01508nas a2200157 4500008004100000245012600041210006900167260001200236300001100248490000700259520090100266653001101167100002001178700002101198856013101219 1997 eng d00aSpawning frequency and batch fecundity of horse mackerel, Trachurus trachurus (L.), in the Saronikos Gulf (Greece)0 aSpawning frequency and batch fecundity of horse mackerel iTrachu c1997/// a97-1040 v133 aHorse mackerel, Trachurus trachurus (L.), is a multiple spawning fish with most probably an indeterminate fecundity. Histological sections of gonads were used to identify the hydrated oocytes, the migratory-nucleus stage oocytes, and the new and old post-ovulatory follicles. Spawning frequency determination, based on the mean percentage estimation of the females that occurred in different spawning states such as migratory-nucleus stage oocytes and post-ovulatory follicles during two successive reproductive periods, was found to average once every 5.8 and 4.8 days, respectively. High spawning frequency was observed at the peak of spawning. Relative batch fecundity of 205 oocytes/g fish weight was estimated by the hydrated and migratory-nucleus method. Since potential annual spawnings were found to be equal to 16, potential annual relative fecundity could be 3280 oocytes/g fish weight.10aPisces1 aKarlou-Riga, C.1 aEconomidis, P.S. uhttps://icgf.myspecies.info/content/spawning-frequency-and-batch-fecundity-horse-mackerel-trachurus-trachurus-l-saronikos-gulf02119nas a2200217 4500008004100000245010500041210006900146260001200215300001200227490000700239520142200246653000801668653001101676653001801687653001301705653001101718653002401729100002001753700001401773856011401787 1997 eng d00aAge and growth of horse mackerel, Trachurus trachurus (L.), in the Gulf of Saronikos (Greece)0 aAge and growth of horse mackerel iTrachurus trachurus iL in the  c1997/// a157-1710 v323 aThe age and growth of horse mackerel, Trachurus trachurus (L.), were studied in the Gulf of Saronikos (Greece) during the years 1989-1991. Length frequency based on a total of 6791 specimens was followed by month, while age reading was undertaken on 2390 otoliths. The 1st annulus formation was detected comparing the progression by month of the smaller modal fish length with the respective otolith appearance during the year. Annuli were easily readable until the 5th ring, but in older fish the otoliths became thick and the annuli appeared very close to each other. The time of hyaline annual zone completion was estimated by the study of monthly marginal increments. This time was found to be around the end of the year and coincides with the prespawning period. Mean weight per age was studied during the year, showing that growth in weight was seasonal for adult fish and continuous for juveniles. Mean lengths at age from otolith reading in the monthly samples were applied to the yon Bertalanffy equation and growth parameters were estimated: L(inf) = 30.27 cm. k = 0.366, t(o) = -0.943. The same values of growth parameters were found fitting the growth equation to the back calculated fish lengths at age. By studying the growth curve it was observed that horse mackerel had fast growth during the first years of life. This seems to be a general characteristic of the most species in eastern Mediterranean.10aage10agrowth10aMediterranean10aotoliths10aPisces10aTrachurus trachurus1 aKarlou-Riga, C.1 aSinis, A. uhttps://icgf.myspecies.info/content/age-and-growth-horse-mackerel-trachurus-trachurus-l-gulf-saronikos-greece00518nas a2200121 4500008004100000245011100041210006900152300001200221490000900233653001600242100002000258856011800278 1995 eng d00aBiology and dynamics of the species of genus Trachurus (Pisces, Carandigae) in the Saronikos Gulf. 0 aBiology and dynamics of the species of genus iTrachurusi Pisces  a195-1970 v199510akape pisces1 aKarlou-Riga, C. uhttps://icgf.myspecies.info/content/biology-and-dynamics-species-genus-trachurus-pisces-carandigae-saronikos-gulf02149nas a2200193 4500008004100000245012000041210006900161260001200230300001000242490000700252520148200259653000801741653001101749653001301760653001101773653002801784100002001812856012301832 2000 eng d00aOtolith morphology and age and growth of Trachurus mediterraneus (Steindachner) in the Eastern Mediterranean0 aOtolith morphology and age and growth of iTrachurus mediterraneu c2000/// a69-820 v463 aOtolith morphology and age and growth of Mediterranean horse mackerel, Trachurus mediterraneus (Steindachner), in the Eastern Mediterranean (Gulf of Saronikos, Greece) were studied during the years 1989-1992. Length frequency of a total of 4612 specimens was followed by month; ages were determined based upon otolith microstructural interpretations (n = 1611). The otoliths were classified into four types on the basis of differences in the presence, number and appearance of pseudo-annuli in the first year of life. These seasonal rates of formation of pseudo-annuli and the true annuli were examined in samples collected monthly. Successive hyaline rings were interpreted as annuli on the basis of their formation at progressively greater distances from the nucleus, while the opaque rings were not always visible. The time of annulus completion was estimated by the study of monthly marginal increments. This time was