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Diffusion MRI tractography is the only noninvasive method to measure the structural connectome in humans. However, recent validation studies have revealed limitations of modern tractography approaches, which lead to significant mistracking caused in part by local uncertainties in fiber orientations that accumulate to produce larger errors for longer streamlines. Characterizing the role of this length bias in tractography is complicated by the true underlying contribution of spatial embedding to brain topology. In this work, we compare graphs constructed with ex vivo tractography data in mice and neural tracer data from the Allen Mouse Brain Connectivity Atlas to random geometric surrogate graphs which preserve the low-order distance effects from each modality in order to quantify the role of geometry in various network properties. We find that geometry plays a substantially larger role in determining the topology of graphs produced by tractography than graphs produced by tracers. Tractography underestimates weights at long distances compared to neural tracers, which leads tractography to place network hubs close to the geometric center of the brain, as do corresponding tractography-derived random geometric surrogates, while tracer graphs place hubs further into peripheral areas of the cortex. We also explore the role of spatial embedding in modular structure, network efficiency and other topological measures in both modalities. Throughout, we compare the use of two different tractography streamline node assignment strategies and find that the overall differences between tractography approaches are small relative to the differences between tractography- and tracer-derived graphs. These analyses help quantify geometric biases inherent to tractography and promote the use of geometric benchmarking in future tractography validation efforts.

Mammalian neurons operate at length scales spanning six orders of magnitude; they project millimeters to centimeters across brain regions, are composed of micrometer-scale-diameter myelinated axons, and ultimately form nanometer scale synapses. Capturing these anatomical features across that breadth of scale has required imaging samples with multiple independent imaging modalities. Translating between the different modalities, however, requires imaging the same brain with each. Here, we imaged the same postmortem mouse brain over five orders of spatial resolution using MRI, whole brain micrometer-scale synchrotron x-ray tomography (μCT), and large volume automated serial electron microscopy. Using this pipeline, we can track individual myelinated axons previously relegated to axon bundles in diffusion tensor MRI or arbitrarily trace neurons and their processes brain-wide and identify individual synapses on them. This pipeline provides both an unprecedented look across a single brain's multi-scaled organization as well as a vehicle for studying the brain's multi-scale pathologies.

Summary: The incidence of human papilloma virus (HPV)-associated head and neck squamous cell carcinoma (HNSCC) is increasing and implicated in more than 60% of all oropharyngeal carcinomas (OPSCCs). Although whole-genome, transcriptome, and proteome analyses have identified altered signaling pathways in HPV-induced HNSCCs, additional tools are needed to investigate the unique pathobiology of OPSCC. Herein, bioinformatics analyses of human HPV(+) HNSCCs revealed that all tumors express full-length E6 and identified molecular subtypes based on relative E6 and E7 expression levels. To recapitulate the levels, stoichiometric ratios, and anatomic location of E6/E7 expression, we generated a genetically engineered mouse model whereby balanced expression of E6/E7 is directed to the oropharyngeal epithelium. The addition of a mutant PIK3CAE545K allele leads to the rapid development of pre-malignant lesions marked by immune cell accumulation, and a subset of these lesions progress to OPSCC. This mouse provides a faithful immunocompetent model for testing treatments and investigating mechanisms of immunosuppression. : Carper et al. present the “iKHP” mouse, in which HPV16 oncogenes are inducibly activated in vivo in a tissue-specific and temporal manner. Oropharyngeal-specific expression of E6/E7 with PIK3CAE545K in these mice promotes the development of premalignant lesions marked by immune cell infiltration, but only a subset spontaneously convert to OPSCC. Keywords: genetically engineered mouse model, GEMM, human papilloma virus, HPV, HPV16, head and neck squamous cell carcinoma, HNSCC, oropharyngeal squamous cell carcinoma, OPSCC, immunocompetent, tumorigenesis, oncogene, tumor suppressor, LumiFluor

There is a high incidence of rotator cuff injuries in the adult population, and there are well-described techniques for the most common types. Full-thickness transtendon rotator cuff tears are an uncommon injury, and there is limited literature on the appropriate treatment. These rare injuries are important to recognize due to the risk of repair failure using traditional techniques. Simply anchoring the medial portion of the tendon to the anatomic footprint after debriding the lateral tendon risks overtensioning the tendon. Previous techniques share the problem of poor visualization and difficulty passing sutures from standard portals. This technique uses 2 portals, the well-described Neviaser portal and a posterior superior accessory portal. Through these 2 portals, the goal is to increase visualization, increase ease of passing sutures, and avoid debridement of intact tendon.

