Archive for August, 2006
ORNITOLOGIA NEOTROPICAL 9: 209â212, 1998 © The Neotropical Ornithological Society
Salvador Peris & A. Llanes1Department of Animal Biology-Zoology, Faculty of Biology, University of Salamanca, 37071 Salamanca, Spain. 2Institute of Ecology and Systematic. Ministry of Science, Technology and Environment of Cuba.
209 INTRODUCTION Following to Ridgely & Tudor (1989), we considered the Cave Swallow (Hirundo fulva) as a species distinct from the Chesnut-collared Swallow (H. rufocollaris), which has breeding populations in Ecuador and PerĂș. The Cave swallow breeds in Central America, the Caribbean and in the southern U.S. The species is widely distributed in Cuba and the Juventud Isle (fomerly called Isle of Pines), where it breeds on farm-houses, factories, sea cliffs and in natural caves (Bond 1990), wintering in small flocks in the country (Garrido 1988). In spite of its relative abundance, little is known of its breeding biology in the Caribbean. The aim of this study is to provide information on the breeding biology of two Cave Swallow populations in two different habitats of central Cuba. STUDY AREA AND METHODS Observations were made in the caves of Beruvides-SebastiĂĄn, located 1.5 km east of the village of Agramonte (22°40âN, 81°08âW), province of Matanzas (central Cuba). The other colony, also located in the Matanzas province, was situated on a high factory building in San Antonio de Los Baños (23°03âN, 81°31âW). Both localities are situated in a mixed urban-agricultural area. The colonies were monospecific, without association with other swallow species, as has been fund elsewhere (Huels 1985). The caves of Agromonte have numerous escarpments, which the swallows use to attach their nests. The nests of the San Antonio colony are fund on the top of roof beam. In both colonies, a mist-net 9 x 2 m, was set up during the morning at the entrance of the caves and building, from 20 March to 22 December 1993; a total of 215 birds were captured. Most of the birds were weighed, measured, banded with a U.S. Fish & Wildlife Service aluminum ring and released afterwards. The following measurements were taken
GENERAL BIOLOGY following Svensson (1984): wing length (flattened and straightened), tail, tarsus length and bill length (from the nostrils to the tip of the bill). In April, the birds were sexed using as criteria the presence or absence of an incubation patch and the morphology of the cloacal protuberance. Nest measurements included height above the ground, external maximum diameter, internal maximum diameter and depth of the nest Ìs concavity. Eggs were measured (length and width) with a slide caliper to the nearest 0.1mm. Egg weight was obtained by a Pesola balance to the nearest 0.5 g and only in the first three incubation days. Statistitests (Fowler & Cohen 1987). RESULTS AND DISCUSSION Measurements and morphology of the breeding birds. No apparent sexual dimorphism was found in plumage characters. Although males were slightly larger than females, no significant differences (mean ± SD; P > 0.05) were found between the sexes in body mass: male 17.6 g ± 1.2, female: 17.6 g ± 1.4; wing lenght: male 102.1 mm ± 0.2, female: 101.3 mm ± 0.1; tail length: male 41.0 mm ± 0.2, female 41.4 mm ± 0.2; tarsus length (12.7 mm ± 0.0) and culmen length (5.5 mm ± 0.0), nor between the birds from the two study localities. Brood patches were present in all the females captured from late April to early August. This patch is not so well developed in males, being a useful character in sexing swallows (Fig. 1). Cloacal protuberance is only slightly marked in females, but it is well developed in males (Fig. 1), being also a good character for sex discrimination during the breeding season (late April to early August). The eggs size were measured only in one locality (Agromonte): mean length = 20.5 mm ± 0.1 (CV = 5.0), width: 14.5 mm ± 0.1 (CV = 3.2), and fresh weight = 2.1 g ± 0.2 (CV = 1.9). Molting of the inner primaries began in both sexes from early-middle June to middle December, reaching its maximum during September and October, when all the captured birds were moulting (Fig. 2). Comparison between nests in natural caves and factory buildings. Median height of the nests above the ground in natural caves was very similar to those measured in buildings (Table 1). Nests from the human settlements in San Antonio have significantly larger diameters and width than these situated in the caves (Table 1). Depth and height of the nests were similar in both localities, but which a statistiFIG. 