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1.
David H. Baker 《Amino acids》2009,37(1):29-41
The ideal protein concept has allowed progress in defining requirements as well as the limiting order of amino acids in corn,
soybean meal, and a corn–soybean meal mixture for growth of young chicks. Recent evidence suggests that glycine (or serine)
is a key limiting amino acid in reduced protein [23% crude protein (CP) reduced to 16% CP] corn–soybean meal diets for broiler
chicks. Research with sulfur amino acids has revealed that small excesses of cysteine are growth depressing in chicks fed
methionine-deficient diets. Moreover, high ratios of cysteine:methionine impair utilization of the hydroxy analog of methionine,
but not of methionine itself. A high level of dietary l-cysteine (2.5% or higher) is lethal for young chicks, but a similar level of dl-methionine, l-cystine or N-acetyl-l-cysteine causes no mortality. A supplemental dietary level of 3.0% l-cysteine (7× requirement) causes acute metabolic acidosis that is characterized by a striking increase in plasma sulfate
and decrease in plasma bicarbonate. S-Methylmethionine, an analog of S-adenosylmethionine, has been shown to have choline-sparing activity, but it only spares methionine when diets are deficient
in choline and(or) betaine. Creatine, or its precursor guanidinoacetic acid, can spare dietary arginine in chicks. 相似文献
2.
J. M. Winterbottom 《Ostrich》2013,84(4):182-204
Keffen, R. H. &; Jarvis, M. J. F. 1984. Some measurements relating to Ostrich eggs. Ostrich 55:182-187. Eggs from wild Zimbabwean Ostriches Struthio camelus australis and domesticated South African hybrid birds, were compared. Formulae were tested to determine their accuracy when used to calculate egg weights, surface area and density. Calculated values were compared with some actual measurements. The main motivation for the study was the need to calculate fresh egg weights of wild Ostriches, as an aid to determining weight loss during incubation under natural conditions. Eggs from wild birds were, on average, smaller than those from domesticated birds, even though the wild adults were larger than domesticated birds. However, newly batched chicks from hybrid eggs weighed less than those from wild eggs. 相似文献
3.
Jarvis, M. J. F., Keffen, R. H. & Jarvis, C. 1985. Some physical requirementsfor Ostrich egg incubation. Ostrich 56: 42–51. Eggs from wild and domesticated Ostriches Struthio camelus australis were studied to determine temperature and humidity requirements for successful incubation. Wild eggs in Zimbabwe included some collected and incubated artificially, and others that were naturally incubated until just before hatching. Egg-weight losses during incubation were measured. The eggs artificially incubated at 35 °C to 36°C and 40–42% relative humidity, lost nearly the same weight as did eggs in naturally incubated nests. Comparisons were made between the wild eggs and chicks, and those from domesticated hybrid-strain Ostriches in Bophuthatswana. The discussion outlines some of the remaining problems associated with Ostrich egg incubation. 相似文献
4.
MICHAEL A. GREGG MIKE R. DUNBAR JOHN A. CRAWFORD 《The Journal of wildlife management》2007,71(2):646-651
ABSTRACT Reduced chick survival has been implicated in declines of greater sage-grouse (Centrocercus urophasianus) populations. Because monitoring survival of unmarked sage-grouse chicks is difficult, radiotelemetry may be an effective technique to estimate survival rates, identify causes of mortality, and collect ecological data. Previous studies have used subcutaneous implants to attach radiotransmitters to hatchlings of several species of birds with precocial young. Previous researchers who used subcutaneous implants in free-ranging populations removed chicks from the capture location and implanted transmitters at an alternate site. Because logistics precluded removing newly hatched greater sage-grouse chicks from the field, we evaluated a method for implanting transmitters at capture locations. We captured 288 chicks from 52 broods and monitored 286 radiomarked chicks daily for 28 days following capture during May and June 2001–2002. Two (>1%) chicks died during surgery and we did not radiomark them. At the end of the monitoring period, 26 chicks were alive and 212 were dead. Most (98%, 207/212) radiomarked chick mortality occurred < 21 days posthatch and predation (82%, 174/212) was the primary cause of death. Necropsies of 22 radiomarked chicks did not indicate inflammation or infection from implants, and they were not implicated in the death of any chicks. Fate of 48 chicks was unknown because of transmitter loss (n = 16), radio failure (n = 29), and brood mixing (n = 3). Overall, the 28-day chick survival rate was 0.220 (SE = 0.028). We found that mortalities related to the implant procedure and transmitter loss were similar to rates reported by previous researchers who removed chicks from capture sites and implanted transmitters at an alternate location. Subcutaneous implants may be a useful method for attaching transmitters to newly hatched sage-grouse chicks to estimate survival rates, identify causes of mortality, and collect ecological data. 相似文献
5.