The behaviours, ecologies and morphologies of pangolins make them challenging to survey and monitor, and non-targeted wildlife surveys have not produced robust status assessments, especially where population densities are low because of overexploitation. To inform the development of feasible survey and monitoring techniques for pangolins, we conducted a systematic review of all traceable efforts used to survey and monitor pangolins to date: 87 articles were included in the review. Pitfalls of current approaches are discussed and recommendations made on suitable methods. Recommendations include the use of mark-recapture for burrow-dwelling species, community interviews, sign-based surveys in arid and open habitats, detection dog teams, and targeted camera-trapping. Occupancy sampling using camera-traps could be used to monitor some pangolin populations, particularly ground-dwelling species, but the rarity of all species makes it uncertain whether this would provide enough data for monitoring; combinations of methods used within an occupancy sampling framework are likely to be the most effective. There will be many circumstances where direct monitoring of a population at a site, to a level that will generate precise data, is not financially viable nor the best use of conservation resources. In many sites, particularly in Asia, pangolins are too rare as a result of overexploitation, and/or occur in inaccessible areas where significant resources will be needed to implement a targeted monitoring programme. Under such circumstances, the use of proxy variables, including status of other hunting-sensitive species that are easier to record, in combination with enforcement or patrol data and/or community interviews, is likely to be the most cost-effective method for assessing the impact of conservation interventions on pangolin status. The publication of incidental observations and survey ‘by-catch’ would significantly improve understanding of pangolin status and ecology, and therefore how best to identify, conserve and monitor priority populations.

Irreparable rotator cuff tears are a complicated problem, and current treatment options include nonoperative rehabilitation, debridement with or without a biceps tenotomy, tuberoplasty, partial rotator cuff repair, patch augmentation, biodegradable spacers, tendon transfer, and reverse shoulder arthroplasty. Arthroscopic superior capsular reconstruction is a more recent technique that is gaining popularity for use in irreparable rotator cuff tears. However, this surgery can be technically complicated. The purpose of this technique is to increase reproducibility and simplify a complicated procedure by addressing the current challenges of previous techniques.

Biceps tenodesis remains a popular choice for treating anterior shoulder pain in the setting of primary biceps tendinitis or biceps pain due to concomitant glenohumeral joint pathology. A variety of surgical approaches and fixation construct options are available for biceps tenodesis. The advantages of an all-arthroscopic biceps tenodesis include anatomic maintenance of the length-tension relation with strength preservation and improved cosmetic results. This technique can be technically challenging but allows for a minimally invasive approach to anchor the biceps. In this Technical Note, we describe a suprapectoral biceps tenodesis using an all-arthroscopic approach in the setting of concomitant rotator cuff repair. This technique offers a viable alternative to the open subpectoral biceps tenodesis.

The objective of the present study was to compare carnosine levels in tissues of broilers under stress conditions with those of broilers under nonstress conditions. Blood heterophil:lymphocyte ratio and corticosterone levels were measured as indicators of the level of stress. Corticosterone levels of stressed broilers (24,358.67 pg/mL) were 10-fold higher (P = 0.002) than those of nonstressed broilers (2,275.46 pg/mL). However, no difference (P = 0.29) was found in heterophil:lymphocyte ratio of nonstressed (0.29) and stressed (0.31) birds. Carnosine content in breast of stressed birds (17.39 mg/g) was 10 times higher (P = 0.005) than that of nonstressed birds (1.85 mg/g). Carnosine content in thigh of stressed birds (21.25 mg/g) was approximately 2-fold higher (P = 0.001) than that of nonstressed birds (11.10 mg/g). Carnosine content in brain of stressed birds did not differ (P = 0.82) from that of nonstressed birds. Based on the present study, muscle carnosine recovery levels increase during short-term stress, whereas levels in the brain are not affected.