1. Percentage of occurrence of cloacal protuberance and brood patch according to seasons, in breeding Cave Swallows from Matanzas (central Cuba). FIG. 2. Percentage of Cave Swallow individuals molting in Matanzas, central Cuba.SHORT COMMUNICATIONS Although height and depth are important parameters in nest-boxes nesting birds in order to increase the number of eggs and nestlings (East & Perrins 1988, Pascual 1994), also the nest width could implicate differences in clutch size. Unfortunately, clutch size in the San Antonio colony was impossible to record and no comparisons with the Agromonte colony (with an average clutch size of two eggs by nest) are possible. The larger structural dimensions of the nests in the factories may be due to their support on beam-buildings with the need of larger and more robust nest-material on these structures without walls. In contrast, the nests on natural depressions are firmly attached to the rocky walls and do not need the support of large material. However, Martin & Hector (1988) observed the use of wool as a lining material in the nest of cave swallows in Texas (US) with potential negative effects on the breeding perfomance of the birds due to lack of proper nestling thermoregulation. In our populations no lining material of human origin was observed, in spite of the nearby high population density in both localities. However, if temperature has an indirect effect on nest-building (Elkins 1983) the differences found in nest Ìs size could indicate the warmer environment of the buildings, and a need for larger nest structure in order to avoid hyperthermia, in comparison with the ACKNOWLEDGMENTS Manuscript was improved by an anonymous reviewer. Partial funding was provided by the Instituto de EcologĂa & SistemĂĄtica, Ministry of Science, Technology & Environment of Cuba and the Universidad de Salamanca of Spain. REFERENCES Bond, J. 1990. Birds of the West Indies. Collins, Hong-Kong. East, M. L., & C. M., Perrins.1988. The effect of nestboxes on breeding populations of birds in broadleaved temperate woodlands. Ibis 130: 393â401. Elkins, N. 1983. Weather and bird behaviour. Poyser, Calton, U.K. Fowler, J., & L. Cohen. 1987. Statistics for ornithologist. BTO Guide 22. Tring, U.K. Garrido, H. H. 1988. La migraciĂłn de las aves en Cuba. Publ. Asoc. Amigos de Doñana no 0. Sevilla. Huels, T. R. 1985. Cave Swallow paired with Cliff Swallows. Condor 87: 441â442. Martin, R. F., & D. Hector.1988. Nest lining with sheep wool. Potential negative effects on cave swallows. Wilson Bull. 100: 294â296. Pascual, J. A. 1993. OcupaciĂłn de distintos modelos de nidal por el Estornino negro (Sturnus unicolor). Doñana Act. Vertebrata 20: 165â178. Ridgely, R. S., & G. Tudor. 1989. The birds of South America. The oscine passerines. Univ. of TABLE 1. Cave Swallow nest measurements (mm) at two study localities in Matanzas Province, Cuba. San Antonio (n = 32) Agramonte (n = 35) t-test Width 154.7 140.2 2.095* Internal diameter 87.0 72.0 4.002** External diameter 113.4 103.0 2.282** Depth 46.4 40.9 1.776 ns Height 72.0 74.7 0.499 ns *P < 0.05; **P < 0.01.GENERAL BIOLOGY Svensson, L. 1975. Identification guide to European passerines. Naturhistoriska Riskmuseet, Stockholm.
August 25th, 2006
kmtrip.net
Known as one of “the biggest and most splendid cave in Asia”, the Swallow Cave Scenic Region is located in the mountains 30 km east of Jianshui, and consists of a dry cave, a water cave and a 30,000-square-meter natural forest, with a total area of 100,000 square meters. Every year between spring and summer, thousands of swallows will fly here from Malaysia, building nests and giving birth to and raising young swallows. Thus it is named “the Swallow Cave”. The local environment is a perfect dwelling for swallows because steep cliffs make it impossible for mice and snakes to come up, and bushes and grassland outside the cave help produce insects that provide abundant food for swifts. The special ecosystem makes a grand scene-”the gathering of thousands of swallows”.
