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G.j. Coman - One of the best experts on this subject based on the ideXlab platform.
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Reproductive Performance of reciprocally crossed wild caught and tank reared penaeus monodon broodstock
Aquaculture, 2006Co-Authors: G.j. Coman, Peter J. Crocos, Stuart J Arnold, Silvio Peixoto, Frank E Coman, Nigel P PrestonAbstract:Abstract The Reproductive Performance of reciprocally crossed wild-caught (W) and domesticated lines (L1 and L2) of Penaeus monodon broodstock was assessed over two moult periods under standardised conditions. Significant variations in the Reproductive Performance of the broodstock from the three sources (W, L1 and L2) were found. Reproductive Performance was more dependent on the source of the female broodstock than the male broodstock. W females matured and spawned more rapidly after ablation and more often than L1 and L2 females. The percentage of W females spawning (86.8%) was significantly greater than that for both L1 (38.9%) and L2 females (23.7%). W females had significantly more spawnings (1.99 spawnings female − 1 ) than the L1 (0. 62 spawnings female − 1 ) and L2 females (0.37 spawnings female − 1 ), and spawned within a shorter period after ablation (9.2 days compared with 15.3 days for the L1 and 18.7 days for the L2 females). There was no difference in the numbers of eggs per spawning, percentage of spawnings that hatched, hatch rates and protozoeal metamorphosis rates produced from the W and the L1 tank-reared females. However, the L2 females had significantly lower numbers of eggs per spawning, percentage of spawnings that hatched and protozoeal metamorphosis rates per spawning than the W and L1 females. The lower Performance of the L2 stocks, compared with the L1 stocks, demonstrates the variability in Reproductive Performance that can exist between different domesticated stocks. Our results suggest that the largest improvements in the Reproductive output of these tank-reared P. monodon stocks will likely be found through improvements in the quality of the female broodstock.
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Seasonal and age variability in the Reproductive Performance of Penaeus semisulcatus broodstock: optimising broodstock selection
Aquaculture, 1997Co-Authors: Peter J. Crocos, G.j. ComanAbstract:Abstract The knowledge of the inherent Reproductive patterns of wild prawn (shrimp) populations is essential in predicting the expected Performance of hatchery broodstock. In response to problems of variable hatchery Performance of penaeid broodstock at some times of the year, the inherent seasonal variability and the effects of broodstock age on Reproductive Performance of Penaeus semisulcatus were examined. The investigation of these effects, using a penaeid for which the detailed Reproductive ecology was well known, provided a proxy from which to describe the general case likely applicable to other farmed species. During the three-year study, assessments were made for broodstock of known but increasing age collected from the wild overall seasons (at 2-monthly intervals), and from the two distinct age-cohorts present in the same season. The Reproductive Performance of the broodstock was assessed at each stage of the maturation and spawning process. Measures of maturation rate, spawning rate, fecundity, hatch rate, larval survival rate, and larval production rate were obtained. Inherent temporal patterns in the measures of Reproductive Performance were found for the main annual cohort of the wild stock. The rates of spawning, egg production, nauplii production and protozoeae production were lowest in autumn when females were 6 months old, increased through to a spring peak (at 12 months old), and then declined by early summer by which time females were 14 months old. Broodstock survival, egg hatching and metamorphosis of nauplii to protozoeae were unaffected by time of year. Trials with two age-cohorts present in the same season enabled us to separate the effects of age and season. Twelve-month-old broodstock outperformed 6-month-old broodstock, regardless of season. Age was the best predictor of Reproductive Performance. An optimal age of 12 months for best Reproductive Performance was identified. This information can be used to select broodstock for hatchery production. The findings may be applicable to other species of farmed penaeids.
Nigel P Preston - One of the best experts on this subject based on the ideXlab platform.
