A Comparison of Growth-Rates in Dependent Juveniles of Planigale-Gilesi and Planigale-Tenuirostris (Marsupialia, Dasyuridae)

1987 ◽  
Vol 35 (2) ◽  
pp. 161 ◽  
Author(s):  
DG Read
Keyword(s):  
Community Structure ◽  
Linear Regression ◽  
Body Condition ◽  
Growth Rates ◽  
Developmental Stages ◽  
Early Weaning ◽  
Body Sizes ◽  
Eye Opening ◽  
Body Parameters ◽  
Similar Growth

Growth rates are compared from birth to early weaning in Planigale gilesi and P. tenuirostris, by means of linear regression of body parameters plotted against age. Pouch young of each species had similar growth rates; an equation is given for the aging of pouch young of P. gilesi. Juveniles of P. gilesi grew faster than those of P. tenuirostris; in both species there was a trend for males to grow faster than females. Eye opening and the end of weaning were two important developmental stages, associated with changes to reduced growth rates. Changes in body condition of the juveniles indicated that the weaning process was initiated by the mother. The different growth rates between the species and sexes produced a range of body sizes in juveniles at independence. This has important implications for partitioning of food and for community structure.

Phenotypic differences among wild passerine nestlings in relation to early-life rearing environment

2021 ◽  
Author(s):  
Jesús Gómez ◽  
Christy Morrissey ◽  
Sonia Cabezas ◽  
Tracy Marchant ◽  
Robert Clark
Keyword(s):  
Land Use ◽  
Body Condition ◽  
Early Life ◽  
Agricultural Land ◽  
Developmental Stages ◽  
Tree Swallow ◽  
Phenotypic Differences ◽  
Aerial Insectivore ◽  
Fledgling Survival ◽  
Insect Populations

Subtle changes in stress physiology during critical developmental stages have been linked to long-term fitness; however, the biological processes and phenotypic responses to early-life rearing environments such as anthropogenic land use conditions, have not been fully evaluated in insectivorous birds. We manipulated Tree Swallow, Tachycineta bicolor (Vieillot, 1808), brood sizes at sites with contrasting agricultural land use to assess phenotypic changes in body condition and genetic and physiological biomarkers of stress during the sensitive nestling growth phase. We predicted that nestling swallows raised on cropland-dominated sites, especially those in enlarged broods, would have lower body condition, shorter telomeres, and higher feather corticosterone than nestlings raised in smaller broods at grassland sites. Body condition was highest among nestlings raised in reduced broods but was unrelated to land use. Telomere lengths tended to be shorter in nestlings from enlarged broods and at cropland sites. Corticosterone was not related to any factor. Locally-abundant insect populations associated with wetlands may have dampened the effects and/or parent swallows assumed higher costs of reproduction rather than passing these costs to nestlings. Results suggest that food stress could reduce fledgling survival via telomere shortening; a hypothesis that requires further investigation due to its potential importance to population viability in multiple declining aerial insectivore species.

A STUDY OF RATES OF GROWTH OF YORKSHIRE, LACOMBE, LANDRACE, AND CROSSBRED PIGS FROM BIRTH TO 200 LB

1964 ◽  
Vol 44 (3) ◽  
pp. 315-319
Author(s):  
J. M. Bell
Keyword(s):  
Growth Rates ◽  
Early Life ◽  
Growth Curves ◽  
Rates Of Growth ◽  
Similar Growth ◽  
Crossbred Pigs

