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D W Bailey

Publications and source records attributed to D W Bailey.

At least 19 recordsLinked to original sources
PubMed2005

The effects of weaning beef calves in two stages on their behavior and growth rate.

Four trials were conducted to explore possible advantages of weaning beef calves in two stages compared with the traditional method of weaning by abrupt separation. In the two-stage treatment, calves were prevented from nursing their dam for a period (Stage 1) before their separation (Stage 2). Control calves nursed from their dams until they were separated. Calf weights and behavior were recorded before and after the separation of cows and calves. Following separation, calves weaned in two stages vocalized 96.6% less (P = 0.001) and spent 78.9% less time walking (P = 0.001), 23.0% more time eating (P = 0.001), and 24.1% more time resting (P = 0.001) than control calves. Compared with controls, two-stage calves had lower (P < 0.001) ADG when nursing was deprived (Stage 1), but greater (P < 0.001) ADG during the 7 d following separation. In Trial 3, calves weaned by the two-stage method had greater (P = 0.05) growth rates than control calves for 7 wk after separation, but no treatment effects on ADG were detected (P > 0.38) in Trials 1 and 2. Over the entire study period (before and after separation), ADG did not differ (P > 0.10) for both treatments. In Trial 4, calves weaned in two stages walked 1.3 km/d more (P < 0.05) during the 4-d period when nursing was prevented (Stage 1) and 5.8 km/d less (P < 0.05) during the 4-d period after separation than controls. Differences between treatments were the greatest in the 2 d after separation. On the first day after separation, two-stage calves walked 5.2 +/- 0.5 km/ d, whereas control calves walked 16.7 +/- 3.1 km/d. Calves weaned in two stages were less distressed than calves weaned by the traditional method of abrupt separation based on behavioral data, but overall calf ADG did not differ for either method in this study. Nutritional management of two-stage weaned calves during the nursing-deprived period should be evaluated in future research because poor pasture conditions may have decreased gains by calves weaned by the two-stage method in this study.

Animal Husbandry↗
PubMed2004

Management strategies for optimal grazing distribution and use of arid rangelands.

Application of existing and novel management techniques can alter traditional livestock grazing patterns and significantly improve the sustainability of arid rangelands. Livestock often congregate and heavily graze riparian areas and other sensitive rangeland, while abundant forage remains in other areas. Increasing the uniformity of grazing can help protect fisheries, wildlife habitat, and other vegetative and watershed resources. For years, managers have improved grazing distribution in extensive arid pastures by developing new water sources. In addition, strategic supplement placement can be used to lure cattle to graze areas that typically receive little use. Placement of low-moisture molasses blocks in steeper areas that were far from water increased forage use by 14% at distances up to 600 m from supplement in foothill rangeland. Recent research has examined the potential of breed and individual animal selection to improve grazing distribution patterns. Cattle breeds developed in mountainous terrain utilize rugged rangeland more uniformly than breeds developed in more gentle terrain. In pastures that were grazed by cattle identified as "hill climbers" (previously observed on rugged terrain), more residual vegetation was left on gentle slopes and areas closer to water than in pastures grazed by cattle identified as "bottom dwellers" (previously observed on gentle terrain near water). Cattle may use rugged rangeland more uniformly after weaning and during periods when temperatures are more moderate and the forage is more homogeneous (spring, early summer, and autumn). Herding shows great promise for protecting sensitive rangeland. Preliminary data show that residual riparian forage in pastures where livestock were herded was up to two times higher than in a control pasture. The integration of herding and strategic supplement placement seems to be more effective than herding alone. Many concerns associated with the sustainability of grazing on arid rangelands can be resolved by manipulating livestock grazing behavior through management.

Age Factors↗
PubMed2001

Relationship between terrain use and performance of beef cows grazing foothill rangeland.

A study was conducted on foothills rangeland to determine whether grazing patterns differed among cow breeds and to determine whether there was a relationship between individual grazing patterns and performance of beef cows. Hereford (HH), Tarentaise (TT), 3/4 Hereford x 1/4 Tarentaise (3H1T), 1/2 Hereford x 1/2 Tarentaise (HT), and 1/4 Hereford x 3/4 Tarentaise (1H3T) cows were observed during the summers of 1997 (n = 183) and 1998 (n = 159). Locations of individual cows were recorded two to three times per week during 1.5- to 2.5-h periods in the morning by observers on horseback. Statistical models included cow breed, age, and nursing status. Data from each year were analyzed separately. During 1997 and 1998, nonlactating cows were located at greater (P < 0.05) vertical distances from water than lactating cows. In 1998, nonlactating cows used steeper (P < 0.05) slopes than lactating cows. However, nonlactating cows did not travel as far horizontally from water (P < 0.05) as lactating cows in 1997. Younger cows (3 yr) traveled further (P < 0.05) from water both vertically and horizontally than older cows (5+ yr) in 1997, but not during 1998. Tarentaise and 1H3T cows were observed at greater (P < 0.05) vertical distances from water than HH cows during both years of the study. During 1998, TT and 1H3T cows used steeper (P < 0.05) slopes than HH cows. Using residual correlations, there were no consistent relationships between topographic aspects of individual grazing locations and cow weight, height, and body condition score. In 1997, cows with earlier calving dates and correspondingly heavier calf weaning weights used areas that had greater vertical distances to water; however, in 1998 there were no relationships (P > 0.05) of calving date and weaning weight with cow location. During both years, pregnant and nonpregnant cows used terrain similarly (P > 0.05), which suggests that cow reproductive performance was not related to terrain use. Grazing patterns in foothills rangeland varied among cow breeds. Performance of cows that used more rugged topography was similar to cows using gentler terrain.