Swallows build their nests with grass and their nutritious saliva. The steamed swallows ‘nest is a delicacy-edible bird’s nest. Every year from August 8 to 10 during the famous “Bird’s Nest Festival”, some local people will climb up the dazzling 50-meter-high cliffs to fetch these nests. During the three days, many people will gather here and watch the dangerous but exciting nest-collecting activity.
Every year on March 21, another special but even more dangerous and exciting activity is the board-hanging ceremony. As a rule, firecrackers are let off to express people’s good wishes to climbers. Then in a merry atmosphere, those brave men slowly and carefully climb up, barehanded. Although it is very dangerous, no one has failed to hang a board onto the top. Nowadays, over 1,000 boards hang on the stalactites over the entrance, some of which have been there for generations.
Inside the Swallow Cave, there is a tourist track of about 3,000 meters. The upper part is a dry cave and the lower part is a water cave. Along the track, there are three main scenic areas, namely, “Exploring Along Dragon Spring”, “Picking up Beauty in Heavenly Streets” and “Wonder Land”. The total tourist area reaches 40,000 square meters. Entering the cave, steeping up the stairs on the left and passing through a narrow cave, one arrives at the “air veranda”, which gives people a dazzling feeling. The scene in the water cave is marvelous as well, which a 50-meter-high and 30-meter-wide entrance. The Lujiang River pours into the cave through the entrance as its underground river. Experts have proved that the water cave has had a history of three million years. Due to the wash of water, stalactites of different shapes have come into being. The dry cave is shaped like a grand hall, big enough to contain 1,000 people. It is a place for rest and for watching local performances. At the exit, three different pieces of the sky can be seen at three different positions. This is another unique scene, which adds luster to the cave.
August 25th, 2006
crystalswiftlets.com
Swiftlet Populated Areas in the Asian Continent
Swiftlets (or Collocalia Fuciphaga) are predominantly found throughout the South East Asian region.
The demand for their nests as a food delicacy has been growing exponentially on global scale powered by the many affluent chinese communities living throughout the world.
The price of 1 kilogramme (about 80 to 100 nests depending on their size and weight) of unprocessed white birds nest obtained from commercial shop-lots that have been converted into swiftlet farming houses can fetch around USD$1,500.00.
Once these unprocessed nests are cleaned, processed, treated and packed, the same kilogramme can cost upwards of USD$4,000.00
The above yellow highlighted areas in Asia are the only places in the world where Swiftlets can be found. In Peninsular Malaysia, commercial farming of swiftlets in old shop-lots and commercial premises are popularly carried out in the states of Kedah, Penang, Perak, Kelantan and Terengganu.
Major Swiftlet Farming Towns in Northern Malaysia
The following are just some of the statistics of swiftlet farming houses in some of the towns in the above states as at middle of June 2005*:
1. Georgetown - 400+ shop houses converted into swiftlet farms
2. Nibong Tebal - 600+ shop houses converted into swiftlet farms
3. Taiping - 400+ shop houses converted into swiftlet farms
4. Setiawan - 800+ shop houses converted into swiftlet farms
5. Parit Buntar - 400+ shop houses converted into swiftlet farms
6. Alor Setar - 300+ shop houses converted into swiftlet farms
7. Kota Bahru - 400+ shop houses converted into swiftlet farms
8. Bukit Mertajam - 300+ shop houses converted into swiftlet farms
(Source: the Malaysian Swiftlet Farmers Association, June 05 Newsletter)
Throughout Malaysia, there is an estimated 10,000+ shop houses and commercial premises that have been converted into swiftlet farms in order to harvest edible birds nest from these swiftlets as at June 2005
Potential Swiftlet Yield per Converted Shop House
As a benchmark measure, every ONE (1) square foot of built-up area can comfortably yield one edible birds nest per 3 month period.
