Aspects of Reproduction in the Male Humpback Whale, Megaptera nodosa (Bonnaterre)

1955 ◽  
Vol 6 (1) ◽  
pp. 1 ◽  
Author(s):  
RG Chittleborough
Keyword(s):  
Body Length ◽  
Low Fertility ◽  
Humpback Whales ◽  
Testis Weight ◽  
Activity Increase ◽  
Penis Length ◽  
The Mean ◽  
Considerable Individual Variation ◽  
Sexually Mature ◽  
Average Body

At puberty, male humpback whales off the Western Australian coast have an average body length of 36 ft 9 in. From histological examination of the testes, the extreme range of lengths at puberty is from 33 ft 4 in. to 40 ft 10 in. The mean testis weight at puberty is 2000 g. Following puberty, males are of low fertility for a period (possibly 1 yr) during which testis weight, tubule diameter, and spermatogenetic activity increase, before the attainment of full sexual maturity. The mean length of the penis at puberty is 3.5 ft, but owing to considerable individual variation the penis length alone is not a reliable criterion of puberty. In sexually mature males the penis length ranges from 3.2 to 6.2 ft. The proportion of fully physically mature males amongst those examined was very low (1.4 per cent.). The mean body length of those defined in this paper as approaching physical maturity was 41.90 � 0.35 ft, and that of the fully physically mature males was 42.97 �1.59 ft. The largest male examined (46.42 ft) showed no sign of epiphysial fusion. Changes in mean testis weight, mean diameter of testis tubules, and number of sperms in testes and vas deferens fluid have been followed at various stages of the life cycle. The variations of these characters in mature individuals have been examined for evidence of a seasonal cycle in male humpback whales; increasing testis weight and more active spermatogenesis are exhibited during winter months off Western Australia.

Puberty, Physical Maturity, and Relative Growth of the Female Humpback Whale, Megaptera nodosa (Bonnaterre), on the Western Australian Coast

1955 ◽  
Vol 6 (3) ◽  
pp. 315 ◽  
Author(s):  
RG Chittleborough
Keyword(s):  
Body Length ◽  
Sexual Maturity ◽  
Humpback Whale ◽  
Humpback Whales ◽  
Relative Growth ◽  
Male And Female ◽  
The Mean ◽  
Sexually Mature ◽  
Western Australian

At puberty the mean body length of the female humpback whales on the Western Australian coast is 38.60 � 0.18 ft. It is demonstrated that this length gives a reliable means of calculating the proportion of sexually immature females in a series where the lengths are known. Sexual maturity (based upon the first pregnancy) may either follow immediately upon puberty or be delayed for a further year. At the approach of physical maturity (when epiphysial fusion begins) the mean body length is 45.08 � 0.29 ft. At this stage an average of 19 ovulations have occurred. On the available material, physical maturity is reached at a mean length of 44.34 � 0.72 ft, when close to 30 ovulations have occurred. Growth in body length of sexually mature females becomes very slow even before epiphysial fusion begins. The significance of the high number of ovulations before the attainment of physical maturity is discussed. The proportion of physically mature individuals amongst the females in recent catches off the Western Australian coast is extremely low (1.8 per cent. of 457 females examined). The lengths of male and female humpback whales at puberty, at the approach of physical maturity, and at physical maturity are compared.

Determination of Age in the Humpback Whale, Megaptera nodosa (Bonnaterre)

1959 ◽  
Vol 10 (2) ◽  
pp. 125 ◽  
Author(s):  
RG Chittleborough
Keyword(s):  
East Coast ◽  
Age Distribution ◽  
Age Determination ◽  
Humpback Whales ◽  
Similar Distribution ◽  
The West ◽  
The Mean ◽  
Sexually Mature ◽  
Rate Of Accumulation

The use of baleen, ear plugs, and ovaries in the determination of age in humpback whales is described. From the evidence of baleen, the majority of humpback whales reach puberty at 4 or 5 years of age. The rate of accumulation of laminations in ear plugs is two laminations per year. The mean rate of ovulation in sexually mature females is 1.1 per year. Age determination upon the same sample of mature females by these two methods gives very similar distribution of ages. The age distribution within separate sexes from samples of mature humpback whales examined on the west and east coasts of Australia in 1957 are compared. The results indicate that the population migrating along the west coast is at present composed of younger individuals than that on the east coast of Australia.