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Reproductive Performance of reciprocally crossed wild caught and tank reared penaeus monodon broodstock
Aquaculture, 2006Co-Authors: G.j. Coman, Peter J. Crocos, Stuart J Arnold, Silvio Peixoto, Frank E Coman, Nigel P PrestonAbstract:Abstract The Reproductive Performance of reciprocally crossed wild-caught (W) and domesticated lines (L1 and L2) of Penaeus monodon broodstock was assessed over two moult periods under standardised conditions. Significant variations in the Reproductive Performance of the broodstock from the three sources (W, L1 and L2) were found. Reproductive Performance was more dependent on the source of the female broodstock than the male broodstock. W females matured and spawned more rapidly after ablation and more often than L1 and L2 females. The percentage of W females spawning (86.8%) was significantly greater than that for both L1 (38.9%) and L2 females (23.7%). W females had significantly more spawnings (1.99 spawnings female − 1 ) than the L1 (0. 62 spawnings female − 1 ) and L2 females (0.37 spawnings female − 1 ), and spawned within a shorter period after ablation (9.2 days compared with 15.3 days for the L1 and 18.7 days for the L2 females). There was no difference in the numbers of eggs per spawning, percentage of spawnings that hatched, hatch rates and protozoeal metamorphosis rates produced from the W and the L1 tank-reared females. However, the L2 females had significantly lower numbers of eggs per spawning, percentage of spawnings that hatched and protozoeal metamorphosis rates per spawning than the W and L1 females. The lower Performance of the L2 stocks, compared with the L1 stocks, demonstrates the variability in Reproductive Performance that can exist between different domesticated stocks. Our results suggest that the largest improvements in the Reproductive output of these tank-reared P. monodon stocks will likely be found through improvements in the quality of the female broodstock.
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growth survival and Reproductive Performance of domesticated australian stocks of the giant tiger prawn penaeus monodon reared in tanks and raceways
Journal of The World Aquaculture Society, 2005Co-Authors: Greg Coman, Stuart J Arnold, Nigel P Preston, Peter I Crocos, Sandy I Keys, Brian MurphyAbstract:The growth, survival and Reproductive Performance of domesticated Australian stocks of the giant tiger shrimp Penaeus monodon were evaluated in trials conducted in 1997 and 2003. The 1997 trials assessed the Performance of first generation progeny of wild broodstock from the northeast coast of Australia and fourth generation progeny of pond-reared broodstock, which also originated from northeast coast wild stocks. In these trials, growth and survival of the shrimp were assessed when reared for 17 mo in tanks. Reproductive Performance of the shrimp was assessed at 14.5 mo and 17 mo. The 2003 trials assessed the Performance of first generation progeny of wild broodstock from the Gulf of Carpentaria (north coast of Australia). In these trials, growth and survival of shrimp were assessed when reared for 14 mo in tanks and raceways. Reproductive Performance of the shrimp was assessed at 11 mo, 12 mo, and 15 mo. Growth and Reproductive Performance of the stocks varied between trials, families, ages and rearing systems. The most pronounced differences in growth and Reproductive Performance were between the 1997 and 2003 trials. At 11 mo of age, the average wet weight of the shrimp in the 2003 trials (females 117.1 ± 5.8 g; males 87.9 ± 7.6 g) was 200% greater than the average wet weight of shrimp in the 1997 trials (females 55.2 ± 6.8 g; males 41.2 ± 3.4 g). The Reproductive Performance of the shrimp was also higher in the 2003 trials in terms of the percentage of spawnings hatching (52.0% in 1997; 77.1% in 2003) and mean hatch rate (21.5% in 1997; 31.6% in 2003). Differences in the growth and Reproductive Performance of the tank-reared stocks between years were indicative of significant improvements in the rearing environment, diet and husbandry techniques. Variation in the Reproductive Performance between families was consistent across rearing environments and at different ages and suggests the potential to improve Reproductive Performance through genetic selection. Notably, this study identified hatch rates of nauplii from the spawned eggs as a key area for future improvement of domesticated stocks reared in tanks and raceways. Future efforts to improve the growth and Reproductive Performance of domesticated P. monodon could benefit from integrating incremental improvements to husbandry with genetic selection.
Jane M Reid - One of the best experts on this subject based on the ideXlab platform.