Growth records were obtained from 12 research establishments across Canada for pigs fed according to current (1960–63) recommendations of nutrition and management. Growth curves showing age in days and weight in pounds are presented for the various breeds and crossbreds, for between-station comparisons, for comparison of upper and lower quartiles in purebred pigs, and for comparison of growth rates of purebreds with that of Yorkshires of 20 to 25 years ago.Age at 200 lb averaged from 152 to 187 days, among 10 stations for the Yorkshire breed. Pigs of each of the pure breeds reached 200 lb about 3 weeks earlier than that indicated in previous studies. Crossbred pigs of each of four different crosses grew more rapidly than average Yorkshires, some reaching 200 lb in 140 days and having gains in excess of 2.3 lb/day during the finishing period. Yorkshire, Lacombe, and Landrace pigs had similar growth curves. The upper quartile averaged 1.8 and the lower 1.4 lb/day gain between 100 and 200 lb weights. Slow-maturing pigs tended to be below average throughout life but differences in maturity between stations seemed to reflect differing rates of gain in early life, since finishing period gains were similar in 8 of 10 stations.

scholarly journals Seasonal maturation of Glypthelmins vitellinophilum (Trematoda: Digenea) in Lysapsus limellus (Anura: Pseudidae) from an Argentinian subtropical permanent pond

2006 ◽  
Vol 66 (1a) ◽  
pp. 85-93 ◽  
Author(s):  
M. I. Hamann
Keyword(s):  
Body Length ◽  
Developmental Stages ◽  
Small Body ◽  
Stage Iv ◽  
The Body ◽  
Climatic Fluctuations ◽  
Parasite Stage ◽  
Permanent Pond ◽  
Body Sizes ◽  
The Relationship

From December 1995 to November 2000, the seasonal maturation of Glypthelmins vitellinophilum Dobbin, 1958, in its definitive host, the frog Lysapsus limellus Cope, 1862, was studied in a subtropical permanent pond in northeastern Argentina. The objectives of this study were: 1) to determine the infrapopulation dynamics of the parasite, analyzing the seasonal maturation cycle throughout the years; and 2) to examine the relationship between the intensity of trematode infection in different developmental stages (recruitment, growth and maturation) and the host's body length. Of a total of 1,400 frogs examined over 60 months (5 years), 38% were found to be infected with G. vitellinophilum, and the intensity of infection was 1-15 trematodes per frog. Specimens of G. vitellinophilum were present in L. limellus throughout the years, but did not show a pronounced seasonal maturation cycle. Possible reasons for these findings are discussed with reference to climatic fluctuations and biotic factors. The infective period of the parasite (stage I) occurred in summer, autumn and spring, coinciding with the time each frog cohort appeared. These infections were found principally in small body sizes (classes 1 and 2) of L. limellus. Juvenile and nongravid specimens of worms (stage II and III) were found in frogs of different body sizes throughout the period of investigation. Gravid specimens of the parasite (stage IV) were generally recorded in autumn, winter and spring, mainly in the bodies of larger frogs. The body length of Trematodes in stages I and IV was significantly and positively correlated with that of the frogs.

scholarly journals THE ANALYSIS OF OIL CONTENT IN SEDIMENT AND COMMUNITY STRUCTURE OF MACROZOOBENTHOS IN BELAWAN WATERS OF MEDAN CITY, NORTH SUMATERA PROVINCE

2020 ◽  
Vol 3 (2) ◽  
pp. 167-178
Author(s):  
Doli Juna Setia Tanjung ◽  
Bintal Amin ◽  
Syafruddin Nasution
Keyword(s):  
Community Structure ◽  
Linear Regression ◽  
Oil Content ◽  
Diversity Index ◽  
The Other ◽  
Regression Analyses ◽  
Simple Linear Regression ◽  
Dominance Index ◽  
Ocypode Quadrata ◽  
Evenness Index

This research was conducted in March 2019 to determine the oil content in sediment, it’s community structure of macrozoobenthos and it’s a relationship in Belawan Waters of Medan City, North Sumatera. Four sampling stations with five replications in each station were surveyed. The results showed that the average oil content in sediments exceeded the threshold had set by the National Academy of Science. Macrozoobenthos found consists of Ocypode quadrata, Scyla serrate, Rotun dicauda, Penaeus sp, Murex tribulus, and Nassarius olivaccus. The highest abundance was in Station 3 and the lowest was in Station 2. The diversity index in each station was generally very low. Dominance Index in Station 4 was medium, whilst the other stations were high. Evenness index showed in Station 3 and 4 were in high population, Station 1 was in medium population and Station 2 was in low population. Simple linear regression analyses between oil content in sediment with community structure of macrozoobenthos indicated negative correlation ( Y = 10,5-0,0001x , R2 = 0,0004 and r = 0,02 ) which indicated that the higher the oil content, the lower the macrozoobenthos abundance in sediment.

