Neutral detergent-soluble fiber improves gut barrier function in twenty-five-day-old weaned rabbits

The effect of neutral detergent-soluble fiber level on gut barrier function and intestinal microbiota was examined in weaned rabbits. A control diet (AH) containing 103 g of neutral detergent-soluble fiber/ kg of DM included alfalfa hay as main source of fiber. Another diet (B-AP) was formulated by replacing half of the alfalfa hay with a mixture of beet and apple pulp resulting in 131 g of soluble fiber/kg of DM. A third diet (OH) was obtained by substituting half of the alfalfa hay with a mix of oat hulls and a soybean protein concentrate and contained 79 g of soluble fiber/kg of DM. Rabbits weaned at 25 d and slaughtered at 35 d were used to determine ileal digestibility, jejunal morphology, sucrase activity, lamina propria lymphocytes, and intestinal microbiota. Suckling 35-d-old rabbits were used to assess mucosa morphology. Mortality (from weaning to 63 d of age) was also determined. Villous height of the jejunal mucosa increased with soluble fiber (P = 0.001). Rabbits fed with the greatest level of soluble fiber (BA-P diet) showed the highest villous height/ crypt depth ratio (8.14; P = 0.001), sucrase specific activity (8,671 mumol of glucose/g of protein; P = 0.019), and the greatest ileal starch digestibility (96.8%; P = 0.002). The opposite effects were observed in rabbits fed decreased levels of soluble fiber (AH and OH diets; 4.70, 5,848 mumol of glucose/g of protein, as average, respectively). The lowest ileal starch digestibility was detected for animals fed OH diet (93.2%). Suckling rabbits of the same age showed a lower villous height/crypt depth ratio (6.70) compared with the B-AP diet group, but this ratio was higher than the AH or OH diet groups. Lower levels of soluble fiber tended (P = 0.074) to increase the cellular immune response (CD8+ lymphocytes). Diet affected IL-2 production (CD25+, P = 0.029; CD5+CD25+, P = 0.057), with no clear relationship between soluble fiber and IL-2. The intestinal microbiota biodiversity was not affected by diets (P >/= 0.38). Rabbits fed the B-AP and AH diets had a reduced cecal frequency of detection compatible with Campylobacter spp. (20.3 vs. 37.8, P = 0.074), and Clostridium perfringens (4.3 vs. 17.6%, P = 0.047), compared with the OH diet group. Moreover, the mortality rates decreased from 14.4 (OH diet) to 5.1% (B-AP diet) with the increased presence of soluble fiber in the diet. In conclusion, increased levels of dietary soluble fiber improve mucosal integrity and functionality.     

Coxiella burnetii Shedding During the Peripartum Period and Subsequent Fertility in Dairy Cattle

The objective of this study was to assess the effects of Coxiella burnetii shedding or seropositivity on post‐partum recovery and subsequent fertility in high‐producing dairy cows. Given the difficulty in diagnosing C. burnetii infection at the farm level, an exhaustive series of tests in 43 pregnant animals that delivered at least one live calf were conducted, including blood serology and PCR of milk or colostrum, cotyledons (only at parturition), faeces, vaginal fluid against C. burnetii on gestation Day 171–177, at parturition and on Days 1–7, 8–14, 15–21, 22–28, 29–35 and 90–97 post‐partum. During scheduled herd visits, ultrasonography (US) of the genital tract and examination of vaginal fluid were performed on Days 15–21 (V1), 22–28 (V2), 29–35 (V3) and 51–57 (V4) post‐partum by the same veterinarian. Logistic regression analysis revealed that the likelihood of suffering endometritis (the presence of echogenic intrauterine fluid (IUF), cervical diameter of ≥4 cm or endometrial thickness ≥0.75 cm) was lower in C. burnetii‐seropositive animals (OR = 0.10), compared with C. burnetii‐seronegative animals. According to Kaplan–Meier survival analysis, C. burnetii‐seronegative and non‐shedding cows showed a delayed return to luteal activity and conception was delayed in non‐shedding animals, compared with the remaining animals. Overall, the results of our study provide useful insight into the effects of C. burnetii infection on post‐partum recovery and subsequent fertility. In particular, animals not infected with Coxiella seem to be susceptible to infection and not protected against the bacterium in dairy herds. The elevated costs of determining an infection at the farm level, make monitoring of cows virtually impossible from a clinical point of view.     