For example, a standard 20 feet by 70 feet 2 storey shop-house will have a built up area of 2800 square feet. This means that such a swiftlet farm can yield 2800 edible birds nest per 3 month period. For the entire calender year, such a farm will comfortably yield RM$672,000.00* worth of unprosessed edible birds nest that should be eagerly bought up by local birds nest traders for processing and export to China, Hong Kong, Japan, South Korea and Taiwan.
* 2800 nests per 3 months = 28 kilos per 3 months
 Therefore, 1 year, the farm will yield 112 kilos (28 * 12/3)
 112 * RM$6,000.00 = RM$672,000.00
The Steps Involved in Processing Edible Birds Nests
Processing birdâs nests is a long, tedious and labour-intensive process, which can be simplified into 4 steps: Â
Step 1: Soak the raw birdâs nests in plain water until they expand, then separate them into individual strands.
Step 2: Remove all the feathers from the edible nest-cement contents with a pair of forceps. This step is repeated until all the feathers are detached from the entire nest-cement.
Step 3: The nest-cement strands are then arranged into a mold.
Step 4: Finally, put the molded strands under the fans to dry.
Nutritional Value of Birds Nests
Edible birdâs nests are actually made up of mostly saliva produced by cave-nesting swiftlets. All swiftlets construct their nests with a glutinous nest-cement produced by a pair of large, lobed salivary glands under their tongue. It is this nest-cement that constitutes the raw material of birdâs nest soup and renders the nests of A. fuciphagus and A. maximus of commercial importance. Â
Edible birdâs nests are glycoprotein with properties of protein as well as of carbohydrate. Its composition resembles that of salivary mucin with a high residue content of 2.5 percent. It contains 10.3 percent nitrogen and 17.4 percent carbohydrate with traces of phosphorus, asernate, sulphur and vitamin B1. The energy value per 100g edible portions is 345 kilocalories. The total protein content is about 85 percent with 0.3 percent of fat. Other minerals present are calcium and iron.Â
Amino acids isolated from birds` nests consist of amide, humin, arginine, cystine, histidine and lysine. The total content of mono amino acids is about 6 percent. Recent studies in Hong Kong suggested that it might even be useful in the treatment of AIDS. Young Asian ladies are putting birdâs nests on their priority list in their budget to gain fair complexion and maintain youthfulness. Expecting mothers are also consuming birdâs nests for a healthy baby with perfect complexion. Bird’s Nests also help to strengthen immune systems and lungs for all age groups.
How to Recognize Fake Birds Nests
1. Swiftlets build edible nests from their saliva, which are formed into strands. These strands can be detached into layers when soaked in plain water. As a result, these strands will be of different lengths and sizes. Faked strands are too perfect to even tell a white lie.
2. Genuine birdâs nests will not melt in water easily when boiled for over 2 hours. Take seaweed or flour or any other stand-in in the history of faked birdâs nests, not only will they melt but evaporate in even less than an hour, .let alone last for 2 hours?
3. Genuine high quality birdâs nests should be able to expand to double its normal size after being soaked and cooked.
4. Genuine birdâs nests contain natural protein that emits a unique aroma of its own after being cooked unlike the typical aroma from normal food essence.
5. Fake red-nests or yellowish-nests have even-shining colour that can be the result of dye addictives. These dye addictives can easily dissolve when the birdâs nests are cooked.
August 24th, 2006
WCAX 3Â -Â 2 hours, 10 minutes ago
They are a chatty bunch.
The chatty barn swallow swoops into our homes this Monday morning.
This is a family that is learning life outside the nest just leaving their stable home inside the barn.
It’s a mud nest that’s often built in the rafters of a barn. The barn swallow is a bird that has a sharply forked tail bluish back, pinkish breast, and a cinnamon throat.
We don’t see as many barn swallows as we used to. Maybe there are fewer barns? Or maybe the habitat has changed elsewhere.
