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Biomedical subjects

E G Buss

Publications and source records attributed to E G Buss.

At least 19 recordsLinked to original sources
PubMed1996

Cryopreservation of rooster semen in thirteen and sixteen percent glycerol.

Semen from Barred Plymouth Rock roosters was cryopreserved with glycerol concentrations of 13 and 16% in a microprocessor-controlled freezer. Thawing and deglycerolation were facilitated by the use of an improved microprocessor-controlled thawing device and high speed dialyzer. Deglycerolated semen (100 mu L; 192 and 154 million sperm, respectively, for the 13 and 16% glycerol concentration) was inseminated into Single Comb white Leghorn hens. Three inseminations were done at 4-d intervals. Eggs were collected for 10 d starting 1 d after the first insemination, and incubated for 4th d. Fertility was determined by candling after the 4th d. Fertility measurements of 62.4 and 65% were obtained from the sperm frozen in 13 and 16% glycerol concentrations, respectively, for the 10-d period.

Animals↗
PubMed1993

Cryopreservation of rooster sperm.

Successful cryopreservation of sperm requires: 1) selection of proper diluent; 2) selection of the best cryoprotectant; 3) determination of freezing and thawing rates for optimum retention of fertilization potential; and 4) removal of any materials deleterious to fertility (e.g., glycerol) before insemination. An economically useful process must allow recovery of sperm with sufficient fertilization capacity to enable maximum use of any given superior male. A series of experiments tested a novel semen freezing container (BioPore CryoCell container) having physical characteristics that permit reproducible freezing and thawing plus facile removal of glycerol from the sample after processing. Experiments tested the effect of: a) residual glycerol; b) initial glycerol concentrations on retention of fertility when samples were frozen and thawed at 6 C/min; c) Beltsville Poultry Semen Extender and Minnesota A buffers used during the dialysis procedure; and d) dialysis time. Respectively, the results were: a) .8% (vol/vol) reduced fertility by 5 to 10%; b) 12% glycerol was superior to 10% and 8% glycerol; c) no difference was observed between the two buffers; and d) 90 and 120 min were both superior to 60 min. Numerous pools of rooster sperm cryopreserved in CryoCell containers and dialyzed after thawing in a prototype BioStore environmental control chamber for 90 or 120 min resulted in a mean fertility of 55.6%. This mean fertility of frozen-thawed sperm was based on 3,263 eggs laid by 400 hens on Days +1 through 9 after inseminations on Days -1, 2, and 5. It is likely that broiler stocks might have lower fertility than that obtained from the Barred Plymouth Rock males and the Single Comb White Leghorn females used in these studies. Nevertheless, the procedure described is the first to consistently result in > 50% fertilized eggs as a result of conventional intravaginal insemination (< 200 x 10(6) sperm in 100 microL extender) of sperm processed after thawing by a procedure amenable to the scaleup required for commercial applications.

Animals↗
PubMed1985

Arterial blood gas, pH, and bicarbonate values in laying hens selected for thick or thin eggshell production.

Bicarbonate, pH, carbon dioxide partial pressure (pCO2), and oxygen partial pressure (pO2) were measured in blood samples collected anaerobically from the brachial arteries of domestic fowl from lines selected for thick (TK) or thin (TN) eggshell production. The blood values of TK and TN hens were compared 6 hr prior to oviposition and continued at 2-hr intervals until 10 hrs postoviposition. Percent shell values were measured for eggs laid 2 days prior to and during blood sampling. Hens with TK shells had significantly (P less than .001) higher percent shell values than hens with TN shells. The measured blood parameters (bicarbonate, pH, pCO2, and pO2) did not differ significantly (P greater than .05) when TK and TN hens were compared at the time of oviposition. However, between 2 and 6 hr postoviposition, TN hens had significantly lower blood pH, pO2, and bicarbonate than did TK hens. Arterial pCO2 tended to be higher in TN hens than in TK hens, but this difference was significant only at 6 hr preoviposition. These results show that TN hens develop metabolic acidosis relative to TK hens during the first 6 hr postoviposition.