《Archives of animal nutrition》2013,67(5):293-301
Abstract This study was conducted to investigate the effect of dietary conjugated linoleic acids (CLA) on growth performance and immune responses in broiler chicks. A total of 240 day-old Arbor Acre male broiler chicks were randomly allotted into four dietary treatments with different inclusion levels of CLA (0, 2.5, 5.0 or 10.0 g/kg) for six weeks. Growth performance, peripheral blood lymphocyte (PBL) proliferation, lysozyme activity, phagocytic activity (carbon clearance) and serum antibody titers against Newcastle disease virus (NDV) vaccine were examined. There were no significant differences in growth performance among treatments (p > 0.05). Chicks fed CLA diets produced more lysozyme activity in serum than the control group at 2 and 6 weeks of age (p < 0.05). Dietary CLA enhanced the PBL proliferation in response to concanavalin A (ConA) at the age of 42 d (p < 0.05). Phagocytic ability was also affected by dietary CLA and chicks fed CLA diets had faster carbon clearance rate (p < 0.05), but antibody titers to NDV was not influenced by dietary CLA. The results of the study suggested that dietary CLA could enhance innate and cellular immune response in broiler chicks, and not affect the growth performance. 相似文献
6.
C. T. Astley Maberly 《Ostrich》2013,84(1):36-42
Bertram, B. C. R. &; Burger, A. E. 1981. Aspects of incubation in Ostriches. Ostrich 52:36-43. We studied incubation in domesticated Ostriches Struthio camelus in South Africa and wild Ostriches in Kenya. Although the eggs were large, with relatively high thermal capacities, unattended eggs exposed to the sun reached dangerously high temperatures (40,5°C). Experimental exposure of fresh eggs to the sun for seven days prior to incubation greatly reduced the percentage of embryos which developed, and no embryos survived 15 days of exposure. In the wild. Ostriches frequently shade their eggs in the pre-incubation period to prevent overheating. During natural incubation, temperatures in the eggs (range 30,8-33,8°C) and of nest-air (31,9-34,6°C) were remarkably constant, despite the daily ambient fluctuations of air temperatures (17,8-38,9°C). Similarly the humidity of the nest-air (39–52%) was lower and less variable than the ambient air (39–72%). Water loss during 42 days of incubation was 11–12% of initial egg weight and, in addition, early laid eggs lost 3–4% during the 2½-3 week pre-incubation period. The water vapour conductivity and the daily water loss of Ostrich eggs were similar to those of other birds, in proportion to epg size, despite the arid environment inhabited by Ostriches. Some of the constraints on the feeding and breeding behaviour of Ostriches imposed by the physical requirements of their eggs are discussed. 相似文献
7.
《Ostrich》2013,84(3):119-136
Animal population dynamics can be driven by rainfall variability through its influence on habitat suitability, availability and nutritional sufficiency of forage. To understand how rainfall influences ostriches, we related changes in ostrich recruitment in the Mara–Serengeti ecosystem to rainfall. Over a 15-year period, monthly counts of ostriches were made and the number of hatchlings, chicks, hens, cocks, and the size of the groups in which they occurred were recorded. Breeding was bimodal with a major peak in February and a minor peak in October. Ostriches formed larger groups in the wet (4.41 ± 5.17 (mean ± SD), range 1–72, n = 672 groups) than in the dry (2.49 ± 2.70, range 1–29, n = 398) season. The number of hatchlings plus chicks per hen increased across the duration of the study period and with increasing annual and early wet-season rainfall, affecting forage availability and quality. Recruitment was highest at intermediate levels of the five-year average of the late wet-season rainfall, implying that a change in long-term rainfall and habitat suitability would move recruitment away from the optimum. Outstanding adaptations to life in arid environments could make ostriches more resilient than sympatric ungulates if food shortages and water stress became more frequent because of widening climatic variability. 相似文献
8.
