Автор неизвестен - Krmulture in iran - страница 12

Страницы:
1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53 

Fertility co-efficient (FC) was estimated according to the equation of Riedel (1969): FC = E/TL3, Where E = number of eggs produced and TL

= total length of female fish (mm). The regressions between fecundity (F) and total length (TL), body mass (M), and ovary mass (GW) were determined. All statistical analyses were carried out using SPSS 18.

Results

A total of 234 female specimens of Iranocichla hormuzensis were sampled. The ovarian mass ranged between 0.0035 g and 0.4782 g. (Mean + SD: 0.0350 + 0.0568 g). The gonadosomatic index (GSI) varied significantly in different months (ANOVA, df = 12 P = 0.000) (Fig. 1). The IG showed higher values (7.12 + 1.0206) from February to June with a peak in March, while the lower ones occurred from July to January. There was an increase in spawning intensity in early March to end of May and lasted until the early June.

The total number of ripe eggs in the ovary (absolute fecundity) ranged between 48-167 eggs with a Mean+SD of 107+35.2 for fish with total length range (TL) of 58-76 mm and a Mean+SD egg diameter of 1.92+0.73 mm (0.58-2.93 mm). Fecundity was better correlated with

total body mass (M) and total length (TL) (Table III). The Mean+SD of fertility co-efficient for this fish was 0.0003949 + 0.00009246. Fertility

co-efficient did no correlate with body mass and length, it showed the highest correlation with gonad mass (linear regression, r2 = 0.4105).

3

 

 

\lales Females

 

1 2

/\

 

 

/ \

 

i

/ \

 

J 1

0.5 -

/

 

 

—---~~~----^—~~~~

 

Months

Fig. 1. Monthly variations in the gonado-somatic index of I. hormuzensis.

Peak of the gonadosomatic index values occur in March and broods were present at the end of winter and beginning of spring and lasted to June. This suggests that most reproductive activities of I. hormuzensis in lower Mehran River occur from February to June. The breeding season for the Iranian cichlid was similar to that described by Esmaeili et al. (2008), but they found a strong breeding peak in May and we found the highest breeding peak in March. This difference in peak of GSI may be due to environmental factors such as water temperature and salinity and this could be related to the geographical and ecological differences between the two populations of I. hormuzensis in upper and lower Mehran River. Other indices such as Dobriyal index (DI), modified gonadosomatic index (MGSI) and reproductive condition (RC) showed a general increase in gonad investment and GSI from February to June.

The absolute fecundity ranged between 48-167 eggs (Mean+SD: 107+35.2 eggs) with an egg diameter range of 0.58 to 2.93 mm for fish of size range of 58-76 mm total length (TL). Esmaeili et al. (2008) reported the ranged of 38-151 eggs (Mean+SD: 99.8+33.8), from the upper Mehran River. They also noted that fecundity of I. hormuzensis is much lower than that given for some other mouth-brooding cichlids, e.g., 324-1672 in Oreochromis esculentus (Lowe-McConnell 1955), 56-489 in O. leucosticus (Welcomme 1967) and 309-1158 in O. niloticus (Rana 1988). Moyle & Cech (2000) mentioned that in mouth-brooding cichlids, the fecundity is considerably low because the parents assure the survival of the offspring, and in consequence, have less mortality. In the present study, fecundity was better correlated with total body mass than gonad mass and GSI as found in Oreochromis niloticus (Kariman & Salama 2008).

Acknowlegements

Special thanks to S. Sohrabi and V. Kiani for their help in the field and fish sampling and to N. Gilannejad, G. Sharifi, M. Yazdani, S. Kouhi, E. Paknahad, B. Tavakoli and S. Torabiyan for their help in laboratory. This study was financially supported by Isfahan University of Technology.

Batts, B.S. 1972. Sexual maturity, fecundity, and sex ratios of the Skipjack Tuna, Katsuwonus pelamis (Linnaeus), in North Carolina Waters. Trans Am Fish Soc., 101: 626-637.

Berra, T.M. 2001. Freshwater Fish Distribution. University Of Chicago Press, Chicago. 615 pp.

Coad, B.W. 1982. A new genus and species of cichlid endemic to southern Iran. Copeia. 1982: 28-37.