Getting breakfast on the wing, the barn swallow it’s our bird-of-the week.
Anson Tebbetts - Channel 3 News
August 24th, 2006
The Weatherford Democrat - Aug 22 8:42 AM
On their trip south, a short Plum Island layover
By Stephen Tait
THE DAILY NEWS (NEWBURYPORT, Mass.)
PLUM ISLAND, Mass. â The sign leading into the Parker River National Wildlife Refuge tells the story of swarms of swallows stopping here to eat up the plentiful moths, spiders and mosquitoes.
On a simple white marker board with a drawing of a swallow-like bird, it asks visitors to drive slowly through the refuge to avoid hurting or killing swallows. âPlease drive slowly,â it reads, âTree swallows in road.â
In fact, the swallows, tens of thousands of them, arenât just in the road at the refuge: theyâre everywhere.
David Larson, the education coordinator at Massachusetts Audubonâs Joppa Flats, said the swallows â up to four species of them â are stopping on the island as they prepare for their journey south. He said they will fatten up by eating insects and bayberries.
Larson said the birds eat bayberries, which are used to make candles, and turn the wax into much needed fat.
âItâs all about food when youâre migrating and getting enough food to go long distances,â he said. âThatâs what their up to.â
Depending on the time of day or oneâs luck, the island could provide a glimpse of hundreds or even thousands of birds flying overhead, feeding on gnats, mosquitoes and other insects.
âIt is really quite spectacular,â Larson said. âI am sure there are undoubtedly many tens of thousands of swallows there.â
He said the birds have been roosting in the evenings, when they donât hunt for insects to eat, in the north pool area in the brackish water marsh on the refuge.
Sunday afternoon Barbara Roggeveen of Needham was with friends at the Hellcat section of the refuge with binoculars around her neck looking for birds on the island. One bird she had no problem finding, she said, were the tree swallows.
âAs we drove in, they were just all over the place,â she said.
The swallows will use the island as a migrating pit stop for the next several weeks, probably into the first week of September, Larson said.
Graham Taylor, the refuge manager, said observing the birds on the island is an âamazing sight.â
âIt is a truly extraordinary event to see thousands and thousands of these birds swirling around and feeding as they make their way south for the winter,â he said. âIt is a constant stream of birds passing through the area.â
Calvin and Loretta Louks of Salem, N.H., have also been soaking in the migration.
While sitting in their car and peering out over the salt marsh, they recounted the experience with the birds they saw late last week. They said it was mid afternoon Friday, just after lunch, when they saw hundreds of the swallows on the refuge.
âIt was remarkable to see the number of birds coming through,â Calvin Louks said. âThey just kept coming in waves and waves.â
Jennifer McQueen of South Africa was with Roggeveen at the refuge looking at many birds which she cannot find in her home country. She pointed out that this is just the beginning of the season when birds collect food in preparation for migration, which gives other birders the opportunity to see the huge flocks starting their journeys from Plum Island.
âItâs been just the start of the collecting,â she said.
Stephen Tait writes for The Daily News in Newburyport, Mass
August 23rd, 2006
Gloucester Daily Times - Aug 22 9:11 AM
By Stephen Tait
Gloucester Daily Times
PLUM ISLAND - The sign leading into the Parker River National Wildlife Refuge tells the story of swarms of swallows stopping here to eat up the plentiful moths, spiders and mosquitoes.
On a simple white marker board with a drawing of a swallow-like bird, it asks visitors to drive slowly through the refuge to avoid hurting or killing swallows. “Please drive slowly,” it reads, “Tree swallows in road.”
In fact, the swallows, tens of thousands of them, aren’t just in the road at the refuge: they’re everywhere.
David Larson, the education coordinator at Massachusetts Audubon’s Joppa Flats, said the swallows - up to four species of them - are stopping on the island as they prepare for their journey south. He said they will fatten up by eating insects and bayberries.
Larson said the birds eat bayberries, which are used to make candles, and turn the wax into much needed fat.
