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Many species in the family Serranidae are hermaphrodites and of commercial importance. Paranthias colonus belongs to this family, and its reproductive traits are unknown. The present research was carried out with specimens taken from the commercial fishery on the southern coast of Jalisco, Mexico. A total of 1,541 specimens were processed, with an average length of 30.30 ± 0.10 cm and a length interval of 19.80 to 38.00 cm. Specimen gonads were analyzed macro- and microscopically. The sex ratio was 1.00:0.97 (F:M). According to the maximum monthly values of the gonadosomatic index, gonad maturity stages, and oocyte diameters, P. colonus has 2 broad reproductive periods, from March to June and from November to December. A significant correlation was found between the monthly mean values of the gonadosomatic index and the relative condition factor. Gonads in the mature stage had oocytes in 6 different development phases, with diameters that ranged from 14.30 to 417.40 μm, which means that oocyte development is asynchronous. In the testicle, the development of the germ line is of the unrestricted lobular type. This organ did not present the typical arrangement found in teleost fish, since lobes seem to be delimited by lamellae. The information developed in this study indicates that P. colonus is a gonochoric species. Average length at sexual maturity was 26.80 cm for females and 26.90 cm for males. Average catch lengths indicated that 79.70% of females and 83.30% of males had already reproduced at least once before being caught. [ABSTRACT FROM AUTHOR]

Copyright of Acta Zoologica Lilloana is the property of Fundacion Miguel Lillo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reproductive tactics and strategies contribute to the persistence and maintenance of long-term populations in fish species. Members of the subfamily Goodeinae are a group of small-bodied freshwater fish with specialized reproduction (viviparitymatrotrophy). They are found in the highlands of central Mexico, most of them endemic. The aim of this study was to conduct a comprehensive investigation to evaluate the annual reproductive cycle of seven species of goodeines (splitfins). We carried out our study in the subtropical Lake Zacapu, Mexico, with bimonthly sampling from May 2019 to March 2020. We obtain the fertility, size at first maturity (L50), sex ratio, and gonadosomatic index. Our result shows that populations of goodeines have high fertility compared to other populations of the same species in other aquatic systems and also to other species of goodein. We found that males mature at smaller sizes than females, the observed proportion of females was greater than males in all the goodeines. Lake Zacapu goodeines have two reproductive peaks, one in spring (April to June) and another in fall (September to November). These tactics (fertility rates, sex ratio, reproductive period) and strategies (viviparity-matrotrophy) favor reproductive success in this environmentally stable subtropical lake in the highlands of Mexico. [ABSTRACT FROM AUTHOR]

Introduction: Estimates of contemporary connectivity of the broadcast spawning coral Pocillopora verrucosa between multi-use marine protected areas (MUMPAs) are required to assess MUMPA effectiveness and their ability to enhance resilience against disturbances. Objective: To determine the genetic structure and connectivity patterns between P. verrucosa demes inside the Gulf of California and evaluate the role and effectiveness of established MUMPAS in their protection and resilience. Methods: We assessed P. verrucosa connectivity along its peninsular range (~350 km), including five locations and three MUMPAs in the Gulf of California using six microsatellite genetic markers. Results: Population structure was significant (FST = 0.108***) when demes included clonal replicates; however, when these clones were removed from the analysis, the sexual individuals comprised a metapopulation panmixia (FST = 0.0007 NS). To further understand connectivity patterns, an assignment test was carried out which identified ten recent between-deme migrants with a mean dispersal distance of 116.6 km (± 80.5 SE). No longdistance dispersal was detected. These results highlight the ecological importance of the Bahía de La Paz region, including Archipiélago de Espíritu Santo MUMPA. This region, located at the center of the species peninsular range, exports larva to downstream sink demes such as the Loreto (northwardly) and Cabo Pulmo (southwardly) MUMPAs. Of importance, inter-MUMPA spacing was larger than the mean larval dispersal by ~56 km, suggesting thar the designation of intermediate 'no-take' zones would enhance short-distance connectivity. Conclusion: This study contributes as a baseline for policymakers and authorities to provide robust strategies for coral ecosystem protection and suggest that protection efforts must be increased towards peninsular intermediate reefs to promote metapopulation resilience from natural and anthropogenic factors. [ABSTRACT FROM AUTHOR]

