大青止泻口服液对雏鸡的亚急性毒性试验

为了确定自拟的大青止泻口服液在雏鸡体内的亚急性毒性作用,分别以大青止泻口服液的2 mL/kg、4mL/kg、6mL/kg体质量剂量给雏鸡灌胃,对照组灌等量生理盐水,连续灌胃14d,观察和测定停药后第1天和第14天各组雏鸡的临床症状、体质量、血常规、血清生化指标,并解剖观察心、肝、脾、肺、肾的变化.结果表明,给药组的以上...     

Detection of Leishmania infantum DNA by real-time PCR in canine oral and conjunctival swabs and comparison with other diagnostic techniques

The use of non invasive sampling, such as collection of conjunctival swabs, as a diagnostic tool for the detection of Leishmania DNA is of interest. The purpose of this study was to evaluate the diagnostic utility of detecting Leishmania infection with the use of conjunctival swab samples in dogs living in a highly endemic area for leishmaniosis and to investigate, for the first time, the presence of Leishmania DNA in oral swabs in the same population. One hundred sixty-three dogs living outdoor and recruited in various provinces of Sicily were studied. Leishmania infantum indirect fluorescent antibody test (IFAT), delayed-type hypersensitivity reaction to leishmanin (DTH) and real-time PCR of blood (BL), lymph node (LN), conjunctival (CS) and oral swab (OS) samples were performed. The positive PCR percentages in LN, CS, OS and BL samples were: 24.5%, 22.1%, 8.7% and 5.5%, respectively. Serological and DTH positive percentages were 27.0% and 73.8%, respectively. Seropositive and LN-PCR positive dogs had a high likelihood to be positive by CS-PCR. The similar positive PCR percentages found in CS and LN samples suggest the use of CS-PCR as non-invasive alternative technique to LN-PCR for the detection of Leishmania infection in dogs. In addition, this study demonstrated, for the first time, the presence of Leishmania DNA in oral swabs in dogs.     

Oral vaccination of chickens against Newcastle disease with I-2 vaccine coated on oiled rice

Antibody response produced by Newcastle disease virus (NDV, strain I-2) when given orally through oiled rice to chickens was determined. Serum samples were collected before and at a weekly interval for 28 days after vaccination and tested for haemagglutination inhibition (HI) antibody to NDV. The results showed 7 days after vaccination HI antibody titre log₂ was 3.8. Moreover, 14 and 28 days after vaccination HI antibody titre log₂ reached 6.5 and 8.0, respectively. All unvaccinated chickens were negative to NDV antibody throughout the study. Significant finding from the present study is that 7 days after vaccination chickens had produced protective antibody against NDV; this is in contrast to previous studies. Therefore, I-2 vaccine coated on the oiled rice is efficacious as it protects chickens from challenge with NDV. Wambura, P. N., 2008. Oral vaccination of chickens against Newcastle disease with I-2 vaccine coated on oiled rice. Tropical Animal Health and Production.     

Improving protective efficacy of BCG vaccination for wildlife against bovine tuberculosis

Possums are a wildlife vector of bovine tuberculosis in New Zealand. Vaccination of possums with BCG is being considered as a measure to control the spread of bovine tuberculosis to cattle and deer. Delivery via oral bait is feasible but BCG is degraded in the stomach. The aim was to determine whether ranitidine (Zantac) would reduce gastric acidity and enhance the efficacy of intragastrically administered BCG. A dose of 75 mg reduced gastric acidity for at least 4 h. Thus, possums were vaccinated intragastrically with BCG after receiving 75 mg ranitidine or ranitidine or BCG alone, as controls, before challenge with virulent Mycobacterium bovis. Proliferative responses of blood lymphocytes to M. bovis antigens after vaccination were significantly higher in possums given ranitidine/BCG compared to controls and seven weeks after challenge they had significantly lower lung weights and spleen bacterial counts than ranitidine alone controls. Vaccination with BCG alone only gave a reduction in loss in body weight. Agents that reduce gastric acidity may be useful in formulating BCG for oral bait delivery to wildlife for vaccination against bovine tuberculosis.     