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Reproductive Performance of resident and migrant males females and pairs in a partially migratory bird
Journal of Animal Ecology, 2017Co-Authors: Hannah Grist, Francis Daunt, Sarah Wanless, Sarah J Burthe, Mark Newell, M P Harris, Jane M ReidAbstract:Summary 1.Quantifying among-individual variation in life-history strategies, and associated variation in Reproductive Performance and resulting demographic structure, is key to understanding and predicting population dynamics and life-history evolution. Partial migration, where populations comprise a mixture of resident and seasonally-migrant individuals, constitutes a dimension of life-history variation that could be associated with substantial variation in Reproductive Performance. However, such variation has rarely been quantified due to the challenge of measuring reproduction and migration across a sufficient number of seasonally-mobile males and females. 2.We used intensive winter (non-breeding season) resightings of colour-ringed adult European shags (Phalacrocorax aristotelis) from a known breeding colony to identify resident and migrant individuals. We tested whether two aspects of annual Reproductive Performance, brood hatch date and breeding success, differed between resident and migrant males, females and breeding pairs observed across three consecutive winters and breeding seasons. 3.The sex ratios of observed resident and migrant shags did not significantly differ from each other or from 1:1, suggesting that both sexes are partially migratory and that migration was not sex-biased across surveyed areas. 4.Individual resident males and females hatched their broods 6 days earlier and fledged 0.2 more chicks per year than migrant males and females on average. Resident individuals of both sexes therefore had higher breeding success than migrants. 5.Hatch date and breeding success also varied with a pair's joint migratory strategy such that resident-resident pairs hatched their broods 12 days earlier than migrant-migrant pairs, and fledged 0.7 more chicks per year on average. However, there was no evidence of assortative pairing with respect to migratory strategy: observed frequencies of migrant-migrant and resident-resident pairs did not differ from those expected given random pairing. 6.These data demonstrate substantial variation in two key aspects of Reproductive Performance associated with the migratory strategies of males, females and breeding pairs within a partially migratory population. These patterns could reflect direct and/or indirect mechanisms, but imply that individual variation in migratory strategy, and variation in pairing among residents and migrants, could influence selection on migration and drive complex population and evolutionary dynamics. This article is protected by copyright. All rights reserved.
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age specific Reproductive Performance in red billed choughs pyrrhocorax pyrrhocorax patterns and processes in a natural population
Journal of Animal Ecology, 2003Co-Authors: Jane M Reid, E M Bignal, S Bignal, D I Mccracken, Pat MonaghanAbstract:Summary 1. Using data from a 20-year study of individually marked red-billed choughs, we examine how Reproductive Performance varies with age in male and female breeders, and investigate whether population-level trends result from changes in individual Performance and/or the phenotypic composition of the breeding population. 2. Across the population, mean clutch size, the probability of breeding successfully and the number of offspring fledged during successful attempts increased and then declined with female age. Male age did not explain a significant proportion of the residual variation. 3. All three measures of Reproductive Performance improved and then declined with age within individual females. 4. Females that died young laid relatively small clutches and fledged few offspring before death. Thus mean Performance improved across young age classes partly because some poor breeders were absent from older age classes. 5. Females that ultimately reached the greatest ages had laid small clutches and fledged few offspring during their first few breeding attempts. Females that were more productive when they were young had relatively shorter lives. These data indicate a trade-off between early reproduction and future survival in choughs, and suggest that individuals that reach old age are phenotypically distinct from an early stage in their breeding lives. 6. We emphasize that age-specific changes in mean Reproductive Performance observed across wild populations are due to a complex interplay between improvement and senescence at the individual level, as well as changes in the phenotypic composition of the breeding population.
Peter J. Crocos - One of the best experts on this subject based on the ideXlab platform.