Since 2000, no reviews or analyses have been carried out on scientific studies regarding bat reproductive biology. Such reviews might contribute towards identifying information gaps and global research focus and trends.The objective of this work was to review and analyse scientific studies on different aspects of bat reproduction published in the last two decades (2000–2019), in order to provide perspective for future research.Using 19 key words, we searched for literature on the reproduction of bats published as book chapters and articles in scientific research journals globally. We analysed 36 chapters in 14 books and 276 scientific articles, from 41 countries, identifying publishing trends throughout the years, preferred journals, countries in which studies have been carried out, and most‐studied species and topics.The number of studies increased over the last decade, resulting from the consolidation of research lines in countries such as Brazil, India, Mexico, and USA. The studies covered 125 species, of which Scotophilus heathi and Cynopterus sphinx were the most recurrent, each appearing in 23 studies (7.4%, n = 312). The most common subject was anatomy (61 studies, 20%, n = 312), and the rarest was assisted reproduction techniques (11 studies, 3.5%, n = 312).In the last decade, there has been a trend to increase the study of male anatomy. The application of new techniques for the study of reproduction contributed to more complex studies that favour the understanding of the reproductive process. There is an evident lack of reproductive studies for most species, and there is an information gap regarding research in prenatal development and assisted reproduction techniques. These two topics are greatly significant for future research, because of their direct usefulness for species conservation. [ABSTRACT FROM AUTHOR]

Quantification of steroid hormones in molluscs is performed with different techniques, using the hemolymph or gonads. Lobatus gigas is a Caribbean gastropod of commercial interest indexed in CITES as a protected species. Hormonal studies of this species are as yet unavailable. The objective of this study is to determine the presence of the steroid hormones 17ß - estradiol and progesterone in L. gigas using a non-invasive method, and to compare two techniques for their quantification. Every two months over the course of one year, the feces of ten organisms were collected in Xel-Ha park Quintana Roo, México. The samples were analyzed with High resolution liquid chromatography and Enzyme-linked immunosorbent assays. The values of both hormones were highest during the months of March to September then decreased during November and January. Comparison of the concentrations obtained with HPLC and EIA, presented similar results for 17ß-estradiol (Passing - Bablock r = 0.673; mean differences -0.17 ng / ml). In contrast, the progesterone results with both techniques showed no adjustment (Passing - Bablock r = 0.389; mean differences -1.43 ng / ml). Our results suggest that the enzyme-linked immunosorbent assay is suitable for the study of hormones in L. gigas. The knowledge generated will allow the monitoring and selection of breeding organisms that are conditioned in laboratories and thus will not affect the collection of wild egg masses. [ABSTRACT FROM AUTHOR]

Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Spondylus limbatus is a species under special protection in Mexico, of which there is little or no information in the literature of biological, histological or ultrastructural studies of the ovary. The objective of this research was to characterize the ultrastructural morphology of mature and degenerating female gametes. The female gonad of S. limbatus in mature state presented post-vitellogenic oocytes 60-70 mm in diameter, which have characteristics of metabolically active and highly synthesizing cells. The cytoplasmic membrane has specializations designed to increase the absorption surface of the cell, the microvilli; the cytoplasm presents numerous membranous systems related to synthesis of reserve and secretion material as well as the highly lobed nuclear organization pattern; a large surface that ensures core-cytoplasm exchange, is structurally incorporated into the vitellogenesis process. Finally, ultrastructural changes resulting from the lysis of the oocytes are described: collapse of nuclear and cytoplasmic membranes, and the presence of macrophage hemocytic cells. [ABSTRACT FROM AUTHOR]

Copyright of Agro Productividad is the property of Colegio de Postgraduados and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Latin American & Caribbean Anthropology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The winged pearl oyster, Pteria sterna, sustains a growing pearl industry in northwestern Mexico, where a subtropical climate prevails. In tropical areas of Mexico, pearl cultivation may be profitable, but insufficient information on the biology and ecology of the species limits the definition of protocols for creating pearl farms. We measured absolute growth, growth rate, reproductive stages, changes in oocyte size, and size at first maturity of juvenile P. sterna cultivated in Bahía de Acapulco over one annual cycle (2009-2010), and compared their response in this tropical area with reports from subtropical areas of Mexico. We also compared the von Bertalanffy growth model with one proposed in this study for aquaculture purposes. The growth rate was higher during the first six months (5.3 mm month-1) and then decreased to 3 mm month-1 until juveniles reached a size of 60 mm in one year. Growth rates were higher in February and lower in July through September. Both models described well the growth of P. sterna, but the adjustment and the estimation of parameters was better with the proposed model. Gametogenesis started in December 2009 at 50.9 mm (males) and 59.5 mm (females); gonad development occurred continuously throughout the year with a peak in February-March (~25-26 ℃ 2.8 μg L-1 chlorophyll a concentration), when the gonad index was highest and oocytes were larger. When compared to other studies conducted in subtropical areas, the species uses different strategies to channel available energy into growth and reproduction in tropical regions; P. sterna grows quickly in Bahía de Acapulco and may obtain the size necessary for grafting (70-80 mm shell height) in 15-17 months. [ABSTRACT FROM AUTHOR]

