Diet composition and quality for Calanus finmarchicus egg production and hatching success off south-west Iceland

Moult increments, annual moult frequency and hence annual growth were determined from suture-tagged edible crabs (Cancer pagurusL.) released and recaptured off Devon, Cornwall, and Dorset.The average moult increments of males and females at a premoult carapace width of 100 mm were similar; at larger sizes the average moult increment of females was considerably less than that of males. Annual moult frequency ofC. pagurusin south-west England decreased with increase in size, females more so than males.As a result of the smaller moult increments and lower moult frequency of females, their annual growth is considerably less than that of males. This appears to be the result of three aspects of sex and reproduction: (1) reduction in moult increments, probably as a result of competition for nutritive resources between egg production and body growth; (2) the interruption of the moulting cycle by successive annual spawnings from a single impregnation at the previous moult; and (3) accentuation of the larger increments in weight at moulting of male crabs due to the allometric growth of their chelae. A consequence of the higher growth rate of males is the presence of very large male crabs – a distinctive feature of the population structure of the stock off south-west England.The growth of C.pagurusin south-west England was compared with published data for stocks off the east and north-east coast. Moult increments were similar for both areas, but there were considerable differences in the moult frequencies. In the south-west, males moult more frequently than females; the opposite is the case for the east and north-east crab stocks. A valid reason for this difference has not yet been established.

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Assessing the response of hen weight, body composition, feather score, egg quality, and level of excreta nitrogen content to digestible balanced protein intake of laying hens

Canadian Journal of Animal Science ◽

10.1139/cjas-2017-0134 ◽

2018 ◽

Vol 98 (4) ◽

pp. 619-630 ◽

Cited By ~ 2

Author(s):

D. Kumar ◽

C. Raginski ◽

K. Schwean-Lardner ◽

H.L. Classen

Keyword(s):

Egg Production ◽

Diet Composition ◽

Laying Hens ◽

Egg Quality ◽

N Content ◽

Shell Quality ◽

Randomized Design ◽

Completely Randomized Design ◽

Egg Shell ◽

Level Of Significance

Ideally balanced dietary protein is critical for laying hen egg production and feed efficiency, but also affects other important characteristics. This research was designed to study the nonegg production and feed intake response of Lohmann-LSL Lite hens to 550, 625, 700, 775, and 850 mg d−1 of amino acid balanced digestible lysine (Dlys) from 27 to 66 wk of age. Data collection included hen weight (HW), feather scoring, tissue weights, egg specific gravity, egg component weights, and excreta nitrogen (N) content. The experiment was a completely randomized design and level of significance was fixed at P ≤ 0.05. Hen weight (quadratic, Q), pectoralis muscle (absolute, % – Q), and abdominal fat (absolute – linear, L; % – Q) increased with increasing Dlys intake. Although gastrointestinal segment weights and lengths were affected by Dlys intake, interpretation of results was confounded by other aspects of diet composition. Hen feather score (L) and excreta N content (Q) increased, and egg shell quality (L) decreased with increasing Dlys intake. Absolute egg component weights increased with Dlys intake, but effects on proportional weights were Q and relatively minor. In conclusion, balanced Dlys intake affected a variety of practical nonproduction characteristics in laying hens.

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Do Diploid and Haploid Solitary Cells of Phaeocystis globosa Support the Same Copepod Grazing, Survival, Egg Production, and Hatching Success?

Journal of Coastal Research ◽

10.2112/jcoastres-d-20-00052.1 ◽

2020 ◽

Vol 37 (1) ◽

Author(s):

Jie Li ◽

Jiachang Lu ◽

Jiale Wang ◽

Yinghui Wang ◽

Junxiang Lai ◽

...

