Ontogenetic variation of food intake and gut evacuation rate in larvae of the doncellaPseudoplatystoma punctifer, as measured using a non-destructive method

Abstract

Food intake (FI) and gut evacuation (Rg) were measured in larvae of Pseudoplatystoma punctifer (4.5–18.4 mm SL) fed Artemia nauplii, taking advantage of the translucence of their abdominal region to achieve this in a non‐destructive way, using digital photographs and mathematical reconstruction of gut volume content (ellipsoidal and cylindrical models for stomach and intestine respectively). The inaccuracy of the method, with reference to counts of nauplii following fish dissection, was low (2.9 ± 1.5%) and independent of fish size (P = 0.6153). Pigmentation hampered measurement in fish >18–19 mm SL. Anaesthesia was needed in fish >9.5 mm SL, thereby preventing the measurement of Rg in individual fish. The FI increased rapidly during the ontogeny, passing from <7% M at 0.6 mg, to 14% M at 1 mg and 21% M at 15–40 mg, and then decreased slightly in larger fish. At 28.5°C, Rg (% M h−1) was modelled as Rg = −8.22 + 12.11 log FI + 6.30 log M – 12.67 (log M)2 (R2 = 0.904, d.f. = 27, with FI in% M and M in mg). Extrapolations of Rg over 24 h gave estimates of daily food rations that fit well with those measured in cannibalistic P. punctifer.

Improving feed efficiency in fish using selective breeding: a review

“…; Tuene & Nortvedt ; Hughes & Kelly ; Damsgard & Ugedal ; Ang & Petrell ; Baras et al . ; de Verdal et al . ).…”

“…The last method consists in direct observation or video recording of individual daily feed intake (Adams et al 1995;Smith et al 1995;Tuene & Nortvedt 1995;Hughes & Kelly 1996;Damsgard & Ugedal 1997;Ang & Petrell 1997;Baras et al 2012;de Verdal et al 2017). Feed consumption can be measured for each fish by counting the number of eaten pellets during a given time span.…”

Ontogeny of the digestive enzyme activity of the Amazonian pimelodid catfish Pseudoplatystoma punctifer (Castelnau, 1855)

“…In Brazil, the country producing most of Pseudoplatystoma reared fish, commercial aquaculture is mostly centered on producing hybrids of Pseudoplatystoma corruscans and Pseudoplatystoma reticulatum (Valladão et al, 2018), which accept formulated feeds during early life stages more easily than pure species and hence present less cannibalism and a better growth performance (Porto-Foresti et al, 2013). Taking into consideration the risk of genetic variability loss through genetic introgression caused by the escape of interspecific hybrids to the natural environment (Vaini et al, 2014;Lima et al, 2018), research efforts have been made in Amazonia to develop the culture of Pseudoplatystoma punctifer (Castro-Ruiz, et al, 2009Nuñez et al, 2011;Baras et al, 2011Baras et al, , 2012Gilles et al, 2014;Gisbert et al, 2014;Darias et al, 2015a;Fernández-Méndez et al, 2015;among others). This carnivorous migratory tropical catfish species, native to the Amazon basin, can attain 140 cm of total length (Buitrago-Suárez & Burr, 2007).…”

EVALUACIÓN DE LA INFLUENCIA PARENTAL EN RELACIÓN AL CRECIMIENTO Y SUPERVENCIA LARVAL EN FAMILIAS DE LA doncella Pseudoplatystoma punctifer

“…A pesar de haberse realizado varios estudios para controlar el ciclo de vida completo de esta especie en ambientes controlados Fernández et al, 2015;Gisbert et al, 2014;Nuñez et al, 2008;Nuñez et al, 2009;Nuñez et al, 2011;Baras et al, 2011;Baras et al, 2012) su acuicultura a gran escala, aún no se ha implementado en el Perú. Una de las limitantes es la baja tasa de supervivencia en la última etapa larval y juvenil así como también la aparición de manera precoz de individuos de mayor tamaño denominados "jumpers" capaces de ejercer depredación sobre las larvas más pequeñas, ocasionando altas tasas de mortalidad.…”