Antibacterial and Antifungal Agents in Diets for Laying and Breeding Hens

In general, the use of arsenic acids (arsanilic acid and 3-nitro 4 hydroxyphenylarsonic) in the diets of laying hens has been observed as a slight increased rate of egg production or improved feed efficiency. However, detrimental effects can be observed with each of the arsenic acids when fed in exceptionally high energy diets. But on average, a 3% improvement in egg production has been observed. Data obtained over the past 2 years at this laboratory with the use of several antibiotics including penicillin, oleandomycin, oxytetracycline, chlortetracycline, and streptomycin plus arsanilic acid, the nitrofurans (furazolidone and nitrofurazone) and nystatin in diets for laying and breeding hens will be reported

Feeding Poultry for Profit

Feeding poultry for profit involves essentially the use of top quality stock, proper management and care, proper facilities, and last, but certainly not least important, a good feed. The feed accounts for well over 50 per cent of the cost of poultry, meat and egg production, hence its importance cannot be considered lightly. A good feed supplies all of the essential nutrients in the required amounts for each type of production

Methionine and Related Compounds and Selenium Poisoning

The problem of selenium poisoning has been known for many years, but the mechanism by which this element exerts its toxicity has not been clarified. As a result, what control measures are now available are of an empirical nature, and they fail to the give the most desirable protection. In search of a better control mechanism, the role of compounds containing biologically active methyl groups has been studied. Some experimental work indicated that these types of compounds might indeed be involved in the metabolism of selenium. However, not all workers’ data were in agreement, and it was felt that further studies were needed

Reproductive Performance of Chickens as Influenced by Antibiotics in the Diet

Many workers have reported on the failure of antibiotic supplementation to improve the performance of hens already in high egg production. On the other hand, reports have appeared which indicated that under similar conditions the antibiotics have favorably affected the performances of laying pullets. The experiments of this study were designed to make it possible to determine effects of supplementation with antibiotics as well as to compare various feeding systems

Effects of Energy and Protein Levels and Antibiotics on Growing Turkeys

Much attention has been given recently to the use and value of high energy rations for poultry, particularly for broilers and to a limited extent for laying hens and young turkeys. Although the general fundamentals of the findings may appear applicable in formulation of diets for growing turkeys beyond the age of 8 weeks, little direct evidence has been available to justify such application. Actually, there is some evidence to indicate that the higher energy diets may not necessarily promote a more rapid rate of gain for the older birds. The current study considers the possible effects of protein and antibiotics on the problem

Penguins leaving the pole: bound-state effects in B decaying to K* + photon

Applying perturbative QCD methods recently seen to give a good description of the two body hadronic decays of the B meson, we address the question of bound-state effects on the decay B into K* + gamma. Consistent with most analyses, we demonstrate that gluonic penguins, with photonic bremsstrahlung off a quark, change the decay rate by only a few percent. However, explicit off-shell b-quark effects normally discarded are found to be large in amplitude, although in the standard model accidents of phase minimize the effect on the rate. Using an asymptotic distribution amplitude for the K* and just the standard model, we can obtain a branching ratio of a few times 10^{-5}, consistent with the observed rate.Comment: 12 pages. U. of MD PP \#94-129; DOE/ER/40762-033; WM-94-104. LaTeX, One figure, available by fax or pos

Analytical time-like geodesics

Time-like orbits in Schwarzschild space-time are presented and classified in a very transparent and straightforward way into four types. The analytical solutions to orbit, time, and proper time equations are given for all orbit types in the form r=r(\lambda), t=t(\chi), and \tau=\tau(\chi), where \lambda\ is the true anomaly and \chi\ is a parameter along the orbit. A very simple relation between \lambda\ and \chi\ is also shown. These solutions are very useful for modeling temporal evolution of transient phenomena near black holes since they are expressed with Jacobi elliptic functions and elliptic integrals, which can be calculated very efficiently and accurately.Comment: 15 pages, 10 figures, accepted by General Relativity and Gravitatio

Perturbative QCD and factorization of coherent pion photoproduction on the deuteron