Sexual dimorphism and reproductive cycle were studied in a population of Sceloporus horridus horridus from a tropical dry forest in central Mexico. Males with 90.66 mm (71.5-111.0 mm ± 12.79 mm) snouth vent-length were larger than 86.32 mm (71.0-101.0 ± 7.94) females. Reproductive activity is seasonal in both sexes and occurs in the period spring-summer as it has been observed in several oviparous species of tropical dry forest. The vitellogenesis occurs between March and April and the spermatogenesis from February to March. The ovulation occurs on late April and the eggs are in the oviducts between May-July. Mean eggs mass was 0.46 g (0.3-0.6) and meanclutch size was 15.3 eggs (10-20). Clutch size was related significantly to mass (r = 0.669) and physical condition of females (r = 0.676). The relative clutch mass value was 0.31 conforming to the strategies predicted for sit and wait species of lizards. The on set of reproductive activity in males was related with temperature (r = 0.508) and in females with precipitation (r = 0.775). Liver and fat body mass in males and females, showed an inverse relationship with the peaks of breeding activity. [ABSTRACT FROM AUTHOR]

ABSTRACT Birthing experiences for low-income and marginalized women have frequently been framed within explanatory models of authoritative knowledge and power dynamics. Many of these explanatory models have pointed out the structural violence inherent in the biomedical model of birth. The research on which this article is based suggests that clinicians' stressful work environment and class-based stereotypes of low-income women resulted in the routinizing of inhumane medical practices. Hospital overcrowding due to health reforms led to clinicians being primarily concerned with moving patients swiftly through the system. Clinicians increasingly relied on the cervical examination as a marker for labor's progress and a shorthand method to track cervical dilation. Using ethnographic data collected in the obstetrics ward of a public hospital in Mexico, in this article I explore the emergence of a bureaucratic routinizing of obstetricians' everyday practice. I provide a new understanding of the encoding and entrenching of everyday medical practices and their effect on the reproductive rights of women. [ABSTRACT FROM AUTHOR]

Monthly samples of Pacific sierra Scomberomorus sierra were taken during nine years (1998-2000 and 2002-2007) with gillnets in Navidad Bay, Jalisco (Mexico). The sex ratio for the whole sampling period was not significantly different from 1 (F:M, 1:0.9). Monthly trends of the gonadosomatic index, the percentage of individuals with ripe gonads, and mean oocyte diameter indicate that this species reproduces in the period from April to June (spring). This reproduction period is also supported by the microscopic characteristics of gonads (highest percentage of oocytes in advanced vitellogenesis phase and high concentration of spermatozoa in lobular lumen and testis main duct). Total length (TL) ranged from 26.0 to 102.8 cm, with a mean of 53.3 cm. Mean maturation lengths calculated for females and males were 59.3 and 56.4 cm TL, respectively. Most individuals caught had a length which was smaller than the mean maturation length indicating that the fishery is based mostly on juvenile fish. [ABSTRACT FROM AUTHOR]

The abundance and reproduction of the brown pelican (Pelecanus occidentalis) was studied in two bays of the Mexican Central Pacific, Bahía de Navidad and Bahía Chamela, located in the coast of Jalisco, Mexico. The number of brown pelicans in both bays was registered from December 2007 to November 2009, as well as the number of nests, eggs and nestlings in the Cocinas Island. The superficial temperature of the water, the nutrients (NO 2-, NO 3-, NH 4+ y PO 4-) and the primary productivity (clorofile a) were measured on a monthly basis. The greater number of pelicans was registered from January to March, in both bays. There were a bigger number of birds in the Chamela bay, mainly in early 2009. The reproductive period of the brown pelican extended from December to July on both years. The largest number of nests was observed in March and April, with an estimate of 480 (90.7 nests/hectares) in the whole nesting season of 2008 and 1,200 (226.8 nests/hectares) in 2009. In 2008 there were an estimate 1,310 eggs and 800 nestlings, while in 2009 there were an estimate 3,348 eggs and 2,200 nestlings. Both, the highest number of birds, as well as the highest number of nests, eggs and nestlings registered in 2009 were present when the temperature of the water registered its lowest values and the primary productivity (clorofile a) and nutrients, mainly NO 3- and PO 4-, registered their highest levels. These variables have a direct effect in the concentration of a larger number of fish. [ABSTRACT FROM AUTHOR]