Why has oral rehydration for calves and children diverged: direct vs. indirect criteria of efficacy

Oral rehydration therapy (ORT) for acute diarrhoea has advanced in contrary directions in humans and animals; the unresolved question is whether this reflects species differences or a divergence in scientific outlook. This review suggests that the explanation lies in the fact that developments in veterinary ORT have the advantage of utilising more reliable criteria than those available from human patients. The dilemma for human ORT is that the validity of systematic reviews and meta-analyses are undermined when the underlying data only reflect crucial variables indirectly and unreliably. It is therefore possible that the approaches currently used to treat calves, which are radically different from those used by paediatricians, could potentially benefit children and the necessary additional research should be initiated. At a time when the value of animal models of human disease is frequently questioned, the benefits of being able to utilise disease models in the target species for clinical research deserve to be emphasised.     

Environmental and lifestyle risk factors for oral squamous cell carcinoma in domestic cats

Oral squamous cell carcinoma (SCC) is a common malignancy in cats, but little currently is known about its etiology. We examined the relationship between risk of oral SCC and factors such as environmental tobacco smoke, flea control products, and diet in 36 domestic cats with histologically confirmed oral SCC and 112 renal disease control cats presented to a large veterinary referral hospital between 1994 and 2000. Questionnaires were mailed to owners of all study and control cats to assess demographic characteristics, lifestyle factors, and level of chemical exposures 2 years before diagnosis. Multivariate relative risks (RR) were used to estimate the relationships between the various factors and the risk of oral SCC. Flea control product use and diet were significantly associated with risk of oral SCC. Cats that wore a flea collar had 5 times the risk of oral SCC as nonusers, after adjustment for other factors (RR = 5.3; P = .002). In contrast, use of flea shampoo substantially reduced risk. Compared to cats eating mostly dry food, those with high canned food intake had a 3-fold increase in risk (RR = 3.6; P = .014); canned tuna fish intake was independently associated with risk (RR = 4.7; P = .004). Exposure to household environmental tobacco smoke was associated with a nonsignificant 2-fold increase in risk (P = .11). Results of this study suggest that flea control products, diet, and perhaps environmental tobacco smoke might be associated with risk of oral SCC and indicate that further investigation into these relationships is warranted.     

Feed intake and oral behaviour of dairy calves housed individually or in groups in warm or cold buildings

The influence of environmental temperature, housing, social company and age on the feed intake and oral behaviours was studied by housing male dairy calves for seven weeks individually (INDIV) or 12 weeks in groups of four; indoors (INGROUP) or outdoors either with (OUTWARM) or without a heated shelter (OUTCOLD). During the milk-feeding period (1–7 experimental weeks), the mean daily milk, hay and total dry matter intakes of INDIV calves were lower than of INGROUP calves (P < 0.05). No differences in the feed intake between OUTWARM, OUTCOLD or INGROUP were found. Nor was found any differences in the feed efficiency (growth kg^− 1 DM) between the treatments. After weaning off milk, during experimental weeks 8 to 11, the total dry matter intake of INGROUP tended to be greater than that of OUTWARM (P = 0.05). There were no other differences in the mean daily feed intakes, nor in the feed efficiency. During the milk-feeding period, INGROUP calves ate more often concentrates (P = 0.05) and ruminated more (P = 0.01) than INDIV calves. During the 12-week experiment, INGROUP calves licked themselves more often than OUTCOLD calves (P = 0.04) and tended to lick more often than OUTWARM calves (P = 0.08). INGROUP calves licked more often penmates or structures and bit more often structures than OUTWARM or OUTCOLD calves (P < 0.05 for all). Overall, with a decreasing temperature, the calves in outside groups spent less time performing oral behaviours. We conclude that group rearing may facilitate calves to start eating and ruminating earlier than individual housing. The effect of low temperatures on the time spent eating solid foods is discussed in relation to housing design.