scholarly journals Recovery of hematocrit and fat deposits varies by cage size in food‐restricted captive red crossbills ( Loxia curvirostra )

Author(s):  
Dawson C. Bradley ◽  
Megan Wurtz ◽  
Jamie M. Cornelius
2021 ◽  
Vol 9 ◽  
Author(s):  
Jamie M. Cornelius ◽  
Thomas P. Hahn ◽  
Ashley R. Robart ◽  
Ben J. Vernasco ◽  
Dorothy L. Zahor ◽  
...  

Physiological preparations for migration generally reflect migratory strategy. Migrant birds fuel long-distance flight primarily with lipids, but carrying excess fuel is costly; thus, the amount of fat deposited prior to departure often reflects the anticipated flight duration or distance between refueling bouts. Seasonal pre-migratory deposition of fat is well documented in regular seasonal migrants, but is less described for more facultative species. We analyze fat deposits of free-living birds across several taxa of facultative migrants in the songbird subfamily Carduelinae, including house finches (Haemorhous mexicanus), American goldfinches (Spinus tristis), pine siskins (Spinus pinus) and four different North American ecotypes of red crossbills (Loxia curvirostra), to evaluate seasonal fat deposition during facultative migratory periods. Our data suggest that the extent of seasonal fat deposits corresponds with migratory tendency in these facultative taxa. Specifically, nomadic red crossbills with a seasonally predictable annual movement demonstrated relatively large seasonal fat deposits coincident with the migratory periods. In contrast, pine siskins, thought to be more variable in timing and initiation of nomadic movements, had smaller peaks in fat deposits during the migratory season, and the partial migrant American goldfinch and the resident house finch showed no peaks coincident with migratory periods. Within the red crossbills, those ecotypes that are closely associated with pine habitats showed larger peaks in fat deposits coincident with autumn migratory periods and had higher wing loading, whereas those ecotypes associated with spruces, Douglas-fir and hemlocks showed larger peaks coincident with spring migratory periods and lower wing loading. We conclude that population averages of fat deposits do reflect facultative migration strategies in these species, as well as the winter thermogenic challenges at the study locations. A difference in seasonal fattening and wing loading among red crossbill ecotypes is consistent with the possibility that they differ in their migratory biology, and we discuss these differences in light of crossbill reproductive schedules and phenologies of different conifer species.


2012 ◽  
Vol 279 (1745) ◽  
pp. 4223-4229 ◽  
Author(s):  
Julie W. Smith ◽  
Stephanie M. Sjoberg ◽  
Matthew C. Mueller ◽  
Craig W. Benkman

How reproductive isolation is related to divergent natural selection is a central question in speciation. Here, we focus on several ecologically specialized taxa or ‘call types’ of red crossbills ( Loxia curvirostra complex), one of the few groups of birds providing much evidence for ecological speciation. Call types differ in bill sizes and feeding capabilities, and also differ in vocalizations, such that contact calls provide information on crossbill phenotype. We found that two call types of red crossbills were more likely to approach playbacks of their own call type than those of heterotypics, and that their propensity to approach heterotypics decreased with increasing divergence in bill size. Although call similarity also decreased with increasing divergence in bill size, comparisons of responses to familiar versus unfamiliar call types indicate that the decrease in the propensity to approach heterotypics with increasing divergence in bill size was a learned response, and not a by-product of calls diverging pleiotropically as bill size diverged. Because crossbills choose mates while in flocks, assortative flocking could lead indirectly to assortative mating as a by-product. These patterns of association therefore provide a mechanism by which increasing divergent selection can lead to increasing reproductive isolation.


Author(s):  
J. Sepulveda-Saavedra ◽  
I. Vander-Klei ◽  
M. Venhuis ◽  
Y. Piñeyro-Lopez

Karwinskia humboldtiana is a poisonous plant that grows in semi desertic areas in north and central México. It produces several substances with different toxic effects. One of them designated T-514 damages severely the lung, kidney and liver, producing in the hepatoeyte large intracellular fat deposits and necrosis. Preliminary observations demonstrated that three is a decrease in the amount of peroxisomes in the hepatocytes of experimentally intoxicated rats and monkeys. To study the effect exerted by the T-514 on peroxisomes, a yeast model was selected, thus, three species: Saccha romices cerevisiae, Ilansenula polymorpha and Candida boidinii were used, because there is information concerning their peroxisome's morphology, enzyme content, biological behaviour under different culture conditions and biogenesis.


Author(s):  
Rachida Rafiq ◽  
Floor Walschot ◽  
Paul Lips ◽  
Hildo Lamb ◽  
Roos Albert de ◽  
...  

