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Full-Text Articles in Life Sciences

Some Histological Reveals On Reproduction Of One Of The Lessepsian Species, Nemipterus Randalli In Antalya (Turkey), Mehmet Rüştü Özen Jan 2021

Some Histological Reveals On Reproduction Of One Of The Lessepsian Species, Nemipterus Randalli In Antalya (Turkey), Mehmet Rüştü Özen

Turkish Journal of Veterinary & Animal Sciences

In this study, the reproduction of Nemipterus randalli, one of the lessepsian fish catch from the Gulf of Antalya, Turkey was interpreted histologically. Regarding the fish used in this study (N = 1715), it is noteworthy to mention that male individuals are larger than females. The first sexual maturity in males was determined 17 cm TL and 60 g in BW, whereas 13 cm TL and 25 g BW in females. Females reached sexual maturity at age I+ and males at the age of II+. Seven different stages (O1-O7) were identified in oocyte maturation in the ovaries. The spawning time …


Surgical Sterilization Impacts On Behavior Of Coyote Pairs, Tyler Leary, Jeffrey T. Schultz, Julie K. Young Jan 2021

Surgical Sterilization Impacts On Behavior Of Coyote Pairs, Tyler Leary, Jeffrey T. Schultz, Julie K. Young

USDA Wildlife Services: Staff Publications

Coyotes (Canis latrans) involved in depredation of livestock, an act frequently resulting in human-wildlife conflict, often do so out of necessity for provisioning pups. Surgical sterilization methods such as vasectomy that preserve gonadal hormones have been successful in reducing depredation by free-ranging coyotes while allowing individuals to maintain territoriality and mate fidelity. However, use of these methods remain costly and ineffective for wide-scale use. Given the alternative proposal of using chemical sterilization techniques, we investigated whether the use of hormone-altering sterilization methods impacted behavior of captive coyote pairs (i.e., male-female pair bonds). Our objective was to evaluate behavior …


Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French Jan 2021

Measuring Adrenal And Reproductive Hormones In Hair From Southern Beaufort Sea Polar Bears (Ursus Maritimus), Marilize Van Der Walt, Lorin A. Neuman-Lee, Patricia A. Terletzky, Todd C. Atwood, Eric M. Gese, Susannah S. French

USDA Wildlife Services: Staff Publications

Polar bears (Ursus maritimus) use sea ice to access marine mammal prey. In Alaska’s Southern Beaufort Sea, the declining availability of sea ice habitat in summer and fall has reduced opportunities for polar bears to routinely hunt on the ice for seals, their primary prey. This reduced access to prey may result in physiological stress with subsequent potential consequences to reproductive function (physiological changes that accompany reproduction), which can be measured via reproductive hormones. Hormone concentrations in hair can be used as a minimally invasive alternative to serum concentrations, which must come from animal captures. Hair samples also …


Reproductive Trade-Offs In The Colorado Checkered Whiptail Lizard (Aspidoscelis Neotesselatus): An Examination Of The Relationship Between Clutch And Follicle Size, Hannah E. Caracalas, S. S. French, S. B. Hudson, B. M. Kluever, A. C. Webb, D. Eifler, A. J. Lehmicke, Lise M. Aubry Jan 2021

Reproductive Trade-Offs In The Colorado Checkered Whiptail Lizard (Aspidoscelis Neotesselatus): An Examination Of The Relationship Between Clutch And Follicle Size, Hannah E. Caracalas, S. S. French, S. B. Hudson, B. M. Kluever, A. C. Webb, D. Eifler, A. J. Lehmicke, Lise M. Aubry

USDA Wildlife Services: Staff Publications

Life history theory predicts that there should be an inverse relationship between offspring size and number, because individuals cannot simultaneously maximize both when resources are limited. Although extensively studied in avian species, the occurrence and determinants of reproductive tradeoffs in oviparous reptiles are far less understood, particularly in parthenogenetic species. We studied this trade-off in the Colorado Checkered Whiptail, Aspidoscelis neotesselatus, a female-only parthenogenetic lizard. Using data previously collected in 2018 and 2019, we tested for clutch and egg size trade-offs and determined whether this relationship could be influenced by female size and aspects of physiological condition. Physiological condition …


