Chlamydia spp. are obligate intracellular gram-negative bacteria that cause a wide range of significant diseases in humans and animals worldwide, resulting in significant economic losses. Chlamydial infection in cattle has been reported in many countries including China. However, there has been no survey of chlamydial infection of dairy cattle in Guangzhou, southern China. The objective of the present investigation was to examine the chlamydial seroprevalence in dairy cattle in Guangzhou, subtropical southern China by using an indirect hemagglutination assay (IHA). The overall seroprevalence of chlamydial infection in dairy cattle was 7.25% (29/400). Greater than or equal to eight-yr-old dairy cattle had the highest seroprevalence (10.34%), followed by those that were ≥ 6 years old or < 7 years old dairy cattle (10.20%), although there were no statistically significant differences among different groups (P > 0.05). Dairy cattle with 5 pregnancies had the highest seroprevalence (10.81%). These results indicate that chlamydial infection was present in dairy cattle in Guangzhou, subtropical southern China, and integrated strategies and measures should be executed to control and prevent chlamydial infection and disease outbreak in the study region. 相似文献
The peroxisome proliferator-activated receptors (PPARs) are the members of superfamily of nuclear hormone receptors. A great number of studies in rodent and human have shown that PPARs were involved in the lipids metabolism. The goal of the current study was to investigate the expression pattern of PPAR genes in various tissues of chicken. The tissue samples (heart, liver, spleen, lung, kidney, stomach, intestine, brain, breast muscle and adipose) were collected from six Arber Acres broilers (8 weeks old, male and female birds are half and half). Semi-quantitative RT-PCR and Northern blot were used to characterize the expression of PPAR-alpha and PPAR-gamma genes in the above tissues. By semi-quantitative RT-PCR, the results showed the expression level of PPAR-alpha gene was higher in brain, lung, kidney, heart and intestine, medium in stomach, liver and adipose than in spleen, and it did not express in breast muscle. The expression level of PPAR-gamma gene was higher in adipose, medium in brain and kidney than in spleen, heart, lung, stomach and intestine, but it did not express in liver and breast muscle. Northern blot results showed that PPAR-alpha gene expressed in heart, liver, kidney and stomach, and the intensity of hybridization signal was the stronger in liver and kidney than in other tissues, however, PPAR-gamma gene only expressed in adipose and kidney tissues. The results of this study showed the profile of PPAR gene expression in the chicken was similar to that in rodent, human and pig. However the expression profile of chicken also have its own specific trait, i.e. compared with mammals, PPAR-alpha gene can not be detected in skeletal muscle and PPAR-gamma gene can be stronger expressed in kidney tissues. This work will provide some basic data for the PPAR genes expression and lipids metabolism of birds. 相似文献
The advantage of supplemental sodium bicarbonate (NaHCO3) on eggshell quality in laying hens changes with age. Besides increasing calcium (Ca) secretion in the eggshell gland, it may improve Ca absorption in the intestine or kidney.
Hy-Line Brown layers (n = 384), 25 weeks of age, were allocated to two treatment groups in two experiments, each of which included 4 replicates of 24 hens. Hens were fed a basal diet (control) or the basal diet containing 3 g NaHCO3 g/kg for 50 or 20 weeks in Experiment 1 or 2, respectively. A 24-h continuous lighting regimen was used to allow hens to consume the dietary supplements during the period of active eggshell formation.
In Experiment 1, particularly from 25 to 50 weeks of age, and in Experiment 2, NaHCO3 supplementation favoured hen-d egg production at the expense of lower egg weight. The increased eggshell thickness should have nothing to do with the additional eggshell formation, because of the unchanged egg mass and daily eggshell calcification.
At 35 weeks of age in both experiments, NaHCO3 supplementation increased duodenal expression of calbindin-d28k (CaBP-D28k) protein, contributing to higher Ca retention and balance.
From 50 to 75 weeks of age in Experiment 1, the hens had little response to NaHCO3 supplementation and showed a negative trend on eggshell thickness and strength.
It is concluded that dietary supplementation with 3 g NaHCO3 g/kg improves Ca absorption and eggshell quality of laying hens during the peak but not late production period, with the introduction of continuous lighting.