A. J. F. K. Craig 《Ostrich》2013,84(4):176-180
Craig, A. J. F. K. 1987. Co-operative breeding in the Pied Starling. Ostrich 58:176-180. Pairs of Pied Starlings Spreo bicolor build the nest, but only the female incubates. After the chicks hatch, subadult and juvenile birds help feed the young. Helpers also feed young after they leave the nest. In most cases parents contribute more than the helpers which may attend several different nests. Associations between members of the same breeding group may persist for up to three successive seasons. 相似文献
9.
Reproductive success of wild Lesser Rheas (Pterocnemia -Rhea- pennata pennata) in north-western Patagonia, Argentina 总被引:1,自引:1,他引:0
We studied the reproductive success of a wild Lesser Rhea population (Pterocnemia -Rhea- pennata pennata) during two reproductive seasons (2004/2005 and 2005/2006) in north-western Patagonia, Argentina. The parameters recorded
included population and nest density, clutch size, hatching success, chick survival (up to 3 months of age) and percentage
of chicks that reached the juvenile stage after the winter. We also estimated the percentage of males that attempted to nest
and of those that were successful (those producing at least one chick), daily nest mortality rates (DNMR) at different stages
of the nesting cycle and the probability that an egg that has been recently laid will produce a chick. On average, both years
pooled, the density of this population of Lesser Rheas was 1.55 ± 0.2 individuals/km2 (SE), nest density was 0.17 ± 0.04 per km
2
, clutch size was 20.8 ± 6.4 eggs, hatching success was 74.4% ± 11.3, Mayfield’s probability of an egg that will produce a
chick was 0.64, chick survival was 65.4% ± 14.5 and percentage of chicks that reached the juvenile stage was 26.3%. Nearly
a quarter of Lesser Rhea males in the population attempted to nest during a breeding season, and the DNMR was significantly
higher during the laying stage (most nest failures were due to anthropogenic disturbances related to livestock raising activities).
Nesting success, hatching success, and chick survival of Lesser Rheas were higher than those of their most closely related
species, the Greater Rhea (Rhea americana), whereas the percentage of chicks that reached the juvenile stage was similar due to high winter mortalities of chicks.
We suggest that the increase in reproductive effort is a strategy of this species to overcome environmental constraints. 相似文献
10.
Yoon SM Kim SY Li KF Yoon BH Choe S Kuo MM 《Applied microbiology and biotechnology》2011,91(3):553-563
Microbial phytases are widely used as feed additive to increase phytate phosphorus utilization and to reduce fecal phytates
and inorganic phosphate (iP) outputs. To facilitate the process of application, we engineered an Escherichia coli appA phytase gene into the chloroplast genome of the model microalga, Chlamydomonas reinhardtii, and isolated homoplasmic plastid transformants. The catalytic activity of the recombinant E. coli AppA can be directly detected in the whole-cell lysate, termed Chlasate, prepared by freeze-drying the transgenic cell paste
with liquid nitrogen. The E. coli AppA in the Chlasate has a pH and temperature optima of 4.5 and 60°C, respectively, which are similar to those described
in the literature. The phytase-expressed Chlasate contains 10 phytase units per gram dry matter at pH 4.5 and 37°C. Using
this transgenic Chlasate at 500 U/kg of diet for young broiler chicks, the fecal phytate excretion was reduced, and the iP
was increased by 43% and 41%, respectively, as compared to those of the chicks fed with only the basal diet. The effectiveness
of the Chlasate to break down the dietary phytates is compatible with the commercial Natuphos fungal phytase. Our data provide
the first evidence of functional expression of microbial phytase in microalgae and demonstrate the proof of concept of using
transgenic microalgae as a food additive to deliver dietary enzymes with no need of protein purification. 相似文献
11.