Associations Among Beef Cattle Genotypes, Neospora Caninum Infection, And Reproductive Performance, Ryan James Page May 2020

Associations Among Beef Cattle Genotypes, Neospora Caninum Infection, And Reproductive Performance, Ryan James Page

Graduate Theses and Dissertations

Reproductive performance is crucial for sustained financial success in the beef cattle industry. This dissertation includes a population study that quantified the incidence of Neospora caninum infections in the central region of the United States and tested its relationship with reproductive performance in beef cattle. Trial one of that study concluded that 6.9% of open, replacement heifers (n = 1306) tested seropositive. The second trial in that project found that 9.6% of the breeding age females (n = 500) tested were seropositive for Neospora caninum; and that state in which the cattle lived and age impacted (P < 0.05) infection rate. Breed composition, number of farm dogs on the ranch, and use of total mixed rations were not associated (P > 0.1) with seropositive …


Competing Reproductive And Physiological Investments In An All‑Female Lizard, The Colorado Checkered Whiptail, Lise M. Aubry, Spencer B. Hudson, Bryan M. Kluever, Alison C. Webb, Susannah S. French Jan 2020

Competing Reproductive And Physiological Investments In An All‑Female Lizard, The Colorado Checkered Whiptail, Lise M. Aubry, Spencer B. Hudson, Bryan M. Kluever, Alison C. Webb, Susannah S. French

USDA Wildlife Services: Staff Publications

Organisms in the wild have to allocate limited resources towards competing functions such as reproduction, growth, and self-maintenance. These competing investments create significant changes in physiological activity, and we still know little about the relationship between physiological activity and reproductive investment in natura. We investigated trade-offs between physiological activity and reproductive investment in the parthenogenetic Colorado checkered whiptail, Aspidoscelis neotesselata, across three different sites at the US Army Fort Carson Military Installation near Colorado Springs, CO, through-out the reproductive season in 2018 and 2019. We measured clutch size and reproductive activity and quantified plasma corticosterone (CORT), reactive oxygen metabolites (ROMs), …


The Use Of Doppler Ultrasound As A Potential Fertility Predictor In Male Goats, Diego Luiz Dos Santos Ribeiro, Larissa Sarmento Santos, Itamara Gomes França, Hellyda Gomes Pereira, Joaquim De Sousa Lima, Bento Douglas Brito Miranda, Alcina Vieira Carvalho Neta, Jose Ribamar S Torres Junior Jan 2020

The Use Of Doppler Ultrasound As A Potential Fertility Predictor In Male Goats, Diego Luiz Dos Santos Ribeiro, Larissa Sarmento Santos, Itamara Gomes França, Hellyda Gomes Pereira, Joaquim De Sousa Lima, Bento Douglas Brito Miranda, Alcina Vieira Carvalho Neta, Jose Ribamar S Torres Junior

Turkish Journal of Veterinary & Animal Sciences

The aim of the current study is to correlate Doppler flowmetry with andrological features in male goats belonging to different age and fertility groups. Thirty native crossbreed bucks bred in Northeastern Brazil were subjected to B-mode, spectral and color Doppler ultrasound, as well as to andrological examinations. Color Doppler ultrasound was used to evaluate blood flow in the pampiniform plexus and testicular parenchyma. Semen was collected through the electroejaculation method in order to have its physical and morphological features evaluated. The animals were grouped based on age (young, mature, and old) and fertility level (high and low) before analysis. Data …


In Vitro Exposure To Di-(2-Ethylhexyl) Phthalate (Dehp) Stimulates Spontaneous Felineuterine Contractions, Ruhi̇ Kabakçi, Hasan Ceyhun Macun, Ebru Yildirim, İbrahi̇m Mert Polat, Taha Burak Eli̇foğlu Jan 2020

In Vitro Exposure To Di-(2-Ethylhexyl) Phthalate (Dehp) Stimulates Spontaneous Felineuterine Contractions, Ruhi̇ Kabakçi, Hasan Ceyhun Macun, Ebru Yildirim, İbrahi̇m Mert Polat, Taha Burak Eli̇foğlu