Effects of Truttaedacnitis truttae (Nematoda: Cucullanidae) on growth and swimming of rainbow trout, Salmo gairdneri

1980 ◽  
Vol 58 (7) ◽  
pp. 1220-1226 ◽  
Author(s):  
L. R. Russell
Keyword(s):  
Rainbow Trout ◽  
Growth Rates ◽  
Growth Characteristics ◽  
Salmo Gairdneri ◽  
Food Conversion ◽  
Critical Swimming Speed ◽  
Nematode Parasites ◽  
Conversion Efficiencies ◽  
Similar Growth ◽  
Food Consumed

Growth and swimming abilities of fingerling and 1.5-year-old rainbow trout infected with the nematode parasite Truttaedacnitis truttae were examined. Control trout and trout infected in the laboratory with 5, 10, 20, 40, or 80 worms exhibited similar growth characteristics over a 10-week period within each of four experimental groups fed different rations of trout chow (1, 2, 3, or 4% of wet body weight fed per day). Decreasing growth rates showed some correlation with increasing numbers of nematode parasites. Differences between growth rates, amounts of food consumed, and food conversion efficiencies of infected and noninfected fish were not statistically significant. Critical swimming speed, fixed velocity, and burst velocity stamina tests revealed similar swimming abilities in both control and infected trout. Maximum swimming speeds attained and time to fatigue at cruising speeds were more closely related to fish size than to numbers of worms with which fish were infected. Importance to rainbow trout survival of large natural infections with T. truttae is discussed.

scholarly journals Impact of Feed Rations on Growth, Selected Body Parameters and Maturation of Vendace, Coregonus Albula L., Reared in RAS

2014 ◽  
Vol 22 (2) ◽  
pp. 145-150
Author(s):  
Bożena Szczepkowska ◽  
Mirosław Szczepkowski ◽  
Iwona Piotrowska
Keyword(s):  
Growth Rates ◽  
Sexual Maturity ◽  
Fish Growth ◽  
Coregonus Albula ◽  
Body Weights ◽  
Intensive Rearing ◽  
Mature Fish ◽  
Final Survival ◽  
Body Parameters ◽  
Commercial Size

Abstract Vendace, Coregonus albula L., was reared to commercial size in a recirculating system. Three different feed rations were applied during the ten-month-long experiment. The feed rations impacted fish growth rates, and fish in the different groups achieved body weights of 26.6 g to 57.5 g. The final survival in all groups was similar from 44.3% among the fish fed the smallest feed ration to 53.2% in the group receiving the largest feed ration. No differences were noted in the share of viscera, peritoneal fat, or in the hepatosomatic indexes, but there were differences in the gonadosomatic indexes. After thermal stimulation, only males achieved sexual maturity. The number of mature fish was similar in all groups and ranged from 17.8 to 21.3% of all fish. The results of the present study indicated that vendace can achieve commercial size in an intensive rearing period of ten months in RAS.