Dobriyal, A.K., Rautela, K.K., Rautela, A.S. 1999. Invention of a new index for the determination of sexual maturity in fishes. Uttar Pradesh J Zool. 19: 207-209.

Esmaeili, H.R., Ganjali, Z., Monsefi, M. 2008. Reproductive biology of the endemic Iranian cichlid, Iranocichla hormuzensis Coad, 1982 from Mehran River, southern Iran. Env. Biol. Fish. 84, 141-145.

Lowe-McConnell, R.H. 1955. Fecundity of Tilapia species. East Afr. Agric. For. J. 21:

45-52.

Moyle, P.B., Cech, J.J., 2000. Fishes: An Introduction to Ichthyology. Prentice Hall, New Jersey, USA. 621 pp.

Nelson, J.S. 2006. Fishes of the world. Wiley, New York. 624 pp.

Nikolsky, G.V. 1963. The ecology of fishes. Academic Press, New York. 472 pp.

Rana, K.J. 1988. Reproductive biology and the hatchery rearing of tilapia eggs and fry. In Recent advances in aquaculture. J. F. Muir, R. J. Roberts (Eds). Croom Helm,

London, pp. 343-406.

Riedel, D. 1968. Some remarks on the fecundity of Tilapia (T. mossambicus) and its introduction into middle Central America (Nicaragua) together with a contribution towards limnology of Nicaragua. Hydrobiologia, 25: 357-388.

Way, C.M., Burky, A.J., Harding, J.M., Hau, S., Puleloa, W.K.L.C. 1998. Reproductive biology of the endemic goby, Lentipes concolor, from Makamaka'ole Stream, Maui and Waikolu Stream, Molokai. Env. Biol. Fish., 51, 53-65.

Welcomme, R.L. 1967. The relationship between fecundity and fertility in the mouthbrooding cichlid fish Tilapia leucostica. J. Zool. Soc. Lond., 151: 453-468.

Cyts morphometry in three chilean Artemia franciscana (Kellog, 1906) strains under culture conditions

Patricio De los Rios Escalante

Escuela de Ciencias Ambientales, Facultad de Recursos Naturales, Universidad Cat6lica de Temuco, Casilla 15-D, Temuco, Chile. E-mail: patorios@msn.com / prios@uct.cl

Nucleo de Estudios Ambientales UC Temuco. Introduction

The brine shrimp Artemia in Chile is represented by the species A. franciscana (Kellog, 1906) and A. persimilis (Piccinelli & Prosdocimi, 1968), the first species is located in Andean saline lakes and coastal ponds in north of Chile, and central Chilean salt works, whereas the second species is located in two saline lakes in the extreme south of Chile (Gajardo et al., 2004; De los Rfos & Salgado, 2012). The use in aquaculture of Chilean Artemia strains are poorly studied, in spite of the advantages in the north of Chile for do an intensive brine shrimp culture (Zuniga & Wilson, 1996; De los Rfos & Salgado, 2012). The aim of the present study is a revision of published data about cyst morphometry of three Chilean A. franciscana populations under culture at out door environment (Zuniga & Wilson 1996).

Material and Methods

Data of cyst morphometry (capsulated and decapsulated cyst diameter, thickness cyst corion) and instar I lenght were obtained from three A. franciscana populations: Playa Yape (20°40' S; 70°15' W), Fundo Palo Colorado (31°50' S; 71°25'W), and Cejas Lagoon (23°20' S; 60°10'W), (Table 1). To the obtained data were applied a regression analysis for determine the existence of a potential relation between studied variables, the statistical analysis was done with the software Xlstat 5.0.

The results revealed the existence of a direct association between decapsulated diameter with capsultaded diameter and chorion thickness with capsulated diameter (P < 0.05), whereas it was not a significant association between thickness chorion and decapsulated diameter (Figure 1). Also it was denoted a significant regression between instar I lenght with thickness chorion and with capsulated diameter, whereas thickness chorion has not significant association with decapsulate diameter (Figure 1).

The results would denoted the existence of a marked population differntiation due probably to genetic isolation due geographical isolation and environmental heterogeneity of their habitats (Gajardo et al., 2004) that is expressed in morphological and other parameters such as individual growth under controlled conditions (De los Rfos, 2001) and extensive culture condicions (Zuniga & Wilson, 1996). The present study would agree with another topics for aquaculture advantages due that the presence of high thickness chorion can be a dissadvantage for aquaculture because the nauplius would spent more energy for hatch (Sorgeloos et al., 1986).