Acidosis↗
PubMed1984

Bone parameters of thick and thin eggshell lines of chickens.

Comparative measurements of bone parameters were made on chickens from thick and thin eggshell lines that were maintained on a normal diet containing 3.5% calcium, injected i.v. with 45CaCl2 and sacrificed 30 min later. There were no significant differences between shell lines for the following measurements on the left femur: specific gravity, ash wt, total calcium, percent calcium and 45Ca content. There was deposition of 45Ca in the femur of all hens--even those in the process of eggshell formation. Skeletal metabolism was not a limiting factor in determining whether a hen produced a thick or thin eggshell.

Animals↗
PubMed1984

Blood ionic calcium response to hypocalcemia in the chicken induced by ethyleneglycol-bis-(B-aminoethylether) -N,N'-tetraacetic acid: role of the parathyroids.

Eight groups of cockerels were used to test an ethyleneglycol-bis-(B-aminoethylether)-N,N'-tetraacetic acid (EGTA) challenge as a possible means for estimating parathyroid function and responsiveness in birds. Intravenous injections of EGTA significantly depressed blood ionic calcium concentrations (hypocalcemia), and the recovery from this hypocalcemia was dependent upon the presence of parathyroid hormone (PTH). However, it also was demonstrated that a surge of PTH is not necessary for recovery from the EGTA-induced hypocalcemia. Therefore, in the bird, the EGTA challenge is a test of the ability of PTH target tissues (bone or soft tissues) to buffer ionic calcium in the blood. The EGTA challenge is not a quantitative means of testing parathyroid gland function or responsiveness.

Animals↗
PubMed1984

Blood ionic calcium responses of hens from thick-shell and thin-shell lines to ethyleneglycol-bis-(B-aminoethylether)-N,N'-tetraacetic acid injections.

Experiments were conducted on laying and nonlaying hens from genetically selected lines that produce thick (TK) or thin (TN) eggshells. At 44 weeks of age, TK layers exhibited significantly higher total plasma calcium concentrations than TN layers. Total plasma calcium concentrations were not significantly different between TK and TN layers at 80 weeks of age, reflecting an effect of aging on total plasma calcium. Intravenous injections of ethyleneglycol-bis-(B-aminoethylether-N,N'-tetraacetic acid (EGTA) were administered to TK and TN layers at 44 weeks of age and to TK and TN layers and nonlayers at 80 weeks of age. EGTA is a calcium chelating agent that creates hypocalcemia when injected intravenously. Laying hens of both lines and at both ages exhibited a similar degree of hypocalcemia during EGTA injections, and a similar rate of recovery to normocalcemia was noted after cessation of EGTA administration. Nonlayers were unable to recover from the EGTA-induced hypocalcemia. Because the pattern of calcium depression and recovery during and after the EGTA challenge has been shown to be associated with the capacity of parathyroid hormone-sensitive target tissues to buffer blood ionized calcium, it was concluded that the capacity to buffer ionized calcium by these target tissues is similar in TK and TN layers. However, nonlayers have a restricted capacity to buffer blood ionic calcium.

Animals↗
PubMed1984

A comparison of bone length and bone weight with embryo weight in chondrodystrophic and normal Beltsville small white turkey embryos.

Chondrodystrophic and normal 24-day old embryos obtained from matings of known heterozygotes (Ch/ch) of the Beltsville Small White turkey stock were compared for bone lengths and for bone weights as a percent of embryo weights. Bone and embryo weights were less in the chondrodystrophic embryos, and the bone weights were reduced proportionally more than embryo weights. The lengths of the humeri and tibiotarsi were shorter in chondrodystrophic embryos, and the tibiotarsi were shortened more than the humeri.