We report on the proportion of maturity stages as a function of size of the Pacific sharpnose shark Rhizoprionodon longurio. Based on the development of internal and external organs, males and females were classified as immature or mature. A logistic model was fitted to develop a maturity curve to estimate the length at which 50% of the individuals are mature (L50%). This species has an annual reproductive cycle and its birthing season is from April to July, with June as the main month. For males, L50% = 100.61 cm total length (TL) and ɸ= 2.57, and for females, L50% = 92.9 cm TL and ɸ= 1.08. For pregnant females, L50% = 106.4 cm TL and ɸ= 6.11. The maturity curves obtained in the present study can be used in demographic studies to produce more accurate forecasts of the population reproductive rate and thus develop fishery management measures for this species. [ABSTRACT FROM AUTHOR]

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Diodon holocanthus is an important economic and ecological species of the demersal fish community, caught as bycatch from local shrimp fishery. The reproductive biology of this longspine porcupinefish has not yet been described, and reproductive season, the sex ratio, length distribution, length at first gonad maturity, and the gonad macro and microscopic features are described. A total of 400 organisms, ranging from 5.0 to 40.3cm (average 18.4cm) total length, were caught from the continental shelf of the Central Mexican Pacific, from December 1995 and December 1998. Sex ratio was 1:0.86 females to males (n=253). The length at which 50% of the individuals showed maturing gonads was 19.7cm for females and 20.1cm for males. Length of the smallest organism with ripe gonads was 12.2cm for females and 13cm for males. Four gonadal maturation stages were found in both sexes, and five oocyte development phases were identified. The oocyte development pattern is of asynchronous type, which means the species can reproduce several times a year. Testicle development is lobular type, as in most teleost fishes. Monthly mean values of the gonad-somatic index suggest the reproduction activity peaks in June, and September-December. Rev. Biol. Trop. 59 (1): 217- 232. Epub 2011 March 01. [ABSTRACT FROM AUTHOR]

La capacidad reproductiva de las comunidades coralinas en el Pacífico mexicano está poco documentada. Una de las comunidades de coral más abundantes de esta región se encuentra en Bahía de Banderas; sin embargo, los patrones reproductivos de las especies de corales no han sido analizados. Con el objetivo de documentar el ciclo reproductivo anual de las tres especies de corales más abundantes en la bahía, se recolectaron muestras mensuales de Pocillopora damicornis, Porites panamensis y Pavona gigantea frente a Isla Redonda, de diciembre de 2001 a noviembre de 2002. Los fragmentos de las colonias se procesaron mediante técnicas histológicas y se analizaron con ayuda del microscopio. Las tres especies mostraron presencia de gametos, la cual se asoció con el incremento de la temperatura superficial del mar. La primer especie en presentar gametos fue P. damicornis, clasificada como hermafrodita. Porites panamensis presentó gametos a partir de mayo de 2002, y embriones y plánulas en septiembre del mismo año; esta especie se consideró como gonocórica, con fecundación interna y con comportamiento reproductivo diferente a lo reportado en otras localidades del Pacífico oriental tropical. Pavona gigantea fue la última especie en presentar gametos y por un periodo corto; se clasificó como gonocórica y no se observaron gametos maduros. Las tres especies mostraron un potencial reproductivo que se circunscribió al periodo de verano, lo que confirma la capacidad reproductiva documentada para estas especies en regiones aledañas del Pacífico mexicano. La intensidad y duración de los periodos reproductivos en Bahía de Banderas podrían estar en función de la presencia de fenómenos periódicos, como El Niño, y oscilaciones climáticas a nivel de microescala que afecten los patrones de temperatura e intensidad de luz en la bahía. [ABSTRACT FROM AUTHOR]

The article uses in-depth interviews with owners of small businesses in Mexico City, Mexico, to provide empirical and theoretical analysis of the reciprocal effects of families on their small businesses and the businesses on the family dynamic. The author seeks to determine the relationships that arise between family members as a result of their work activities together, as well as to verify whether those relationships can ensure continued production for the business while maintaining adequate consumption and supply for the family unit. The social and economic effects of sharing both domestic and professional space with family members are also discussed.