Turkish Journal of Veterinary & Animal Sciences

Di-(2-ethylhexyl) phthalate (DEHP) is widely used as a plasticizer in various products such as PVC-derived plastics, toys, packaging materials, cosmetics, and pharmaceuticals. This study aimed to investigate the effect of DEHP on spontaneous contractions of the feline uterus in vitro. Tubal 1-cm uterine samples prepared from 10, 9, and 12 uteri obtained from adult cats in estrus (n = 5), diestrus (n = 5), and interestrus (n = 5), respectively, after ovariohysterectomy were suspended in an isolated organ bath in aerated Krebs solution at 39 ± 1 °C, and an initial 1 g tension was given. After 1 h equilibration …


Improving Techniques To Study Equine Cervical Mucociliary Clearance, Melissa A. Hawkes May 2018

Improving Techniques To Study Equine Cervical Mucociliary Clearance, Melissa A. Hawkes

Electronic Theses and Dissertations

Bacterial uterine infections inflict major losses on the equine breeding industry. These infections usually arise from bacteria introduced at breeding. Micro-currents propelled by ciliated cells between the folds of the uterus and cervix have been proposed as a means by which contaminants are expelled. Previous data have shown possible ciliary micro-currents propelling carbon particles, occasionally rotating, through cervical folds. However, adherence to the epithelium may have interfered with movement of carbon in these studies. Therefore, we tested potentially non-adherent substances to reveal ciliary micro-currents on the equine cervix under high magnification video-endoscopy. We hypothesized that polyethylene green microspheres 1 - …


Follicular Dynamics In Insulin Resistant Mares, Julio Cesar Prado Dec 2016

Follicular Dynamics In Insulin Resistant Mares, Julio Cesar Prado

Masters Theses

Obesity and insulin resistance have been linked to prolonged interovulatory period, aberrations in the estrous cycle, and continuous reproductive activity during the non-breeding season. EMS has been determined to influence the intrafollicular environment of mare ovaries. In humans, insulin resistance has been linked to polycystic ovaries as part of Polycystic Ovarian Syndrome (PCOS). A study was conducted to determine 1) the impact of insulin resistance on follicle growth and size at ovulation, and 2) whether predicted ovulatory follicles respond to hCG administration in Insulin-resistant (IR) mares. Mares were selected for the study based on insulin sensitivity and separated into an …


In Vivo Embryo Production In Some Native Goat Breeds In Turkey, Ali̇ Reha Ağaoğlu, Kübra Karakaş, Mustafa Kaymaz Jan 2014

In Vivo Embryo Production In Some Native Goat Breeds In Turkey, Ali̇ Reha Ağaoğlu, Kübra Karakaş, Mustafa Kaymaz

Turkish Journal of Veterinary & Animal Sciences

The aim of this study was to assess the efficacy of the repeated administration of superovulatory protocol and surgical procedure in in vivo embryo production, as well as to determine the differences in the responses to superovulatory treatment among several Turkish native goat breeds (Angora, Kilis, Honamli, Hair, and Norduz). A superovulatory treatment procedure was repeated 3 times in this study. The estrus cycles were synchronized and superovulatory response was induced with porcine follicle-stimulating hormone during the natural breeding season. Natural mating was performed following CIDR removal. Embryo recovery was performed surgically on day 6, after the first mating. According …


Stress And Reproductive Hormones In Grizzly Bears Reflect Nutritional Benefits And Social Consequences Of A Salmon Foraging Niche, Heather M. Bryan, Chris T. Darimont, Paul C. Paquet, Katherine E. Wynne-Edwards, Judit E. G. Smits Nov 2013

Stress And Reproductive Hormones In Grizzly Bears Reflect Nutritional Benefits And Social Consequences Of A Salmon Foraging Niche, Heather M. Bryan, Chris T. Darimont, Paul C. Paquet, Katherine E. Wynne-Edwards, Judit E. G. Smits