Animals↗
PubMed1983

Blood pressure of chickens selected for leanness or obesity.

Four lines of chickens selected for divergence in body weight followed by selection for obesity or leanness within each body weight line were used as a genetic model to determine the relationship of blood pressure and obesity. Forty females, 10 of each line, and 20 males, 10 from the heavy-weight obese and 10 from the light-weight obese, were used. Direct measurements of blood pressure were obtained from the left brachial artery of seven-month old birds. Systolic, diastolic, and mean blood pressures were recorded in this study. The systolic, diastolic, and mean blood pressure for the light-obese and light-lean females did not differ significantly; likewise, no difference was found for these three parameters in the heavy-obese and heavy-lean females. However, the blood pressures in the light-obese and light-lean lines were significantly higher than the heavy-obese and heavy-lean lines. Also, the blood pressures of the light-obese males were higher than those of the heavy-obese males; both male lines exceeded the females of the two respective lines.

Animals↗
PubMed1982

A comparison of the in vitro lipogenic rates and other physiologic parameters in two strains of lean and obese chickens.

Selection for abdominal fat pad size in mature hens has yielded two divergent strains of lean and obese chickens. The females in the obese line have been shown to have a greater amount of total body lipid by six weeks of age. Liver slices from 6- and 17-week old obese chickens incorporated significantly more 3H2O into extracted fractions of total lipid and saponified fatty acids. Palmitate esterification by abdominal fat pad slices from 12-week old pullets was the same for both strains when activity was expressed per unit weight of tissue. The twofold difference in size between the lean and obese fat pads at this age, however, indicates a significantly greater degree of total esterification in the obese birds. At 6-, 12-, and 17-weeks of age, the two lines exhibited similar concentrations of plasma glucose, total protein, and triglycerides.

Adipose Tissue↗
PubMed1982

The developmental characteristics of two strains of chickens selected for differences in mature abdominal fat pad size.

Genetic selection for mature abdominal fat pad size has resulted in establishing lean and obese lines of chickens. Although the selection was made with mature hens, studies with the progeny showed that obesity could develop as early as 6 weeks of age. Body weights in the two lines diverged by 7 weeks of age although significant differences in feed intake were not seen until the fourteenth week. A pair-feeding study was conducted from 7 through 17 weeks of age. The results showed that pair-feeding greatly reduced the lipid deposited in the obese line. The two strains differed substantially in carcass lipid content, but the proportion of total body lipid contributed by the carcass, viscera, and abdominal fat pad was similar in both lines.

Adipose Tissue↗
PubMed1981

The role of oligosaccharide in transport of egg yolk riboflavin-binding protein to the egg.

The carbohydrate portion of chicken egg yolk riboflavin-binding protein was examined to determine its role in the biological activity of the protein. Yolk RBP was found to contain 5--6 mannose, five galactose, 12 N-acetylglucosamine and four sialic acid residues. Specific modifications of the oligosaccharide moiety were performed which included removal of sialic acid by mild acid hydrolysis, oxidation of galactose by galactose oxidase, and removal of N-acetylglucosamine and galactose residues by a mixture of glycosidases from Aspergillus niger. All of the modified proteins retained the ability to bind riboflavin although their capacities were lower than that of native yolk RBP. Circular dichroism of the modified yolk RBP samples showed changes in the near ultraviolet, but molar ellipticities in the far ultraviolet displayed only minor variations indicating no gross structural changes. All samples cross-reacted with RBP-specific antiserum. The plasma half-life of 125I-labeled yolk RBP was 62 min. Each of the modified samples was cleared more rapidly from the blood than native yolk RBP. Removal of sialic acid decreased the half-life of yolk RBP by 31%, while the other modifications decreased the half-life by as much as 60%. During a 10-day period following injection of 125I-labeled yolk RBP, 5.9% of the labeled protein was recovered from egg yolk. Relative to native yolk RBP, the transport of asialo-yolk RBP was decreased by 82%. The other modifications resulted in even less transport to the egg, the lowest being glycosidase-treated asialo-yolk RBP which was decreased by over 99%. By comparison of samples with similar clearance times, a positive correlation was made between sialic acid and ovarian transport.