Copyright of Revista Mexicana de Biodiversidad is the property of Universidad Nacional Autonoma de Mexico, Instituto de Biologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

El objetivo fue determinar el porcentaje óptimo de genes Bos taurus (BT) para edad al primer parto (EPP), días al primer servicio (DPS), días abiertos (DA) e intervalo entre partos (IEP) de vacas cruzadas. La información analizada se originó de 1,704 lactancias completas de 677 vacas desde 100 % Bos indicus (BI) hasta 100 % BT de un rancho lechero típico mexicano de Tabasco. El análisis fue con un modelo mixto que incluyó los efectos fijos de número de parto de la vaca, el año de parto y la estación de parto de la misma, los efectos aleatorios de semental, vaca anidada en semental, y el efecto racial lineal de porcentaje de genes BT como covariable. Las vacas de cuarto parto tuvieron DPS más cortos que las de segundo y tercero; éstas a su vez fueron diferentes a las de primero. Paralelamente, los animales de segundo ó más partos presentaron DA e IEP más cortos (P<0.05) que las de primero. La EPP fue mínima (31 meses) con 49 % de genes BT; después de dicha proporción el mismo parámetro incrementó hasta 36 meses. Las vacas con 100 % de genes BI presentaron DPS (106 d), DA (166 d) e IEP (14.6 meses) inferiores que las demás cruzadas con BT. En conclusión, las vacas con 50 % de genes BT alcanzan la EPP más temprano y tienen DPS, DA e IEP más prolongados; por lo tanto, dichas vacas representan los genotipos óptimos para la región tropical húmeda. [ABSTRACT FROM AUTHOR]

Amphibians are disappearing worldwide. Several species have been lost, and thousands are in danger of extinction. Of the threatened species, some can not be protected in their own natural habitat, therefore it is imperative to accomplish ex-situ conservation actions that assure its preservation. Ambystoma granulosum and Ambystoma lermaense, are species in high priority to be protected by mean of this conservation strategy, since they are endemic species of Mexico and with a concern conservation status. Both species have been little studied, therefore in this study we investigated reproductive aspects that are vital for its conservation, as reproduction in laboratory, and hormonal induction with human chorionic gonadotrophin (hCG). Our results showed not significant difference in the sex morphology for both species, except for the swollen vent in the cloacal region of males. The reproductive cycle is annual and synchronic in males and females, with a maximum of activity from May to September. We obtained clutches only from couples of A. granulosum without hormonal induction in variable numbers with an average of 664 ± 325(SD) eggs and a fecundity from 40 to 90%. We obtained nine clutches from couples of Ambystoma granulosum with hCG induction ranging between 17 and 1182 eggs. In couples of Ambystoma lermaense induced, were obtained 16 clutches, ranging between 110 and 1691 eggs. We analyzed possible causes for the variability in fertility of eggs obtained by induction. [ABSTRACT FROM AUTHOR]

The article examines local power and political clientelism in Puebla, Mexico through a study of the Ávila Camacho family, which rose to power following the Mexican revolution in the early and mid 20th century. The article analyzes the biographical aspects and leadership characteristics of family members, as well as reproduction arrangements, which helped the family to consolidate power. It also notes factors which led to the family's political decline. The article maintains that the rise of many political families in Mexico is determined by their ties to social and political networks that provide access to circles of regional and national political power.

Information on geographic distribution, habitat, measurements, and reproductive condition of nine species of bats from Guerrero, Mexico, is provided. Four species are the second records for the State (Choeroniscus godmani, Myotis auriculus apache, Myotis thysanodes aztecus and Nyctinomops femorosaccus), three are the third record (Musonycteris harrisoni, Chiroderma salvini scopaeum and Enchisthenes hartii), and two are the fourth record (Hylonycteris underwoodi minor and Myotis californicus mexicanus). [ABSTRACT FROM AUTHOR]

Field research was conducted during 2005 and 2006 in central Veracruz, Mexico. We worked with 38 families of undocumented migrants and five men who have returned to the localities. The objective was to analyze the factors detonating of migration in four locations, as well as the role played by diverse social networks in the phenomenon, and family dynamics as a result of the absence of male or economic provider. The results showed as triggers of migration seeking better opportunities for jobs and quality of life, based on a modification of the work ethic and expectations that can not get in Mexico, and where various types of networks facilitate the departure of migrants, stay in the United States, and job search. There was continuity and strengthening the structure and dynamics of extended domestic groups, and the prevalence of patrilineal hierarchical roles, where women, maintain the traditional domestic role, without economic independence, under the tutelage economic and moral advancement of the kindred male absent. With regard to the use of remittances, the will of man is executed through their relatives, while retaining the traditional roles of a type of marriage at a distance, not based on the co-residence. [ABSTRACT FROM AUTHOR]