Physiology Collection

Physiological indicators of social and nutritional stress can provide insight into the responses of species to changes in food availability. In coastal British Columbia, Canada, grizzly bears evolved with spawning salmon as an abundant but spatially and temporally constrained food source. Recent and dramatic declines in salmon might have negative consequences on bear health and ultimately fitness. To examine broadly the chronic endocrine effects of a salmon niche, we compared cortisol, progesterone, and testosterone levels in hair from salmon-eating bears from coastal BC (n = 75) with the levels in a reference population from interior BC lacking access to salmon …


General Reproductive Properties In Pigs, İrfan Tur Jan 2013

General Reproductive Properties In Pigs, İrfan Tur

Turkish Journal of Veterinary & Animal Sciences

Pig breeding is usually undertaken for fat and meat production, but different sectors (cosmetics industry, pharmaceutical industry, medical sector, etc.) can also use pigs for alternate purposes. Pork is evaluated based on the status of an amended law regarding butchers' meat in Turkey. There have been 25 pig farms registered in Turkey since 7 July 2006 in the framework of compliance with the European Union. On average, a sow has 2.3 farrowings per year, producing 9.5 to 12.5 piglets per litter. It is important that high proportions of selected replacement gilts reach puberty at an early age in order to …


The Effect Of Selenized Yeast Supplementation On Some Performance Parameters In Sheep, Bogumila Pilarczyk, Agnieszka Tomza-Marciniak, Zbigniew Dobrzanski, Malgorzata Szewczuk, Tomasz Stankiewicz, Dariusz Gaczarzewicz, Wlodzimierz Lachowski Jan 2013

The Effect Of Selenized Yeast Supplementation On Some Performance Parameters In Sheep, Bogumila Pilarczyk, Agnieszka Tomza-Marciniak, Zbigniew Dobrzanski, Malgorzata Szewczuk, Tomasz Stankiewicz, Dariusz Gaczarzewicz, Wlodzimierz Lachowski

Turkish Journal of Veterinary & Animal Sciences

The aim of this study was to determine the levels of serum selenium in coarse-haired Pomeranian sheep and to evaluate the effect of the oral supplementation of selenized yeast on selected performance parameters in such sheep. The sheep were divided into 2 groups, with 53 ewes forming the experimental group and 34 ewes forming the control group. The concentration of serum selenium in all 87 sheep from the 2 groups was analyzed. The sheep in the experimental group received selenized yeast for the 3 days before and 3 days after mating (1 g preparation/animal daily, with 1 g of preparation …


Evaluation Of The Possibility Of Using Oligosaccharide-Free Pea In Japanese Quail Nutrition, Danuta Szczerbinska, Zofia Tarasewicz, Piotr Gulewicz, Danuta Majewska, Marek Ligocki Jan 2012

Evaluation Of The Possibility Of Using Oligosaccharide-Free Pea In Japanese Quail Nutrition, Danuta Szczerbinska, Zofia Tarasewicz, Piotr Gulewicz, Danuta Majewska, Marek Ligocki

Turkish Journal of Veterinary & Animal Sciences

In this paper, evaluation of the effect of processed pea seeds (free of raffinose family oligosaccharides) on the performance traits and the results of reproduction in Japanese quails is presented. A flock of 72 quails was divided into 3 groups consisting of equal numbers of birds (18 females and 6 males). Birds were kept in cages in an environmentally controlled room with a lighting cycle of 17 h of light and 7 h of dark, and they were fed 1 of 3 different diets. Whereas diet 1 served as the control, diet 2 was supplemented with 5% and diet 3 …


Associations Between Ghr And Igf-1 Gene Polymorphisms, And Reproductive Traits In Wenchang Chickens, Hui Fang Li, Wen Qi Zhu, Kuan Wei Chen, Xu Wu, Qing Ping Tang, Yu Shi Gao Jan 2008

Associations Between Ghr And Igf-1 Gene Polymorphisms, And Reproductive Traits In Wenchang Chickens, Hui Fang Li, Wen Qi Zhu, Kuan Wei Chen, Xu Wu, Qing Ping Tang, Yu Shi Gao