With the inception of the modem era of avian immunology in the mid-1950s following the discovery of the role of the bursa of Fabricius (BF), steady and persistent research has been conducted by scientists. Findings that have advanced our knowledge of humoral immunity (HI) include the distinct role of B cells in antibody production, explanation of antibody diversity by gene rearrangement and conversion, identification of a bursal secretory dendritic cell and dendritic cells of the spleen, characterization of cytokine factors, and mapping of MHC class II genes. Numerous experiments have been conducted to evaluate the HI responses of poultry through antibody titer determination and quantitation of immunoglobulin concentrations in the humors. Antibody studies have included the genetics of HI regarding both quantity and persistence of responses as influenced by multiple genes and MHC haplotypes. In the past decade, emergence of monoclonal antibody reagents to identify cell surface markers on B cells and accessory cells has allowed for discrimination of HI functions of cells by immunohistochemistry, flow cytometry, and other techniques. The signaling mechanisms of avian B cells are becoming better understood. Continued work in avian immunity has led to more advances in identification, characterization, and gene sequencing of important cytokines. Additional work is required to identify and sequence genes for many more cytokines that have direct effects on B cells. A brief history of research published on avian B cells is presented with an examination of some of the important research findings reported in recent years.

A monoclonal antibody (4C7/2E4) that binds to an antigen located on the midpiece of turkey spermatozoa has been produced and characterized. The antibody was also reactive to antigens on the midpiece of chicken, Japanese quail, and bobwhite quail spermatozoa but was unreactive to spermatozoa from guinea fowl, human, horse, boar, and bull. Immunogold transmission electron microscopy of turkey spermatozoa showed that the antibody was associated with the outer mitochondrial membrane. Titratable antibody binding was observed for extracts of turkey spermatozoa and isolated mitochondria. The antibody did not recognize proteins separated by SDS-PAGE, but on Western blots of proteins separated by native gradient-PAGE, the antibody recognized a broad band greater than 660 kDa. No effects on fertilizing capacity, embryonic mortality, or hatchability of eggs were observed when the antibody was added to turkey semen prior to insemination. When semen stored for 0, 3, 6, 24, and 48 h was immunolabeled with 4C7/2E4, the percentage of spermatozoa with unlabeled midpieces was significantly increased by 6 h of storage. The number of free mitochondria and damaged midpieces also significantly increased with storage.

Command and control interfaces permit the intention and situation of the user to influence the operation of the neural prosthesis. The wishes of the user are communicated via command interfaces to the neural prosthesis and the situation of the user by feedback control interfaces. Both these interfaces have been reviewed separately and are discussed in light of the current state of the art and projections for the future. It is apparent that as system functional complexity increases, the need for simpler command interfaces will increase. Such systems will demand more information to function effectively in order not to unreasonably increase user attention overhead. This will increase the need for bioelectric and biomechanical signals in a comprehensible form via elegant feedback control interfaces. Implementing such systems will also increase the computational demand on such neural prostheses.

A monoclonal antibody (mAb) to epitopes on mitochondria from turkey spermatozoa cross-reacted with Japanese quail spermatozoal mitochondria. However, the pattern of binding was different from that observed for turkey sperm. The ultrastructure of quail spermatozoa was examined to determine the reason for this difference in antibody binding pattern. Light microscopy, as well as scanning (SEM) and transmission (TEM) electron microscopy, were used to study the morphology of spermatozoa from Japanese quail. Japanese quail had a sauropsid type of sperm cell, which is typical of nonpasserine birds. The spermatozoa were vermiform in shape, with a maximum width of 0.6 microm and an overall length between 230 and 250 microm. An acrosome (3.7 to 4.5 microm), nucleus (20.8 to 23.8 microm), midpiece (160 to 170 microm), and tail (40 to 60 microm) were observed. The TEM showed an acrosomal cap surrounding a perforatorium that inserted into the nucleus at the posterior end. Only a distal centriole was observed, which gave rise to a central axoneme with a 9+2 microtubular structure. The axoneme was encased by a spiraled mitochondrial sheath in the midpiece region (64 to 74% of the overall length of the sperm), and mitochondria numbers were estimated to be greater than 1,400 per sperm. In contrast, turkey sperm contain short midpieces with only 20 to 30 mitochondria per sperm. Differences in binding patterns of the mAb to turkey mitochondria between quail and turkey sperm were due to the presence of mitochondria on the exceptionally long midpieces of quail sperm.

