PrP genotype and lamb birth weight in a scrapie-free environment: Is there an association?

The National Scrapie Plan (NSP) for Great Britain includes selective breeding programmes. These aim to reduce the frequencies of the ovine prion protein (PrP) genotypes at high risk of developing clinical disease (principally those containing the VRQ allele) within the national flock, and select for the low-risk ARR-containing genotypes. The aim of this work was to use available data from embryo transfer programmes in guaranteed scrapie-free environments to investigate whether there was a difference in lamb birth weight associated with the lamb's PrP genotype, which might affect survival. The first analysis utilised data from 355 Cheviot lambs born between 2001 and 2004. The analysis was then repeated using a larger data set of 737 Cheviot, Dorset and Suffolk lambs born between 1999 and 2003. The most important determinants of mean lamb birth weight were litter size, sex and recipient ewe breed, plus lamb breed in the three breed analysis. In both analyses the effects of all these variables are consistent and of the same order of magnitude. In the first analysis there was evidence for an apparent increase in mean lamb birth weight for the ARR-containing genotypes of 0.3 kg (95% C.I. 0.1–0.5 kg). Whereas, in the second data set there was evidence for a decrease in mean lamb birth weight for the VRQ-containing genotypes of − 0.6 kg (95% C.I. − 0.8 to − 0.4 kg). This had been masked in the first analysis by the categorisation of these genotypes with the ARQ/ARQ genotype. Within these flocks, in a scrapie-free environment, neither finding provides support for concerns that selection for low risk ARR-containing genotypes would be detrimental to lamb birth weight, which is considered to be the most important determinant of lamb survival. Extension of this work into field flocks, where scrapie-status cannot be easily assured, will require the collection of sufficient data to adjust for known direct effects as well as any additional potential confounding effects.     

Evaluation of foot and mouth vaccination for yak (<Emphasis Type="Italic">Bos grunniens</Emphasis>) in Pakistan

In northern Pakistan, many farming communities rely on domestic yak (Bos grunniens) as a principle source of income. A 2006 participatory disease surveillance report from this region indicated that foot-and-mouth disease (FMD) is the most prevalent annual disease of yak. Our objectives of this study were to determine exposure levels of yak to FMD virus; implement a vaccination program based on current, regional FMD virus serotypes and subtypes; and quantify immune responses following vaccination. Blood samples were used to determine pre-vaccination exposure of animals to FMD virus by antibody presence to non-structural proteins of FMD virus using a 3-ABC trapping indirect ELISA. Vaccine used consisted of FMD serotypes ‘O’ (PanAsia-2), ‘A’ (Iran-05), and ‘Asia-1’ (Shamir), but changed later during the study to match newly circulating viruses in the country (‘O’-PanAsia-2; ‘A’-Turk-06 and Asia-1-Sindh-08). Three hundred sixty-three blood samples were tested from selected villages to determine pre-vaccination FMD virus exposure in yak with an average of 37.7%. Immune responses from initial vaccination and booster dose 30 days later showed clear protective levels (as mean percent inhibition) of antibodies against structural proteins of serotypes ‘O,’ ‘A,’ and ‘Asia-1.’ These responses remained above threshold positive level even at day 210 following initial vaccination. Results of sero-surveillance and anecdotal information of repeated FMD outbreaks demonstrate the persistence of FMD virus of yak in northern Pakistan. Laboratory results and field observations clearly indicated that yak can be protected against FMD with a good quality vaccine with FMD serotype(s) matching current, regionally circulating FMD virus.     