Minoru Yoshida Hiroshi Hoshii Masanao Matsui 《Bioscience, biotechnology, and biochemistry》2013,77(13):2473-2478
Nutritive value of 4 glycol esters, i.e. ethanediol diacetate, 1,2-propanediol diacetate, 1,3-butanediol diacetate and 1,3-butanediol dioctylate, was estimated biologically by feeding the esters to growing chicks and rats. Energy in the esters taken by both chicks and rats was well utilized, though feed intake of the diets containing the esters at high level tended to decrease. Bitter taste of the esters was suspected to be related to low appetite. The acetates were somewhat volatile and released free acetic acid in the diet during storage. These properties of the acetates makes their use for dietary energy source difficult in practical condition. 相似文献
12.
Akiko Takenaka Yuko Matsumoto Aika Nagaya Kunio Watanabe Shunji Goto Bambang Suryobroto Osamu Takenaka 《Primates; journal of primatology》2000,41(3):299-309
Plasma total cholesterol in free-ranging Japanese macaques (Macaca fuscata) on Koshima islet and in free-ranging long-tailed macaques (Macaca fascicularis) at Pangandaran in Indonesia was found to occur at very low levels compared with captive macaques and humans. Although total
cholesterol levels in captive macaques were lower than humans, differences in HDL cholesterol levels were only small. In both
sexes of wild and captive Japanese macaques, total cholesterol levels decreased from birth through to young adulthood but
then increased in adult females of the captive group. In contrast, the value for adult females of the wild troop remained
at a low level. Low TCH levels in adult females of the wild Japanese macaque troop may be due to a low energy intake and may
have caused a delay in the onset of sexual maturation. Plasma TCH levels increased with the addition of 0.1% dietary cholesterol
over six weeks in captive long-tailed macaques. That the cholesterol value after six weeks was dependent on cholesterol levels
prior to supplementation indicates that captive macaques are slightly saturated with cholesterol. 相似文献
13.
A food web analysis of the juvenile blue crab, Callinectes sapidus, using stable isotopes in whole animals and individual amino acids 总被引:5,自引:0,他引:5
Matthew S. Fantle Ana I. Dittel Sandra M. Schwalm Charles E. Epifanio Marilyn L. Fogel 《Oecologia》1999,120(3):416-426
The stable isotope compositions (C and N) of plants and animals of a marsh dominated by Spartina alterniflora in the Delaware Estuary were determined. The study focused on the juvenile stage of the Atlantic blue crab, Callinectes sapidus, and the importance of marsh-derived diets in supporting growth during this stage. Laboratory growth experiments and field
data indicated that early juvenile blue crabs living in the Delaware Bay habitat fed primarily on zooplankton, while marsh-dwelling
crabs, which were enriched in 13C relative to bay juveniles, utilized marsh-derived carbon for growth. In laboratory experiments, the degree to which juvenile
blue crabs isotopically fractionated dietary nitrogen, as well as the growth rate, depended on the protein quality of the
diet. The range of δ13C of amino acids in laboratory-reared crabs and their diets was almost 20‰, similar to the isotopic range of amino acids of
other organisms. In laboratory studies, the δ13C of nonessential and essential amino acids in the diet were compared to those in juvenile crabs. Isotopic fractionation at
the molecular level depended on diet quality and the crabs' physiological requirements. Comparison of whole-animal isotope
data with individual amino acid C isotope measurements of wild juvenile blue crabs from the bay and marsh suggested a different
source of total dietary carbon, yet a shared protein component, such as zooplankton.
Received: 1 July 1998 / Accepted: 15 March 1999 相似文献
14.
David Glenn Smith 《International journal of primatology》1982,3(4):461-468
Results of previous studies have shown that in captive groups of rhesus monkeys (Macaca mulatto)fathers associate more frequently with their own offspring than with those of other males and that mothers are most permissive
of physical contact between their own infant and a juvenile when that juvenile shares the same father with her infant. These
two observations suggest that the identity of offspring born in captive groups of rhesus monkeys is recognized by at least
some adult members of the group. Consistent patterns of mating among mating seasons might explain this apparent recognition
of offsprings’ paternity. Fathers, for example, might regularly associate with young who maintain a close relationship with
females with whom they have previously mated, and mothers might selectively permit juveniles who maintain a close relationship
with males with whom they have previously mated to associate with their infants. This hypothesis is tested in this paper by
comparing the observed distribution of 70 maternal sibships, members of which were fathered by the same or by different adult
males over a 4-year period in six captive groups of rhesus monkeys, with that distribution expected based on random mating
from season to season. Seasonal mating patterns were found to be random. Preparations are now underway to test this hypothesis
in several free-ranging groups. 相似文献
15.