Morphometric and carcass characteristics of Jaunpuri breed of goats

2017 ◽  
Vol 36 (02) ◽  
Author(s):  
Dharmendra Kumar ◽  
V. K. Singh ◽  
Alok Kumar Yadav ◽  
Amit Kumar Jha ◽  
Jitendra Singh
Keyword(s):  
Body Length ◽  
Age Groups ◽  
Uttar Pradesh ◽  
Carcass Characteristics ◽  
Mean Value ◽  
Average Height ◽  
Body Weights ◽  
The Mean ◽  
Average Body Length ◽  
Average Body

The present study was undertaken to observe morphometric and carcass characteristics of Jaunpuri goat. The survey plan was conducted in two districts viz. Allahabad and Jaunpur of its native tracts in Uttar Pradesh. The overall average body weights of male goats of the age groups 0-3, 3-6, 6-9, 9-12 and above12 months were observed as 5.50±0.327, 12.07±0.598, 19.62±0.738, 21.92±0.571 and 30.44±0.978 kg respectively. The overall average body length of male goats of the age groups 0-3, 3-6, 6-9, 9-12, and above 12 months were observed as 38.63±1.762, 48.55±2.090, 58.77±0.652, 67.23±0.777 and 67.56±0.747 cm. The overall average height of male goats of the age groups 0-3, 3-6, 6-9, 9-12 and above 12 months were observed as 41.63±1.945, 53.36±2.094, 66.23±1.051, 72.69±0.664 and 72.31±0.893 cm, respectively. The corresponding values for females were 44.24±0.825, 50.38±0.836, 62.81±0.466, 69.14±0.387 and 69.00±0.691 cm. The mean value of horn size of male goats of the age groups 0-3, 3-6, 6-9, 9-12 and above 12 months were observed as 1.94±0.346, 2.73±0.449, 5.54±0.584,5.85±0.696 and 7.56±0.381 cm respectively. The respective averages for females were 1.77±0.171, 2.60±0.173, 4.94±0.322, 6.53±0.424 and 6.79±0.421 cm. The results revealed no significant differences in average slaughter weight between the sexes of the same age groups but it varied significantly (P less than 0.05) in different age groups like 6, 9 and 12 month of age.

Population parameters of ringed seals (Phoca hispida Schreber, 1775) in the Svalbard area

1987 ◽  
Vol 65 (4) ◽  
pp. 1021-1027 ◽  
Author(s):  
Christian Lydersen ◽  
Ian Gjertz
Keyword(s):  
Sex Ratio ◽  
Ringed Seal ◽  
Adult Males ◽  
Population Parameters ◽  
Phoca Hispida ◽  
Age Class ◽  
Ringed Seals ◽  
Males And Females ◽  
The Mean ◽  
Sexually Mature

Samples were taken from 284 ringed seals (Phoca hispida) in the Svalbard area during April–July 1981 and March–April 1982. The age of 283 seals was determined by reading annuli in the cementum of the canine teeth. The mean age of the males was 11.3 years, and of the females, 14.9 years. Females were found to be significantly older than males. The mean length of sexually mature ringed seals was 128.9 cm for both sexes. The mean weight of adult males and females was 53.5 and 61.4 kg, respectively. Females were found to be significantly heavier than males. The sex ratio was 47.8% males and 52.2% females. Studies of microscopic sections of testis and epididymis from ringed seal males showed that 63, 75, and 80% of 5-, 6-, and 7-year-old animals, respectively, were sexually mature. The weights of testis and epididymis, diameters of tubuli, and the size of testis all showed a marked increase in the 5-year age-class. Macroscopic sections of ovaries from ringed seal females showed that 20, 60, and 80% of 3-, 4-, and 5-year-old animals, respectively, were sexually mature. The size of the ovaries showed a marked increase in the 5-year age-class. The ovulation rate of ringed seals from Svalbard was calculated to be 0.91.

scholarly journals Movement patterns of humpback whales (Megaptera novaeangliae) reoccupying a Brazilian breeding ground

2018 ◽  
Vol 18 (4) ◽  
Author(s):  
Maria Isabel Carvalho Gonçalves ◽  
Renata Santoro de Sousa-Lima ◽  
Niel Nascimento Teixeira ◽  
Gustavo Henrique Carvalho ◽  
Daniel Danilewicz ◽  
...  
Keyword(s):  
Group Composition ◽  
Movement Patterns ◽  
Study Groups ◽  
Humpback Whales ◽  
Suitable Habitat ◽  
Behavioral State ◽  
Energy Conserving ◽  
Wintering Area ◽  
The Mean ◽  
Feeding Grounds