Turkish Journal of Veterinary & Animal Sciences

Alleles of physiological candidate genes for reproductive traits, insulin-like growth factor-1 (IGF-1), and growth hormone receptor (GHR) were assessed to determine their associations with total egg production (NE), average days of continual egg-laying (ADCE), and number of double yolk eggs (DYE) in Wenchang chickens (Chinese indigenous breed). PCR-RFLP was used for genotype identification. The frequency of restriction enzyme C1/C2 alleles in the population was 0.53 (C1) and 0.47 (C2) for IGF-1. For GHR-intron 2 it was 0.06 and 0.94 for (A1) and (A2), respectively, while for GHR-intron 5 it was 0.20 (B1) and 0.80 (B2). Four significant associations were found …


Sheep Updates 2007 - Part 4, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence, David Masters, R. Silberstein, F. Byrne, P. G. H. Nichols, J. Young, L. Aitkins, M. G. Wilmot, A. J. Rintoul, T. Lambert, D. R. Mcclements, P. Raper, P. Ward, C. Walton, T. York, David Pethick, David Hopkins, Malcolm Mcphee, D. B. Savage, J. V. Nolan, I. R. Godwin, A. Aoetpah, T. Nguyen, N. Baillie, C. Lawler, Ken Geenty, John Smith, Darryl Smith, Tim Dyall, Grant Uphill, John Young, Michael Paton, John Dorrian Jul 2007

Sheep Updates 2007 - Part 4, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence, David Masters, R. Silberstein, F. Byrne, P. G. H. Nichols, J. Young, L. Aitkins, M. G. Wilmot, A. J. Rintoul, T. Lambert, D. R. Mcclements, P. Raper, P. Ward, C. Walton, T. York, David Pethick, David Hopkins, Malcolm Mcphee, D. B. Savage, J. V. Nolan, I. R. Godwin, A. Aoetpah, T. Nguyen, N. Baillie, C. Lawler, Ken Geenty, John Smith, Darryl Smith, Tim Dyall, Grant Uphill, John Young, Michael Paton, John Dorrian

Sheep Updates

This session covers eight papers from different authors:

GRAZING

1. The impact of high dietary salt and its implications for the management of livestock grazing saline land, Dean Thomas, Dominique Blache, Dean Revell, Hayley Norman, Phil Vercoe, Zoey Durmic, Serina Digby, Di Mayberry, Megan Chadwick, Martin Sillence and David Masters, CRC for Plant-based Management of Dryland Salinity, Faculty of Natural & Agricultural Sciences, The University of Western Australia, WA.

2. Sustainable Grazing on Saline Lands - outcomes from the WA1 research project, H.C. Norman1,2, D.G. Masters1,2, R. Silberstein1,2, F. Byrne2,3, P.G.H. Nichols …


The Influence Of Shearing On Reproduction In Angora Rabbits, Tayfur Bekyürek, Mustafa Ün, Orkun Demi̇ral Jan 2005

The Influence Of Shearing On Reproduction In Angora Rabbits, Tayfur Bekyürek, Mustafa Ün, Orkun Demi̇ral

Turkish Journal of Veterinary & Animal Sciences

The aim of this study was to determine the optimum time and the conditions of mating for Angora rabbits. The study was initiated with 60 French Angora rabbits (53 does and 7 bucks). All animals were kept in individual cages under the same environmental conditions. The does were divided into 6 groups: does in group 1 were mated a week before the shearing, does in group 2 were mated during the shearing period, does in group 3 were mated a week after shearing, does in group 4 were mated a month after shearing and does in group 5 were mated …


Some Biological Characteristics Of The Tub Gurnard, Chelidonichthys Lucernus (Linnaeus, 1758) In The Sea Of Marmara, Lütfi̇ye Eryilmaz, Nuretti̇n Meri̇ç Jan 2005

Some Biological Characteristics Of The Tub Gurnard, Chelidonichthys Lucernus (Linnaeus, 1758) In The Sea Of Marmara, Lütfi̇ye Eryilmaz, Nuretti̇n Meri̇ç