Disentangling effects of growth and nutritional status on seabird stable isotope ratios 总被引:1,自引:0,他引:1
A growing number of studies suggest that an individual’s physiology affects its carbon and nitrogen stable isotope signatures,
obscuring a signal often assumed to be only a reflection of diet and foraging location. We examined effects of growth and
moderate food restriction on red blood cell (RBC) and feather δ15N and δ13C in rhinoceros auklet chicks (Cerorhinca monocerata), a piscivorous seabird. Chicks were reared in captivity and fed either control (75 g/day; n = 7) or ~40% restricted (40 g/day; n = 6) amounts of high quality forage fish. We quantified effects of growth on isotopic fractionation by comparing δ15N and δ13C in control chicks to those of captive, non-growing subadult auklets (n = 11) fed the same diet. To estimate natural levels of isotopic variation, we also collected blood from a random sample of
free-living rhinoceros auklet adults and chicks in the Gulf of Alaska (n = 15 for each), as well as adult feather samples (n = 13). In the captive experiment, moderate food restriction caused significant depletion in δ15N of both RBCs and feathers in treatment chicks compared to control chicks. Growth also induced depletion in RBC δ15N, with chicks exhibiting lower δ15N when they were growing the fastest. As growth slowed, δ15N increased, resulting in an overall pattern of enrichment over the course of the nestling period. Combined effects of growth
and restriction depleted δ15N in chick RBCs by 0.92‰. We propose that increased nitrogen-use efficiency is responsible for 15N depletion in both growing and food-restricted chicks. δ15N values in RBCs of free-ranging auklets fell within a range of only 1.03‰, while feather δ15N varied widely. Together, our captive and field results suggest that both growth and moderate food restriction can affect
stable isotope ratios in an ecologically meaningful way in RBCs although not feathers due to greater natural variability in
this tissue. 相似文献
16.
《Animal Feed Science and Technology》1999,76(3-4):219-226
The following grain characteristics: protein, arabinoxylan and dietary fibre content, viscosity and water holding capacity of wheat, rye and triticale of different ploidy levels were studied as to their effect on body weight gain (BWG), feed to gain ratio (FCR), apparent metabolizable energy (AMEn), dry matter digestibility (DMD) and apparent protein retention (APR) in young broiler chicks fed isograin and isoprotein diets based on these cereals. Highly significant correlations (p≤0.01) were found between physicochemical and biological quality indicators when all cereals were taken into account. A negative response of chicks to triticale was obtained only when chicks were fed diets containing the tetraploid forms, while the nutrition parameters of chicks fed diets containing the octo- and hexaploid triticale, with rye genome shares of 1 : 3 and 1 : 2, did not differ (p≥0.05) from those fed a wheat diet. Rye diets yielded the lowest BWG, AMEn and DMD and the poorest FCR. The results indicate that as long as the share of the R genome is a minor component of the total triticale genome pool, its antinutritional effect is masked by the wheat genome. The results also indicate that hexaploid triticale can constitute the sole cereal component in the diets of young broiler chicks. 相似文献
17.
Margaret F. Kinnaird 《American journal of primatology》1990,22(4):285-289
Mean gestation for seven free-ranging Tana River crested mangabeys (Cercocebus galeritus galeritus) is 180 days (SE = 4.49). All females showed postconception sexual swellings after the first 2 months of pregnancy, and two of the seven copulated with males at this time. One birth was observed; observations of a second infant began less than 1 hr after birth. Details of parturition are given, with responses of group members to the events. Adult and juvenile females showed more sustained interest in the new infants than adult or juvenile males. 相似文献
18.