Keyword(s):

Egg Production ◽

Hatching Success ◽

Phaeocystis Globosa ◽

Copepod Grazing

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Effects of Experience and Body Weight on Incubation Behavior of Canada Geese

The Auk ◽

10.1093/auk/100.3.670 ◽

1983 ◽

Vol 100 (3) ◽

pp. 670-679 ◽

Cited By ~ 81

Author(s):

Thomas W. Aldrich ◽

Dennis G. Raveling

Keyword(s):

Body Weight ◽

Egg Production ◽

Hatching Success ◽

Important Variable ◽

Canada Geese ◽

Critical Weight ◽

Incubation Behavior ◽

Risk Of Predation ◽

First Time ◽

Foraging Time

Abstract During 1979 and 1980, we studied the incubation behavior and body-weight dynamics of captive Canada Geese (Branta canadensis moffitti) with known breeding histories. Females were attentive to their nests for 97.5% of the incubation period and lost 27% of their initial body weight. Heavier females were more attentive to their nests and lost more weight during incubation than did lighter females. Variation in body weight among females was greatest at the onset of incubation and least at hatch, which suggests that females invested maximum reserves in incubation. Recess frequency and duration increased throughout incubation, resulting in more foraging time for the female. Once a lower critical weight of about 3,200 g was reached, the amount of recess time taken increased dramatically, probably because lipid reserves were depleted. Females nesting for the first time began incubation at a lighter body weight and were less attentive than experienced females. All inexperienced females were either 4 or 5 yr old, but their egg production (4 eggs) was that of 2- or 3-yr-old wild females. This indicated that experience rather than age was the important variable affecting acquisition of reserves. Inattentiveness to a nest by a female prolongs the duration of incubation and exposes the nest to a greater risk of predation. The inability of inexperienced females to gain enough reserves to provide for both maximum clutch size and attentiveness during incubation may be a major explanation for the lower hatching success of geese nesting for the first time.

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Egg production and hatching success in North Adriatic Sea populations of the copepod acartia clausi

Chemistry and Ecology ◽

10.1080/02757540212683 ◽

2002 ◽

Vol 18 (1-2) ◽

pp. 117-125 ◽

Cited By ~ 1

Author(s):

Antonio Miralto ◽

Adrianna Ianora ◽

Isabella Buttino ◽

Giovanna Romano ◽

Mario Di Pinto

Keyword(s):

Egg Production ◽

Hatching Success ◽

Adriatic Sea ◽

Acartia Clausi ◽

North Adriatic Sea

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Polyandry increases reproductive performance but does not decrease survival in female Brontispa longissima

Bulletin of Entomological Research ◽

10.1017/s0007485316000730 ◽

2016 ◽

Vol 107 (2) ◽

pp. 165-173 ◽

Cited By ~ 2

Author(s):

K. Kawazu ◽

W. Sugeno ◽

A. Mochizuki ◽

S. Nakamura

Keyword(s):

Reproductive Performance ◽

Egg Production ◽

Hatching Success ◽

Multiple Mating ◽

Preoviposition Period ◽

Extreme Polyandry ◽

Single Mating ◽

Female Longevity ◽

Experimental Treatments ◽

Direct And Indirect Benefits

AbstractThe costs and benefits of polyandry are still not well understood. We studied the effects of multiple mating on the reproductive performance of female Brontispa longissima (Coleoptera: Chrysomelidae), one of the most serious pests of the coconut palm, by using three experimental treatments: (1) singly-mated females (single treatment); (2) females that mated 10 times with the same male (repetition treatment); and (3) females that mated once with each of 10 different males (polyandry treatment). Both multiple mating treatments resulted in significantly greater total egg production and the proportion of eggs that successfully hatched (hatching success) than with the single mating treatment. Furthermore, the polyandry treatment resulted in greater total egg production and hatching success than with the repetition treatment. Thus, mate diversity may affect the direct and indirect benefits of multiple mating. Female longevity, the length of the preoviposition period, the length of the period from emergence to termination of oviposition, and the length of the ovipositing period did not differ among treatments. The pronounced fecundity and fertility benefits that females gain from multiple mating, coupled with a lack of longevity costs, apparently explain the extreme polyandry in B. longissima.

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