The effects of perfluorochemical (PFC) oxygen carriers in turkey semen diluents on fertility and hatchability was measured for a 10-wk period. Semen was diluted (1:1) with Beltsville Poultry Semen Extender (BPSE) or BPSE:FC-75, an emulsified mixture of BPSE and perfluorobutyltetrahydrofuran (technical grade) (FC-75) and stored for 24 h at 5 C with agitation (150 rpm) and aeration with either air, nitrogen (100%), or oxygen (100%). Sperm concentration and percentage of dead sperm were determined prior to and after storage. Sperm concentration (8.35 to 9.21 x 10(9) per milliliter) was not significantly affected by the type of diluent or aeration gas, and only stored semen diluted with BPSE: FC-75 and aerated with nitrogen had increased percentage of dead sperm. Diluent type did not affect the percentage of fertilized eggs; however, fertility and hatchability for both diluent treatments with nitrogen aeration was significantly lower (P < or = 0.05) than for the semen treatments with air or oxygen aeration. Hatchability for semen diluted with BPSE:FC-75 and aerated with oxygen (63.7%) was significantly higher (P < or = 0.05) than that for BPSE-diluted semen aerated with oxygen (43.2%). Although use of oxygen carrying fluorocarbon emulsified with BPSE did not further improve fertility when the semen was stored for 24 h while oxygenated and mechanically agitated, a beneficial effect was noted for hatchability. The fact that nitrogen severely depressed fertility confirms that the beneficial effects of agitation are due to oxygenation of the spermatozoa. Therefore, further studies of oxygen carriers in semen are warranted.

The semen of turkeys with numerous spermiophages was used for isolating spermiophages by density gradient centrifugation. Isolated spermiophages were suspended in Beltsville Poultry Semen Extender (BPSE) and added to semen with low spermiophage numbers to give approximate spermiophage concentrations of: 2 x 10(5)/mL (medium) and 10(6) (high). Semen with no added spermiophages was the control. Samples were diluted to 1:1 with BPSE, and for each spermiophage level (treatment), semen aliquots were either immediately inseminated or stored 6 h at 4 C with agitation (150 rpm) before insemination. Hens were inseminated weekly, and fertility, embryonic mortality, and hatchability of eggs were determined for a 10-wk period. The experiment was performed twice. In Trial 1, there were no differences in fertility between treatments except that fertility for control stored semen was lower (P < or = 0.05) than that for fresh semen (89.27 vs 95.97, respectively; SEM = 2.2). Neither hatchability nor embryonic mortality was affected by spermiophage level in Trial 1. Spermiophages did not affect fertility in Trial 2; however, hatchability for unstored treatments with added spermiophages was significantly lower than for the control. For stored semen, hatchability was significantly (P < or = 0.05) greater for treatments with added spermiophages than for the control. Differences in embryonic mortality in Trial 2 did not relate to adding spermiophages to the semen. No clearly defined detrimental effect of seminal spermiophages was shown in the present experiments.

In a preliminary study, it was found that aeration of turkey semen diluted 1:2 with a phosphate buffer diluent (PD) and stored for 24 h at 12 to 13 C improved the fertilizing capacity relative to that obtained from PD-diluted semen that was not aerated (63.8 and 14.0%, respectively). Emulsifying PD with an equal volume of the oxygen carrier perfluorobutyltetrahydrofurane (FC-80) and using the resulting emulsion as a diluent further increased the fertility (86.6%), but the best fertility was from unstored, undiluted semen (98.0%). The efficacy of using emulsions of aqueous diluents with FC-80 for 24-h cold storage of turkey semen was studied in detail. When semen diluted with PD:FC-80 emulsions received varying levels of O2 for aeration, the fertilizing capacity of semen aerated with 60 or 100% O2 (86.1 and 89.6%, respectively) was significantly greater (P < or = .05) than that obtained using 20% oxygen (78.5%). The FC-80 emulsions that were made using commercially available diluents in place of the PD were tested with 100% O2 aeration during storage. The percentage fertility obtained from emulsions made with Beltsville Poultry Semen Extender or Lake's 7.1 "mm" Diluent was significantly greater (P < or = .05) than that for PD or Minnesota Turkey Growers Association Extender (90.5 and 90.2% vs 77.6 and 72.6%, respectively). This research demonstrates that perfluorochemicals may be useful for cold storage of turkey semen when emulsified with optimum diluents and aerated with > or = 60% O2.

