Seasonal changes in abomasal worms (Ostertagia spp.) in white-tailed deer (Odocoileus virginianus) at Long Point, Ontario

1975 ◽  
Vol 53 (1) ◽  
pp. 87-96 ◽  
Author(s):  
Michael R. Baker ◽  
Roy C. Anderson
Keyword(s):  
Odocoileus Virginianus ◽  
Seasonal Changes ◽  
Abundant Species ◽  
Early Spring ◽  
Host Age ◽  
Fourth Stage ◽  
Domesticated Animals ◽  
Grazing Season

Three species of nematodes were recovered from the abomasa of white-tailed deer (Odocoileus virginianus) collected at Long Point, Ontario, from September 1972 to August 1973. Ostertagia odocoilei was recovered from 45 deer (96%), O. mossi from 31 (66%), and O. dikmansi from 30 (64%). Abundance of adult stages of all three species was greatest in summer and least in winter. O. odocoilei was the most abundant species, especially during winter. Females were more abundant than males at all times of the year, particularly during winter.Numerous inhibited early fourth-stage larvae were recovered during winter and early spring, while few were found in July and August. The decrease in numbers of inhibited larvae in spring was coincident with a corresponding increase in abundance of adult worms. This is the first indication of the existence of inhibition (previously reported in domesticated animals) in species of Ostertagia parasitizing deer. Inhibition was not related to host age, indicating that the phenomenon is probably not due to development of immunity by the host over the grazing season.

Preliminary observations on seasonal changes in prevalence and intensity of Cosmocercoides variabilis (Nematoda: Cosmocercoidea) in Bufo americanus (Amphibia)

1987 ◽  
Vol 65 (7) ◽  
pp. 1666-1667 ◽  
Author(s):  
Daryl J. Vanderburgh ◽  
R. C. Anderson
Keyword(s):  
Seasonal Changes ◽  
Early Spring ◽  
Fourth Stage ◽  
Bufo Americanus

Individuals of Bufo americanus were examined from April to October for the presence of Cosmocercoides variabilis (Harwood, 1930) Travassos, 1931. Fourth-stage larvae were present in lungs in late April to early May. Larvae found in lungs in spring migrated to the rectum and matured by the end of May. Transmission of C. variabilis probably occurs throughout the season. Larval and adult worms encountered in toads in early spring were probably acquired the previous year.

scholarly journals Sheep nemabiome diversity and its response to anthelmintic treatment in Swedish sheep herds

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Peter Halvarsson ◽  
Johan Höglund
Keyword(s):  
Species Richness ◽  
Diversity Index ◽  
Nematode Species ◽  
Abundant Species ◽  
Anthelmintic Treatment ◽  
Host Age ◽  
Larval Culture ◽  
Nematode Parasites ◽  
South Central ◽  
Nematode Diversity

Abstract Background A novel way to study the species composition and diversity of nematode parasites in livestock is to perform deep sequencing on composite samples containing a mixture of different species. Herein we describe for the first time the nematode community structures (nemabiomes) inhabiting Swedish sheep and how these are/were affected by host age and recent anthelmintic treatments. Methods A total of 158 fecal samples were collected (n = 35 in 2007 and n = 123 in 2013–2016) and cultured from groups of sheep on 61 commercial farms in the south-central part of the country where most animals are grazed. Among the samples, 2 × 44 (56%) were paired collections from the same groups pre- and post-treatment with anthelmintics such as macrocyclic lactones, benzimidazoles or levamisole. Samples were analyzed for their nemabiome using the PacBio platform followed by bioinformatic sequence analysis with SCATA. Species richness and diversity were calculated and analyzed in R. Results Nematode ITS2 sequences were found in all larval culture samples except two, even though the fecal egg counts were below the McMaster threshold in 20 samples. Sequencing yielded, on average, 1008 sequences per sample. In total, 16 operational taxonomical units (OTU), all with ≥ 98 % identity to sequences in the NCBI database, were recognized. The OTUs found represented nematode species of which ten are commonly associated with sheep. Multiple species were identified in all pre-anthelmintic treatment larval culture samples. No effects on nematode diversity were found in relation to host age. On the other hand, recent anthelmintic treatment lowered species richness, especially after use of ivermectin and albendazole. Interestingly, despite zero egg counts after use of levamisole, these samples still contained nematode DNA and especially H. contortus. Conclusions Our findings provide evidence that nemabiome analysis combined with diversity index analysis provides an objective methodology in the study of the efficacy of anthelmintic treatment as both high and low abundant species were detected.