“It’s all about food when you’re migrating and getting enough food to go long distances,” he said. “That’s what their up to.”
Depending on the time of day or one’s luck, the island could provide a glimpse of hundreds or even thousands of birds flying overhead, feeding on gnats, mosquitoes and other insects.
It is really quite spectacular,” Larson said. “I am sure there are undoubtedly many tens of thousands of swallows there.”
He said the birds have been roosting in the evenings, when they don’t hunt for insects to eat, in the north pool area in the brackish water marsh on the refuge.
Yesterday afternoon Barbara Roggeveen of Needham was with friends at the Hellcat section of the refuge with binoculars around her neck looking for birds on the island. One bird she had no problem finding, she said, were the tree swallows.
“As we drove in, they were just all over the place,” she said.
The swallows willuse the island as a migrating pit stop for the next several weeks, probably into the first week of September, Larson said.
Graham Taylor, the refuge manager, said observing the birds on the island is an “amazing sight.”
“It is a truly extraordinary event to see thousands and thousands of these birds swirling around and feeding as they make their way south for the winter,” he said. “It is a constant stream of birds passing through the area.”
Calvin and Loretta Louks of Salem, N.H., have also been soaking in the migration.
Yesterday afternoon, while sitting in their car and peering out over the salt marsh, they recounted the experience with the birds they saw late last week. They said it was mid afternoon Friday, just after lunch, when they saw hundreds of the swallows on the refuge.
“It was remarkable to see the number of birds coming through,” Calvin Louks said. “They just kept coming in waves and waves.”
Jennifer McQueen of South Africa was with Roggeveen at the refuge yesterday looking at many birds which she cannot find in her home country. She pointed out that this is just the beginning of the season when birds collect food in preparation for migration, which gives other birders the opportunity to see the huge flocks starting their journeys from Plum Island.
“It’s been just the start of the collecting,” she said.
August 23rd, 2006
The Herald - Aug 01 6:11 PM
PAUL ROGERSON
The man who presided over the breakneck expansion of Scotland’s biggest hotel group has left abruptly and without explanation.
Peter Gray, who was chief executive of Kent-based Swallow Hotels, led an acquisition spree which has seen the group take over nearly 40 hotels north of the border since the beginning of last year.
Alan Bowes, executive chairman of London and Edinburgh Swallow Group, insisted the company’s strategy to increase its Scottish portfolio from the current 70 hotels to 100 by 2007 is unaffected by Gray’s departure.
Gray, 46, was tightlipped when contacted at home, saying only: “There is no animosity. I left in very good circumstances. Everyone’s cool.”
In a statement, Bowes said last night: “I can confirm that Peter Gray has decided not to continue his role as Swallow Hotels’ chief executive.
“He has helped us build Swallow Hotels into the fastest-growing hotel chain in the UK and the largest in Scotland.
“After joining us three years ago, when we had just 13 hotels, he has successfully completed this role and has now decided to move on and pursue company paid more than ÂŁ20m for six more Scottish hotels, including well-known golfing and conference venues the Carnoustie Golf Hotel and Resort and the Gleddoch House Hotel and Country Estate at Langbank in Renfrewshire.
Bowes also made the news for different reasons in the spring when Swallow went to court in a legal challenge to Scotland’s smoking ban.
He sought a judicial review of the law, claiming that it breached human rights. He later dropped the challenge.
August 22nd, 2006
WCAX 3Â -Â 27 minutes ago
They are a chatty bunch.
The chatty barn swallow swoops into our homes this Monday morning.
This is a family that is learning life outside the nest just leaving their stable home inside the barn.
It’s a mud nest that’s often built in the rafters of a barn. The barn swallow is a bird that has a sharply forked tail bluish back, pinkish breast, and a cinnamon throat.
We don’t see as many barn swallows as we used to. Maybe there are fewer barns? Or maybe the habitat has changed elsewhere.
Getting breakfast on the wing, the barn swallow it’s our bird-of-the week.