Three experiments were conducted with lines of chickens selected for high (HA) and low (LA) antibody response to sheep erythrocytes to determine their antibody responses following primary immunization with Brucella abortus. In Experiment 1, HA chicks responded to immunization with a higher total titer than LA chicks at 7 d postimmunization. At both 5 and 7 d following immunization 2-mercaptoethanol-resistant (IgG) titers were higher in HA than LA chicks. There also was a significant sex effect at 7 d in the first experiment, with males having higher total titers than females. In the second experiment, HA chicks had higher total titers at 5 d postimmunization than LA chicks, but IgG titers were similar for both lines. Total and IgG titers of HA chicks used in Experiment 3 were significantly higher than those of LA chicks at 5 and 7 d postimmunization. Both HA and LA chicks exhibited divergent antibody responses to B. abortus although they had originally been selected for antibody responsiveness to sheep erythrocytes.

The chicken Harderian gland (HG) is densely populated in its subepithelial spaces with plasma cells (PC). These immune cells produce and secrete Ig of the IgA, IgG, and IgM classes. Such Ig secretion into the tears affords the upper respiratory tract with protective antibodies. The immunological role of the HG is quite interesting; yet this gland is a site of unusual PC proliferation. Studies of the gland utilizing bromodeoxyuridine (BrdUrd) incorporation into DNA and propidium iodide (PI) staining of PC DNA have verified previous suggestions in the literature that PC of the chicken HG proliferate. Both isolated PC suspensions and frozen sections of the HG from chicks aged 6 to 9 wk reveal that BrdUrd is incorporated into PC DNA. Furthermore, flow cytometric analysis of PI-stained PC indicates a relatively high percentage of PC in S phase of the cell cycle. Continued studies are examining possible mechanisms controlling proliferation and differentiation of PC in the HG. It is believed that the stromal elements of the HG produce and secrete a factor(s) that influences PC proliferation and differentiation. Isolation and characterization of this influencing factor(s) will allow for the possible systemic application of the factor(s) for enhancement of immune responses.

The perfluorochemicals (PFC) have a high capacity for dissolving oxygen and carbon dioxide. Two experiments were conducted using PFC as diluent components to assess their effect on the fertilizing capacity of, and the hatchability of eggs from hens inseminated with, turkey semen stored for 30 min or 3 h. Two PFC were tested for the 30-min experiment: perfluorohexane (FC-72) and perfluorobutyltetrahydrofurane (FC-80). For the 3-h experiment, these PFC plus bis-1,2-(F-butyl)-ethene (F-44E) were studied. The PFC were emulsified with an equal volume of a standard aqueous salt diluent, Beltsville Poultry Semen Extender (BPSE). The BPSE alone was used as a control in both experiments. Semen was diluted 1:2 with oxygen-saturated extender and stored in closed tubes at 20 to 30 C prior to insemination. For the 30-min study, PFC diluents resulted in fertility rates comparable to (FC-72) or significantly greater than (FC-80) BPSE alone (P < or = .05). There was no significant difference in hatchability due to any semen treatment. When semen was stored for 3 h, PFC diluents resulted in comparable (FC-80) or significantly higher (F-44E and FC-72) fertility and hatchability rates. Significantly lower embryonic deaths at Day 10 of incubation were noted for all PFC diluents. These findings provide evidence that PFC emulsions are not toxic and prolong fertilizing capacity of turkey sperm during short-term storage, and suggest that providing oxygen carriers such as PFC in semen diluents may be beneficial.