Animal Feed↗
PubMed1999

Just a beta....

Traditional implementation of clinical information systems follows a predictable project management process. The selection, development, implementation, and evaluation of the system and the project management aspects of those phases require considerable time and effort. The purpose of this paper is to describe the beta site implementation of a knowledge-based clinical information system in a specialty area of a southeastern hospital that followed a less than traditional approach to implementation. Highlighted are brief descriptions of the hospital's traditional process, the nontraditional process, and key findings from the experience. Preliminary analysis suggests that selection of an implementation process is contextual. Selection of elements from each of these methods may provide a more useful process. The non-traditional process approached the elements of communication, areas of responsibility, training, follow-up and leadership differently. These elements are common to both processes and provide a focal point for future research.

Artificial Intelligence↗
PubMed1995

Calf production by Angus-Hereford and Brahman-Hereford cows on two native rangeland forage systems.

Calf birth weights, weaning weights, and preweaning gain of Simmental-sired calves from Angus-Hereford (AH) and Brahman-Hereford (BH) F1 cows grazing native rangeland (NR) or native rangeland-complementary forage (NRCF) systems in the southern Great Plains mixed prairie were evaluated. Calves from AH dams were heavier (P < .001) at birth than calves from BH dams in both forage systems (40 and 37 kg, respectively). However, birth weights of calves from BH dams were 2 kg heavier (P < .001) in the NRCF fall-calving system. Calves in the NRCF system were 122 d older and heavier (P < .001) than the NR calves at weaning (343 and 256 kg, respectively). During the preweaning period, the NR calves gained faster (P < .001) than the NRCF calves. When calves from both systems were evaluated at 200 d of age, NR calves were heavier (P < .001) than NRCF calves. Calves from BH cows were 8 to 16 kg heavier (P < .001) that calves from AH cows at 200 d of age and at weaning. The increased age at weaning associated with the NRCF did not reduce reproductive efficiency. The NRCF system requires less land than a traditional NR system to support a cow-calf pair and seems to be more economically efficient.

Animal Feed↗
PubMed1986

Genetic programming of development: a model.

Genetic programming of the developmental processes in multicellular organisms is proposed to be so intricate and vitally important that a large set of genes is dedicated solely to this end. It is further proposed that this set can be compartmentalized into subsets on the basis of the changes in gene activities that occur during ontogenesis, and that the genes in each subset transiently control the epigenetic activities of a small group of cells. Automatic subset activation is achieved by the product of a gene in each subset that transfers activity specifically to the subset next in the developmental sequence. This device can generate a unidirectional series of activations that cascade hierarchically through development like toppling dominoes. The model provides a basis for developmental phenomena, such as pattern formation, morphogenesis, and regeneration, and it makes testable predictions at the molecular level.

Animals↗
PubMed1986

Interferon structural genes do not participate in quantitative regulation of interferon production by If loci as shown in C57BL/6 mice that are congenic with BALB/c mice at the alpha interferon gene cluster.

Previous studies have shown that serum interferon (IFN) production in mice is quantitatively influenced by If loci, whose alleles determine high or low production. Although different loci influence IFN production in response to different inducers, such as Newcastle disease virus, Sendai virus, herpes simplex virus type 1, and polyriboinosinic-polyribocytidylic acid, BALB/c mice are in every instance low producers. It was therefore possible that, in addition to If loci, some feature of the BALB/c structural IFN genes contributed to low production. This was examined in the present work, in which IFN production was measured in two strains of C57BL/6 mice congenic with BALB/c at the murine alpha IFN (IFN-alpha) gene cluster on chromosome 4. One line, HW13 (B6.C-H-15c-H-16c-H-20c-H-21c/By) has a BALB/c fragment on chromosome 4 of at least 35 centimorgans which includes the BALB/c IFN-alpha gene cluster and four loci of the brown histocompatibility complex; the other line, HW13J (B6.C-H-15c/By), has a much shorter fragment (about 15 centimorgans), but it also comprises the BALB/c IFN-alpha gene cluster. We show that these mice, carrying the BALB/c IFN-alpha structural genes on a C57BL/6 background, are high IFN producers when stimulated by Newcastle disease virus, Sendai virus, herpes simplex virus type 1, or polyriboinosinic-polyribocytidylic acid. Thus, the low IFN production of BALB/c mice is not directly due to some feature of the IFN-alpha structural genes but is mainly the result of different alleles at If loci.