Turkish Journal of Veterinary & Animal Sciences

The biology of the tub gurnard, Chelidonichthys lucernus (Linnaeus, 1758), has been studied on data collected between November 1996 and November 1997 from the Sea of Marmara. Totally, 224 tub gurnards were sampled. The age, growth, length-weight relationship, condition factor, male to female ratio, first sexual maturity age, length and reproduction period were examined. The age composition of samples ranged between 1 and 6 years. Total length ranged between 12.3 and 41.5 cm, while weight varied from 15 to 617 g. The total length-weight relationship was estimated as W=0.0092L^{3.019}. The parameters of the von Bertalanffy growth equation were: L_{\infity} = …


Determination Of The Recruitment To Stock And Reproduction Period For Flounder (Platichthys Flesus Luscus Pallas, 1811) Along The Trabzon-Rize Coast, Eastern Black Sea, Erhan Çi̇loğlu Jan 2005

Determination Of The Recruitment To Stock And Reproduction Period For Flounder (Platichthys Flesus Luscus Pallas, 1811) Along The Trabzon-Rize Coast, Eastern Black Sea, Erhan Çi̇loğlu

Turkish Journal of Veterinary & Animal Sciences

The length and weight distribution of flounder (Platichthys flesus luscus Pallas, 1811) were 14.2-34.1 cm and 28.879-611.0 g, respectively. The samples were distributed between the 0 and VII age groups. Von Bertalanffy growth parameters for flounder were L_t = 41.241[1-e^{-0.161(t+3.240)}] for females, L_t= 33.567[1-e^{-0.181(t+3.525)}] for males and L_t = 40.577[1-e^{-0.142(t+3.105)}] for the sexes combined. Reproduction took place from December to March but peaked in December. Two recruitment periods were determined for flounder: the first was January to July, and the second August to November. The proportions of recruitment in the first and second periods were 68.13% and 31.87%, respectively.


Some Productive Characteristics Of F_1, B_1 And F_{1}Xb_{1} Crossbreeds From Simmental X Sar Crossbreeding, Mehmet N. Orman, Okan Ertuğrul, Orhan Alpan Jan 2005

Some Productive Characteristics Of F_1, B_1 And F_{1}Xb_{1} Crossbreeds From Simmental X Sar Crossbreeding, Mehmet N. Orman, Okan Ertuğrul, Orhan Alpan

Turkish Journal of Veterinary & Animal Sciences

South Anatolian Red (SAR) cattle are well adapted to the arid, hot and harsh conditions of the region and have the highest milk yield among the local breeds in Turkey. The purpose of this study was to determine the main productive characteristics, such as viability, reproduction and milk production, of F_1, B_1 and F_{1}XB_{1} crossbred genotype groups from Simmental x SAR crossbreeding. A t test was used for 2 group comparisons. In cases of insufficient numbers of variants in the groups Kruskal-Wallis and Mann-Whitney U tests were used where appropriate. There was no difficulty during birth in any of the …


Effect Of Certain Factors On Productive And Reproductive Efficiency Traits And Phenotypic Relationships Among These Traits And Repeatabilities In West Anatolian Holsteins, Mustafa Tekerli̇, Mustafa Gündoğan Jan 2005

Effect Of Certain Factors On Productive And Reproductive Efficiency Traits And Phenotypic Relationships Among These Traits And Repeatabilities In West Anatolian Holsteins, Mustafa Tekerli̇, Mustafa Gündoğan

Turkish Journal of Veterinary & Animal Sciences

The present investigation was undertaken to study certain factors affecting production efficiency, milk production and reproduction and to estimate the repeatabilities and phenotypic correlations of these traits in Holsteins maintained at different farms in western Anatolia over 3 years (1990 - 1993). The data consisted of 506 first and 232 second lactations of 525 cows. Three production efficiency traits (milk yield per day of lactation length (MYPDLL), milk yield per day of calving interval (MYPDCI) and milk yield per day of age at second calving (MYPDASC)), one production trait (lactation yield (LY)), and one reproduction trait (calving interval (CI)) were …


Reproductive Biology In A Native European Catfish, Silurus Glanis L., 1758, Population In Menzelet Reservoir, Ahmet Alp, Cemi̇l Kara, Hakan Murat Büyükçapar Jan 2004

Reproductive Biology In A Native European Catfish, Silurus Glanis L., 1758, Population In Menzelet Reservoir, Ahmet Alp, Cemi̇l Kara, Hakan Murat Büyükçapar