In the Harderian gland of the chicken, the epithelial and plasma cell relationships were studied by light and electron microscopy and immunohistochemical methods. In the wall of the central canal a dark epithelial cell was identified that had long branching cell processes. An anticytokeratin monoclonal antibody demonstrated that the dark cells provided an extremely large contact area for the plasma cells. Although IgM-, IgG-, and IgA-producing plasma cells were present in the Harderian gland, only IgM- and IgA-positive cells were capable of a distinct relationship with dark epithelial cells. The surface of the primary branches contained scattered IgA deposits whereas the epithelial cells of the secondary branches possessed IgA along the lateral cell membrane but not on the surface. Anti-IgA and anti-cytokeratin antibodies produced a similar staining pattern in the acini and secondary branches. Taken together, these observations suggest that IgA secretion is a function of secondary branches and that intracellular transport is influenced by the cytoskeletal system.

Mitogen responses of peripheral blood lymphocytes (PBL) and the cell cycle analysis of T-cells were examined for lines of chickens selected for high (HA) and low (LA) antibody response to SRBC. At 6 wk of age, within each line, blood samples and thymic tissue were collected from chicks representing the B13B13, B13B21, B21B13, and B21B21 genotypes. Although no influence of Ea-B haplotype on T-cell activity was detected in either line, there were line differences in phytohemagglutin-M (PHA-M) and concanavalin A (Con A) mitogen responses and the percentage G0/G1 and S phase T-cells. The HA PBL had greater in vitro PHA-M and Con A responses, and the cell cycle analysis of T-cells revealed a greater percentage of cells in S phase for Line HA chicks than for LA chicks. There were significantly more resting cells in the G0/G1 phase of LA than HA chicks. Although there was no Ea-B haplotype effect observed on T-cells from either line, generalized selection for high or low antibody response did result in divergent T-cell activity.

Studies were conducted to determine the effects of dietary protein restriction on the humoral immunity (HI) and cell-mediated immunity (CMI) of chickens. New Hampshire chickens were separated into two dietary treatment groups: basal, containing 3,200 kcal/kg and 21% protein; or protein restricted (PR), containing 3,200 kcal/kg and 7% protein. In studies involving HI, half of the birds in each dietary treatment were vaccinated against fowl cholera at 4 and 8 wk of age. Blood samples were collected weekly beginning at 4 wk of age. Overall, unvaccinated birds had lower titers than vaccinated birds and PR groups generally showed lower titers than basal groups. All birds were challenged by palatine cleft inoculation of live, virulent Strain X-73 of Pasteurella multocida. The vaccinated PR group survived live challenge as well as the vaccinated basal group, but all unvaccinated birds died as a result of the challenge, regardless of antibody titer. In studies involving CMI, half of the birds in each dietary treatment were vaccinated at 5 wk of age. At 2 to 3 wk postvaccination, representative birds from each treatment were bled for total and differential blood counts. Also, birds were sacrificed and spleen cells collected. Cells were cultured in Roswell Park Memorial Institute (RPMI) medium with phytohemagglutinin-M (PHA-M), sonicated P. multocida (X-73), or RPMI only.(ABSTRACT TRUNCATED AT 250 WORDS)

A study was conducted to determine the effects of an environmentally induced force molt treatment on concentrations and daily variations of selected serum biochemicals during early molt. Laying hens were placed into two environmental control chambers. In one chamber, control (Con) laying hens were maintained on long photoperiods of 19 hr of light daily to maintain egg production. In the other chamber, early molt (EM) hens were exposed to short photoperiods of 6 hr of light daily to decrease egg production. After 2 weeks in the chambers, feed was withdrawn from EM hens for 2 days to initiate molt. Three days after feed was restored, hens from both groups were blood sampled every 2 hr for 2 days for selected serum biochemical analyses. Serum concentrations of calcium (Ca), inorganic phosphate (P), glutamic pyruvic transaminase (GPT), and albumin (Alb) were depressed in EM hens. Serum concentrations of alkaline phosphatase (Alk P), lactic acid dehydrogenase (LDH), glutamic oxaloacetic transaminase (GOT), glucose (Glu), cholesterol (Chol), and globulin (Glob) were elevated in EM hens. Daily temporal rhythms of Ca, Glu, total protein (TP), and Alb were found in both hen groups. These temporal changes were independent of force molt treatment. Serum GOT was positively correlated with nuclei free liver corticosteroids (LCS) and negatively associated with plasma corticosterone in Con hens. Serum GOT was positively correlated with nuclei free LCS in EM hens.

