Periodic vicissitudes of different concentrations of a developed prototype killed S. aureus mastitis vaccine on immune modulators,mediators and immunoglobulins in cows

Tropical Animal Health and Production - Mastitis is the inflammation of the mammary gland due to microbial infiltration causing a reduced mammary function. This study aims at developing a vaccine...     

Responses of testosterone hormone concentration,semen quality,and its related pro-inflammatory cytokines in bucks following Corynebacterium pseudotuberculosis and its mycolic acid infection

Tropical Animal Health and Production - Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis, a debilitating chronic disease of sheep and goats. Little is known about...     

Serological survey for <Emphasis Type="Italic">Brucella</Emphasis> antibodies in donkeys of north-eastern Nigeria

A cross-sectional epidemiological study was conducted to determine seroprevalence and risk factors influencing the presence of Brucella antibodies in donkeys of Borno State, north-eastern Nigeria. The study aimed at providing baseline information that may be used in planning a control policy against equine brucellosis. Blood samples were collected from 601 donkeys, comprised of 374 males and 227 females from the six agricultural zones of the state between March 2013 and September 2014. The sera obtained were tested for Brucella antibodies using Rose Bengal plate test (RBPT) and competitive enzyme-linked immunosorbent assay (cELISA). Of the 601 donkeys tested, 43 (7.2%) and 40 (6.7%) were seropositive by RBPT and cELISA, respectively. A seroprevalence of 8.6% was obtained in male and 3.5% in female donkeys. According to age, the highest seroprevalence of 9.6% was obtained from donkeys of age group 4–6 years. With respect to pregnancy status, a higher seroprevalence (6.8%) was obtained from pregnant donkeys compared to 3.8% obtained from the non-pregnant ones. There were statistically significant associations between the presence of antibodies and sex (p < 0.05) and the presence of antibodies and age (p < 0.05) of the studied donkeys. However, no statistically significant association (p > 0.05) was observed between the pregnancy status and presence of antibodies. The study concludes that Brucella infection is present in donkeys in all the agricultural zones of the state. The relatively high seroprevalence (7.2%) obtained is of public health concern because of the close interaction between donkeys, ruminants, and humans in the study area.     

Nitrogen fixing activity in warty lenticellate tree barks

Detached lenticellate warty bark of Inga laurina was first shown to develop acetylene reducing activity (ARA) (18 nmol C₂H₂red·g^-1 (F.W.)·hr^-1) after a few days' incubation with ambient air containing 0.10 atm C₂H₂. Similar N₂ase development was found to occur with warty barks of many other plant species including 12 leguminous and 9 non-leguminous trees growing in wet tropical and temperate forests. Among them higher activities (>7 nmol C₂H₂ red·g^-1 (F.W.)·hr^-1) were recorded in Inga laurina, Cynometra ramiflora, Cassia siamea, Robinia pseudo-acacia, Albizia julibrissin in the leguminous plants, and Ilex crenata, Ilex pedunculosa, Rhizophora mucronata, Bruguiera gymnorrhiza and Mallotus japonicus in the non-leguminous plants. The development of ARA was often accelerated under lower pO₂ (0.05 atm) and pC₂H₂ (0.05 atm). Complete replacement of O₂ with N₂ or Ar in the incubation atmosphere resulted in full suppression of the development of N₂ase activity.

When ARA measurement was made with intact barks of natural stands (Robinia pseudo-acacia, Ilex pedunculosa and Mallotus japonicus), it was found that all of these intact barks were reducing C₂H₂ linearly without any time lag. The activities recorded were 4.6–11.5 nmol C₂H₂ red·g^-1 (F.W.)·hr^-1 corresponding to 1.19–1.27 nmol C₂H₂ red·cm^-2hr^-1. These values roughly coincided with ARA of detached warty barks of the same plant species. The present results suggest that in situ N₂-fixation in tree barks of the forests would amount to several 10 kg·ha^-1·year^-1 in temperate and tropical wet forests