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Reproductive Performance of reciprocally crossed wild caught and tank reared penaeus monodon broodstock
Aquaculture, 2006Co-Authors: G.j. Coman, Peter J. Crocos, Stuart J Arnold, Silvio Peixoto, Frank E Coman, Nigel P PrestonAbstract:Abstract The Reproductive Performance of reciprocally crossed wild-caught (W) and domesticated lines (L1 and L2) of Penaeus monodon broodstock was assessed over two moult periods under standardised conditions. Significant variations in the Reproductive Performance of the broodstock from the three sources (W, L1 and L2) were found. Reproductive Performance was more dependent on the source of the female broodstock than the male broodstock. W females matured and spawned more rapidly after ablation and more often than L1 and L2 females. The percentage of W females spawning (86.8%) was significantly greater than that for both L1 (38.9%) and L2 females (23.7%). W females had significantly more spawnings (1.99 spawnings female − 1 ) than the L1 (0. 62 spawnings female − 1 ) and L2 females (0.37 spawnings female − 1 ), and spawned within a shorter period after ablation (9.2 days compared with 15.3 days for the L1 and 18.7 days for the L2 females). There was no difference in the numbers of eggs per spawning, percentage of spawnings that hatched, hatch rates and protozoeal metamorphosis rates produced from the W and the L1 tank-reared females. However, the L2 females had significantly lower numbers of eggs per spawning, percentage of spawnings that hatched and protozoeal metamorphosis rates per spawning than the W and L1 females. The lower Performance of the L2 stocks, compared with the L1 stocks, demonstrates the variability in Reproductive Performance that can exist between different domesticated stocks. Our results suggest that the largest improvements in the Reproductive output of these tank-reared P. monodon stocks will likely be found through improvements in the quality of the female broodstock.
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Seasonal and age variability in the Reproductive Performance of Penaeus semisulcatus broodstock: optimising broodstock selection
Aquaculture, 1997Co-Authors: Peter J. Crocos, G.j. ComanAbstract:Abstract The knowledge of the inherent Reproductive patterns of wild prawn (shrimp) populations is essential in predicting the expected Performance of hatchery broodstock. In response to problems of variable hatchery Performance of penaeid broodstock at some times of the year, the inherent seasonal variability and the effects of broodstock age on Reproductive Performance of Penaeus semisulcatus were examined. The investigation of these effects, using a penaeid for which the detailed Reproductive ecology was well known, provided a proxy from which to describe the general case likely applicable to other farmed species. During the three-year study, assessments were made for broodstock of known but increasing age collected from the wild overall seasons (at 2-monthly intervals), and from the two distinct age-cohorts present in the same season. The Reproductive Performance of the broodstock was assessed at each stage of the maturation and spawning process. Measures of maturation rate, spawning rate, fecundity, hatch rate, larval survival rate, and larval production rate were obtained. Inherent temporal patterns in the measures of Reproductive Performance were found for the main annual cohort of the wild stock. The rates of spawning, egg production, nauplii production and protozoeae production were lowest in autumn when females were 6 months old, increased through to a spring peak (at 12 months old), and then declined by early summer by which time females were 14 months old. Broodstock survival, egg hatching and metamorphosis of nauplii to protozoeae were unaffected by time of year. Trials with two age-cohorts present in the same season enabled us to separate the effects of age and season. Twelve-month-old broodstock outperformed 6-month-old broodstock, regardless of season. Age was the best predictor of Reproductive Performance. An optimal age of 12 months for best Reproductive Performance was identified. This information can be used to select broodstock for hatchery production. The findings may be applicable to other species of farmed penaeids.
Michael P Lombardo - One of the best experts on this subject based on the ideXlab platform.
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effect of feathers as nest insulation on incubation behavior and Reproductive Performance of tree swallows tachycineta bicolor
The Auk, 1995Co-Authors: Michael P Lombardo, Ruth M Bosman, Christine A Faro, Stephen G Houtteman, Timothy S KluiszaAbstract:-Many species of birds line their nests with feathers, presumably because of the insulative qualities of feathers and because feathers may act as a barrier between nest parasites and nestlings. In 1993, we experimentally examined the role of feathers as nest insulation on the incubation behavior, nestling growth, and Reproductive Performance of Tree Swallows (Tachycineta bicolor) nesting in boxes in western Michigan. There were no significant differences between the incubation rhythms of females with experimental nests (i.e. no feathers) and females with control nests (i.e. with feathers). Nestlings that were reared in control nests had significantly longer right tarsi and right wing chords; their masses were significantly greater than nestlings reared in experimental nests. In addition, nested analyses of variance indicated that both female age class (i.e. second year, after second year, or after hatching year) and the brood within which a nestling was reared had significant effects on nestling growth until nestling day 12. Whether an individual nestling was infected with ectoparasites was independent of whether it was reared in an experimental or control nest. Nest insulation affected Reproductive Performance: females with experimental nests had significantly longer incubation periods and produced significantly fewer fledglings than did females with control nests. These results suggest that nest insulation may be an important factor influencing incubation behavior, nestling growth, and Reproductive Performance of Tree Swallows in western Michigan. Received 21 November 1994, accepted 21 June 1995. NESTS ARE an important component of parental effort in birds. Nests provide safety from predators, and a container and microenvironment for incubating parents, developing eggs, and nestlings (Collias and Collias 1984). Nest building is influenced by "instinct" and learning: the nests of experienced birds often are superior to those built by novices (Collias and Collias 1984). Determining the consequences of individual differences in nest architecture on Reproductive Performance are important to a complete understanding of the factors affecting the evolution of parental effort in birds. Tree Swallows (Tachycineta bicolor) build nests made of a mat of dry grasses with a nest cup lined with feathers. Females do most of the nest building (Kuerzi 1941, Sheppard 1977), but males add many of the feathers that line the cup (Sheppard 1977, Cohen 1985). The nests of second-year females are less well feathered than nests built by after-second-year females (Lombardo 1994). Differences in nest feathering may influence the age-related differences in Reproductive Performance that have been observed in Tree Swallows (DeSteven 1978, 1980, Stutchbury and Robertson 1988) because of the effects of feathers on the thermoenergetics of incubation, brooding, and nestling growth. Winkler (1993) experimentally examined the effect of feathers as nest insulation on Reproductive Performance in Tree Swallows nesting in boxes near Ithaca, New York, and found that feathers as nest lining had no effect on fledging success, but nestlings reared in control nests (i.e. with feathers) were larger on the twelfth nestling day, fledged earlier, and had fewer ectoparasites than those reared in experimental nests (i.e. without feathers). He did not examine whether there were female age-related differences in Reproductive Performance that were influenced by feathers as nest insulation. Lombardo (1994) did a correlational study of nest architecture, female age, and Reproductive Performance of Tree Swallows nesting in southeastern Michigan and found no relationship between the amount of nest feathering and the number or proportion of hatchlings and fledglings produced. However, well-insulated nests were advantageous early in the season when ambient temperatures were low and eggs and nestlings needed to be kept warm, but disadvantageous late in the season when ambient
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nest architecture and Reproductive Performance in tree swallows tachycineta bicolor
The Auk, 1994Co-Authors: Michael P LombardoAbstract:ABSTMACT.-Nests are an important component of parental effort in birds. From 1988 to 1990, I compared the architecture of nests built by subadult and adult female Tree Swallows (Tachycineta bicolor) in boxes in southeastern Michigan in order to determine if there were age-related differences in nest architecture and if these differences were associated with agerelated differences in Reproductive Performance. Nests built by Tree Swallows were composed of a mat of dry grasses and a nest cup lined with feathers. On average, nest material filled approximately 30% of a nest box. I observed few age-related differences in nest architecture. However, nests built by subadult females were significantly less well feathered than nests built by adult females, but feather score was not correlated with the production of nestlings or fledglings. There were age-related and within-season variations in Reproductive Performance associated with variations in nest architecture, especially later in the season. Among subadult females that bred later in the season (i.e. after the population median date of clutch initiation), those females that built larger nests (as indicated by total nest volume, depth of material beneath the nest cup, and percentage of nest box filled with material) hatched more eggs per clutch. In 1990, subadult females that bred later in the season and built larger nests (as indicated by depth of material beneath nest cup and percentage of nest box filled with material) produced significantly more hatchlings but significantly fewer fledglings. Among adult females that bred later in the season, those females that built nests that filled a larger percentage of the nest box hatched fewer eggs. Adult females with nests having larger cups produced significantly more fledglings, but those with cups crowded with nestlings (as indicated by a cup index [total egg volume/nest cup volume]) produced significantly fewer fledglings. In 1990, adult females that bred later in the season and built larger nests (as indicated by depth of nest material, total nest volume, percentage of nest box filled with material) and had more-crowded nest cups produced fewer hatchlings and fledged a significantly smaller proportion of hatchlings. These results suggest that nestling hyperthermia in well-insulated nests may affect the Reproductive Performance of Tree Swallows that breed late in the season. Received 11 January 1993, accepted 1 July 1993.