A reproductive analysis of 1 225 specimens of Poeciliopsis gracilis obtained through monthly samples from Coatetelco, a tropical shallow lake in Central Mexico, was made. There was an evident sexual dimorphism, including a difference in body size at the onset of reproduction. Sex ratio deviated significantly from unity. Monthly variations in gonadosomatic (GSI), hepatosomatic (HSI) indexes and ovarian development stages showed that the spawning season was from July to October, coinciding with the rainy season and phytoplankton biomass increase. The largest sizes were 50 mm for females and 43 mm for males. [ABSTRACT FROM AUTHOR]

A total of 707 Gymnothorax equatorialis were collected monthly in the Jalisco and Colima coast, Mexico, from December 1995 to December 1998 and from August to November 1999, in order to determine their reproduction patterns. Females outnumbered and had longer bodies (mean length 54.7 cm) than males (52.1 cm). The minimum, maximum and mean values of total fecundity were respectively 9 660, 99 992 and 32 029 eggs. The total body length at which 50 percent of individuals have ripe gonads (L50) was 43.7 cm for females and 42.7 cm TL for males. Ovaries had two main types of oocytes: small inmature in cromatin nucleolus phase (85.1 μm) and large mature in secundary vitellogenesis phase (701.6 μm). High numbers of spermatozoa were observed in the seminal tubes of ripe testicles, which presented a lobular development. Based in gonad features and temporal changes in the gonad-somatic index, it is concluded that G. equatorialis has two relatively short reproduction periods (at the middle and at the end of the year). [ABSTRACT FROM AUTHOR]

Reproductive data was taken from 322 cows in northern Veracruz to evaluate the calving interval (CI) and age to first calving (AFC). The climate was sub humid and rainy in summer; average temperature and annual rain precipitation were 28°C and 1,400 mm, respectively. The cows were crossbreeds of Brown Swiss, Holstein and Zebu. The feeding was based on stargrass (Cynodon nlemfuensis) and Guinea (Panicum maximum) grazing and cows in production received a supplement of 16% raw protein (3 kg/cow/day) during milking. A lineal model was used to study the effects of breed group (BG), calving year (CY), calving season (CS) and calving number (CN), and the interactions of CY*CS, CY*CN and CS*CN on the CI. And another model was used for AFC which included BG, CY, SC and YC*SC effects. The average for CI was 473.9 ± 145.9 d, the BG, CY, CN, and CY*CN had an effect of (P < 0.01) on CI, though SC, CY*SC and SC*CN did not affect (P > 0.05). The AFC mean was 1225.5 ± 200.5 d, CY, CS and CY*CS affected (P < 0.01) AFC; however, BR doesn't affect (P > 0.05). These results indicated that reproductive problems exist in the herd, as well as the age of first calving is later. [ABSTRACT FROM AUTHOR]

Knowledge of the biological role of the brown shrimp, Farfantepenaeus californiensis, in coastal lagoons is lacking. This species has been classified as oceanic that may or may not enter coastal lagoons in early stages and if it does, it migrates back to the ocean when it attains a size of 35 mm total length (TL). Recently, the brown shrimp has been caught in the Agiabampo coastal lagoon system, in Sonora/Sinaloa (Mexico), and the objective of this study is to describe the reproductive period of this species in that system. Monthly sampling campaigns were carried out from January to December 2002, during five consecutive days. Tows in 24 geopositioned stations were done during high and low tide using 15-m-wide trawl nets. A total of 27,694 organisms were analyzed, with a male:female ratio of 4:3. Based on the proportion of mature females, we determined two reproductive periods: one from June to July (summer) and another from October to November (autumn); however, the average abundance was 20 org ha-1 in summer and 2 org ha-1 in autumn. The average size of mature females was significantly smaller (P<0.05) in summer (129.9 mm TL) than in autumn (134.5 mm TL). Size at first maturity was 145 mm TL in both periods. An important result that contributes to the biological knowledge of F. californiensis is evidence that part of the population matures inside this coastal lagoon and presents one important spawn deposition per year. [ABSTRACT FROM AUTHOR]