Turkish Journal of Veterinary & Animal Sciences

The reproductive activities of Silurus glanis were investigated over 12 months in Menzelet Reservoir, in the East Mediterranean region of Turkey. Total length of the examined 245 S. glanis varied from 33.4 cm (220 g) to 195.0 cm (48,000 g), and age distribution ranged between 1 and 14. Observations on the seasonal distribution of the maturity stages and variations in the gonadosomatic index (GSI) confirmed that Silurus glanis has a prolonged spawning period extending from the beginning of June to August. The males mature earlier than the females, at a minimum size of 78.82 cm in total length and at …


Age, Growth And Reproduction Of Tub Gurnard (Chelidonichthys Lucerna L. 1758) In The Bay Of İskenderun In The Eastern Mediterranean, Ali̇ İşmen, Pinar İşmen, Nuri̇ Başusta Jan 2004

Age, Growth And Reproduction Of Tub Gurnard (Chelidonichthys Lucerna L. 1758) In The Bay Of İskenderun In The Eastern Mediterranean, Ali̇ İşmen, Pinar İşmen, Nuri̇ Başusta

Turkish Journal of Veterinary & Animal Sciences

The age composition, growth parameters, spawning season, sex ratio, length at first sexual maturity and fecundity of tub gurnard (Chelidonichthys lucerna) caught from the Bay of İskenderun in the eastern Mediterranean Sea were investigated. Females and males made up 58.2% and 41.8%, respectively, of the particular population of the species. The total length of females ranged from 8.0 cm to 30.3 cm, and of males from 8.3 cm to 21.2 cm. The length (L) - weight (W) relationships for males and females were estimated as W = 0.0089*L^{3.01} and W = 0.0095*L^{2.99}, respectively. The age data derived from otolith readings …


Some Biological Properties Of Mosquitofish Populations (Gambusia Affinis) Living In Inland Waters Of The Western Mediterranean Region Of Turkey, Şükrü Öztürk, Ramazan İki̇z Jan 2004

Some Biological Properties Of Mosquitofish Populations (Gambusia Affinis) Living In Inland Waters Of The Western Mediterranean Region Of Turkey, Şükrü Öztürk, Ramazan İki̇z

Turkish Journal of Veterinary & Animal Sciences

Gambusia affinis, Baird & Girard, 1853, originally comes from North America and has been distributed all over the world for the biological control of mosquitoes. This study aimed to determine some biological properties, such as structure, age, growth and reproduction of the populations of G. affinis in Turkey. For this purpose, between November 1998 and October 1999, 2026 mosquitofish were caught in the wetlands of Fethiye-Akgöl, Dalaman and Ortaca in Muğla province in the western Mediterranean region of Turkey and the data found were compared. In the Fethiye-Akgöl population the percentage of the 0+ age group was 97.59%, and of …


The Reproduction Biology Of Chub (Leuciscus Cephalus L. 1758) In Topçam Dam Lake (Aydın, Turkey), Hüseyi̇n Şaşi Jan 2004

The Reproduction Biology Of Chub (Leuciscus Cephalus L. 1758) In Topçam Dam Lake (Aydın, Turkey), Hüseyi̇n Şaşi

Turkish Journal of Veterinary & Animal Sciences

In this study, the reproduction biology of 332 chub (Leuciscus cephalus L. 1758) was studied from June, 1999, to June, 2000, on a monthly basis in Topçam Dam Lake. Egg numbers were estimated in 65 females caught just prior to spawning. The sex and age compositions of chub were determined. The specimens were composed of 27.11% males and 72.89% females. Male and female chub become sexually mature in the second year of their life spans. Spawning is in March and April. The fecundity of chub varies from 2100-66,400 per female. The average egg diameter was between 0.391 and 0.744 mm …


Investigation Of Some Population Parameters Of Common Sole, Solea Solea (L., 1758) From İskenderun Bay, Mustafa Türkmen Jan 2003

Investigation Of Some Population Parameters Of Common Sole, Solea Solea (L., 1758) From İskenderun Bay, Mustafa Türkmen

