Living and dead foraminiferal assemblage from the supratidal sand Japsand, North Frisian Wadden Sea: distributional patterns and controlling factors

Supratidal sands are vitally important for coastal defence in the German Wadden Sea. They are less affected by human activities than other areas as they are located far off the mainland shore, touristical and commercial activities are generally prohibited. Therefore, supratidal sands are of high ecological interest. Nevertheless, the faunal inventory and distribution pattern of microorganisms on these sands were studied very little. The composition of living and dead foraminiferal assemblages was therefore investigated along a transect from the supratidal sand Japsand up to Hallig Hooge. Both assemblages were dominated by calcareous foraminifera of which Ammonia batava was the most abundant species. Elphidium selseyense and Elphidium williamsoni were also common in the living assemblage, but Elphidium williamsoni was comparably rare in the dead assemblage. The high proportions of Ammonia batava and Elphidium selseyense in the living assemblage arose from the reproduction season that differed between species. While Ammonia batava and Elphidium selseyense just finished their reproductive cycles, Elphidium williamsoni was just about to start. This was also confirmed by the size distribution patterns of the different species. The dead assemblage revealed 20 species that were not found in the living assemblage of which some were reworked from older sediments (e.g., Bucella frigida) and some were transported via tidal currents from other areas in the North Sea (e.g., Jadammina macrescens). The living foraminiferal faunas depicted close linkages between the open North Sea and the mainland. Key species revealing exchange between distant populations were Haynesina germanica, Ammonia batava and different Elphidium species. All these species share an opportunistic behaviour and are able to inhabit a variety of different environments; hence, they well may cope with changing environmental conditions. The benthic foraminiferal association from Japsand revealed that transport mechanisms via tides and currents play a major ecological role and strongly influence the faunal composition at this site.

Portuguese Artisanal Fishers’ Knowledge About Elasmobranchs—A Case Study

The high economic value of fisheries was historically associated to commercial teleost fishes. Since the 1970s, despite some elasmobranchs becoming an important target or a bycatch, relatively little research has been carried out on this group because of their low economic value. Due to their specific life history characteristics, sharks and rays are particularly vulnerable to overexploitation, taking several decades to recover after reaching an overexploitation status. In Portugal elasmobranch fishery results mainly from targeted longlining and bycatch from different fishing gears. During the last decade, the Total Allowable Catches (TACs) of rays have been decreasing, the European Union (EU) banned the capture of some ray species, the Portuguese government implemented both a closed season and a minimum landing size for some rays, and the EU prohibited target fishing for sharks. All these measures may have been highly responsible for the national and local landings reduction. Official landings from the last decade were analyzed, the landed species conservation status was consulted, and structured interviews using a questionnaire were conducted in the most important fishing port in the Portuguese mainland, the port of Sesimbra. Results led us to conclude that fishers’ answers and landings data did not match. It also revealed a lack of awareness by fishers about the state of shark and ray populations, and about some aspects of their biology and ecology, like reproduction season and method. The present study highlights the need to fill in this existing gap in knowledge through the transfer of scientific knowledge and sharing of management responsibilities. Also, we aimed to demonstrate the necessity for awareness and education activities within fishing communities, an essential step to elasmobranch conservation.

Sub-Clinical Mastitis and Reproduction: Season, Parity and Stage of Lactation Effects on Conception Rate and Milk Somatic Cell Count

The aim of the present study was to investigate the effect of subclinical mastitis (somatic cell count (SCC)>250000 cells/ml) on the fertility of Holstein dairy cows in different parities, lactation stages and seasons. Data of 2437 SCC in a dairy farm including number of insemination, pregnancy detection, date of calving and insemination, SCC after insemination (maximum of 30 days), and parity were evaluated. The rate of subclinical mastitis in the first, second, third and fourth and more lactation number was 18.8%, 25.7%, 26.5% and 35.4%, respectively and in spring, summer, autumn and winter was 24.5%, 19.7%, 18.5% and 33.6%, respectively. Conception rate of cows with subclinical mastitis (24.6%) was lower than cows without subclinical mastitis (30.9%; P=0.003). In addition, the conception rate in the second and third lactation in cows with subclinical mastitis was significantly lower than in cows without subclinical mastitis. The conception rate of cows with subclinical mastitis in summer in the second lactation and in winter in the second and third lactation was significantly lower than in cows without subclinical mastitis. Therefore, subclinical mastitis in mid lactation stage and also in the second and third parities especially in summer and winter can disturb fertility more than the other conditions. Also, considering these facts during these periods of times in managing of subclinical mastitis can improve fertility outcome of the herd.

Reproductive Cycle and Fecundity Tristramella simonies (Gunther, 1864) (Teleostei: Cichlidae) in the Northern Great River (Lattakia, Syria)

This research was conducted to study the reproductive cycle and fecundity of the fish Tristramella simonis in the Northern Great River (Nahr Alkabeer Alshmali) north of Lattakia city. 263 individuals were collected from the northern great river, during the period between July 2017 and June 2018. Samples were collected every 15 days using gill nets, which its pores diameter ranged from 16 to 20 mm and using cages (1 × 1 × 1 m). The total length of the collected fish ranged from 9.5 to 16.5 cm, and their weights ranged from 19.5 to 112.27 g. Samples contained (128 females) and (88 males) and (47) undetected. Results of Gonado Somatic Index (GSI) showed that the reproduction period was between April and August with three obvious peaks of maturity. Where the highest value of GSI was (10.06±8.46) % for females and (0.13 ± 0.05) % for males. Results of Hepato Somatic Index (HSI) was concurrence highly with the ecological and physiological changes, which result from changes in sexual activity during the reproductive cycle. Where the highest value of HSI attained 3.79 ± 1.86 % for females and attained 3.95 ± 1.38 % for males. In the first sexual maturity, the length attained 13.31 cm for females and (14.87 cm) for males. The sexual rate was (1: 0.7), which means 40.7 % males and 59.3 % females in the population. The absolute fecundity ranged from 940 to 1229 egg. While the relative fecundity ranged between 158- 215 egg/ g of ovary weight. Egg diameter during reproduction season ranged between 2.4- 4 mm, with several sizes, which mean a relatively long reproduction term.

