Prevalence and risk factors associated with Tritrichomonas foetus infection in cattle in the state of Paraíba, Brazil
The objective of this study was to determine the prevalence of Tritrichomonas foetus infection and to evaluate risk factors associated with this infection among cattle in the state of Paraiba in northeastern Brazil. Samples of cervicovaginal mucus from 290 females and smegma from 59 males [beef, 31; mixed aptitude (beef and dairy), 10; and dairy, 18] from 31 farms were collected. Modified Diamond’s medium and polymerase chain reaction (PCR) were used for the laboratory diagnosis of T. foetus infection. Univariate analysis and logistic regression were performed to test for potential risk factors in addition to prevalence mapping. No sample was positive for T. foetus in culture, and the prevalence of T. foetus infection using PCR was 3.7% (13/349) [confidence interval (CI) 95%, 2.1%–6.4%]. In total, 19.3% (6/31) of the farms had at least one animal positive for T. foetus. The contact of females with males from other farms [Odds ratio, 5.9; 95% CI, 1.5–22.4; p = 0.009] was identified as a risk factor for T. foetus infection. This study demonstrates that T. foetus infection is prevalent among dairy cows in the state of Paraiba, Brazil. Sexual resting, removal of positive females, and avoiding contact of females with males from other farms are recommended to reduce the risk of infection.
Prevalence and risk factors associated with bovine genital campylobacteriosis and bovine trichomonosis in the state of Pernambuco, Brazil
The aim of the present study was to determine the prevalence and risk factors associated with Campylobacter fetus subsp. venerealis and Tritrichomonas foetus infection in cows from dairy herds in the state of Pernambuco, Brazil. In total, 383 samples of cervico-vaginal mucus were collected from cows on 21 herds in 19 districts. Genomic DNA was extracted from the samples and submitted for polymerase chain reaction analysis. An investigative questionnaire was used to analyze the risk factors, using questions related to reproductive and hygiene/sanitation management. A prevalence of 1.8 % (0.8–3.9 %; confidence interval (CI) 95 %) and 33.4 % (28.7–38.4 %; CI 95 %) was found for C. fetus subsp. venerealis and T. foetus, respectively. In terms of the number of foci, 28.6 % of the herds contained at least one animal that was positive for C. fetus subsp. venerealis and 90.5 % for T. foetus. The present study identified herds larger than 100 animals as a risk factor for bovine genital campylobacteriosis (OR = 7.2; CI 1.3–38.4 %; p = 0.020) and the use of natural breeding as a risk factor for bovine trichomonosis (OR = 2.4; CI 1.1–5.9 %; p = 0.041). In conclusion, C. fetus subsp. venerealis and T. foetus infections occurred in the region studied and high numbers of foci were found. Thus, prophylaxis and control measures, such as diagnosis, separation, and sexual rest for infected females, are suggested. An artificial insemination program with early rigorous sanitary care should be implemented on the properties in order to avoid the spread of agents in the herds.
Comparative studies of α-Lactalbumin and lysozyme: Echidna lysozyme
Summaryα-Lactalbumin is a modifier protein for galactosyl transferase in the biosynthesis of lactose and lysozyme catalyses the cleavage of β(1–4) glycosidic linkages. It is now generally believed that α-lactalbumin and lysozyme have diverged from a common ancestor. Comparative studies of these proteins from several species are reported here.The presence of lactose and lactose synthetase activity is shown in mature milk samples from a variety of placental mammals (eutheria) and a pouch bearing mammal (marsupialia). The isolation of the α-lactalbumins involved and their properties are compared.The position is different in the milk samples of monotremes. The α-lactalbumin, lactose and lactose synthetase activity levels in the two platypus samples studied are very low. The levels of lactose and lactose synthetase activity in some echidna(Tachyglossus aculeatus) samples are low, but appreciable in others. No α-lactalbumin is present. The lysozyme activity is appreciable, some samples containing a different lysozyme from that present in others. One of these (designated echidna lysozyme I) is capable of lactose synthetase modifier activity in the presence of bovine “A protein”.The properties of this lysozyme are compared with those of lysozymes and α-lactalbumins from a variety of species and their significance is discussed.