Factors Affecting the First Service Conception Rate of Cows in Smallholder Dairy Farms in Bangladesh

The successful outcome of an insemination is a combination of both male and female fertility‐linked factors. We investigated the first service conception rate of cows at artificial insemination (AI) in the smallholder dairy farms in Bangladesh. Frozen straws were prepared from ejaculates of Bos indicus (n = 7) and Bos indicus × Bos taurus (n = 7) AI bulls. Fertility was determined from 6101 first services in cows that were performed by 18 technicians in four regions between April 2004 and March 2005. Pregnancy was diagnosed by rectal palpation between 60 and 90 days post‐insemination. The Asian version of Artificial Insemination Database Application (AIDA ASIA) was used for bulls‐, cows‐ and AI‐related data recording, and later retrieved for analysis. The mean ± SD number of inseminations performed from individual bulls and their conception rates were 436.0 ± 21.6 and 50.7 ± 1.9%, respectively. Logistic regression demonstrated body condition scores (BCS), heat detection signs, months of AI and their interactions had greatest effects (odds ratios: 1.24–16.65, p < 0.04–0.001) on first service conception rate in cows. Fertility differed (p < 0.02–0.001) between the regions, previous calving months, months of AI, BCS, parity and heat detection signs of cows. Inseminations based on mounting activity (n = 2352), genital discharge (n = 3263) and restlessness and/or other signs (n = 486) yielded a conception rate of 53.6%, 48.8% and 50.1%, respectively (p < 0.05). Conception rate between technicians ranged between 43.4% and 58.6% (p < 0.05). The days interval from calving to first service (overall mean ± SD = 153.4 ± 80.6) had relationship (p < 0.001) with BCS, months of previous calving and parity of the cows. Fertility at AI in smallholder farms can be improved by training farmers on nutrition and reproductive management of the cows.     

The response of gastrointestinal microbiota to avilamycin, butyrate, and plant extracts in early-weaned pigs

An experiment was designed to evaluate the effects of 3 different additives on the gastrointestinal microbiota of early-weaned pigs. Early-weaned (18 to 22 d; n = 32) pigs (6.0 +/- 0.10 kg of BW) from 8 litters were randomly distributed into 8 pens. Each pen was assigned 1 of 4 dietary treatments: a prestarter or control diet, the control diet with 0.04% avilamycin (AB), with 0.3% sodium butyrate, or with 0.03% plant extract mixture (XT; standardized mixture with 5% (wt/wt) carvacrol extracted from Origanum spp., 3% cinnamaldehyde extracted from Cinnamonum spp., and 2% capsicum oleoresin from Capsicum annum). At the end of the experimental period, 8 pigs per treatment were killed, and samples of their intestinal content were taken. The total bacterial load along the gastrointestinal tract (GIT; stomach, jejunum, cecum, and distal colon) and the lactobacilli and enterobacteria in the jejunum and cecum were measured by quantitative PCR. The total microbial counts along the GIT did not differ among the diets, but there was an increase in the lactobacilli:enterobacteria ratio in the cecum of the piglets on the XT diet (P = 0.003). Restriction fragment length polymorphism of the PCR-amplified V3, V4, and V5 regions of the 16S rDNA gene showed changes in the structure of the microbial community in the jejunum. Dendrograms grouped animals by diets; control with 0.3% sodium butyrate was the treatment that promoted the biggest changes in the microbial ecosystem, followed by AB and then XT. Biodiversity increased when using additives compared with the control diet (P = 0.002). Microbial metabolic activity along the hindgut was studied using the concentration of purine bases and carbohydrase activities. Different patterns for purine bases were observed between diets (diet x intestinal section, P = 0.01). The control diet reached a maximum purine base concentration at the end of the colon, whereas that of the AB diet was reached at the cecum. We could not detect any cellulase or xylanase activities in animals of this age. Appreciable amylase and amylopectinase activities were found, but they did not differ between diets. The results suggest that the effects of avilamycin, butyrate, or the plant extract would not be related to a reduction in the number of total bacteria inhabiting different sections of the GIT but rather to changes in the ecological structure and metabolic activity of the microbial community.     

Nasal immunization with inhibin DNA vaccine delivered by attenuated Salmonella choleraesuis for improving ovarian responses and fertility in cross‐bred buffaloes

This study was conducted to determine the effect of immunization with inhibin DNA vaccine delivered by attenuated Salmonella choleraesuis on ovarian responses and fertility in cross‐bred buffaloes. A total of 134 cross‐bred buffaloes were divided into four groups: groups T1 (n = 34), T2 (n = 35) and T3 (n = 31) were nasal immunized twice a day with 10 ml of 1 × 10¹⁰ CFU/ml of the C501 (pVAX‐asd‐IS) vaccine for 5, 3 and 1 day, respectively. Group C (n = 34) was nasal immunized with 10 ml PBS for 5 days. All animals were immunized twice with an interval of 14 days and administered with 200 μg of a GnRH analogue on day 28, 0.5 mg PGF_2α on day 35 and 200 μg of the same GnRH analogue on day 37. TAI was performed at 18 and 24 hr after the second GnRH treatment. Fourteen days after primary immunization, C501 (pVAX‐asd‐IS) elicited significant immune responses, and anti‐inhibin IgG antibody titres in group T1 were significantly higher (p < .01) than groups T3 and C. After the second GnRH treatment, the growth speed of the dominant follicles in group T1 was significantly faster (p < .05) than groups T3 and C. The number and diameter of large follicles (≥10 mm) as well as ovulatory follicles in group T1 were the greatest in all groups, resulting in a greater conception rate in buffaloes with positive anti‐inhibin antibodies. These results demonstrate that immunization with the C501 (pVAX‐asd‐IS) vaccine, coupled with the Ovsynch protocol, could be used as an alternative approach to improve reproductive performance in cross‐bred buffaloes.     