Chickens from the Lester J. Dreesen strain of New Hampshires and a small (SBL) and a large (LBL) bursa line derived from it were tested with previously prepared reagents for 10 erythrocyte alloantigen systems. Eight systems were shown to be segregating in one or more of the three related lines. Immunogenetic analysis of the hemagglutination reactions resulted in genotype assignments for seven of the systems. The number of alleles segregating at the respective alloantigen loci were three A, five B, three C, two D, two I, two L, and two P. All seven segregating systems displayed considerable divergence in gene frequencies among two or more of the lines. The B1B1 chicks produced significantly higher peak titers against sheep red blood cells than B6B6 chicks; in adults the order of response of genotypes was B1B1, B6B6, B5B5. Peripheral blood leukocytes from groups of adults and 5-wk old chickens responded consistently to phytohemagglutinin-M according to their B genotypes, in the order B1B1, B5B5, B6B6. Serum immunoglobulin G (IgG) concentrations determined at various ages were higher in the LBL than the SBL strain, even after bursectomy. Genes influencing serum IgG levels may be closely linked to one or more of the blood group systems.

Circulating levels of corticosterone were determined in chick embryos from 10 to 21 days of incubation using eggs from a Leghorn breeder flock. In Experiment 1, eggs were incubated from 10 to 20 days for daily embryonic blood collection. To verify stage of development with day of incubation, embryo right middle toe lengths were measured concurrent with blood sampling. Serum from three embryos was pooled into one sample and the corticosterone content of 10 samples per day of incubation was determined using a radioimmunoassay procedure. The levels of corticosterone from day 10 to 14 fluctuated slightly and then increased rapidly until 16 days of incubation. At this time serum corticosterone remained relatively constant through day 18 with an apparent increasing trend up to day 20. The use of toe lengths to assure no day-to-day overlap in embryonic development proved effective. In Experiment 2, newly hatched (day 21) chicks were sorted into four 3-hr periods ranging from early to late hatching. Blood samples were collected from five individual chicks during four 15-min sampling periods for each of the four hatch times. Serum corticosterone levels were not affected by sampling periods or hatch times.

Chicks from a randombred population were assessed for genetic variation in 1-day body weight and serum corticosterone under two brooding temperatures (26.7 and 32.2 C). Brooding at 26.7 C resulted in lower 1-day body weights and higher corticosterone levels. Heritability estimates (h2) for 1-day body weight were moderately high in both temperature groups but were low for gain in both temperatures. The h2 for corticosterone level from chicks brooded at 26.7 C was moderate, whereas estimates for those brooded at 32.2 were very low. Statistically significant (but low) negative phenotypic correlations were obtained for corticosterone with body weight and gain in both temperature groups. A significant negative genotypic correlation was observed between corticosterone and body weight for chicks brooded at 26.7 C but not for those brooded at 32.2 C. Corticosterone data from the highest and lowest responding sire families revealed a significant response group by temperature interaction. Chicks from the first of two additional hatches showed significant response group differences in serum corticosterone to the reduced brooding temperature. The neonatal serum corticosterone response to cold stress has a genetic basis; however, because there was a negative genotypic correlation between serum corticosterone and body weight, selection for increased corticosterone levels under reduced temperature brooding would likely result in decreased body size.

An avian equivalent of the mammalian thyroid isthmus appeared in thiouracil-treated (.1% in feed nd hatching to 6 and 8 weeks of age) chickens. In two experiments in which chickens were fed a diet containing thiouracil, thyroid tissue was found connecting the thyroid glands. Histological examination of the connecting tissue revealed that it was of the same cellular composition as the thyroid glands.