We analyze the predictions of perturbative QCD for pion photoproduction on the deuteron, gamma D -> pi^0 D, at large momentum transfer using the reduced amplitude formalism. The cluster decomposition of the deuteron wave function at small binding only allows the nuclear coherent process to proceed if each nucleon absorbs an equal fraction of the overall momentum transfer. Furthermore, each nucleon must scatter while remaining close to its mass shell. Thus the nuclear photoproduction amplitude, M_{gamma D -> pi^0 D}(u,t), factorizes as a product of three factors: (1) the nucleon photoproduction amplitude, M_{gamma N_1 -> pi^0 N_1}(u/4,t/4), at half of the overall momentum transfer, (2) a nucleon form factor, F_{N_2}(t/4), at half the overall momentum transfer, and (3) the reduced deuteron form factor, f_d(t), which according to perturbative QCD, has the same monopole falloff as a meson form factor. A comparison with the recent JLAB data for gamma D -> pi^0 D of Meekins et al. [Phys. Rev. C 60, 052201 (1999)] and the available gamma p -> pi^0 p data shows good agreement between the perturbative QCD prediction and experiment over a large range of momentum transfers and center of mass angles. The reduced amplitude prediction is consistent with the constituent counting rule, p^11_T M_{gamma D -> pi^0 D} -> F(theta_cm), at large momentum transfer. This is found to be consistent with measurements for photon lab energies E_gamma > 3 GeV at theta_cm=90 degrees and \elab > 10 GeV at 136 degrees.Comment: RevTeX 3.1, 17 pages, 6 figures; v2: incorporates minor changes as version accepted by Phys Rev

Complete chloroplast genome sequences of Drimys, Liriodendron, andPiper: Implications for the phylogeny of magnoliids and the evolution ofGC content

The magnoliids represent the largest basal angiosperm clade with four orders, 19 families and 8,500 species. Although several recent angiosperm molecular phylogenies have supported the monophyly of magnoliids and suggested relationships among the orders, the limited number of genes examined resulted in only weak support, and these issues remain controversial. Furthermore, considerable incongruence has resulted in phylogenies supporting three different sets of relationships among magnoliids and the two large angiosperm clades, monocots and eudicots. This is one of the most important remaining issues concerning relationships among basal angiosperms. We sequenced the chloroplast genomes of three magnoliids, Drimys (Canellales), Liriodendron (Magnoliales), and Piper (Piperales), and used these data in combination with 32 other completed angiosperm chloroplast genomes to assess phylogenetic relationships among magnoliids. The Drimys and Piper chloroplast genomes are nearly identical in size at 160,606 and 160,624 bp, respectively. The genomes include a pair of inverted repeats of 26,649 bp (Drimys) and 27,039 (Piper), separated by a small single copy region of 18,621 (Drimys) and 18,878 (Piper) and a large single copy region of 88,685 bp (Drimys) and 87,666 bp (Piper). The gene order of both taxa is nearly identical to many other unrearranged angiosperm chloroplast genomes, including Calycanthus, the other published magnoliid genome. Comparisons of angiosperm chloroplast genomes indicate that GC content is not uniformly distributed across the genome. Overall GC content ranges from 34-39%, and coding regions have a substantially higher GC content than non-coding regions (both intergenic spacers and introns). Among protein-coding genes, GC content varies by codon position with 1st codon > 2nd codon > 3rd codon, and it varies by functional group with photosynthetic genes having the highest percentage and NADH genes the lowest. Across the genome, GC content is highest in the inverted repeat due to the presence of rRNA genes and lowest in the small single copy region where most NADH genes are located. Phylogenetic analyses using maximum parsimony and maximum likelihood methods were performed on DNA sequences of 61 protein-coding genes. Trees from both analyses provided strong support for the monophyly of magnoliids and two strongly supported groups were identified, the Canellales/Piperales and the Laurales/Magnoliales. The phylogenies also provided moderate to strong support for the basal position of Amborella, and a sister relationship of magnoliids to a clade that includes monocots and eudicots. The complete sequences of three magnoliid chloroplast genomes provide new data from the largest basal angiosperm clade. Evolutionary comparisons of these new genome sequences, combined with other published angiosperm genome, confirm that GC content is unevenly distributed across the genome by location, codon position, and functional group. Furthermore, phylogenetic analyses provide the strongest support so far for the hypothesis that the magnoliids are sister to a large clade that includes both monocots and eudicots