Seasonal changes in serum thyroid hormone levels in ruffed grouse maintained under natural conditions of temperature and photoperiod

1979 ◽  
Vol 57 (10) ◽  
pp. 2022-2027 ◽  
Author(s):  
A. Garbutt ◽  
J. F. Leatherland ◽  
A. L. A. Middleton
Keyword(s):  
Thyroid Hormone ◽  
Seasonal Changes ◽  
Gonadal Development ◽  
Early Spring ◽  
Light Period ◽  
Ruffed Grouse ◽  
Natural Conditions ◽  
Blood Samples ◽  
Serum Thyroid Hormone ◽  
Thyroid Hormone Levels

Serum triiodothyronine (T3) and thyroxine (T4) concentrations were measured in a population of ruffed grouse, held outdoors under natural conditions of photoperiod and temperature. Blood samples were collected at monthly intervals, and at the solstices and equinoxes to test for variation through the light period. No changes in T4 or T3 levels were found during the light period but levels of T3 and T4 showed marked seasonal changes. Lowest T4 and T3 levels were found in birds during the winter months, with an increase in the concentration of both hormones in early spring concomitant with gonadal development in the adults. A lowering of serum T4 and T3 values was associated with the period of molt.

scholarly journals Fish assemblages in a tidal flat

2003 ◽  
Vol 46 (2) ◽  
pp. 233-242 ◽  
Author(s):  
Ana Lúcia Vendel ◽  
Sabine Granado Lopes ◽  
César Santos ◽  
Henry Louis Spach
Keyword(s):  
Cluster Analysis ◽  
Community Structure ◽  
Tidal Flat ◽  
Seasonal Changes ◽  
Dominant Species ◽  
Fish Assemblages ◽  
Seasonal Pattern ◽  
Abundant Species ◽  
Structure Index ◽  
Total Capture

Studies were carried out on fish assemblages in a tidal flat. Samples were obtained monthly at low tide of the half moon in the tidal flat of Paranaguá Bay, Brazil, with two seine nets, one with a 1 mm mesh, 30 m in length and 3 m in height and another with a 10 mm mesh, 65 m in length and 2 m in height. A total of 8,890 fish were captured, comprising 24 families and 53 species. The most abundant species were Harengula clupeola and Atherinella brasiliensis, which represented 63.4% of the total, capture. A seasonal tendency was observed in the abundance of fishes, with less fishes being captured during winter and part of spring. The number of species showed a seasonal pattern, with the gradual decrease through winter and a marked increase in summer. The community structure index indicated seasonal changes in the assemblage. The faunistic similarities between months separated the 12 months into four major groups. The seasonal pattern was apparent in the numerically dominant species and the Cluster Analysis revealed five main groups.

Seasonal changes in concentrations of plasma hormones in the male ring dove (Streptopelia risoria)

1986 ◽  
Vol 108 (3) ◽  
pp. 385-391 ◽  
Author(s):  
R. W. Lea ◽  
P. J. Sharp ◽  
H. Klandorf ◽  
S. Harvey ◽  
I. C. Dunn ◽  
...  
Keyword(s):  
Seasonal Changes ◽  
Plasma Corticosterone ◽  
Early Spring ◽  
Energy Requirements ◽  
Breeding Cycle ◽  
Plasma Prolactin ◽  
Winter Solstice ◽  
Natural Lighting ◽  
Short Day ◽  
Ring Dove