Bragg diffraction from crystallized ion plasmas

Single crystals of a one-component plasma were observed by optical Bragg diffraction. The plasmas contained 10(5) to 10(6) single-positive beryllium-9 ions (9Be+) at particle densities of 10(8) to 10(9) per cubic centimeter. In approximately spherical plasmas, single body-centered cubic (bcc) crystals or, in some cases, two or more bcc crystals having fixed orientations with respect to each other were observed. In some oblate plasmas, a mixture of bcc and face-centered cubic ordering was seen. Knowledge of the properties of one-component plasma crystals is required for models of white dwarfs and neutron stars, which are believed to contain matter in that form.     

Hydrogen radicals, nitrogen radicals, and the production of O3 in the upper troposphere

The concentrations of the hydrogen radicals OH and HO2 in the middle and upper troposphere were measured simultaneously with those of NO, O3, CO, H2O, CH4, non-methane hydrocarbons, and with the ultraviolet and visible radiation field. The data allow a direct examination of the processes that produce O3 in this region of the atmosphere. Comparison of the measured concentrations of OH and HO2 with calculations based on their production from water vapor, ozone, and methane demonstrate that these sources are insufficient to explain the observed radical concentrations in the upper troposphere. The photolysis of carbonyl and peroxide compounds transported to this region from the lower troposphere may provide the source of HOx required to sustain the measured abundances of these radical species. The mechanism by which NO affects the production of O3 is also illustrated by the measurements. In the upper tropospheric air masses sampled, the production rate for ozone (determined from the measured concentrations of HO2 and NO) is calculated to be about 1 part per billion by volume each day. This production rate is faster than previously thought and implies that anthropogenic activities that add NO to the upper troposphere, such as biomass burning and aviation, will lead to production of more O3 than expected.     

Atmospheric residence time of CH3Br estimated from the junge spatial variability relation

The atmospheric residence time for methyl bromide (CH3Br) has been estimated as 0.8 +/- 0.1 years from its empirical spatial variability relative to C2H6, C2Cl4, CHCl3, and CH3Cl. This evaluation of the atmospheric residence time, based on Junge's 1963 general proposal, provides an estimate for CH3Br that is independent of source and sink estimates. Methyl bromide from combined natural and anthropogenic sources furnishes about half of the bromine that enters the stratosphere, where it plays an important role in ozone destruction. This residence time is consistent with the 0.7-year value recently calculated for CH3Br from the combined strength estimates for its known significant sinks.     

Comparison of the Johne''s absorbed EIA and the complement-fixation test for the diagnosis of Johne''s disease in cattle

A commercially available absorbed ELISA for the diagnosis of Johne's disease (JD) (paratuberculosis) in cattle, the Johne's Absorbed EIA, was compared with the conventional complement-fixation test (CFT) used in Australia. Stored plasma from 3 Victorian dairy herds with a history of JD, sera from specimens submitted from animals showing clinical signs of JD and sera from the US National Repository for Paratuberculosis Specimens were used to determine the sensitivity of each test. The EIA detected 48.8% of 43 Australian animals with subclinical JD, while the CFT detected only 12 (21.4%) of 56 subclinically affected cattle. Of 150 subclinically infected US cattle, the EIA detected 47.3% and the CFT detected 52.0%. The EIA detected 59.7% of animals which at the time of sampling were shedding Mycobacterium paratuberculosis in their faeces, but showed no clinical signs of JD, while the CFT detected 57.3%. The EIA correctly identified 88.2% of 136 histologically confirmed clinical cases, and the CFT detected 83.4%. The specificity of each test was determined by testing sera collected at slaughter from animals residing in a known JD-free area of Australia, and from samples from the US National Repository of Paratuberculosis Specimens collected from certified-free herds in Wisconsin. The EIA was found to have a specificity of 99.8% when 998 Australian animals were used as the test population, and 99.0% when 196 US animals were used. The specificity of the CFT using Australian samples was 96.9% and 95.2% using American samples.