Experiments were conducted to delineate the acute stress response of commercial broilers to feed and water deprivation for 10 hr. The effect of method of nutrient deprivation, cooping versus removal of feed and water from broiler floor pens, was also considered. Bihourly plasma corticosterone measures were made during 10-hr withdrawal periods, and significant alterations in this adrenal steroid were considered indicative of stress. In all studies, feed and water deprivation produced significant elevations in plasma corticosterone concentrations. Cooped broilers exhibited a shorter onset and more exaggerated magnitude of adrenal responsiveness than floor penned broilers deprived of feed and water. There was also evidence that plasma corticosterone secretion in floor penned broilers was continual (linearly increasing) throughout the 10-hr withdrawal period. In contrast, maximal corticosterone responses followed by waning hormonal levels (an increasing quadratic function) were evident in cooped broilers. It was concluded that procedures involved in physically cooping birds, as well as the restraint cooping imposed, were acting additively to the stress associated solely with feed and water deprivation. Changes in plasma volume, as evidenced by percent packed cell volume changes during treatment periods, were not responsible for the corticosterone elevations observed. In a separate experiment, battery housed Japanese quail deprived of feed and water for 12 hr exhibited a temporal plasma corticosterone response very similar to that observed in floor penned broilers deprived of feed and water. Full-fed control quail exhibited only random temporal hormonal fluctuations during this time. It was likewise concluded that the practice of feed and water deprivation in quail constitutes a significant nonspecific stressor.

A pedigreed, randomly mated population of 25 sire families was assessed for genetic variation in body weight, gain, and plasma growth hormone (GH) under conditions of reduced temperature brooding (26.7 C) from day of hatch to 7 days of age. Heritability estimates (h2) for 7-day body weight and gain were moderate to high. The calculated h2 for GH was moderate. Plasma levels of GH were not phenotypically or genotypically correlated with body weight or gain.

An open fracture of the forearm in a patient with osteogenesis imperfecta is reported. Immediate operative debridement and open reduction, combined with rigid external fixation, provided the patient with an excellent functional result.

A series of experiments was conducted to examine the response of neonatal, male broiler chicks to brooding at a reduced temperature. In Trials 1 and 2, chicks brooded at 26.7 C generally had lower body weights and higher serum corticosterone levels during the first week after hatch than those brooded at 32.2 C. However, significant differences in body weight were observed only on Day 6 in Trial 1 and on Days 1 and 5 in Trial 2. Serum corticosterone levels, likewise, were not significantly different on all days in Trials 1 and 2. These hormone levels were statistically different on Days 1 and 5 in Trial 1 and on Days 1 and 3 in Trial 2. Brooding neonates at 26.7 C for 3 days in Trials 3 and 4 resulted in consistently lower body weights and gain and higher serum corticosterone, thyroxine, total protein, albumin, and globulin. Serum growth hormone levels in chicks brooded at 26.7 C were initially depressed the first day but were elevated on the 2 subsequent days, compared with chicks brooded at 32.2 C. Considering the physiological importance of corticosterone and thyroxine in the adaptation of chickens to cold environmental temperatures, it would be useful to evaluate the genetic variation associated with the responsiveness of these hormones in a randombred population and to improve tolerance of neonatal chickens to reduced temperature brooding through selection.

The effects of blood sampling via cardiac puncture in broiler chicks 2 to 4 weeks of age on subsequent body weights were examined in three experiments. No differences were found in chicks bled or stabbed with 18, 22, or 25-gauge needles when compared to chicks not blood sampled. However, male chicks bled at both 2 and 3 weeks of age with a 25-gauge needle demonstrated elevated body weights at 8 weeks of age when compared to chicks not blood sampled.

The effects of three routes of antigen administration, intravenous, intraperitoneal, and intramuscular, were compared in New Hampshire chicks. Chicks were injected with sheep red blood cells (SRBC) or Brucella abortus (BA) at 29 or 34 days of age. Agglutinin response was determined on Days 3, 5, 7, and 12 postimmunization. Route of injection affected total antibody titers to SRBC significantly at all stages of the response. Sex and age effects were not significant. Brucella abortus antibody titers were significantly influenced by age but not by sex and route.