Anson Tebbetts - Channel 3 News
August 22nd, 2006
jbc.org
BY CHI CHE WANG. (Prom the Nelson Morris Institde for Medical Research, Michael Reese Hospital, Chicago.) (Received for publication, September 26, 1921.) Appearance and Origin. The edible birdsâ nests are gelatinous substances produced by certain swifts, the Collacalia, natives of Malaya (1) and Ceylon. The nests, constructed in caves on the seashore, are collected while they are still moist and made into various shapes. The lowest grade is sold in the form of coarse powder. The higher the grade, the whiter the color and fewer the feathers and twigs. Owing to their high price, their use is limited to a delicacy at the feasts of the wealthy and a food for convalescents and the aged. The source from which the birds make the nests has been uncertain. Green (2) gives three suggestions: in the algas found in caves where the swifts make their nests, fish spawn, or a secretion from the swifts them- selves. The algss theory is disproved by the lack of vegetable cells shown by microscopic examinat.ion of the nests. The secretion theory is believed by most of the natives and has the support of Home (3) and Bernstein (4). The latter author found in the birds two large salivary glands which se- creted much viscous mucus. The observation given in this paper shows that the nests consist largely of a mucin-like substance and, therefore, is in accord with the latter hypothesis. by on August 15, www.jbc.org Downloaded from Review of Literature. The literature on the subject is limited. Descriptive statements con- cerning chiefly the occurrence and appearance of the nest may be found in Encyclopedias, China year books, and some semiscientific articles written during the early part of the 19th century. Green (2) and Krukenberg (5) are the first to give a report of a scientific study of the nest. Their work * The work reported in this article was conducted at the Nutrition Laboratory, Department of Home Economics, University of Chicago. It forms part of the thesis submitted in partial fulfillment of the require- ments for the degree of Doctor of Philosophy in the University of Chicago. Proteins of Edible Birdsâ Nests covers the solubilities, the response to protein tests, and some observa- tions on hydrolysis products. Their results prove that the birdsâ nest contains both the carbohydrate and the protein radicle, belonging to the class of mucin-like substances, the glycoproteins. Scope of the Present Work. The present work covers the study of the general properties, the chemical composition, the artificial digestion, the carbohy- drate radicle, and the biological value of the proteins. Compari- son is made with other work on mucin, especially Lothropâs, Mtillerâs, and Leveneâs. The material used for this work was supplied by the Hoo Loong Edible Birdsâ Nest Store, Chicago, which imported it directly from China. It was of the highest grade, having somewhat the appearance of agar-agar, but it was extremely crisp and had tiny feathers interwoven with the mucilaginous material. For quantitative *analysis, the material was ground and sifted. On sifting, most of the feathers cling together and may be removed, but some go through the sieve xo that it is difhcult to. obtain a pure sample. Downloaded fro General Properties. A sample boiled in distilled water for 3 hours and left there for several days, swells like a piece of sponge, but shows no tendency to dissolve. The filtrate responds to neither protein nor carbo- hydrate tests. 5 per cent sodium hydroxide dissolves it on standing 2 hours in the cold. The colorless solution responds to Millonâs, the biuret, xanthoproteic, and Hopkins-Cole tests. The last reaction shows only faintly. It also has a slight reducing power with Fehlingâs reagent. A dilute acid, such as 3 per cent hydrochloric acid, dissolves the birdsâ nests only on heating. The solution acquires a purplish brown color, gives both protein and carbohydrate tests, and has a strong reducing action. So far the properties agree with those reported by Green (2) in every respect except that he found the nest insoluble in dilute sodium hydroxide in the cold. They also agree with the commonly recognized properties of mucin. by on August 15, 2006 ww.jbc.org C. C. Wang Chemical Analysis. 