Microvasculature of the buffalo epididymis

The microvasculature of the water buffalo (Bubalus bubalis) epididymis was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo epididymis showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in the caput, corpus, and cauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo epididymis plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were many diverticula. These diverticula appear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo epididymis, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium. Anat Rec 266:58–68, 2002. © 2002 Wiley‐Liss, Inc.     

Sperm binding to hyaluronan is an excellent predictor of Nili-Ravi buffalo bull fertility

This study reports the first evaluation of sperm hyaluronan binding assay (HBA) for predicting the fertility of Nili-Ravi buffalo bulls in relation to standard parameters of sperm quality. Cryopreserved semen doses of low (n = 6), medium (n = 3) and high fertility (n = 8) bulls based on their respective return rates were used. Significantly, more spermatozoa bound to hyaluronan from the most fertile bulls (57.15% ± 1.44) compared with medium (42.46% ± 1.08) and low fertility bulls (29.70% ± 0.78). A strongly positive correlation (r = .824, p < .01) was found between HBA and fertility that predicts a 67.9% variability (r² = .679, p < .01) in fertility. HBA was also strongly positively correlated with sperm viability (r = .679, p < .01) followed by their live/dead ratio (r = .637, p < .01), uncapacitated spermatozoa (r = .631, p < .01), normal apical ridge (r = .459, p < .01), motility (r = .434, p < .01), mature spermatozoa with low residual histones (r = .364, p < .01), high plasma membrane integrity (r = .316, p < .01) and nonfragmented DNA levels (r = .236, p < .05). It was negatively correlated with spermatozoa having reacted acrosome (r = −.654, p < .01). A fertility model built using a combination of sperm HBA and either sperm livability or viability predicts, respectively, 86.1% (r² = .861, p < .01) and 85.9% (r² = .859, p < .01) variability in buffalo bull fertility. In conclusion, sperm HBA may prove to be a single robust predictor of Nili-Ravi buffalo bull fertility.     

重组日本血吸虫26 kDa GST抗原免疫水牛后抗体动态及免疫保护性效果

目的　观察重组日本血吸虫 2 6kDaGST抗原 (reSjc2 6GST)免疫役用放养水牛 (简称水牛 )后抗体动态及免疫保护性的效果。　方法　试验组 96头水牛 ,用reSjc2 6GST免疫 3次 ,每次间隔 2wk ,3次剂量分别为 0 2、 0 2和 0 1mg。对照组 90头水牛不作免疫 ;观察 2组水牛免疫前及免疫后 2、 5、 9、 12、 15和 2 0个月的抗体水平及血吸虫感染率的变化。　结果　试验组机体产生特异性抗reSjc2 6GST抗体 ,其抗体水平呈明显的梯形升高趋势。试验组免疫后 2 0个月血吸虫感染率比免疫前下降了 62 2 % ,比同期对照组低 67 7%。　结论　用reSjc2 6GST免疫水牛能产生特异性抗体 ,在免疫后 2 0个月内维持较高水平 ,有一定的抗血吸虫自然感染的保护力。     

Natural resistance to worms exacerbates bovine tuberculosis severity independently of worm coinfection

Pathogen interactions arising during coinfection can exacerbate disease severity, for example when the immune response mounted against one pathogen negatively affects defense of another. It is also possible that host immune responses to a pathogen, shaped by historical evolutionary interactions between host and pathogen, may modify host immune defenses in ways that have repercussions for other pathogens. In this case, negative interactions between two pathogens could emerge even in the absence of concurrent infection. Parasitic worms and tuberculosis (TB) are involved in one of the most geographically extensive of pathogen interactions, and during coinfection worms can exacerbate TB disease outcomes. Here, we show that in a wild mammal natural resistance to worms affects bovine tuberculosis (BTB) severity independently of active worm infection. We found that worm-resistant individuals were more likely to die of BTB than were nonresistant individuals, and their disease progressed more quickly. Anthelmintic treatment moderated, but did not eliminate, the resistance effect, and the effects of resistance and treatment were opposite and additive, with untreated, resistant individuals experiencing the highest mortality. Furthermore, resistance and anthelmintic treatment had nonoverlapping effects on BTB pathology. The effects of resistance manifested in the lungs (the primary site of BTB infection), while the effects of treatment manifested almost entirely in the lymph nodes (the site of disseminated disease), suggesting that resistance and active worm infection affect BTB progression via distinct mechanisms. Our findings reveal that interactions between pathogens can occur as a consequence of processes arising on very different timescales.