ABSTRACT Seasonal changes in concentrations of plasma LH, prolactin, thyroxine (T4), GH and corticosterone were measured in captive male ring doves exposed to natural lighting at latitude 56 °N. Plasma LH levels decreased steeply in autumn when the daylength fell below about 12·5 h but increased in November as the birds became short-day refractory. In comparison with plasma LH concentrations in a group of short-day refractory birds exposed to 6 h light/day from the winter solstice, plasma LH levels in birds exposed to natural lighting increased further in spring after the natural daylength reached about 12·5 h. There were no seasonal changes in plasma prolactin concentrations and plasma T4 concentrations were at their highest during December, January and February, the coldest months of the year. The seasonal fall in plasma LH levels in September was associated with a transitory increase in plasma T4, a transitory decrease in plasma corticosterone and a sustained increase in plasma GH. It is suggested that in the ring dove, short-day refractoriness develops rapidly in November to allow the bird to breed when the opportunity arises, during the winter and early spring. The annual breeding cycle is synchronized by a short-day induced regression of the reproductive system in the autumn, the primary function of which may be to enable the birds to meet the energy requirements for the annual moult. The changes in plasma T4, corticosterone and especially of GH at this time of year are probably concerned with the control of moult or the associated changes in energy requirements. J. Endocr. (1986) 108, 385–391

The reproductive cycle of the viviparous seaperch, Cymatogaster aggregata Gibbons

1968 ◽  
Vol 46 (6) ◽  
pp. 1221-1234 ◽  
Author(s):  
John P. Wiebe
Keyword(s):  
Oocyte Maturation ◽  
Reproductive Cycle ◽  
Sertoli Cells ◽  
Reproductive Behavior ◽  
Seasonal Changes ◽  
Environmental Temperature ◽  
Interstitial Cells ◽  
Early Spring ◽  
Seminiferous Tubules ◽  
Male And Female

The natural reproductive cycle of male and female Cymatogaster aggregata is described with reference to gametogenesis, development of secondary sex structures, reproductive behavior, and gestation. Spermatocytogenesis starts in early spring and by June or July clusters of spermatozoa fill the seminiferous tubules. Concurrently the Sertoli cells and interstitial cells of Leydig increase in size and secondary sex structures develop on the male anal fin. When the sexes mingle in summer, the males perform very elaborate reproductive behavior. Fertilization occurs about mid-December—5 months after mating—and the ovary is then modified to maintain the young embryos until parturition in mid-summer. Oocyte formation is highest in July and August, just after parturition, while vitellogenesis and oocyte maturation occur mainiy from October to December. These seasonal changes are discussed in relation to changes in environmental temperature and photoperiod.

Seasonal changes in louse populations on white-tailed deer (Odocoileus virginianus)

1975 ◽  
Vol 53 (8) ◽  
pp. 1047-1054 ◽  
Author(s):  
Thomas G. Watson ◽  
Roy C. Anderson
Keyword(s):  
Environmental Factors ◽  
Solar Radiation ◽  
Head And Neck ◽  
Odocoileus Virginianus ◽  
Seasonal Changes ◽  
Radiation Temperature ◽  
Upper Body ◽  
Immature Stages ◽  
Body Regions ◽  
Biting Lice

The hides of 47 white-tailed deer (Odocoileus virginianus) shot at Long Point, Ontario, between September 1972 and August 1973 were examined for lice. Adult Tricholipeurus lipeuroides were most abundant from January to April and T. parallelus from May to August. The distributions of biting lice changed over the study period, possibly influenced by environmental factors such as solar radiation, temperature, rainfall, and changes in pelage. Solenopotes ferrisi was found throughout the study period. There was no significant change in abundance of the various louse stages throughout the study, although all stages were slightly more numerous during winter. Adults primarily infested the head and neck, while immature stages infested upper body regions. Changes in distribution of lice may be the result of environmental and host pelage changes.

