Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 3 de 3
Filter
Add more filters











Database
Language
Publication year range
1.
J Morphol ; 284(1): e21547, 2023 01.
Article in English | MEDLINE | ID: mdl-36533732

ABSTRACT

The mandibular apparatus of batoids (skates, electric rays, guitarfishes, stingrays, and sawfishes) is composed of a few skeletal elements to which the muscular bundles, responsible for all movements involved in the feeding mechanism, are inserted. The description of the different mandibular morphologies can help to understand the different feeding guilds in this group. In this study, we examined the cranio-mandibular myology of adult Rostroraja velezi, Narcine entemedor, and Zapteryx exasperata, three species of rays that coexist in the Southern Gulf of California, Mexico. This study described the muscles on the ventral and the dorsal surfaces for each species, identified the origins and insertions of these muscles, as well as the general characteristics of muscle morphology. There were 17 and 18 muscle bundles attached to the feeding apparatus, including five on the dorsal surface. Only the levator rostri, which elevates the rostrum during feeding, showed considerable differences in shape and size among species. The muscles of the adductor complex showed the greatest differences in size among the three species. N. entemedor presented the exclusive muscle X in the lower mandibular area and the extreme reduction of the coracohyoideus in the pharyngeal area derived from the absence of the basihyal cartilage. The information generated in our study supports the morphological specialization of electric rays (N. entemedor) for an almost exclusive suction feeding strategy.


Subject(s)
Skates, Fish , Animals , Mexico , Skates, Fish/anatomy & histology , Mandible/anatomy & histology , Torpedo/anatomy & histology , Muscle, Skeletal/anatomy & histology
2.
J Fish Biol ; 102(2): 413-425, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36433741

ABSTRACT

Allometric growth is a common feature during fish larval development. It has been proposed as a growth strategy to prioritize the development of body segments related to primordial functions like feeding and swimming to increase the probability of survival during this critical period. In the present study we evaluated the allometric growth patterns of body segments associated to swimming and feeding during the larval stages of Pacific red snapper Lutjanus peru. The larvae were kept under intensive culture conditions and sampled every day from hatching until day 33 after hatching. Each larva was classified according to its developmental stage into yolk-sac larva, preflexion larva, flexion larva or postflexion larva, measured and the allometric growth coefficient of different body segments was evaluated using the potential model. Based on the results we can infer the presence of different ontogenetic priorities during the first developmental stages associated with vital functions like swimming during the yolk-sac stage [total length (TL) interval = 2.27-3.005 mm] and feeding during the preflexion stage (TL interval = 3.007-5.60 mm) by promoting the accelerated growth of tail (post anal) and head, respectively. In the flexion stage (TL interval = 5.61-7.62 mm) a change in growth coefficients of most body segments compared to the previous stage was detected, suggesting a shift in growth priorities. Finally, in the postflexion stage (TL interval = 7.60-15.48 mm) a clear tendency to isometry in most body segments was observed, suggesting that growth priorities have been fulfilled and the larvae will initiate with the transformation into a juvenile. These results provide a framework of the larval growth of L. peru in culture conditions which can be useful for comparative studies with other species or in aquaculture to evaluate the changes in larval growth due to new conditions or feeding protocols.


Subject(s)
Fishes , Perciformes , Animals , Peru , Larva , Yolk Sac
3.
J Fish Biol ; 98(5): 1349-1362, 2021 May.
Article in English | MEDLINE | ID: mdl-33410520

ABSTRACT

We report the effects of food deprivation on the early development of Pacific red snapper Lutjanus peru during the first days of development. The point of no return (PNR) was determined using the feeding incidence after a delay in first feeding. The gradual deterioration of the larvae during food deprivation was recorded using morphometric, histological, enzymatic and biochemical analysis. The time to reach the PNR was 120 h after hatching. Morphologically, the total length, muscle height, head length, tail length and pectoral angle showed the biggest reductions and their growth coefficients changed significantly during food deprivation. Histologically, enterocyte height also was reduced significantly. The protein concentration and activities of the digestive enzymes trypsin, cathepsin-like and lipase showed a significant decrease; meanwhile, amylase activity remained constant during food deprivation. The concentration of total essential free amino acids (EFAAs) decreased significantly while that of the nonessential free amino acids (NEFAAs) remain stable during food deprivation. The most abundant EFAAs were lysine, leucine, isoleucine and valine; the most abundant NEFAAs were alanine, glycine and glutamate, suggesting a more prominent role as energy substrates. At the time of the PNR the concentration of almost all the free amino acids showed a significant decrease. Early food deprivation has a significant impact on the morphology and biochemical characteristics of L. peru. These results suggest that initial feeding of L. peru should begin within 3 days of yolk sac depletion to avoid the PNR. Further studies are necessary to confirm and validate the characters identified in this study as biomarkers of starvation under culture conditions and evaluate their possible utility in ichthyoplankton surveys.


Subject(s)
Enterocytes/cytology , Food Deprivation , Muscles/cytology , Perciformes/anatomy & histology , Perciformes/growth & development , Amino Acids/blood , Animals , Enterocytes/pathology , Muscles/chemistry , Muscles/pathology , Perciformes/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL