Incubation

About: Incubation is a research topic. Over the lifetime, 5748 publications have been published within this topic receiving 126541 citations.

Egg mass determines hatchling size, and incubation temperature influences post-hatching growth, of tuatara Sphenodon punctatus

Abstract: The size of reptile hatchlings can be phenotypically plastic in response to incubation temperature, and size is a trait likely to influence fitness – i.e. hatchling size is proposed as an indicator of quality. The parental and incubation temperature effects on the size of one of New Zealand's most biologically significant reptile species, the tuatara Sphenodon punctatus are investigated. Artificial incubation at constant temperatures is used to produce founders for new captive and wild populations of tuatara and to augment existing rare populations. We compare size of hatchling tuatara from artificial and natural incubation treatments. The relationship of hatchling size with incubation temperature and sex is examined, and we investigate whether our results support differential fitness models for the evolution of temperature-dependent sex determination in tuatara. Initial egg mass is the most important factor affecting size of hatchling tuatara and is still an important influence at 10 months of age. Incubation temperature does not greatly influence size of hatchlings, but significantly influences size by 10 months of age. Constant artificial incubation conditions result in larger, but possibly less aggressive, juveniles than those from more variable natural incubation conditions by 10 months of age. Evidence from size patterns of tuatara incubated in natural nests supports differential fitness models for the adaptive significance of temperature-dependent sex determination. Thermal variation has little effect on size of male hatchlings, but female embryos that develop in more stable thermal conditions, in more reliable sites for hatching, are bigger and have longer jaws.

In vitro removal of deoxynivalenol and T-2 toxin by lactic acid bacteria

Abstract: Five strains of lactic acid bacteria were tested for their ability to remove deoxynivalenol (DON) and T-2 toxin from MRS broth. The ability of Lactobacillus plantarum strain 102 (LP102) was the strongest among 5 strains after incubation at 37°C for 72 h. The mode of removal was physical binding, rather than biotransformation. The abilities were not significantly different between when removing single toxin and when removing mixed toxins by viable cells of LP102. DON and T-2 toxin released from LP102 viable cell-toxin complexes were 28.22±1.55 and 35.42±2.02% of total bound toxins respectively after 3 times of wash with posphate buffered saline, respectively, those were 4.59±0.86 and 5.59±1.47% after incubation with simulated gastric fluid (SGF) at 37oC for 4 h, and 6.86±0.81 and 9.04±1.13% after incubation with simulated intestinal fluid (SIF) at 37oC for 4 h, respectively.

How incubation temperature influences the physiology and growth of embryonic lizards.

Abstract: Eggs of two small Australian lizards, Lampropholis guichenoti and Bassiana duperreyi, were incubated to hatching at 25 degrees C and 30 degrees C. Incubation periods were significantly longer at 25 degrees C in both species, and temperature had a greater effect on the incubation period of B. duperreyi (41.0 days at 25 degrees C; 23.1 days at 30 degrees C) than L. guichenoti (40.1 days at 25 degrees C; 27.7 days at 30 degrees C). Patterns of oxygen consumption were similar in both species at both temperatures, being sigmoidal in shape with a fall in the rate of oxygen consumption just prior to hatching. The higher incubation temperature resulted in higher peak and higher prehatch rates of oxygen consumption in both species. Total amount of oxygen consumed during incubation was independent of temperature in B. duperreyi, in which approximately 50 ml oxygen was consumed at both temperatures, but eggs of L. guichenoti incubated at 30 degrees C consumed significantly more (32.6 ml) than eggs incubated at 25 degrees C (28.5 ml). Hatchling mass was unaffected by either incubation temperature or the amount of water absorbed by eggs during incubation in both species. The energetic production cost of hatchling B. duperreyi (3.52 kJ x g(-1)) was independent of incubation temperature, whereas in L. guichenoti the production cost was greater at 30 degrees C (4.00 kJ x g(-1)) than at 25 degrees C (3.47 kJ g(-1)). Snout-vent lengths and mass of hatchlings were unaffected by incubation temperature in both species, but hatchling B. duperreyi incubated at 30 degrees C had longer tails (29.3 mm) than those from eggs incubated at 25 degrees C (26.2 mm). These results indicate that incubation temperature can affect the quality of hatchling lizards in terms of embryonic energy consumption and hatchling morphology.

Prolactin and parenting in the pigeon family

Abstract: The relationship between plasma prolactin and: (1) crop growth; (2) incubation; (3) brooding; and (4) feeding young in Columbiformes is reviewed. There is a good parallel between changes in crop growth and plasma prolactin fluctuations during the breeding cycle. Prolactin does not play a role in the initiation of incubation, though it can maintain the response. Toward the end of breeding, a decline in prolactin precedes the decline in incubation (of infertile eggs) or brooding (of young), while exogenously administered prolactin can prolong the response. There is no evidence of a necessary relationship between prolactin secretion and parental feeding of young, as this behavior can precede and outlast the secretion of the hormone during breeding.

Detection and quantification of Phytophthora capsici in soil.

Abstract: Several assay methods were compared for their efficacy in the detection and quantification of specific propagule types of Phytophthora capsici in soil. Zoospores, oospores, or sporangia and mycelial fragments were added to microwave-treated soil and nontreated field soil at densities from 1 to 1 x 10 4 propagules per g (ppg) of soil. Assay methods included standard soil dilution plating on selective medium without prior sample incubation, as well as dilution plating of soil, saturation water, or a pepper leaf disk bioassay after sample saturation, drainage, incubation for 5 days, and a 24-h resaturation period. Zoospore inoculum was detected at 10 ppg of soil or higher with standard soil dilution plating and the leaf disk bioassay, compared to >100 ppg of soil with dilution plating of soil or saturation water after sample incubation. Sporangial inoculum was detected at 1 ppg of soil with all assays when soil water matric potential was controlled during sample incubation. Oospores were detected at 1 ppg of soil with soil dilution and leaf disk assays after sample incubation. Maximum recovery rates were 10 and 100% of added zoospore and sporangial inoculum, respectively, with standard soil dilution plating (no incubation), and 30% of oospore inoculum with soil dilution plating after sample incubation. A constant soil water matric potential of -10 J/kg during the sample incubation period improved inoculum recovery with all assays, compared to incubation without controlled soil water matric potential. The sample incubation and saturation periods stimulated oospore germination and allowed detection and recovery of oospores added to soil. For most assay methods, recovery of all propagule types was lower in field soil than in microwave-treated soil ; however, the lower limits of detection were comparable in both soils. Although no single assay method was suitable for the accurate detection and quantification of all propagule types of P. capsici, the leaf disk assay provided the best detection of all propagule types but was not sufficiently quantitative to estimate inoculum densities. Soil dilution plating without prior sample incubation was the best assay for the quantification of zoospores and sporangia, whereas soil dilution plating after sample saturation and incubation provided the best recovery of oospores.