Turkish Journal of Veterinary & Animal Sciences

Data on age, growth, reproduction, mortality and exploitation were examined for common sole collected in İskenderun Bay from March 2000 to February 2001. The examined individuals were aged between 1 and 8 years. Total length ranged from 8.8 to 28.2 cm. The length-weight relationships for males (a = 0.0117, b = 2.998) and females (a = 0.0091, b = 3.077) showed no significant difference from isometric growth. Von Bertalanffy growth parameters were L_{\infty} = 26.03 cm, k = 0.221 year^{-1}, t_o = -1.31 for males and L_{\infty} = 29.95 cm, k = 0.181 year^{-1}, t_o = -1.55 for females. The …


Gonad Histology And Spawning Pattern Of The White Grouper (Epinephelus Aeneus) From İskenderun Bay (Turkey), Mahmut Ali̇ Gökçe, İbrahi̇m Cengi̇zler, A. Argun Özak Jan 2003

Gonad Histology And Spawning Pattern Of The White Grouper (Epinephelus Aeneus) From İskenderun Bay (Turkey), Mahmut Ali̇ Gökçe, İbrahi̇m Cengi̇zler, A. Argun Özak

Turkish Journal of Veterinary & Animal Sciences

The gonad histology and spawning pattern of the white grouper (Epinephelus aeneus) were determined from fish sampled from commercial catches. Histological, microscopic and macroscopic techniques were used to examine the ovaries of E. aeneus. A six stage maturity scale based on morphology was proposed to classify ovarian development. The results showed that the white grouper has an asynchronous mode of ovarian development, and the histological study of oocyte development in the white grouper indicated that two types of inclusion, first lipid and then protein, are formed during vitellogenesis. Towards maturation, protein granules and lipid droplets increased in size and number …


Reproduction Of The Silverbelly (Leiognathus Klunzingeri Steindachner, 1898) In Yumurtalık Bight (Adana), Turkey, Meltem Özütok, Dursun Avşar Jan 2003

Reproduction Of The Silverbelly (Leiognathus Klunzingeri Steindachner, 1898) In Yumurtalık Bight (Adana), Turkey, Meltem Özütok, Dursun Avşar

Turkish Journal of Veterinary & Animal Sciences

This present study was performed to identify reproductive peculiarities of the silverbelly (Leiognathus klunzingeri) in Yumurtalık Bight. For this purpose, 430 individuals were obtained by monthly sampling between October 1997 and September 1998 and then they were examined. By using the monthly changes in the mean values of the Gonadosomatic Index (GSI) and Fulton's Condition Factor (K), we found that reproduction period occurred between July and September, length at first maturity was 5.8 cm and 5.5 cm for males and females, respectively, egg diameter was between 0.8 and 1.0 mm and mean annual fecundity was 2789 ± 2109.


Studies On The Age, Growth And Reproduction Characteristics Of The Chub, Leuciscus Cephalus Orientalis, (Nordmann, 1840) In Karasu River, Turkey, Orhan Erdoğan, Mustafa Türkmen, Ayhan Yildirim Jan 2002

Studies On The Age, Growth And Reproduction Characteristics Of The Chub, Leuciscus Cephalus Orientalis, (Nordmann, 1840) In Karasu River, Turkey, Orhan Erdoğan, Mustafa Türkmen, Ayhan Yildirim

Turkish Journal of Veterinary & Animal Sciences

This study is based on the examination of 759 chubs from Karasu River (40° 45´ 33´´ E, 39° 56´ 16´´ N) between November 1995 and October 1997. This population comprised seven age groups of males and nine of females. The second age group was dominant in the population. Individuals were composed of 50.46% males and 49.54% females. The male and female ratio was 1:1.019 (M:F). The Von Bertalanffy growth parameters and length-weight relationships were; L_t = 35.8765 (1-e^{-0.1241(t+1.16660)}), W_t = 583.2981 (1-e^{-0.1241(t+1.16660)})^{2.952}, W = 0.0150 FL^{2.952} in males and L_t = 41.4154 (1-e^{-0.1160(t+1.3207)}), W_t = 936.3338 (1-e^{-0.1160(t+1.3207)})^{2.980}, W = 0.0142 …