431 Samples between 1.5 to 2 gm. were taken for the determination of moisture and ash. Neumannâs method given in Mathews (6) was used for the estimation of phosphorus, and Denisâs method (7) for that of sulfur. An attempt was made to determine the ether-soluble substance, but the results were too small to be of significance, only 0.3 per cent. The estimation of total nitrogen by the Kjeldahl-Gunning method was made on samples treated in three different ways: (1) original birdsâ nest, (2) ground birdsâ nest with feathers partially removed, and (3) a sample hydro- lyzed for 132 hours in 20 per cent hydrochloric acid. Results are given in Table I. The total ash, 2.51, is almost seven times as high as that of submaxillary mucin, 0.37 per cent,â reported by Lothrop (8). This high percentage of ash shows that the birdsâ nest is not a pure mucin, but more probably dried saliva. Of the total ash 29.48 per cent is insoluble in water, but none insoluble in acid. Hence no sandy material is present. The sulfur content, 1.10 per cent, is in agreement with the figures given by Muller (9) for salivary mucin, 1.40 per cent, but it is higher than that reported by Lothrop (8), 0.55 per cent. The 006 432 Proteins of Edible Birdsâ Nests discrepancy may be due to the different methods used or in case of birdsâ nests, the presence of feathers. The phosphorus, 0.035 per cent, is too small to be of any significance. The different values for nitrogen found in birdsâ nests treated in three different ways may be explained by the variation in the feathers present. The original sample containing the most feathers, had the lowest figure, 8.78 per cent, while that hydrolyzed with the least feathers, the highest or 10.29 per cent. The ground and sifted sample gave 9.15 per cent. Some feathers were re- moved during grinding and sifting, but more of them separated out by clinging to the walls of the vessel on hydrolysis. They could then be easily removed. The percentage of nitrogen of the hydrolyzed material, 10.29, agrees with the value given by Muller (9) for salivary mucin, 10.70 for total nitrogen but it is lower than that reported by Lothrop (8), 12.49 per cent. DowArtijicial Digestion. Artificial digestion experiments carried out in comparison with hard boiled egg white showed that the birdsâ nests were digested by both pepsin hydrochloric acid and trypsin though not so quickly as the egg. The speed of digestion was determined by Sorensenâs titration (6). Comparison was made of the increase during 24 hours in the volume of 0.1 N sodium hydroxide for titrating 25 cc. of the peptic digest. Results were expressed in cc. per gm. of nitrogen in the material acted upon. For the birdsâ nests in a typical experiment this value was 9:60 cc. and for the egg white 15.47 cc. Similarly, the increase of 0.1 N hydrochloric acid to titrate the tryptic digest was 19.02 cc. for the birdsâ nests and 38.75 cc. for the egg white. The percentage of carbohydrate in the hydrolyzed birdsâ nests could not be found with accuracy. Efforts using Benedictâs (10) Method 2 failed to give concordant results. The material was prepared in the following manner: 1 gm. of the ground and sifted nests was dissolved in a small amount of concentrated hydrochloric acid by standing over night. It was then diluted with distilled water to make a 5 per cent acid solution and boiled with a reflux condenser for 13 hours. The hydrolyzed mixture was treated with phosphotungstic acid, filtered, and the fltrate was made up to a definite volume. by on August 15, 2006 www.jbc.org ed from
August 16th, 2006
mirabilis.ca
From the Globe and Mail, Soup good, bad for you.
Bird’s nest soup — maybe that should be bird spit soup — seems to be both unexpectedly healthy and potentially harmful for those who relish its exotic taste.
A chemical analysis by Massimo Marcone of the University of Guelph of several edible nests made by the swiftlet, a small swallow native to East Asia, turned up a protein similar to that found in eggs. The protein is in the nest because the swiftlets weave a new home yearly, not out of sticks or straw but their own saliva.
Marcone argues that the existence of an egg-like protein would explain the mysterious occurrence of a severe allergy attack among some who dine on bird’s nest soup. Indeed, surveys in Singapore have found that the soup is the leading food allergy there.
However, the positive news for the non-allergic is that the same egg protein has been shown to have antibiotic properties. This would account for the legendary health properties of bird’s nest soup, if not quite medicinally justify its price of upwards of $10,000 a kilogram.
August 16th, 2006
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