Abstract: The population of humpback whales from breeding stock A is increasing, and little is known about the routes used by humpbacks that move north of the main calving area of Brazil, the Abrolhos Bank. The aim of this study was to describe the movements of humpback whales in a reoccupation wintering area (Serra Grande, Bahia state, Brazil) based on land-based surveys to test if movement patterns change during the season and between years, due to group composition, behavioral state, and distance to the coast. The mean leg speed of the groups sighted was 6.88 (±2.92) km/h, and leg speed was positively correlated with distance to the coast. There was an increase in leg speed and distance to the coast with increasing number of escorts in the groups with calves. The mean linearity value for group trajectory was 0.81 (±0.19) and the mean reorientation rate was 25.72 (±19.09) º/min. We observed a predominance of trajectories heading south throughout the study. Groups exhibiting more erratic movements early in the season, and groups moving south showed more linear trajectories than groups moving north, indicating the beginning of their migration back to the feeding grounds. Energy conserving strategies and social context affect the movements of humpback whales in Serra Grande, resulting in the observed patterns of the reoccupation of available and suitable habitat north of Abrolhos. Thereby, special attention should be given managing activities with the potential to disturb or displace whales using the region to calve and breed.

scholarly journals REKONDISI BEBERAPA UKURAN TUBUH TERNAK SAPI PERAH FRIESS HOLLAND DI BALAI PENGEMBANGAN BIBIT DAN PAKAN TERNAK TAMPUSU

ZOOTEC ◽  
2019 ◽  
Vol 39 (1) ◽  
pp. 165
Author(s):  
Renaldo J. Maluhima ◽  
J.H. Manopo ◽  
A. Lomboan ◽  
S.H. Turangan
Keyword(s):  
Body Weight ◽  
Dairy Cattle ◽  
Seed Development ◽  
Body Length ◽  
Animal Feed ◽  
Chest Circumference ◽  
Descriptive Research ◽  
Body Sizes ◽  
Development Center ◽  
Average Body

COMPENSATORY CONDITION OF SEVERAL MEASURES IN FRIESS HOLLAND DAIRY CATTLE AT TAMPUSU ANIMAL FEED AND SEED DEVELOPMENT CENTER. This study was conducted to assess the compensatory condition of some body sizes of Friess Holland Dairy Cattle at Tampusu Animal Feed and Seed Development Center. Animals used in this study were 23 Friesian Fries Holland (FH) dairy cattle at aged of 7 months to 7 years old using a comparative descriptive research method by comparing the same variables for different samples and using the t-test. Research was done by measuring body weight, chest circumference, shoulder’s height and body length. The maintenance of animals was using a double cage head to head. Feeds given were using forages of 10% / head / day from body weight. Concentrate was fed about 2 kg / head / day. Dairy cows in Tampusu have an average body weight of 401.533 ± 39.47 Kg with a varince coefficient value of  9.8%, an average chest circumference of 174.12 ± 11.15 cm with a varience coefficient value of 6.4%, average shoulder height 136.47 ± 9.16 cm with a variance coefficient value of 6.7%, average body length 139.39 ± 9.56 vm with a variance coefficient of 6.8%. Based on these results, the compensatory condition friess holland dairy cattle at tampusu animal feed and seed development center was increase   body weight of 11.6%, chest circumference 6.28% and shoulder height of 6.65%. Keywords: Compensatory condition, body measurements, Friess Holland Dairy Cattle

FERTILITY OF BARLEY AUTOTETRAPLOIDS: I. FERTILITY IN SUCCESSIVE GENERATIONS OF FOUR AUTOTETRAPLOID BARLEY VARIETIES AND THE EFFECT OF SELECTION FOR FERTILITY IN THE O.A.C. 21 AUTOTETRAPLOID

1959 ◽  
Vol 39 (1) ◽  
pp. 98-107 ◽  
Author(s):  
E. Reinbergs ◽  
L. H. Shebeski
Keyword(s):  
Promising Method ◽  
Low Fertility ◽  
Fertility Level ◽  
Seed Setting ◽  
The Mean ◽  
Selection For ◽  
Successive Generations ◽  
Subsequent Selection

The differences in fertility of four colchicine-induced autotetraploid barley varieties (Brant, Montcalm, O.A.C. 21 and York) were determined and compared in four successive generations following the induction of tetraploidy. Despite a wide fertility range within each autotetraploid, the varieties tested varied considerably in their mean per cent fertility. Within each variety the mean per cent fertility remained relatively constant from generation to generation. The Montcalm tetraploid had the lowest mean fertility, fluctuating from generation to generation within a range of 6.0 to 10.1 per cent. The O.A.C. 21 tetraploid had the highest mean fertility, fluctuating within a range of 40.0 to 51.3 per cent.Significant differences in fertility of the four autotetraploid varieties were interpreted as indicating that seed-setting ability may be genetically controlled and, therefore, hybridization and subsequent selection could be a promising method for increasing fertility.Continuous selection for either high or low fertility from the C1 to C4 generation did not change the mean per cent fertility level in the O.A.C. 21 tetraploid.

