Seasonal variation in the diet and the morphometric parameters of the genus Pseudo-phoxinus sp. (Cyprinidae) in Eastern Algeria

The diet and the morphometric parameters of the Pseudophoxinus sp. (Cyprinidae) in the El Mellah ravine (M’sila, Algeria) were studied by determining body measurements and analyzing the contents of digestive tracts of 320 fish from December 2018 to November 2019. The obtained results show marked diversity within the fish species diets, which can be grouped into three main fractions: (i) a plant fraction; (ii) an animal fraction composed mainly of invertebrate prey; and (iii) fraction consisting of fish eggs (digested by males during the breeding season). The plant fraction was present in all the analyzed digestive tracts, mainly being composed of phytoplankton (algae), namely, Spirogyra sp., Melosira sp. and Navicula sp. with the total relative abundances of 38.7%, 34.4% and 4.1%, respectively. On the other hand, the animal fraction was represented by the Chironomus sp., Austrosimulium sp., and Ecdyonurus sp. dipterans with a total relative abundance of 7.3%, 6.7% and 5.9%, respectively. Pseudophoxinus sp. eggs can also be considered as part of this fraction with the total relative abundance of 2.9%. The age of the fish seems to have an influence on their feeding behaviour. The juveniles of Pseudophoxinus sp. in the study area had a purely phytophagous diet, while adults showed a phytophagous behaviour with an omnivorous tendency. The present study shows that not only the age of the fish but also the seasonal changes (climatic conditions and entry into the breeding season) may have a significant influence on the diet and morphometric parameters of Pseudophoxinus sp. in El Mellah ravine.

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Adaptive changes of the hair coat of the horses of zabaykalsky aborigenous breed

Siberian Herald of Agricultural Science ◽

10.26898/0370-8799-2019-4-11 ◽

2019 ◽

Vol 49 (4) ◽

pp. 101-105 ◽

Cited By ~ 1

Author(s):

G. M. Shkyratova ◽

B. Z. Bazaron ◽

T. N. Khamiruev ◽

S. M. Dashinimaev

Keyword(s):

Seasonal Changes ◽

Climatic Conditions ◽

Skin Thickness ◽

Summer Period ◽

Hair Coat ◽

Skin Fold ◽

Winter Grazing ◽

Shoulder Blade ◽

Quantitative Indicators

The seasonal changes in the skin thickness and structure of the horses’ coat, as signs of adaptation to environmental factors, were studied. The experiment was carried out with the livestock kept in a herd using winter-grazing technology without additional feedings in the climatic conditions of the Trans-Baikal Territory. The objects of the research were adult mares of Zabaikalsky breed of horses of the same age, class and fatness. The studies were carried out in the middle of each season (May, July, October, February). The length of the coat was measured with a caliper, the coat itself with the determination of the ratio of hair (ﬂ uffy hair, heterotype hair and coarse hair) and the thickness of the skin fold were measured in accordance with the approved methodological recommendations. The minimum skin thickness in winter was detected in mares on the back and shoulder blade – 4.3 and 4.4 mm, the maximum – on the side and thigh – 4.5 4.6 mm. When compared with the summer period, the increase on the side was 0.8 mm, whereas on the back, shoulder blade and thigh – 0.4 mm (p ≤ 0,001). In spring, thickening of the skin was noted within 0.1-0.3 mm in the same topographic areas, compared to autumn. The quantitative indicators of the coat changed depending on the season of the year. In winter, the coat contained more ﬂ uffy hair (23.10%), and less coarse hair (68.24%), in summer there was a lower content of ﬂ uffy hair (4.33%), but more coarse hair (94.01%.) Sharp seasonal changes were noted with regard to the length of the hair. The longest hair was found in winter and spring – 4.96 and 4.26 cm, whereas the shortest – in summer and autumn – 0.94 and 1.90 cm, respectively.

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Structure of three subtropical bat assemblages (Chiroptera) in the Andean rainforests of Argentina

Mammalia ◽

10.1515/mammalia-2014-0084 ◽

2016 ◽

Vol 80 (1) ◽

Author(s):

Mariano S. Sánchez

Keyword(s):

Species Richness ◽

Relative Abundance ◽

Seasonal Changes ◽

Common Species ◽

Guild Structure ◽

Trophic Guild ◽

Long Tail ◽

Mist Net ◽

Yungas Forests

AbstractI evaluated bat assemblages in terms of species richness, relative abundance, trophic guild structure, and seasonal changes at three sites along of the Southern Yungas forests. A total of 854 individuals were captured, representing 25 species of three families, with an effort of 27,138 m of mist net opened per hour. Subtropical assemblages showed a similar structure to those from tropical landmark, with a dominance of frugivorous Phyllostomid; in addition, a few species were abundant, followed by a long tail of less common species. However, subtropical sites differed due to the dominance of the genus