2016 ◽  
Vol 52 ◽  
pp. 128-133
Author(s):  
I. V. Khatko ◽  
A. O. Onyshchenko ◽  
V. O. Vovk ◽  
T. M. Konks

The modern state of social-economic processes development demands increasing the level of food safety of the state, especially providing population by the high quality foods of domestic production, specifically by pork. One of criteria for estimating pigs' meatness is determining the fat thickness in different points of a trunk. The informative content of measuring in different parts of a trunk is different and it needs detailed study. The fat thickness is the most common as trait for pigs' meatness in the practice of pig breeding because it has high correlation with meat yield in carcasses. The aim of our research was the comparative study of fat deposition regularities in different parts of a trunk of Large White and Mirgorod pigs in different age periods. For conducting researches 24 pigs of both breeds with average live weight about 40 kg and at age not more 4 months were selected. The fat thickness was measured at live animals using ultrasonic device Draminski in such points: on withers, the level of the 6-7th thoracic vertebra, the level of the 1st-2nd loins vertebra and sacrum. Measuring the fat thickness was carried out at the age of 4, 5, 6, 7 and 8 months. During researches it was carried out the statistical processing of obtained material. Reliability of obtained indexes of productivity was determined. Regularities of formatting fat thickness and fat deposition rate depending on the age were studied. For the results of researches it has been studied and compared economically valuable traits of the most spread domestic pigs of Large White and Mirgorod breeds. By comparative study of growth and development of young pigs of experimental and control groups it has been found that animals of Large White breed differed by lesser fat deposits in all points of measuring. Thus, at 6-months’ age they had lesser thickness of fat in all parts of a trunk. More expressed tendency was at withers and the level of the 6-7th thoracic vertebra, at that in the first case the difference between groups was reliable (p < 0.01). The fat deposition rate in young pigs of both breeds was not the same in different points of measuring along a trunk. Above mentioned tendencies were intensified with the age. Purebred animals of intrabreed type LW-1 at 7-months’ age had reliable less thickness of fat in comparison with the control group: on withers (p < 0.01), at the level of the 6-7th thoracic vertebra, the level of the 1st-2nd loins vertebra (p < 0.05) and on sacrum (p < 0.01). In future, according to economic and scientific expediency, the animals of Mirgorod breed were excluded from the experiment. Concerning Large White breed, the researches were finished when animals were at 8 months’ age. The process of fat deposition in Large White pigs was less intensive in comparison to Mirgorod breed. The highest relative rate of fat thickness increase in both breeds was observed at the level of the 1st-2nd loins vertebra. By statistical processing of the obtained materials it has been found that the difference of average arithmetical indexes (as absolute and relative) between the experimental and control groups during growth and development had distinct tendency to increasing in all points of measuring. The reliability of the difference between the averages in groups with the age of animals increased. A higher reliability of data was obtained at measuring of the front parts of a trunk of pigs at the level of the 6th-7th thoracic vertebra and on withers. The carried out researches at all points of measuring give the reason to confirm that the fat deposits of Large White pigs are less comparing to Mirgorod breed. Conclusions. 1. Carcasses of animals of intrabreed type ULW-1 are comparatively more technologically suitable and economically beneficial for agricultural proceeding industry. 2. Animals of intrabreed type ULW-1 at 7-months’ age had reliable less thickness of fat in comparison with the control group: on withers, at the level of the 6-7th thoracic vertebra, the level of the 1st-2nd loins vertebra and on sacrum. 3. The process of fat deposition in Large White pigs was less intensive in comparison to Mirgorod breed.


2017 ◽  
Vol 68 (7) ◽  
pp. 1438-1441 ◽  
Author(s):  
Sorin Berbece ◽  
Dan Iliescu ◽  
Valeriu Ardeleanu ◽  
Alexandru Nicolau ◽  
Radu Cristian Jecan

Obesity represents a global health problem. According to the latest studies released by the World Health Organisation (WHO), 1.7 billion currently in excess of normal weight individuals, of which approx. 75% are overweight (body mass index - BMI 25 to 30). The common form of excess adipose tissue manifestation in overweight individuals is localized fat deposits with high (abdominal) or low (buttocks and thighs) disposition. Although the overweight can be corrected relatively easy by changing behavioral habits or food, a constant physical exercises program or following a diet food are not accessible to all through the efforts of will, financial and time involved. Several methods have been studied and tested over time to eliminate more or less invasive fat deposits with varying efficacy and adverse effects. Chemical lipolysis using phosphatidylcholine as the basic substance was initially used in hypercholesterolemia and its complications and was rapidly adopted in mesotherapy techniques for the treatment of fat deposits. This study reveals the results obtained using Dermastabilon on a sample of 16 patients, the time allocated to treatment and discomfort being minimal, and rapid and notable results. There were no side effects.


2020 ◽  
Author(s):  
Craig W. Benkman ◽  
Matthew A. Young
Keyword(s):  

Author(s):  
Pei Zhao ◽  
Bundet Boekfa ◽  
Ken-ichi Shimizu ◽  
Masaru Ogura ◽  
Masahiro Ehara

Density functional theory calculations have been applied to study the selectivity caused by the cage size during the selective catalytic reduction of NO by NH3 over the Cu-exchanged zeolites with cha, gme, and aft cages.


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