Interactions between pathogens cooccurring within a single host can have profound effects on infection outcomes, ranging from the severity of clinical disease in individual hosts to the rate of disease spread across populations (1–3). Because most hosts are commonly infected by more than one type of pathogen at a time (4), understanding the consequences of pathogen interactions during concurrent infection (or coinfection) is essential for effective disease management and control. While many studies focus on pathogen interactions that are the result of one pathogen responding to the simultaneous presence of another (5), two pathogens need not overlap in time to interact with one another. For example, heterologous immunity, where prior exposure or infection with one pathogen modifies the immune response to another, can drive both positive and negative interactions between pathogens (6). This phenomenon highlights how modifications of the host immune system by one pathogen that occur during the lifetime of a host (i.e., in ecological time) can shape future responses to secondary pathogens. Likewise, strong selection pressure imposed by pathogens on hosts, particularly on immune function (7), can result in modifications of the host immune system that occur over generations (i.e., in evolutionary time), a process which should also affect responses to secondary infections. In this case, a historical population-level response to selection by one pathogen may generate heritable differences among individuals in contemporary responses to another. Crucially, ecological- vs. evolutionary-scale interactions between pathogens may operate for different reasons, so distinguishing between the two is integral to understanding both the mechanistic basis and consequences of these interactions.Helminths, or parasitic worms, and tuberculosis (TB) are involved in one of the most geographically extensive of pathogen interactions (2, 8). Both pathogens affect approximately one-third of the world’s human population and are widespread in domestic and wild animals (9–11). Caused by bacteria in the Mycobacterium tuberculosis complex, including M. tuberculosis (Mtb), the causative agent of human TB, and Mycobacterium bovis (Mb), the causative agent of bovine TB, TB is responsible for 2 million human deaths (12) and 25% of all disease-related cattle deaths (13) annually. In humans, about 10% of individuals infected with Mtb progress to active pulmonary disease, but the mechanisms underlying progression to active TB are poorly defined (14). Accumulating evidence suggests that coinfection with worms may be a factor in TB disease progression (2, 15), although some studies do not support this link, highlighting the complex nature of worm–TB interactions (16). Interestingly, research in laboratory animals suggests that enhanced immunity (i.e., resistance) to worms can compromise a host’s ability to control TB even in the absence of active worm infection (17–20), implying that evolved defenses against worms may independently affect the response to TB. Considered in light of widespread worm resistance in human and animal populations (21, 22) and the broad geographic coincidence of worms and TB, worm–TB interactions may represent an illustrative case where variation in evolved resistance to one pathogen (worms) contributes to variable responses to another (TB).In this study, we tested the hypothesis that resistance to worms modifies the host response to TB. To do this, we monitored gastrointestinal (GI) worm (specifically strongyle nematode) and Mb infections in a cohort of wild African buffalo (Syncerus caffer) to assess the effects of natural variation in worm resistance on the incidence, severity, and progression of bovine TB (BTB). In previous work, we demonstrated the presence of an ecological interaction between worms and BTB in buffalo by showing that clearance of active worm infection via anthelmintic treatment reduces BTB-associated mortality (23). Thus, we took advantage of the fact that half of our study animals were subject to long-term deworming to compare the relative effects of worm coinfection vs. natural worm resistance on BTB outcomes. We found evidence of a genetic basis to worm resistance in buffalo and that buffalo with resistance to worms were more severely affected by BTB in terms of both mortality risk and disease progression. However, the mechanisms by which natural variation in the host response to worms was associated with BTB progression appeared to be distinct from the effects of anthelmintic treatment. Our results suggest that negative effects of worms on BTB outcomes occur as a result of both concurrent worm infection and genetically based differences in host responsiveness to worms. This discovery fundamentally alters our understanding of the timescales over which worms and TB interact in real-world populations.     

The Socioeconomic Impacts of Clinically Diagnosed Haemorrhagic Septicaemia on Smallholder Large Ruminant Farmers in Cambodia

Haemorrhagic septicaemia (HS) is an acute fatal infectious disease of mainly cattle and buffalo and outbreaks occur commonly in Cambodia. Disease outbreak reports were examined to select five villages from three provinces for a retrospective investigation of HS epidemiology and socioeconomic impact on smallholders, with an aim of identifying potential benefits from improving disease prevention through biosecurity and vaccination. The Village Animal Health Worker (VAHW) or Chief in each village and 66 affected smallholders were surveyed. At the village level, 24% of all households were affected with an estimated mean village herd morbidity of 10.1% and mortality of 28.8%. Affected farmers reported HS disease morbidity and mortality at 42.7% and 63.6% respectively. Buffalo had a higher morbidity (OR = 2.3; P = 0.003) and mortality (OR = 6.9; P < 0.001) compared with cattle, and unvaccinated large ruminants a higher morbidity (OR = 2.9; P = 0.001). The financial impact varied depending on whether the animal survived, provision of treatment, draught replacement and lost secondary income. The mean cost per affected household was USD 952.50 based on ownership of five large ruminants. The impact per affected animal was USD 375.00, reducing the pre‐disease value by 66.1%. A partial budget revealed an overwhelming incentive for farmers to practice biannual vaccination, with a net benefit of USD 951.58 per household based on an annual disease incidence rate of 1. Sensitivity analysis showed that a net benefit of USD 32.42 remained based on an outbreak every 20 years. This study indicates HS can cause a catastrophic financial shock to smallholders and remains a critical constraint to improving large ruminant productivity and profitability. Addressing HS disease control requires a focus on improving smallholder farmer knowledge of biosecurity and vaccination and should be priority to stakeholders interested in addressing regional food insecurity and poverty reduction.     