A decadal study of biometric and imposex indices in two gastropods

2019 ◽  
Vol 99 (7) ◽  
pp. 1601-1614
Author(s):  
J. M. Ruiz ◽  
B. Carro ◽  
N. Albaina ◽  
L. Couceiro ◽  
M. Quintela ◽  
...  
Keyword(s):  
Vas Deferens ◽  
Shell Height ◽  
Chemical Analyses ◽  
Nucella Lapillus ◽  
Nw Spain ◽  
Potential Applications ◽  
Penis Length ◽  
The Mean ◽  
Tbt Biomonitoring ◽  
Tbt Pollution

AbstractWe have monitored tributyltin (TBT) pollution in Galicia (NW Spain) for more than a decade by means of assessing gastropod imposex in populations of Nucella lapillus (N ≥ 34) and Tritia reticulata (N ≥ 18) at regular intervals. Several thousand specimens were processed to obtain their shell height (SH), penis length (PL) and vas deferens sequence (VDS); imposex indices (including the VDS index, VDSI) were subsequently calculated. The regional mean SH of both females and males has not changed significantly in either species throughout the study. This also applies to the mean male PL in N. lapillus, but male T. reticulata penises surprisingly enlarged. On the contrary, the regional mean female PL (MFPL) and all imposex indices significantly decreased in both snails. Results confirm previous conclusions based on the chemical analyses of tissues and partial imposex observations. In addition, the close correlations between MFPL and VDSI show some potential applications to TBT biomonitoring.

Diving beetles (Dytiscidae) as predators of mosquito larvae (Culicidae) in field experiments and in laboratory tests of prey preference

2003 ◽  
Vol 93 (3) ◽  
pp. 219-226 ◽  
Author(s):  
E. Lundkvist ◽  
J. Landin ◽  
M. Jackson ◽  
C. Svensson
Keyword(s):  
Body Length ◽  
Negative Correlation ◽  
Laboratory Tests ◽  
Field Experiments ◽  
Mosquito Larvae ◽  
Natural Control ◽  
Large Numbers ◽  
Diving Beetles ◽  
The Mean ◽  
Artificial Ponds

AbstractField experiments were performed in artificial ponds to evaluate how the density of predatory diving beetles (Dytiscidae) would affect the population levels of mosquito larvae (Culicidae). Mosquitoes colonizing the ponds were predominantly species of the genus Culex. In 2000, most of the dytiscids colonizing the ponds were small (Hydroporus spp.), and these predators had no impact on the size of larval mosquito populations, not even in ponds with added dytiscids. In 2001, larger beetles (Ilybius, Rhantus, and Agabus spp.) were more common, and there were significantly fewer mosquito larvae in ponds with the highest numbers of dytiscids. There was a negative correlation between numbers of diving beetles in the ponds and the mean body length of mosquito larvae. In neither year could dytiscid densities be maintained above a certain level owing to emigration. In laboratory tests, there were marked differences between three common dytiscid species in regard to preferences for Daphnia and Culex species as prey: Colymbetes paykulli Erichson chose mosquito larvae more often, whereas both Ilybius ater (De Geer) and I. fuliginosus (Fabricius) preferred Daphnia spp. All of the tested dytiscids consumed large numbers of prey. Since some dytiscid species can efficiently decrease populations of mosquito larvae, they are probably important in the natural control of these dipterans.

scholarly journals The Output of Spermatozoa in Rams II. Relationship to Scrotal Circumference, Testis Weight, and the Number of Spermatozoa in Different Parts of the Urogenital Tract

1972 ◽  
Vol 25 (2) ◽  
pp. 359 ◽  
Author(s):  
BF Lino
Keyword(s):  
Vas Deferens ◽  
Mean Value ◽  
Urogenital Tract ◽  
Regression Coefficients ◽  
Testis Weight ◽  
Scrotal Circumference ◽  
Significance Levels ◽  
The Mean ◽  
Different Parts

Daily spermatozoan output from the urogenital tract (DSOU), scrotal circumference, testis weight, and the numbers of spermatozoa in the epididymis and other parts of the urogenital tract were measured in 10 rams. Testis weight and the numbers of spermatozoa in the head, body, and tail of the epididymis and in the vas deferens and ampulla were found to be bilaterally symmetrical in each ram. The daily spermatozoan output from the urogenital tract was linearly correlated with testis weight (r = o� 83), with epididymal spermatozoan reserves (r = 0'86), with extragonadal spermatozoan reserves (r = 0�90), and with the total number of spermatozoa in the urogenital tract (r = O� 84). The significance levels of the regression coefficients indicated that these parameters would give good estimates of each other. The total number of spermatozoa in the urogenital tract of all rams at slaughter divided by the predicted time taken for spermatozoa to traverse the tract was found to be approximately 6% below the mean value for the daily spermatozoan output of all rams.

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