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Rainfall, Fruiting Phenology, and the Nesting Season of White-Crowned Pigeons in the Upper Florida Keys

The Auk ◽

10.1093/auk/117.2.416 ◽

2000 ◽

Vol 117 (2) ◽

pp. 416-426 ◽

Cited By ~ 5

Author(s):

G. Thomas Bancroft ◽

Reed Bowman ◽

Richard J. Sawicki

Keyword(s):

Breeding Season ◽

Deciduous Forest ◽

Florida Keys ◽

Fruit Production ◽

Climatic Conditions ◽

Fruit Species ◽

Large Peak ◽

Nesting Patterns ◽

Protein Rich ◽

Nesting Season

AbstractWhite-crowned Pigeons (Columba leucocephala) varied their timing of breeding and nesting intensity in response to variation in production of the four most important fruit species in their breeding-season diet in the upper Florida Keys. From 1988 through 1990, we monitored fruit production year-round in five habitats in which pigeons foraged and monitored all pigeon nests along two transects on Middle Butternut Key. Annually, pigeon breeding was positively correlated with summer rains and with the peak in overall fruit production. However, within the breeding season, only the availability of Metopium toxiferum was positively correlated with rainfall and the number of new clutches initiated. Both the timing and magnitude of breeding varied annually. In 1988, when Metopium was more available, more pigeons nested, the nesting season started earlier and lasted longer, and a large peak in nesting occurred when Metopium fruit ripened. During 1989 and 1990, when the relative availability of Metopium was lower, fewer pigeons nested, the nesting season was shorter, and the seasonal peak in nesting associated with Metopium fruit was reduced or absent. Nesting patterns did not appear to vary with changes in the relative availability of other fruits. White-crowned Pigeons appear to prefer Metopium fruits to other species. Because pigeons do not supplement nestling diets with arthropods, but augment their diets with protein-rich crop milk, they may depend on lipid-rich fruits such as Metopium to provide the energy for breeding and crop-milk production. Metopium fruit production may be influenced by rainfall and climatic conditions, both of which may vary spatially within the range of White-crowned Pigeons in Florida. Evidence that pigeons shift foraging sites when Metopium availability varies emphasizes the need to preserve large tracts of seasonal deciduous forest in the Keys and to protect Metopium trees in suburban areas where they are removed because they cause contact dermatitis in humans.

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Occurrence and relative abundance of mosquitoes in stormwater retention facilities in North Carolina, USA

Water Science & Technology ◽

10.2166/wst.2006.625 ◽

2006 ◽

Vol 54 (6-7) ◽

pp. 315-321 ◽

Cited By ~ 14

Author(s):

W.F. Hunt ◽

C.S. Apperson ◽

S.G. Kennedy ◽

B.A. Harrison ◽

W.G. Lord

Keyword(s):

North Carolina ◽

Relative Abundance ◽

Seasonal Changes ◽

Stormwater Management ◽

Biological Diversity ◽

Mosquito Species ◽

Structural Complexity ◽

Different Types ◽

Retention Structures ◽

Stormwater Retention

Throughout the 2004 mosquito season, 52 stormwater retention facilities were sampled to characterize the seasonal occurrence and relative abundance of mosquito species in relation to the structural complexity and biological diversity of the facilities. The three different types of facilities included standard wet ponds (n=20), innovative ponds (n=14), and wetland ponds (n=18). All retention structures were sampled at the beginning, middle and end of the mosquito season so that seasonal changes in mosquito production could be characterized. Overall samplings, mosquitoes were collected from 34% of the retention structures. Fourteen species representing 7 genera were collected, but only 5 species (Culex erraticus, Cx. territans, Anophelesquadrimaculatus, An. punctipennis and Uranotaenia sapphirina) were commonly collected in all three types of stormwater management facilities. In general, the seasonal prevalence and relative abundance of mosquito species did not vary among three types of retention structures. A significant association (P<0.01) between the presence of mosquito larvae or pupae and the absence of mosquitofish was found for innovative and wetland stormwater retention facilities but not for standard retention facilities (P>0.05).

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Biometrics as a determinant of the origins of seabirds killed in oil spills and other incidents

Bird Conservation International ◽

10.1017/s0959270908000233 ◽

2008 ◽

Vol 18 (3) ◽

pp. 229-241 ◽

Cited By ~ 2

Author(s):

Robert T. Barrett ◽

Tycho Anker-Nilssen ◽

Vidar Bakken ◽

Hallvard Strøm ◽

Yuri Krasnov ◽

...