Detection of Bovine Papilloma Viruses in Wart‐Like Lesions of Upper Gastrointestinal Tract of Cattle and Buffaloes

In present investigation, etiopathological characterization of upper gastrointestinal tract (GIT) tumours of cattle and buffaloes was undertaken. A total of 27 GIT wart‐like lesions in rumen, reticulum, mouth and oesophagus of cattle and buffaloes revealed the presence of small nodular to larger spherical or slender growths with thin base present on mucosa and ruminal pillar. Histopathologically, these cases were diagnosed as fibropapilloma/papilloma. This is the first world record on ruminal papillomatosis in buffaloes. Ruminal warts of cattle and buffaloes revealed the presence of BPV‐5, ‐1 & ‐2, which is the first report of presence of these BPVs in the ruminal warts from India. Quantitative real‐time PCR revealed that DNA samples of different GIT wart‐like lesions contained varying amount of BPV DNA copy numbers. Immunohistochemistry revealed that the PCNA and Ki67 immunopositivity was present in the basal and spinosum layer of the fibropapilloma/papilloma, indicating these as the cellular proliferation site. In conclusion, the present investigation revealed that BPV‐5, ‐1 & ‐2 are associated with certain ruminal wart‐like lesions/growths in cattle and buffaloes, and the basal and spinosum layer of the ruminal fibropapilloma/papilloma were cellular proliferation sites.     

Cervical lipomatosis in HIV-infected patients: a case-control study

OBJECTIVES: The aim of the study was to analyse the prevalence of cervical lipomatosis (CL) in HIV-infected patients on highly active antiretroviral therapy (HAART) and the factors associated with its development. METHODS: This was a multicentre, observational, 1:1 case-control study. HIV-infected patients with CL (cases) and HIV-infected patients from the same cohort, controlled for age (+/-5 years), sex and body mass index (+/-2.5 kg/m(2)) (controls), were included in the study, and a multiple conditional logistic regression was performed to identify factors related to CL. RESULTS: CL was reported in 80 patients (1.8%) from a cohort of 4214 patients on HAART followed up in 10 Spanish hospitals. CL was associated with time of exposure to stavudine [for each 6-month increase, odds ratio (OR) 5.82, 95% confidence interval (CI) 5.70-5.94, P=0.0073] and lipoatrophy (OR 8.04, 95% CI 2.93-22.02, P=0.00001). CONCLUSIONS: Although lipodystrophy is very frequent among HIV-infected patients on HAART, CL is an uncommon type of fat redistribution in this population, and in our cohort it was related to time of exposure to stavudine and lipoatrophy.     

Occurrence of aflatoxin M1 in raw milk of five dairy species in Ahvaz,Iran

During November 2007 to December 2008, 311 samples of raw milk from cow, water buffalo, camel, sheep, and goat were collected in the Ahvaz (southwest Iran). All of the samples were analyzed for presence of aflatoxin M1 (AFM1) by competitive ELISA technique. AFM1 was found in 42.1% of the samples by average concentration of 43.3 ± 43.8 ng/kg. The incidence rates of AFM1 in raw cow, water buffalo, camel, sheep, and goat milks were, 78.7%, 38.7%, 12.5%, 37.3%, and 27.1%, respectively. The concentration of AFM1 in all of the samples were lower than Iranian national standard and FDA limit (500 ng/l), but in 36% of raw cow milk, 8% water buffalo milk, 3.9% sheep milk, and 5.7% raw goat milk samples were higher than maximum tolerance limit accepted by European union/Codex Alimentarius Commission (50 ng/l). The results showed that the milk of camel, goat, and sheep is safe respect to AFM1 contamination in this area.     

Molecular cloning and expression of the dihydrofolate reductase (DHFR) gene from adult buffalo fly (Haematobia irritans exigua): effects of antifolates

The folate analogues methotrexate, aminopterin and pyrimethamine were toxic when fed in a blood meal to adult buffalo flies (Haematobia irritans exigua), but aminopterin caused greater mortality than methotrexate, while trimethoprim was not toxic to adult flies. This is the first recorded instance of mortality in adult insects caused by ingestion of folate analogues. In order to investigate the mechanism of this toxicity, the dihydrofolate reductase (DHFR) gene was cloned from adult buffalo fly cDNA using a PCR-based approach. The full-length DHFR coding sequence (BF-DHFR) was 887 bp and contained an open reading frame encoding a protein of 188 amino acids. The deduced protein sequence identities between BF-DHFR and the other known insect DHFR sequences were: Drosophila melanogaster, 75%; Aedes albopictus, 54%; Heliothis virescens, 43%. The BF-DHFR gene has a single 52 bp intron, an organization more similar to Dipteran species (Drosophila and Aedes). The cDNA encoding BF-DHFR was inserted into an Escherichia coli expression vector and the recombinant protein was expressed to levels representing about 25% of total cell protein. The active enzyme was purified by affinity chromatography on methotrexate-agarose and displayed a relatively low affinity (IC50 = 30 nm) for methotrexate.