Ma?lle Connan Christopher M. R. Kelly Christopher D. McQuaid Bo T. Bonnevie Nigel P. Barker 《Polar Biology》2011,34(6):791-798
The two fuliginous albatross species, Phoebetria fusca (the Sooty albatross, SA) and P. palpebrata (the Light-mantled albatross, LMA), are found breeding close to each other on the Prince Edward Islands (Southern Ocean).
Adults of these two species are easy to identify in the field, but the chicks are difficult to distinguish on the basis of
external morphology, especially at very young ages. Many ecological studies involve sampling of chicks as well as adults,
and accurate field identification of chicks is thus crucial. Traditionally, the extent of the ring of pale feathers around
the eye (eye-ring) has been used to identify the fledglings. The aim of our study was to investigate the utility of characters
associated with the eye-ring (extent, measured as an angle, and colour) for the identification of Phoebetria chicks. This was achieved by comparison of identifications based on morphology, with positive identifications based on DNA
sequence data from the mitochondrial cytochrome b gene. We confirm the value of morphological criteria in distinguishing LMA and SA chicks, and this technique appears to be
accurate in the majority of cases (>80%). However, we recommend using molecular identification for borderline cases (angle
of the eye-ring measuring between 85 and 95°) if independent confirmation of chick identity cannot be obtained (e.g. via observed
feeding interaction with an adult). 相似文献
19.
Rauschenbach IY Gruntenko NE Chentsova NA Adonyeva NV Alekseev AA 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2008,178(1):27-32
The effects of increased levels of dopamine (feeding flies with dopamine precursor, l-dihydroxyphenylalanine) and octopamine (feeding flies with octopamine) on ecdysone 20-monooxygenase activity in young (2 days
old) wild type females (the strain wt) of Drosophila virilis have been studied. l-dihydroxyphenylalanine and octopamine feeding increases ecdysone 20-monooxygenase activity by a factor of 1.6 and 1.7, respectively.
Ecdysone 20-monooxygenase activity in the young (1 day old) octopamineless females of the strain Tβh
nM18
, in females of the strain P845 (precursor of Tβh
nM18
strain) and in wild type females (Canton S) of Drosophila melanogaster have been measured. The absence of octopamine leads to a considerable decrease in the enzyme activity. We have also studied
the effects of juvenile hormone application on ecdysone 20-monooxygenase activity in 2-day-old wt females of D. virilis and demonstrated that an increase in juvenile hormone titre leads to an increase in the enzyme activity. We discuss the supposition
that ecdysone 20-monooxygenase occupies a key position in the regulation of 20-hydroxyecdysone titre under the conditions
that lead to changes in juvenile hormone titre and biogenic amine levels. 相似文献
20.
Megan E. Brown Miranda R. Torkelson Glenn H. Olsen Ashley Krisp Barry K. Hartup 《Zoo biology》2020,39(4):276-280
Endangered whooping cranes (Grus americana) have been produced in captivity for reintroduction programs since the 1980s, using techniques such as artificial insemination, multiple clutching, and captive-rearing to speed recovery efforts. Chicks are often hand-reared (HR) by caretakers in crane costumes, socialized into groups and released together, unlike parent-reared (PR) cranes that are raised individually by a male/female crane pair and released singly. HR cranes historically exhibit greater morbidity rates during development than PR cranes, involving musculoskeletal and respiratory system disease, among others. We hypothesized that HR crane chicks exhibit a higher baseline fecal glucocorticoid metabolite (FGM) concentrations during the development compared with PR chicks. Fecal samples were collected between 15 and 70 days of age from HR (n = 15) and PR (n = 8) chicks to test for differences in FGM concentrations using a radioimmunoassay technique following ethanol extraction for steroids. Linear mixed model analysis suggests increasing age of the chick was associated with an increase in FGM (p < .001). Analysis also supported the interaction between rearing strategy and sex of the crane chick (p < .01). Female PR chicks had greater FGM concentrations than all other groups (PR male, p < .01; HR female, p < .001; and HR male, p < .001). This result suggests that there may be an effect of rearing strategy on stress physiology of whooping crane chicks, especially among females. Further research is needed to investigate whether the FGM concentrations are reflective of true differences in stress physiology of young cranes and whether this may impact health and conservation success. 相似文献