Animals↗
PubMed1981

Thiamin deposition in eggs is not dependent on riboflavin-binding protein.

The thiamin content of eggs laid by hens possessing no, one or two functional genes for riboflavin-binding protein is unaffected by the genotype. This does not support the hypothesis of Muniyappa & Adiga [Biochem. J. (1979) 177, 887-894] that the deposition of thiamin-binding protein is coupled to the deposition of riboflavin-binding protein.

Animals↗
PubMed1981

The chromosomes of turkey embryos during early stages of parthenogenetic development.

In the early stages of parthenogenetic development in turkey eggs, many blastoderms are mosaics of haploid, diploid and polyploid cells. The genome composition of these blastoderms can be identified by C-banding. They may be generally described as either A-Z/2A-ZZ/nA-nZ or A-W/2A-WW/nA-nW and are found in a nearly 1:1 ratio. The blastoderms showing the W body (W+) become lethal within two days of incubation. The haploid cell proportion decreases rapidly during the early stage of development, and, as haploid cells decrease, the proportion of polyploid cells appears to increase. At six days of incubation, various kinds of parthenogenetic development can be observed. Their genome compositions are either diploid (2A-ZZ) or mosaic (A-Z/2A-ZZ). These findings suggest that diploid parthenogenesis occurs by either suppression of meiosis II or chromosome doubling some time after the first cleavage division. The frequent occurrence of mosaic blastoderms indicates that the majority, if not all, of the parthenogenetic embryos initiate their development in haploid ova.

Animals↗
PubMed1980

Avian riboflavinuria--XI. Immunological quantitation of cross-reacting liver proteins from normal, heterozygous, and mutant hens.

A genetic defect, avian riboflavinuria, was discovered in a strain of Single Comb White Leghorn chickens and has been attributed to the absence of functional riboflavin-binding protein (RBP). The ratio of functional RBP in blood, egg yolk, and egg white was 2 (RdRd) : 1 (Rdrd) : 0 (rdrd). The present study on non-riboflavin-binding, cross-reacting proteins (CRPs) from RdRd, Rdrd, and rdrd hens involved partial purification and immunochemical quantitation using antiserum to RBP. Immunoreactivities (microgram/g liver) of CRPs were found to be 2.6 (RdRd) : 1.3 (Rdrd) : 0.02 (rdrd). Reciprocal cross-reactions were observed with rabbit sera directed toward both RdRd CRP and RBP. Reaction of the CRPs with antiglycopeptide serum (specific for beta-linked galactose) showed that they were glycosylated. CRPs from RdRd and Rdrd hens had relative antigenicities similar to that of RBP (Krel approximately or equal to 1), while rdrd CRP had a significantly lower antigenicity (Krel = 0.003). The molecular weights of the CRPs as determined by SDS-polyacrylamide gel electrophoresis were as follows: RdRd = 31,6000, Rdrd = 30,900, and rdrd = 27,500. The molecular weight of egg yolk RBP was 34,7000 by the same method. The conclusion is drawn that the rd gene codes for a nonfunctional mutant protein, possibly an "altered precursor", that is different from RBP.

Animals↗
PubMed1980

Ten genetic loci in the chicken that contain structural genes for endogenous avian leukosis viruses.

Our interpretation of the results presented here may be summarized as follows: (1) Endogenous viral genes can be located at any of a large number of sites in the chicken chromsome. (2) Different phenotypes of viral gene expression are observed, depending on the nature of the viral sequences at a given site and depending on whether the necessary sequence elements for expression are present. (3) Endogenous viral genes perform no essential function in the chicken.

Alpharetrovirus↗