Keyword(s):

Breeding Season ◽

Oil Spills ◽

Russian Population ◽

Systematic Variation ◽

Critically Endangered ◽

Body Measurements ◽

Reasonable Accuracy ◽

Norwegian Population ◽

Brunnich’S Guillemot ◽

Made In

AbstractCommon Guillemots Uria aalge and Brünnich's Guillemots U. lomvia are common victims of oil spills, drowning in fishing nets and winter wrecks. Because the Norwegian population of Common Guillemots is classified as critically endangered and the Russian population of the Brünnich's Guillemot has declined greatly, it is important to be able to identify the origins of birds killed outside the breeding season. Measurements of birds made in nine colonies in the Barents and Norwegian Seas showed that although it is impossible to determine with reasonable accuracy the colony of origin from body measurements, the most likely sea of origin of Common Guillemots may be determined on the basis of wing and head + bill lengths, whereas there was no systematic variation in any measurement of Brünnich's Guillemots.

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Testicular expression of NGF, TrkA and p75 during seasonal spermatogenesis of the wild ground squirrel (Citellus dauricus Brandt)

European Journal of Histochemistry ◽

10.4081/ejh.2015.2522 ◽

2015 ◽

Vol 59 (3) ◽

Cited By ~ 6

Author(s):

H. Zhang ◽

Y. Wang ◽

J. Zhang ◽

L. Wang ◽

Q. Li ◽

...

Keyword(s):

Breeding Season ◽

Sertoli Cells ◽

Seasonal Changes ◽

Ground Squirrel ◽

Leydig Cells ◽

Testicular Function ◽

Nonbreeding Season ◽

Function Change ◽

The Mean ◽

Neuronal Systems

The nerve growth factor (NGF) not only has an essential effect on the nervous system, but also plays an important role in a variety of non-neuronal systems, such as the reproductive system. The aim of this study was to investigate the seasonal changes in<strong> </strong>expression of NGF and its receptors (TrkA and p75) in testes of the wild ground squirrel during the breeding and nonbreeding seasons.<strong> </strong>Immunolocalization for NGF was detected mainly in Leydig cells and Sertoli cells in testes of the breeding and nonbreeding seasons. The immunoreactivity of TrkA was highest in the elongated spermatids, whereas p75 in spermatogonia and spermatocytes in testes of the breeding season. In the nonbreeding season testes, TrkA showed positive immunostainings in Leydig cells, spermatogonia and primary spermatocytes, while p75 showed positive signals in spermatogonia and primary spermatocytes. Consistent with the immunohistochemical results, the mean mRNA and protein level of NGF and TrkA were higher in the testes of the breeding season, and then decreased to a relatively low level in the nonbreeding season. In addition, the concentration of plasma gonadotropins and testosterone were assayed by radioimmunoassay (RIA), and the results showed a significant seasonal change between the breeding and nonbreeding seasons. To conclude, these results of this study provide the first evidence on the potential involvement of NGF and its receptor, TrkA and p75 in the seasonal spermatogenesis and testicular function change of the wild ground squirrel.

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Oestrous activity in three subtropical sheep breeds in Upper Egypt and response to long-day light treatment

The Journal of Agricultural Science ◽

10.1017/s0021859600076243 ◽

1991 ◽

Vol 116 (1) ◽

pp. 139-143 ◽

Cited By ~ 5

Author(s):

A. M. Aboul-Naga ◽

H. Mansour ◽

M. B. Aboul-Ela ◽

M. T. Mousa ◽

Ferial Hassan ◽

...

Keyword(s):

Breeding Season ◽

Seasonal Changes ◽

Nile Delta ◽

Reproductive Activity ◽

Light Treatment ◽

Continuous Exposure ◽

Upper Egypt ◽

Sheep Breeds ◽

Awassi Sheep ◽

Long Day

SUMMARYOestrous activity in local Rahmani and Ossimi sheep and imported subtropical Awassi sheep at different times of the year in Upper Egypt and the effect of continuous exposure to long-day conditions from July till December on this activity was studied in 1986. The three breeds differed substantially in oestrous activity but differences did not seem to be directly related to latitude of origin. Rahmani ewes from the Nile Delta were mostly cyclic all year round; the percentage coming to oestrus each month never fell below 70%. Ossimi ewes originating from mid-Egypt had a very long breeding season; 74% had an anoestrous period of 68·8 days (v. 27% for Rahmani ewes). All Awassi ewes, except one, had an anoestrous period of 96·5 days on average.Awassi ewes also showed more response to continuous exposure to long days (14 h) than Ossimi ewes, seen in a shorter reaction interval and a greater decrease in the percentage of ewes coming into oestrus (27 and 90% in control and treated Awassi ewes, respectively). The results indicated that changes in daylength, although small in subtropical regions, may be a major factor controlling seasonal changes in reproductive activity in subtropical sheep breeds, the more seasonal breed being more responsive to changes in daylength. The possibility of selection within these breeds for continuous reproductive activity is also indicated.

