant populations continue to expand.  Lastly, I examined the association of elephant behaviour, assessed from feeding and stepping rates, with variation in L. camara invasion. Fifty-seven elephants were observed for a total of 64.3 hours using the focal-animal sampling method. Elephant were never observed to feed on L. camara, but rather fed on grass and browse that were present within and around L. camara patches. Feeding rates (number of trunksful·min⁻¹) were negatively associated with L. camara invasion. A path analysis, which assesses both direct and indirect effects of independent variables, indicated that the total effect of L. camara on feeding rates was 11% less than the direct negative association owing to a positive indirect relationship between L. camara and feeding rates through grass cover and browse density. Lantana camara was not significantly associated with variation in stepping rates (number of steps·min⁻¹). Rather, stepping rates were negatively associated with grass cover and positively associated with browse density. My results indicate that L. camara is potentially capable of changing elephant feeding rates, likely through a loss of grass areas due to L. camara invasion.  Wild elephants do not eat L. camara, and this invasive plant appears to take the place of an important food source. My results indicate that managers should prioritize their focus on certain habitats to control the impact of L. camara on elephants and vegetation. However, this study was of a correlational nature based on observational data. Experimental work is therefore needed to test for causal relationships among the variables I measured, over multiple seasons and in different habitats. Experimental evidence will enhance our understanding of how invasive weeds modify floral communities, elephant habitat use and behaviour and help determine whether L. camara is a 'passenger' or 'driver' of these changes in this ecosystem.</p>

scholarly journals KONDISI IKAN KARANG FAMILI CHAETODONTIDAE DI DAERAH PERLINDUNGAN LAUT DESA BAHOI KECAMATAN LIKUPANG BARAT KABUPATEN MINAHASA UTARA

2015 ◽  
Vol 2 (3) ◽  
pp. 92
Author(s):  
Jacqline Laikun ◽  
Ari B Rondonuwu ◽  
Unstain N.W.J. Rembet
Keyword(s):  
Spatial Distribution ◽  
Coral Reef ◽  
Coral Reefs ◽  
Protected Areas ◽  
Reef Fish ◽  
Marine Protected Areas ◽  
Visual Census ◽  
Fish Family ◽  
Marine Life ◽  
Reef Condition

The coral reefs are a sundry of marine life. Which one is reef fish in family Chaetodontidae. This fish is  indicator of the coral reef condition. The aim from the research is : discover of spatial distribution of the reef fish family Chaetodontidae and find out of the intercourse of reef fish family Chaetodontidae with the coral reef presence based on growth of coral form. The research was do in the coral reef at Marine Protected Areas in Bahoi Village District of West Likupang North Minahasa Regency, on Tuesday, December 23rd, 2014. The research is using to do the surveying method. The data is collecting distribution of the fish Chaetodontidae (amount from species and individuals to using by technic visual census). The total of reef fish family Chaetodontidae those found in Marina Protected Areas in Bahoi Village is about 20 species, with total of the individuals at a depth of 3 meters and 10 meters is (56,66 and 57,33 individuals/150m2). Keywords : Coral reefs, Chaetodontidae, Bahoi   ABSTRAK Terumbu karang merupakan tempat berbagai macam biota laut. Salah satu Ikan karang adalah ikan famili Chaetodontidae. Ikan ini merupakan ikan indikator terumbu karang. Tujuan dari penelitian ini : mengetahui kelimpahan dari ikan karang famili Chaetodontidae. Penelitian ini dilakukan di Daerah Perlindungan Laut Desa Bahoi Kecamatan Likupang Barat Kabupaten Minahasa Utara, pada hari selasa, tanggal 23 Desember 2014. Penelitian ini menggunakan metode survey. Data yang dikumpulkan adalah kelimpahan ikan Chaetodontidae (Jumlah spesies dan individu dengan menggunakan teknik sensus visual). Jumlah ikan karang famili Chaetodontidae yang di temukan di Daerah Perlindungan Laut Desa Bahoi berjumlah 20 spesies, dengan jumlah individu pada kedalaman 3 meter dan 10 meter berjumlah (56,66 individu/150m2 dan 57,33/150m2 individu). Kata kunci : Terumbu karang, Chaetodontidae, Bahoi 1Bagian dari skripsi 2Mahasiswa Program Studi Manajemen Sumberdaya Perairan FPIK-UNSRAT 3Staf pengajar Fakultas Perikanan dan Ilmu Kelautan Universitas Sam Ratulangi

scholarly journals X-ray microtomography provides first data about the feeding behaviour of an endangered lizard, the Montserrat galliwasp ( Diploglossus montisserrati )