The direct relation observed between capsulated and decapsulated cyst diameter was found for Spanish Artemia populations (Amat, 1982). Although there are not studied with details, Zuniga et al., (1999) described a potential direct relation between capsulated and decapsulated cyst diameter for Chilean populations. Also, Amat (1982) and Zuniga et al., (1999) described that tropical populations has a thick chorion as protective strategy against solar natural ultraviolet exposure, but there are not associations between decapsulated cyst diameter and chorion thickness.

230:0 235,& 240,0 245,0 Captulaled diameter (urn)

I8'5'

I 7,5-

f(l) = 0,04k -0,75 = 0j

8 7>°~ O 225,0

230,0 235,0 240,0 245,0 Capsulated diameter (um)

■g 8,0

210,0     215,0     220,0     225,0 230,0 uncapMilnred diainetw ;uj.)

Hx) = 47,8x + 66,49 Rz = 0,75

7,5 8,0 Thickness chorion (um)

 

460 -,

=

450

 

440

 

430

=

420

-

410

 

400

 

390

210,0    215,0    220,0    225,0 230,0 Decapsulated cyst diameter (urn)

f(n)= l,84x -5,21

R? = 0,45

225       230       235 240 Capsulated diameter (um)

Figure 1. Regression analysis between cyst morphometry parameters for three Chilean A. franciscana populations (Cf: Zuniga & Wilson, 1996, page 54).

Table 1. Cyst morphometry parameters (Average + standard desviation) for three Chilean A. franciscana populations. (Cf: Zuniga & Wilson, 1996, pag 54).

Site

Salinity

Capsulated

diameter (um)

Decapsulated

diameter (um)

Chorion

thickness (um)

Instar I Lenght (um)

Fundo Palo Colorado

Wild

environment

226.7 + 10.5

211.9 + 12.4

7.4

417.5 + 25.2

Cejas lagoon

Wild

environment

241.2 + 9.1

225.0 + 10.2

8.1

451.7 + 23.3

Playa Yape

Wild

environment

236.9 + 8.8

221.8 + 12.7

7.3

415.2 + 26.1

Fundo Palo Colorado

 

35

228.0 + 9.5

213.3 + 6.6

7.3

421.7 + 32.4

Cejas lagoon

 

35

242.1 +'7.7

226.5 + 13.4

7.9

445.7 + 27.3

Playa Yape

 

35

237.2 + 6.9

222.1 + 8.8

7.6

411.5 + 28.1

Fundo Palo Colorado

 

90

230.0 + 6.9

215.5 + 6.5

7.4

419.3 + 18.6

Cejas lagoon

 

90

242.5 + 7.7

224.7 + 3.4

7.8

452.1 + 19.9

Playa Yape

 

90

237.3 + 9.5

228.8 + 8.8

7.3

418.6 + 14.7

Amat, F. 1982. Diferenciaci6n y distribuci6n de las poblaciones de Artemia (Crustaceo, Branchiopodo) de Espana. II. Incidencia de la salinidad ambiental sobre la morfologfa y desarrollo. Investigaciones Pesqueras 44: 485-503.

De los Rfos-Escalante, P. & I. Salgado, 2012. Artemia (Crustacea, Anostraca) in Chile: a review of basic and applied biology. Latin American Journal of Aquatic

Research, 40: 487-496.

De los Rfos, P. 2001. Crecimiento en poblaciones de Artemia franciscana y Artemia persimilis (Crustacea, Anostraca) en condiciones controladas. Revista de Biologfa Tropical 49: 629-634. Gajardo, G., J.. Crespo, A. Triantaphyllidis, A. Tzika, A.D. Baxenavis, I. Kappas & T.J. Sorgeloos, 2004. Species identification on Chilean brine shrimp Artemia populations based on mitochondrial

DNA RFLP analysis. Journal of Biogeography 31: 547-555.

Sorgeloos, P., P. Lavens, P. Leger, W. Tackaert & D. Versichele, 1986. Manual for the culture and use of the brine-shrimp Artemia in aquaculture. Belgian Administration for Development Cooperation; The Food and Agricultural Organization of the United Nations Organization, State University of Ghent, Faculty of Agriculture, Belgium, 319 p.