Modulatory function of NMDA glutamate receptor on MC<Subscript>3</Subscript>/MC<Subscript>4</Subscript> receptors agonist-induced hypophagia in neonatal meat-type chicken

Melanocortin 3 and 4 receptors (MC₃R and MC₄R) are known as the main receptors for melanocortin-induced hypophagia in mammalian and poultry. Also, central glutamatergic system has mediatory role on function of the melanocortin system in some brain areas. So, the aim of the current study was to determine the role of MC₃/MC₄ receptors agonist on food intake and its interaction with glutamatergic in 3-h food-deprived (FD₃) neonatal broilers. In experiment 1, chickens were intracerebroventricular (ICV) injected with control solution, MTII (MC₃/MC₄ receptors agonist; 2.45, 4.8 and 9.8 pmol). In experiment 2, control solution, SHU9119 (MC₃/MC₄ receptors antagonist; 0.5, 1 and 2 nmol) were ICV injected. In experiment 3, birds ICV injected with control solution, SHU9119 (0.5 nmol), MTII (9.8 pmol) and co-injection of the SHU9119 + MTII. Experiments 4–8 were similar to experiment 3, except birds injected with MK-801 (NMDA glutamate receptors antagonist, 15 nmol), CNQX (AMPA glutamate receptors antagonist; 390 nmol), AIDA (mGLUR₁ glutamate receptors antagonist; 2 nmol), LY341495 (mGLUR₂ glutamate receptors antagonist; 150 nmol) and UBP1112 (mGLUR₃ glutamate receptors antagonist; 2 nmol) instead of SHU9119. Then, cumulative food intake was recorded until 120 min after injection. According to the results, dose dependent hypophagia observed after ICV injection of the MTII (p < 0.05). ICV injection of SHU9119 significantly increased food intake in birds (p < 0.05). Co-injection of SHU9119 + MTII significantly inhibited MTII- induced hypophagia in neonatal chicks (p < 0.05). In addition, hypophagia- induced by MTII was significantly attenuated with co-injection of MTII + MK-801(p < 0.05). These results suggested MC₃ and MC₄ receptors have inhibitory role on food intake and this effect is probably mediated by NMDA glutamate receptors in neonatal chickens.     

Efficiency of methods applied for goat estrous synchronization in subtropical monsoonal climate zone of Southwest China

Two experiments were undertaken to select the efficient method applied for goat estrous synchronization. In experiment 1, a total of 120 does (Capra hircus) were divided into five groups with a randomized block design, and the does of treatment 1 were synchronized by intravaginal sponges impregnated with 30 mg Levonorgestrel inserted for 10 days. Does of treatments 2, 3, and 4 were treated with further injection of 25 IU follicle-stimulating hormone (FSH), 0.05 mg prostaglandin F2 alpha (PGF_2α), and 25 IU FSH + 0.05 mg PGF_2α at sponge withdrawal, respectively. The does in the control group (n = 40) without estrous synchronization treatment and natural estrous does were observed. In experiment 2, a total of 140 does in five goat farms in breeding and non-breeding seasons were treated with the selective efficient procedure. The results presented that all the employed treatments were capable of inducing and synchronizing estrous goats. According to estrous response and economy, the use of intravaginal sponges impregnated with 30 mg Levonorgestrel and 0.05 mg PGF_2α (treatment 3) is the first choice for estrous synchronization, and 95.0% of synchronized does demonstrated estrus, which was significantly higher than that of treatment 1 (P < 0.05) and control group (P < 0.01). The percentages of ovulating of treatments 3 and 4 were the same (95.0%), which were significantly higher than that of treatment 1 (P < 0.01). The ovulation rates among different groups were not significant (P > 0.05). When the selective procedure was applied to five goat farms, 85.7% (120/140) of does demonstrated estrus, and the kidding percentage, litter size, and prolificacy rate were 53.6%, 0.95, and 177%, respectively.     

Wild ostrich (<Emphasis Type="Italic">Struthio camelus</Emphasis>) ecology and physiology

This work discusses some of the important considerations of wild ostrich evolution, behaviour and ecology, as items included in ostrich production. In the process considerable research was conducted by collating information from peer-reviewed papers; textbooks; manuals; and PubMed and Agricola searches. Selected areas reviewed included activity of ostriches; feeding and water needs; sexual maturity; egg laying and natural incubation; selected physiological parameters; and predation. There is an immediate and urgent need to conserve and protect the rapidly declining populations of wild ostriches with the committed involvement of governments and funding bodies.     