found to be around the end of autumn and coincided with the end of the spawning period. The spawning period was identified by following the seasonal changes of gonadosomatic index. Different growth rates of otoliths for each otolith type may have been the result of differences in spawn-date. Mean lengths at age from otolith reading (all types combined) in the monthly samples were applied to the von Bertalanffy equation and growth parameters were estimated: L(inf) = 37.24 cm, k = 0.326, t0 = -0.842. (C) 2000 Elsevier Science B.V. All rights reserved.10aage10agrowth10aotoliths10aPisces10aTrachurus mediterraneus1 aKarlou-Riga, C. uhttps://icgf.myspecies.info/content/otolith-morphology-and-age-and-growth-trachurus-mediterraneus-steindachner-eastern02351nas a2200157 4500008004100000245013800041210006900179260001200248300001000260490000700270520173600277653001102013100002002024700002102044856012802065 1996 eng d00aOvarian atretic rates and sexual maturity of European horse mackerel, Trachurus trachurus (L.), in the Saronikos Gulf (Greece)0 aOvarian atretic rates and sexual maturity of European horse mack c1996/// a66-760 v943 aHistological sections of European horse mackerel, Trachurus trachurus (L.) ovaries were used to follow oogenesis and to describe the atretic states. Atretic states were used to examine the reproductive cycle during two successive reproductive seasons. During the first season, spawning lasted from December to May, with peak spawning occurring between the end of March and the beginning of April. The duration of the spawning season for the average female was estimated to be about 3 months. Atretic state 1 (yolked oocytes where <50% were in alpha (á) stage atresia) was the most common atretic condition during the spawning season. Atretic states 2 (yolked oocytes where ?50% were in á-stage atresia) and 3 (no yolked oocytes present but â atresia or later atresia stages) increased near the end of the season, and at the end of the season, females in atretic state 3 were predominant. The mean number of potential and past-spawning stages per female increased throughout the spawning season, indicating an increase in spawning frequency. During the second season, spawning occurred from January to May. High numbers of females in atretic states 2 and 3 were noted during the period considered to be the middle of the season, followed by an increase of females classified in atretic state 0 (yolked oocytes with no á-atresia stage), indicating a species flexibility to different conditions. The use of traditional macroscopic methods, such as gonadosomatic and hepatosomatic indices, revealed a conformity with the histological data concerning the identification of the spawning season. Total body lengths at female maturity (ML50), estimated histologically and macroscopically, were found to be 211 and 220 mm, respectively.10aPisces1 aKarlou-Riga, C.1 aEconomidis, P.S. uhttps://icgf.myspecies.info/content/ovarian-atretic-rates-and-sexual-maturity-european-horse-mackerel-trachurus-trachurus-l02458nas a2200289 4500008004100000245008700041210006900128260001300197300001000210490000700220520155800227653001101785653001701796653002701813653002101840100001601861700001401877700002001891700001401911700001501925700003201940700001901972700001501991700001402006700002002020856012802040 2003 eng d00aGrowth and reproduction of horse mackerel, Trachurus trachurus (Carangidae)0 aGrowth and reproduction of horse mackerel iTrachurus trachurus i bSpringer a27-610 v133 a

There is a broad knowledge of the growth and reproduction of Trachurus trachurus, although important gaps still exist. Horse mackerel are a long-lived species, reaching up to 40 years of age. They have isometric growth, although the alometric parameter b may vary throughout the year and in relation to latitude. Growth to age 3 is rapid compared to slower growth later in life. Phenomena of density dependent growth have been observed in the northeast Atlantic. Horse mackerel are an asynchronous species. The following stages of atresia have been validated in horse mackerel: alpha, beta, and delta. The transition in females from the spawning state to post spawning is very fast. The spawning fraction in horse mackerel is estimated to be between 8.3% and 20.9%. Horse mackerel have a long spawning season (up to 8 months), which varies according to geography. Length at first 28 maturity is between 16 and 25 cm, most commonly around 21 cm. Males mature at a slightly smaller length than females. The age at first maturity for females has been estimated to range from 2 to 4 years, depending on the geography. Batch fecundity has been estimated to range between 172–209 oocytes per gram-female-weight. Female spawning lasts between 65 and 94 days. An individual female can release from 5 to 16 batches during the spawning period. The estimated potential annual relative fecundity ranges from 1040 to 3280 oocytes per gram-female-weight.

10agrowth10areproduction10aαναπαραγωγή10aανάπτυξη1 aAbaunza, P.1 aGordo, L.1 aKarlou-Riga, C.1 aMurta, A.1 aEltink, A.1 aSantamaría, M., T. García1 aZimmermann, C.1 aHammer, C.1 aLucio, P.1 aIversen, S., A. uhttps://www.researchgate.net/publication/226117829_Growth_and_reproduction_of_horse_mackerel_Trachurus_trachurus_Carangidae