An investigation of factors influencing erythrocyte morphology of red-backed salamanders (Plethodon cinereus)

2009 ◽  
Vol 59 (2) ◽  
pp. 201-209 ◽  
Author(s):  
John Maerz ◽  
Joseph Milanovich ◽  
Andrew Davis ◽  
Jayna DeVore
Keyword(s):  
Body Size ◽  
Body Condition ◽  
Oxygen Demand ◽  
Plethodon Cinereus ◽  
Future Research ◽  
Health State ◽  
Erythrocyte Morphology ◽  
Size And Shape ◽  
Plethodontid Salamanders ◽  
Body Sizes

AbstractAmphibians have long been known to display wide variation in erythrocyte morphology across species, but within species there has been little attention given to individual variation in red blood cell morphology. We captured 49 red-backed salamanders (Plethodon cinereus) from central Pennsylvania, USA and used image analysis procedures to measure erythrocyte morphology (size and shape) on blood smears made from all individuals. We then statistically examined whether variation in snout-vent-length, sex, tail loss, or capture location influenced these cell variables. Only snout-vent-length affected erythrocyte size and shape, with increasing body sizes associated with increasing cell areas and increasingly rounder cells. Further, erythrocyte shape was also associated with a measure of body condition that was corrected for body size, such that individuals with high body condition scores had rounder cells. Given the oxygen-carrying role of erythrocytes in all vertebrates, we suspect this discovery is related to size-related changes in oxygen demand, since total oxygen consumption increases with body size in an allometric manner. While our results warrant further investigation to understand the mechanism, the association we found between cell roundness and both body size and condition nevertheless indicates this parameter could be used to assess the health state of plethodontid salamanders in future research, provided non-destructive sampling is employed. Our results also underscore the value of hematological investigations in the study of animal biology.

The effects of components of body weight on reproductive efficiency in the Merino ewe

1972 ◽  
Vol 78 (2) ◽  
pp. 245-249 ◽  
Author(s):  
J. C. Guerra ◽  
C. J. Thwaites ◽  
T. N. Edey
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Linear Regression ◽  
Body Condition ◽  
Experimental Period ◽  
Ovulation Rate ◽  
Reproductive Efficiency

SUMMARYGroups of mature Merino ewes selected on the basis of either large or small bodysize were differentially fed during a pre-experimental period to produce subgroups of high and low body condition. These levels of body condition were maintained for 2 weeks before mating and for the first 5 weeks of gestation. Thereafter, the four subgroups grazed together until lambing.Big ewes had more multiple ovulations than small ewes (14/41 υ 6/53; P < 0·01), and there was a significant linear regression of ovulation rate on body size. Body condition was positively related to the incidence of multiple ovulations, but the regression of ovulation rate on body condition at mating failed to reach significance. Body weight was significantly related to both ovulation rate and the incidence of multiple ovulations, and proved to be a more effective predictor of ovulation rate than either body size or condition.These results make it clear that size and condition, the two components of body weight, each have a considerable independent influence on some aspects of reproduction, and that the precision of some experiments and the effectiveness of some production routines could be improved by considering them separately.

Reproductive dynamics of a turtle (Pseudemys scripta) population in a reservoir receiving heated effluent from a nuclear reactor

1970 ◽  
Vol 48 (4) ◽  
pp. 881-885 ◽  
Author(s):  
J. Whitfield Gibbons
Keyword(s):  
South Carolina ◽  
Growth Rates ◽  
Nuclear Reactor ◽  
Large Body ◽  
Reproductive Rate ◽  
Hot Water ◽  
Trophic Levels ◽  
Body Sizes ◽  
Pseudemys Scripta ◽  
Growth Differences

Individual yellow-bellied turtles (Pseudemys scripta) in Par Pond, a thermally polluted reservoir on the Savannah River Plant, Aiken, South Carolina, U.S.A., reach exceedingly large body sizes and maintain extraordinary juvenile growth rates when compared with turtles of this species from other populations in the vicinity. Increased water temperatures are not directly responsible for the observed size and growth differences. Diet differences resulting from increased productivity at lower trophic levels as a result of the hot-water effluent may be the cause of the observed growth and size phenomena. The increased growth rates and larger body sizes in the Par Pond turtles result in changes in reproductive rate which may have interesting consequences on the demography of the population.

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