Productivity of S. 59 red fescue with and without S. 184 white clover under hill conditions: 1. Animal performance

1975 ◽  
Vol 84 (2) ◽  
pp. 265-272 ◽  
Author(s):  
D. A. Davies
Keyword(s):  
White Clover ◽  
Growth Rates ◽  
Live Weight ◽  
Early Spring ◽  
Individual Growth ◽  
Grazing Season ◽  
Red Fescue ◽  
Significant Difference ◽  
Weight Gains ◽  
Second Year

SUMMARYAn appraisal of the value of S. 59 red fescue (Festuca rubra L.) for grazing was made using ewes and lambs (Clun Forest in 1969, Welsh Mountain in 1970) at a site 305 m O.D. in mid-Wales. S. 23 perennial ryegrass (Lolium perenne L.) was used as a control, and the value of S. 184 white clover (Trifolium repens L.) in conjunction with both grasses was examined.In the first year, under a rotational grazing regime at a fixed stocking rate of 22 ewes and single lambs/ha, lamb live-weight gains were significantly poorer on S. 59/S. 184 and significantly better on S. 23/S. 184 than on either of the pure grass swards. For the 130 days grazing season, mean daily lamb live-weight gains were 157, 126, 78 and 120 g on S. 23/S. 184, S. 23, S. 59/S. 184 and S. 59 treatments respectively.During the second year lamb growth rates on S. 59/S. 184 improved by 59%, whereas those on the other treatments were marginally lower than in 1969. Stocking rates were increased on the grass swards and decreased on the grass/clover swards for most of the grazing period in the second year in accordance with herbage availability. No significant difference was detected between the four treatments in total lamb liveweight production as a result of better individual growth rates on the grass/clover swards.In both years wide variations were recorded between treatments at different periods within the grazing season. Red fescue swards maintained superior lamb production in early spring and late autumn, but were inferior to ryegrass in mid-summer.

The effect of plane of nutrition and shearing on the pattern of the moult in Scottish Cashmere goats

2002 ◽  
Vol 74 (1) ◽  
pp. 177-188 ◽  
Author(s):  
M. Merchant ◽  
D.J. Riach
Keyword(s):  
Seasonal Changes ◽  
Early Spring ◽  
Energy Requirements ◽  
Plasma Prolactin ◽  
Length Data ◽  
Cashmere Goats ◽  
Ad Libitum ◽  
Maintenance Requirements ◽  
Circulating Levels ◽  
Staple Length

AbstractThe effect of plane of nutrition on the timing of the moult in cashmere goats was investigated. Three groups of mature does were individually offered food to supply 0·8 (L, no. = 14), 1·2 (M, no. = 14) or 20 (H, no. = 13) times their estimated maintenance energy requirements from mid December until mid May. Two other groups of goats which were shorn in mid January, were offered 1·2 times maintenance requirements from mid December until mid March when food levels were increased to either 1·6 M (SL, no. = 6) or ad libitum (SAL, no. = 6). In mid May mean live weights for treatments L, M, H, SL and SAL were 36·0, 41·5, 46·9, 33·0 and 43·1 kg (average s.e.d. = 2·27, P < 0·001).The pattern of moult was described by changes in a subjectively assessed moult score, the proportion of follicles with brushes and staple length. The loss of brushes, indicating the start of the moult, began from the primary follicles on days 143, 131, 76, 150 and 129 (average s.e.d. = 13·5, P < 0001), and from the secondary follicles on days 141, 128, 104, 144 and 125 (average s.e.d. = 14·1, P = 0·053) for treatments L, M, H, SL and SAL respectively. The loss of brushes from primary and secondary follicles was completed on average, by days 194 and 206 of the experiment respectively, and there were no differences between treatments. Moult score and staple length data confirmed the conclusion that lowering the plane of nutrition delayed the start of the moult. No additional effect of fleece removal in the shorn treatments was observed.Changes in circulating levels of plasma prolactin, thyroxine, tri-iodothyronine, insulin, insulin-like growth factor-1 and growth hormone were related to seasonal changes in daylength and plane of nutrition. Their rôle in the control of the moult is discussed.Manipulation of the nutrition of cashmere goats in early spring has the potential to delay and increase the synchrony of fibre moult and to improve the efficiency of cashmere harvesting.

Sign in / Sign up

Export Citation Format

Share Document