2015 ◽  
Vol 2 (12) ◽  
pp. 150461 ◽  
Author(s):  
C. Bochaton ◽  
R. Boistel ◽  
L. Charles
Keyword(s):  
Feeding Behaviour ◽  
Freshwater Snail ◽  
Feeding Habit ◽  
Morphological Evidence ◽  
Museum Specimens ◽  
X Ray ◽  
Non Destructive ◽  
Shell Fragments ◽  
Freshwater Environments ◽  
Feeding Behaviours

Reporting the diet of recently extinct or very rare taxa, only known by a few museum specimens, is challenging. This study uses X-ray microtomography, a non-destructive investigation method, to obtain the first data about feeding behaviours in the Montserrat galliwasp ( Diploglossus montisserrati ) by scanning one of the two specimens known to date. The scans revealed the occurrence of shell fragments of a freshwater snail ( Omalonyx matheroni ) in the digestive tract of the specimen. This data combined with morphological evidence shows the occurrence of a durophagous feeding habit and a possible tendency of association with freshwater environments. This information could be crucial to save this critically endangered lizard endemic on Montserrat island.

Spectral analysis of feeding patterns of steers divergent in residual feed intake

2008 ◽  
Vol 48 (7) ◽  
pp. 843 ◽  
Author(s):  
Robin Dobos ◽  
Robert Herd
Keyword(s):  
Spectral Analysis ◽  
Feed Intake ◽  
Feed Efficiency ◽  
Feeding Behaviour ◽  
Feeding Rate ◽  
Residual Feed Intake ◽  
Selection Line ◽  
Feeding Patterns ◽  
Time Spent Feeding ◽  
Efficient Selection

Spectral analysis was used to quantify differences in feeding patterns of Angus steers genetically divergent in residual feed intake (RFI). Forty-two low RFI (more efficient) and 28 high RFI (less efficient) selection line steers were fed a feedlot diet through electronic feeders for 72 days. Mean (±s.e.) daily feed intake was 11.9 ± 0.076 and 12.7 ± 0.095 kg dry matter/day over the 72-day feeding period for low and high RFI steers, respectively. The high RFI steers exhibited different temporal cycles to the low RFI steers in daily feed intake and time spent feeding. However, patterns of number of eating sessions, feeding rate, the time spent eating and the number of eating sessions were similar. Further analysis of daily (24 h) feeding behaviour is required to help improve our understanding of the association between feeding behaviour and feed efficiency.

scholarly journals Expanding marine protected areas to include degraded coral reefs

2016 ◽  
Vol 30 (6) ◽  
pp. 1182-1191 ◽  
Author(s):  
A. Abelson ◽  
P.A. Nelson ◽  
G.J. Edgar ◽  
N. Shashar ◽  
D.C. Reed ◽  
...  
Keyword(s):  
Coral Reefs ◽  
Protected Areas ◽  
Marine Protected Areas

Comparative Field Energetics of Two Macropod Marsupials and a Ruminant.

1990 ◽  
Vol 17 (6) ◽  
pp. 591 ◽  
Author(s):  
KA Nagy ◽  
GD Sanson ◽  
NK Jacobsen
Keyword(s):  
Feeding Rate ◽  
Energy Content ◽  
Metabolizable Energy ◽  
Ecological Modelling ◽  
Feeding Rates ◽  
Doubly Labelled Water ◽  
Water Influx ◽  
Scaling Relationship ◽  
Field Metabolic Rates ◽  
Free Ranging

Field metabolic rates (FMRs) and water influx rates were measured via the doubly labelled water method in wild Tasmanian pademelons and grey kangaroos living in the Jock Marshall Reserve at Clayton, Victoria, and in wild black-tailed deer free-ranging within a nature reserve at Davis, California. Deer expended more than 3 times more energy per day than similar sized grey kangaroos. Feeding rates required to achieve energy balance were estimated from FMRs along with an estimate of metabolizable energy content of the food. The estimated feeding rates for pademelons and kangaroos were combined with similar values for 5 other species of macropods to calculate an allometric (scaling) relationship for food requirements of macropod marsupials. Feeding rate had the following relationship to body mass: g food (DM) consumed per day = 0.20 g body mass0.79 (r2 = 0.94). The findings reported herein should be useful for predicting the approximate food requirements of free-ranging macropods and deer for purposes of ecological modelling, conservation efforts and management programmes.

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