Hematological Profile in Donkey Depending on Lactation

The factors that influence the hematological profile of the donkeys are: nutrition, reproduction, season, lactation, parturition, maintenance and animal health. Knowing the hematological parameters represents a breakthrough in the development of work programs and nutritional programs in the donkey farms and greatly helps the possibility of the conservation of the donkeys, a species that until now has been neglected in our country. For haematological parameters, significant changes can be observed under the influence of lactation as follows: WBC (G/L) may have a lower mean average in lactation I, (9.66 ± 0.56) and further in lactation, reaching a higher value average in lactation IV (13.57 ± 0.80). Hb (g/L) behaves similar to WBC, reaching the highest average values in IV lactation, (131.30 ± 3.56). LYM (%) in lactation I, (38.72 ± 0.69) and in lactation 2, 3 and 4 similar average values. MON (%) manifests thus, under the influence of lactation, having an interval between (1.14 ± 0.16), lactation I and (1.42 ± 0.17) in lactation IV.

Reproductive biology of the mutton hamlet on the coast of Pernambuco, northeastern Brazil

This paper focuses on the reproductive biology of the Mutton Hamlet, Alphestesafer, a fish belonging to the family Epinephelidae, and aims to provide information on the main reproductive parameters of the species on the north coast of the state of Pernambuco, northeastern Brazil. From a total of 783 individuals, collected between March 2007 and June 2010, and from February to November 2014, the gonads of 322 fishes (235 females and 87 males) were analyzed, for the identification of sex and maturational stages. Females were more abundant and larger than males, with a sex ratio of 2.4 females: 1 male, during the reproduction season. The size at first maturity (L50) was estimated at 16.8 cm total length for females, and 16.2 cm for males. The gonadosomatic index (GSI) indicated that a reproductive cycle occurs all year round, while reproduction takes place from June to November. The fecundity of Alphestesafer ranged from 105,317 to 270,192 oocytes, averaging 173,458 oocytes. The females are more abundant than males due to the process of protogyny and also because individuals are regularly captured at growth stages above the L50, being a positive aspect for the sustainability of the fishery. According to the GSI, the species presents a split-type spawning with two peaks occurring throughout the year.

Seasonal Variation of Captive Meagre Acoustic Signalling: A Manual and Automatic Recognition Approach.

Many species rely on acoustic communication to fulfil several functions such as advertisement and mediation of social interactions (e.g., agonistic, mating). Therefore, fish calls can be an important source of information, e.g., to recognize reproductive periods or to assess fish welfare, and should be considered a potential non-intrusive tool in aquaculture management. Assessing fish acoustic activity, however, often requires long sound recordings. To analyse these long recordings automatic methods are invaluable tools to detect and extract the relevant biological information. Here we present a study to characterize meagre (Argyrosomus regius) acoustic activity during social contexts in captivity using an automatic pattern-recognition methodology based on the Hidden Markov Model. Calls produced by meagre during the breading season showed a richer repertoire than previously reported. Besides the dense choruses composed by grunts already known for this species, meagre emitted successive series of isolated pulses, audible as ‘knocks’. Grunts with a variable number of pulses were also registered. The overall acoustic activity was concurrent with the number of spawning events. A diel call rhythms exhibit peak of calling activity from 15:00 to midnight. In addition, grunt acoustic parameters varied significantly along the reproduction season. These results open the possibility to use the meagre vocal activity to predict breeding and approaching spawning periods in aquaculture management.

Dynamic Modes of Limited Structured Population under Age Specific Harvest

The paper investigates influence of age specific harvest on the dynamics of populations with density dependent regulation of birth rate. We consider the population which by the end of each reproduction season, consists of two age groups: juveniles (immature individuals) and adults (participants of the reproduction process). A harvest rate growth of any age class is shown to give, as a rule, the dynamics stabilization. However, the system with harvesting demonstrates multimodality phenomenon as well as the population model without exploitation. The phenomenon means different dynamic modes are observed with the same values of the population parameters. As a result, some difficulties occur in predicting population dynamics, because harvest can lead to significant changes of population size due to shifting current population size from one attraction basin to another. To neutralize the oscillations emerged is necessary to change the current population size so that it falls into the attraction basin of the fixed point. The stability loss way of model with juvenile harvesting does not depend on the harvest rate value and is completely determined by the intensity of competitive relationships between the age classes. In the case of adult exploitation, a higher harvest rate can result in growing stationary population size. The changing the time of adult harvesting can lead to both the dynamics population stabilization and the occurrence of fluctuations. Exploitation before the reproduction season allows to have more yield than after reproduction season because mature age group size is higher. Conditions when the age specific harvest gives the maximum sustainable yield are considered.