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Seasonal Distribution and Abundance of Dugongs in the Western-Gulf-of-Carpentaria

Wildlife Research ◽

10.1071/wr9890141 ◽

1989 ◽

Vol 16 (2) ◽

pp. 141 ◽

Cited By ~ 7

Author(s):

P Bayliss ◽

WJ Freeland

Keyword(s):

Relative Density ◽

Relative Abundance ◽

Coastal Waters ◽

Seasonal Changes ◽

Aboriginal People ◽

Dry Season ◽

Seasonal Distribution ◽

Wet Season ◽

Aerial Surveys ◽

The 1960S

Aerial surveys of coastal waters (27 216 km2) in the western Gulf of Carpentaria during the dry season of 1984 and wet season of 1985 indicated no major seasonal changes in distribution and relative abundance of dugongs. Minimum population size in the dry season was estimated as 16 816 � 2946 (standard error), with a relative density of 0.62 k 0.11 km-2, and that for the wet season 16 846 + 3257, with a relative density of 0.62 � 0.12 km-2. The estimates exclude 5% of observations which could have been either dugongs or Irrawaddy dolphins, and were corrected for submerged dugongs and those missed on the surface. Dugongs were unevenly distributed over the study area, and neither mean group size nor proportion of calves varied between seasons. Dugong abundance was correlated with area of available seagrass. The catch rate of dugongs by Aboriginal people off Numbulwar decreased six-fold between the 1960s and 1985 (60 to 10 p.a.), possibly due to excessive hunting.

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Reproductive Biology and Development of the Water Rat, Hydromys chrysogaster, in Captivity

Wildlife Research ◽

10.1071/wr9820039 ◽

1982 ◽

Vol 9 (1) ◽

pp. 39 ◽

Cited By ~ 2

Author(s):

PD Olsen

Keyword(s):

Breeding Season ◽

Developmental Stages ◽

Post Partum ◽

Growth Curves ◽

Gestation Length ◽

Body Measurements ◽

Sperm Production ◽

Crown Rump Length ◽

Rate Of Increase ◽

Hydromys Chrysogaster

In a captive colony of H. chrysogaster most litters were born between September and March, although some were born in every month except June. Most females had regular oestrous cycles in the breeding season but there were isolated instances of oestrus in every month. In mature males, testes were scrota1 and there was full sperm production all year. There was some regression in weight of male accessory reproductive glands in the autumn and winter. Oestrus lasted 10 days (range 7-17), and its stages: pro-oestrus 1 day, oestrus 2 days, metoestrus 2 days, anoestrus 5 days. Some instances of delayed implantation were suspected. Gestation length was 34 days (33-41). Parturition was followed the next day by a postpartum oestrus, lasting 1 day. Lactation anoestrus was at least 3 weeks. Litter size was 3.29 � 1.26 (1-7) and the number of litters per breeding season was 2.6 � 0.97 (1-5). In the latter half of pregnancy there was a linear relationship between the crown-rump length of foetuses and gestation length. Young were born naked, blind and with the pinnae folded forward with edges attached to the head. The upper incisors emerged at 4 days, the lower incisors at 6 days, the auditory meatus opened at about 10 days, the eyes opened at about 14 days, some solids were eaten and young were more independent at about 3 weeks of age, and they were weaned at about 29 days. Phases in the rate of increase in weight were associated with each of these developmental stages. Females were first capable of breeding at 124 days (433 g); most matured about 240 days in the season following that of their birth. The testes descended in males between 90 and 120 days (475 g) but full sperm production did not occur until about 130-140 days. Females could breed for three seasons (until about 3.5 y old). Placental scars were visible for up to 6 months, but had sometimes disappeared at 4 months post partum. Growth curves of tail and weight were sigmoid, and those of other body measurements were exponential, as in the Rattus group of Australian rodents, and differing from the pseudomyine rodents. Body measurements showed a sigmoid relationship to the linear equivalence of body weight. Developmental events occurred earlier, in relation to growth, in Hydromys and Rattus lutreolus than in Pseudomys novaehollandiae.

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