Effects of fiber from tropical corn and forage sorghum silages on intake, digestion, and performance of lactating dairy cows.

Tropical corn silage was compared with sorghum silage as a basal forage in the diets of high producing dairy cows. Sorghum and tropical corn silages were each included in place of ground corn at incremental concentrations in the experimental diets. Eight separate diets were fed, four diets containing each silage ranging in forage neutral detergent fiber (NDF) from approximately 25 to 31% and ranging in total NDF from approximately 41 to 45%. Diets were arranged in a 2 x 4 factorial design and were fed to lactating cows (n = 24; pretrial mean milk production = 39 kg/d; body weight = 656 kg; and days in milk = 81). As concentrations of dietary NDF increased, intake and milk production decreased linearly. The impact of dietary NDF on intake was greater for diets based on tropical corn silage than for diets based on sorghum silage. Energy intake and milk production were reduced, but cows consumed more fiber when challenged with higher dietary concentrations of fiber. The in vitro rate and extent of digestion of dietary samples were correlated with intake response. The rate of in vitro fiber digestion was slower for samples that contained tropical corn silage than for samples that contained sorghum silage. In vivo digestibility measurements were influenced by intake and dietary composition. Results of this trial indicated that sorghum silage can have equal or slightly greater nutritional value than tropical corn silage when these forages are fed at equal concentrations of dietary fiber.

Opioid-mediated responses of dietary protein on reticular motility and plasma insulin.

Four ruminally and abomasally cannulated steers (603 +/- 22.7 kg of body weight) were used to determine whether ruminally undegradable protein (RUP) would exert opioid-mediated effects on reticuloruminal motility or circulating concentrations of insulin. Steers were fed isonitrogenous diets (16% crude protein) containing either 30 or 40% RUP. The low RUP diet was supplemented with urea and soybean meal, and the high RUP diet was supplemented with blood meal, fish meal, corn gluten meal, and meat and bone meal. Diets contained 57% wheat silage and were fed twice daily at 0800 and 1600 h. Experimental periods were 10 d in length. Blood samples were taken from jugular catheters, and reticular motility was measured at hourly intervals on d 10 over a 16-h period. Either naltrexone (0.5 mg/kg of body weight) or saline was infused into the abomasum at the second feeding (9 h). Naltrexone reduced the frequency of reticular contractions by 16.5% for steers fed the low RUP diet. Naltrexone decreased the duration of reticular contractions by 9.3% for steers fed the low RUP diet and increased duration by 8.7% for steers fed the high RUP diet. Naltrexone decreased the opening time of the reticuloomasal orifice, expressed as a percentage of predose measurements, by 16.3% for steers fed the high RUP diet. Insulin was 21.3% higher with the high RUP diet. The postprandial rise in insulin decreased 36.7% with naltrexone. Dietary protein can exert effects mediated by opioids in ruminants.

Screening for hearing loss in juvenile detention centers.

Results of hearing screenings for 226 incarcerated adolescents are presented. Screenings consisted of visual otoscopy check, pure-tone screening, and tympanometry. Failures were defined as excessive cerumen impeding a clear view of the tympanum, failure to respond at 25 dB HL for 1000 through 6000 Hz, or a Jerger Type B or C tympanogram. An overall failure rate of 35.5 percent was found, with 9.8 percent failing otoscopy, 7.5 percent failing tympanometry, and 25.3 percent failing pure-tone screening. Implications for medical and audiologic evaluation in the population are discussed.

Long-term results using ossicular grafts.

Sculpted autologous ossicle and cortical bone grafts were the first materials successfully used to reconstruct the ossicular chain in chronic ear surgery. Over the last 20 years, the use of biocompatible implants has been popularized; as a result, bone grafts have fallen into disfavor with most otologists. To determine if autologous bone grafts remain stable with time, 115 cases in which autologous bone grafts were used between 1971 and 1984 were reviewed. Eighty patients underwent Type III tympanoplasty, stapes arch present. Thirty-five underwent Type IV tympanoplasty, stapes arch absent. Minimum follow-up was 2 years; 30 patients were followed for > or = 10 years. In Type III tympanoplasty, overall the initial air/bone gap was 19.7 dB at 6 months, with 59% of those with improved hearing at 15 dB air/bone gap or better. Hearing remained stable for 10 years with overall hearing of 19.2 dB air/bone gap and 50% with an air/bone gap of < or = 15 dB. In Type IV tympanoplasty, the average air/bone gap was 26 dB at 6 months, with 70% of those having improved hearing with < or = 20 dB air/bone gap. At 10 years, the overall air/bone gap was 29.3 dB, with only 28% maintaining an air/bone gap of < or = 20 dB. Poor eustachian tube function and collapse of the middle ear air space were found to be the primary causes for long-term failure. The initial hearing results using autologous bone are comparable with those achieved with synthetic prosthesis. Hearing results using autologous bone remained stable through 5 years. Beyond 5 years, Type III tympanoplasty remained stable, while there was deterioration in Type IV tympanoplasty due to poor eustachian tube function.

Polymerase chain reaction for bcl-2 in diagnostic lymph node biopsies.

bcl-2 is a marker for the translocation t(14;18)(q32;q21) indicative of follicular B-cell lymphoma. We studied 115 cases of lymphoproliferative disease with the polymerase chain reaction for bcl-2 oncogene using biotin and radiolabeled probes to the major breakpoint and minor cluster regions. Twenty-three percent of B-cell lymphomas were positive for bcl-2. These included 12 of 20 cases of nodular follicular center cell lymphoma (nine small cleaved cell, one mixed small and large cell, and two large cell types). bcl-2 translocation was detected in only three of 45 cases of diffuse B-cell lymphoma, and cases of AIDS-related malignant lymphoma, monocytoid B-cell lymphoma, and mantle zone lymphoma were all negative. Nonneoplastic lymphoid proliferations were negative for bcl-2 including nine cases of abnormal follicular hyperplasia from patients with acquired immunodeficiency syndrome (AIDS) and AIDS-related complex. Cases of T-cell lymphoma and five cases of Hodgkin's disease were also negative. The polymerase chain reaction for bcl-2 is a rapid, sensitive technique in the evaluation of follicular B-cell proliferations, and the use of biotinylated probes and the alkaline phosphatase reaction eliminates the requirement for radioactive reagents.

Neonatal growth delay in alpha-1-antitrypsin disease. Influence of genetic background.

We have developed a transgenic mouse strain, Z#2, which represents a model for alpha 1-protease inhibitor (alpha 1-antitrypsin: alpha 1-Pi)-associated liver disease (Dycaico et al., 1988). Fifteen percent of human infants with alpha 1-Pi disease develop non-viral hepatitis which is sometimes associated with growth retardation. Such hepatitis and growth retardation tend to occur in a subset of families with other alpha 1-Pi affected members who have had non-viral hepatitis. The Z#2 mouse strain exhibits non-viral hepatitis and growth retardation. This phenotype is more pronounced in transgenic offspring of crosses between Z#2 mice and DBA/2J inbred mice, and less pronounced in transgenic offspring of crosses between Z#2 and CBA/J inbred mice. Such phenotypic differences resemble the phenotypic differences seen in human families with alpha 1-Pi-associated liver disease.