Alleles↗
PubMed1986

Mandibular-morphogenesis gene linked to the H-2 complex in mice.

The shapes of mandibles from mice of a group of H-2 congenic strains are compared to that of their C57BL/6By background strain. One congenic strain carries a passenger gene that evokes an elongation of the dorsal reach of the condylar process as does an H-2 recombinant congenic strain derived from it. Two other independently derived H-2 congenic strains do not carry such a gene. This indicates that the effective gene resides outside of and on the centromeric side of the H-2 complex on chromosome 17. Reiterated tests demonstrate the reproducibility of this type of genetic analysis.

Animals↗
PubMed1985

Genes on different chromosomes influence the antibody response to bacterial antigens.

B6.C congenic strains of mice, possessing histocompatibility (H) alleles from high responding BALB/cBy (C) mice on the genetic background of low responding C57BL/6By (B6) mice, were assayed for their ability to make an antibody response to Type III pneumococcal polysaccharide (SSS-III) and the alpha(1----3) epitope of bacterial (Leuconostoc) dextran B-1355. The results affirmed that the antibody response to SSS-III is multigenic and that genes making a positive contribution to responsiveness are located on different chromosomes, i.e., chromosomes 1, 3, 4, 5, and 9. At least one other gene also influences responsiveness to SSS-III; it is linked to the H-17 locus, which has not yet been assigned to a specific chromosome. Genes on chromosomes 1, 4, and 5 influence the magnitude of the antibody response to dextran B-1355. Some of these genes may be antigen-specific in their mode of action; however, others may not since they appear to exert a positive influence on the antibody response to both SSS-III and dextran B-1355.

Animals↗
PubMed1982

Immunodominance in the immune response to "multiple" histocompatibility antigens.

Cytotoxic effector T cells putatively specific for multiple non-H-2 histocompatibility (H) antigens were generated by immunizing and boosting C57BL/6 and B6.C-H-2d mice with BALB.B and BALB/c stimulator cells, respectively. The generated effectors were tested for cell-mediated lympholysis on a panel of targets whose BALB/c-derived non-H-2 H antigens were donated by CXB recombinant inbred mice. The spectrum of reactivity of cytotoxic effector T cells with CXB targets demonstrated that the effectors did not recognize multiple H antigens but rather preferentially recognized a single immunodominant non-H 2 antigen. The identity of the immunodominant H antigen was determined by the H-2 genotype of the stimulator cells when (B6 x B6.C-H-2d)F1 cytotoxic effectors were tested. These observations indicate that despite the fact that responders were challenged with more than 40 individual non-H-2 H antigens, they preferentially responded to single immunodominant antigen.

Animals↗
PubMed1981

Genetics of histocompatibility in mice. IV. Detection of certain minor (non-H-2) H antigens in selected organs by the popliteal node test.

The H-Y antigen and minor H antigens defined by eight C57BL/6By (B6) congenic mouse strains were studied for their distribution among 13 different tissues. Antigen expression was detected by implanting B6 recipients with organ fragments from congenic strain donors that had been previously grafted with B6 bone marrow to minimize the number of allogeneic passenger leukocytes. Successfully immunized recipients were identified by the enlargement of their popliteal lymph nodes following footpad challenge with spleen cells of the donor type. No two strains had identical patterns of expression of their distinguishing antigens. The data provide evidence for differences in levels of minor H-antigen expression among different tissues.

Animals↗
PubMed1981

Genetics of histocompatibility in mice. III. Characteristics of the popliteal lymph-node response to minor (non-H-2) H antigens.

The response to spleen cells incompatible at defined histocompatibility, H, loci was studied using the popliteal lymph-node enlargement test to establish its applicability as a method for detecting minor H antigens. This test was able to detect H-2 and H-Y antigens as well as most of the minor H antigens represented by 23 different strains congenic with C57BL/6By. Responses of both naive and immunized recipients were examined, and time-courses of the response were obtained for ten donor strains. These curves revealed that different antigens elicited responses that differed in timing and magnitude of peak enlargements, and that the two parameters were not closely correlated. Both the peak magnitude and the slope of the primary response were correlated with skin-graft rejection, however. The response to individual minor antigens did not appear to be dose-dependent above a threshold. Irradiation of donor cells had strain-dependent effects on the elicited response. Irradiation of recipients appeared to abrogate the primary response but not the responses of previously primed recipients in the combination tested. None of the responses studied had any demonstrable graft-versus-host component.

Animals↗
PubMed1981

Further testing of several strains of mice with respect to detection of H - 2 antigens on neonatal erythrocytes.

In previous experiments the existence of two types of neonatal erythrocytes was confirmed in different inbred and congenic strains of mice. Erythrocytes of the "early" type were agglutinable by the appropriate antisera on the day of birth; the "late" type erythrocytes were not agglutinable until the third day of postnatal life. Results of earlier studies on segregating generations supported the proposed "remote-cis-effect" model for genetic control of H-2 antigen detectability in newborns. We report on tests that bear further upon this phenomenon.

Animals↗