Zuniga, O. & R. Wilson, 1996. Variabilidad interpoblacional de Artemia franciscana cultivadas bajo condiciones estandar: biometrfa, parametros reproductivos y perfil de acidos grados. Estudios Oceanol6gicos 15: 51-60. [In Spanish with English abstract]

Zuniga, O., R. Wilson, F. Amat & F. Hontoria, 1999. Distribution and characterization of Chilean brine shrimp Artemia (Crustacea, Branchiopoda, Anostraca). International Journal of Salt Lake Research 8: 23-40

Faizbakhsh, R.1, Gheshlaghi, P.2

1Ph.D., Fisheries and Aquaculture Economics, 2M.Sc. Fisheries and Aquaculture Reza faiz@yahoo.com

Abstract

This research was to investigate the effects of different environmental factors on fish larvae; the gold fish will be measured. In this regard, the first 100 pieces larval fish in an aquarium gold fish placed in three experimental treatments are 300 pieces measured in three aquaria. The effects of different environmental factors on the larvae examined the effects observed in this particular domain is registered. Impact of this measure will be evaluated using mathematical matrices. The definitions can be realized to evaluate the defined are range between + 2 and -2. According to this definition, all results can is include +2, +1, 0, - 1, -2. In table 1, a total of 3 to 6 chemical physicochemical treatments have been studied in which the effects of physical factors such as temperature, oxygen, turbidity and acidity ionization has been studied. Weather conditions such as light, wind, rain, etc. Table 2 can have negative effects on larval growth unless these conditions are controlled and limited. In the circumstances mentioned in table 3 the water depth of the pond building, pond pain, ponds and water color etc are all examined. In table 4 the concentration of larvae and other similar factors are considered. Table 5 other factors such as phytoplankton, zooplankton and larval predators and competitors for feed pathogens will be studied. To reduce the mortality of larvae during development is required to comply with all the points on the basis of criteria defined to minimize

losses. Aquarium management larvae reared larvae must have sufficient information to enable management to take action in this regard, with better management. Larvae reared larvae are directly related to the economic survival of the larvae to face losses can cause losses for manufacturers to make gold fish larvae. The loss of the main tasks is breeders. Keyword

Gold fish, Measurements, Feeding, Larvae, Multi factors, Larvae growth

Introduction

The goldfish (Carassius auratus auratus) is a freshwater fish in the family Cyprinidae of order Cypriniformes. It was one of the earliest fish to be domesticated, and is one of the most commonly kept aquarium fish. A relatively small member of the carp family (which also includes the koi carp and the crucian carp), the goldfish is a domesticated version of a less-colorful carp (Carassius auratus) native to East Asia. It was first domesticated in China more than a thousand years ago, and several distinct breeds have since been developed. Goldfish breeds vary greatly in size, body shape, fin configuration and coloration (various combinations of white, yellow, orange, red, brown, and black are known). A goldfish measuring 16 inches (41 cm) and 5 pounds (2.3 kg) was caught in a pond in England, thought to have been abandoned there after outgrowing a tank. In frosty climes the depth should be at least 80 centimeters (31 in) to preclude freezing. Temperatures under about 10 °C (50 °F) are dangerous to fancy varieties, though commons and comets can survive slightly lower temperatures. Extremely high temperatures (over 30 °C (86 °F) can also harm goldfish. Goldfish are popular pond fish, since they are small, inexpensive, colorful and very hardy. In an outdoor pond or water garden, they may even survive for brief periods if ice forms on the surface, as long as there is enough oxygen remaining in the water and the pond does not freeze solid. Goldfish may only grow to

sexual maturity with enough water and the right nutrition. Most goldfish breed in captivity, particularly in pond settings. Breeding usually happens after a significant temperature change, often in spring. Males chase gravid female goldfish (females carrying eggs), and prompt them to release their eggs by bumping and nudging them.

Goldfish, like all cyprinids, are egg-layers. Their eggs are adhesive and attach to aquatic vegetation, typically dense plants such as Cabomba or Elodea or a spawning mop. The eggs hatch within 48 to 72 hours.

Within a week or so, the fry begins to assume its final shape, although a year may pass before they develop a mature goldfish color; until then they are a metallic brown like their wild ancestors. In their first weeks of life, the fry grow quickly an adaptation born of the high risk of getting devoured by the adult goldfish (or other fish and insects) in their environment.

Data collection

Comparison of methods to collect information through the use is feed goldfish on fish and aquariums and laboratory environments.

Material and Methods

This research was to investigate the effects of different environmental factors on fish larvae, the goldfish will be measured. In this regard, the first 100 pieces larval fish in an aquarium goldfish placed in three experimental treatments are 300 pieces measured in three aquariums. The effects of different environmental factors on the larvae examined the effects observed in this particular domain is registered. Impact of this measure will be evaluated using mathematical matrices. The definitions can be realized to evaluate the defined are range between +2 and -2, According to this definition, all results can is include +2, +1, 0 ,-1 , -2. Therefore, the assessment of the environmental impacts of various factors on the scope and range of numbers and ratings are visible. As noted above, all effects on larval fish goldfish physical observation and then using the evaluation matrix.

The test method can be noted that several factors examined, which can be seen in the following tables. Indeed, all evaluation factors on larval fish are goldfish. This method is based (Kestemont and Baras , 2001) on the method known as the method of measuring the effects on fish larvae. In Table 1, all Phisico-chemistry factors are considered influential. Initial feeding of larvae (application of suitable feed) is important stage is larvae culture and in transition feeding to external feeding for important of this stage in named critical period. Early life stages of development are some of the most important phase of fish development.

Table 1. Phisico-chemistry documents evaluation for gold fish

Row     documents evaluation    Treatment 1     Treatment 2      Treatment 3

1 Phisico-chemistry

-

-

-

2 Temperature

+2

+2

+1

3 Oxygen

+2

+1

+2

4 Turbidity

-2

-2

-1

5 pH

+1

+1

+1

6 Ions

-2

-1

-2

* Total

+1

+1

-1

Table 2 Factors affecting the kidney has been weather tested. The

assessment of these factors has been studied on three larval treatments.

Light winds  and rainfall

effects on

larval fish

goldfish each

experimentally measured.

 

 

 

Table 2: Weather documents evaluation for gold fish

 

 

Row    documents evaluation

Treatment 1

Treatment 2

Treatment 3

1 Weather

-

-

-

2 Light

+1

+1

+2

3 Wind

-2

-1

-2

4 Rain

-1

-2

-1

5 Total

-2

-2

-1

In table 3, all factors that can affect the environment of the tank or aquarium are located on the larvae. Factors such as depth, shape, color and materials used in the tanks each have an effect on the larvae examined.

Table 3: Tank environmental documents evaluation for gold fish

Row

documents evaluation

Treatment 1

Treatment 2

Treatment 3

1

Tank Environmental

-

-

-

2

Water depth

+2

+1

+1

3

Tank shape

+2

+2

+1

4

Tank color

+ 1

+2

+1

5

Structure

+ 1

+2

+1

6

Water velocity

+ 1

+1

+1

*

Total

+7

+8

+5

Table 4 has the effect of crowding and other factors considered. These factors influence the rate determined by the scale of the matrix has been studied mathematically.

Table 4: documents evaluation for gold fish

Row

documents evaluation

Treatment 1

Treatment 2

Treatment 3

1

Conspecifics

-

-

-

2

Density

-2

-1

-2

3

Hierarchy

-1

0

0

4

Total

-3

-1

-2

In Table 5, all biological factors that can have influence on larval goldfish have been studied. Most of these issues are important indicators that are of utmost importance. According to the method of indexing the effects of these factors on the development of a mathematical matrix has been studied. Negative numbers are the indicators that the shock or dying larvae negative scores and indicators the opposite effect on growth has been able to get a positive score.

Table 5: Biotic documents evaluation for gold fish

Row

documents evaluation

Treatment 1

Treatment 2

Treatment 3

1

Biotic

-

-

-

2

Phytoplankton

+2

+1

+1

3

Zooplankton

+1

+1

+1

4

Competitors

+1

+1

+1

5

Predators

-2

-2

-2

6

Pathogens

-2

-2

-2

*

Страницы:
1  2  3  4  5  6  7  8  9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53 


Похожие статьи

Автор неизвестен - 13 самых важных уроков библии

Автор неизвестен - Беседы на книгу бытие

Автор неизвестен - Беседы на шестоднев

Автор неизвестен - Богословие

Автор неизвестен - Божественность христа