Protection of mice against <Emphasis Type="Italic">Brucella abortus 544</Emphasis> challenge by vaccination with recombinant OMP28 adjuvanted with CpG oligonucleotides

Brucella abortus, a gram negative, facultative intracellular pathogen causes brucellosis in many animal species and humans. Although live, attenuated vaccines are available against this infection, they suffer from certain limitations. Therefore, the development of an effective subunit vaccine against brucellosis is an area of intense research. The outer membrane proteins (OMPs) of Brucella species have been extensively studied for its immunogenicity and protective ability. We have investigated the potential of CpG ODN to enhance the immunogenicity and protective efficacy of recombinant 28 kDa outer membrane protein (rOMP28) of Brucella melitensis. The study demonstrated vigorous immunoglobulin G (IgG) response of OMP28. The administration of rOMP28 with CpG caused increased cell mediated immune response in terms of induced IgG2a, T-cell proliferation and up-regulation of type I cytokine expression. In contrast, the free antigen suppressed the interferon gamma (type I cytokine) production on in-vitro stimulation of spleenocytes. The result indicates the role of OMP28 in the down regulation of IFN-γ production. Moreover, the B. abortus S-19 vaccinated mice showed highest production of IL-4 and IFN-γ. The protective ability of the antigen was evaluated by systemic bacterial clearance after challenging the mouse with B. abortus 544 pathogen. The level of protection was significant in rOMP28+CpG treated mice but was lower than the required level. The results of the present study indicate that rOMP28 could be an immunogen capable of inducing both humoral and cellular immune response. The humoral response was biased towards Th1 type when it was co-administered with CpG.     

Sero-epidemiological investigation of bovine toxoplasmosis in traditional and smallholder cattle production systems of Tanga Region,Tanzania

In view of the worldwide importance of Toxoplasma gondii and the fragmented information on the seroprevalence of the disease in animals in Tanzania, a study, using the modified Eiken latex agglutination test (LAT), was conducted from May 2003 to January 2004 to determine the prevalence of antibody to T. gondii in 130 randomly selected farms comprising 655 cattle. The overall seroprevalence of T.gondii antibodies in cattle and farms were 3.6% and 13%, respectively. Risk factors for animal and herd-level toxoplasmosis seropositivity were tested using multivariable logistic regression to control for confounding factors. Cattle managed under traditional husbandry practises were more likely to be seropositive than those managed under smallholder practises (48% versus 4.7%; p < 0.01). Herd size of ≥ 9 cattle were at greater risk of acquiring infection than herds holding fewer animals [≤ 9 cattle], (odd ratio [OR] = 3.99; 95% confidence interval [CI], 0.97–16.48; P = 0.001). We concluded that seroprevalence at herd level was high and relatively low at animal level, possibly due to the reduced susceptibility of cattle to T.gondii infection as compared to goats and sheep. The high seroprevalence in animals managed by traditional husbandry practise suggests that the parasite is widely distributed in the environment and could pose a public health threat to the people living in those areas.     

Yield and mineral content of ten enset (<Emphasis Type="Italic">Ensete ventricosum</Emphasis>) varieties

A study was conducted to evaluate the macro and trace mineral contents of ten enset varieties collected from Sidama zone of southern Ethiopia. Samples of leaf lamina, leaf midrib, pseudostem and corm were taken from ten enset varieties at the age of 5 to 6 years during the main rainy season. The dry weight of each variety and fraction were also determined. Mineral contents in fractions of different enset varieties were analysed and compared with nutrient requirements of ruminants. The contribution of different enset fractions to the total dry weight was variable (P < 0.05), the highest being from pseudostem and the lowest from leaf lamina. There were varietal differences (P < 0.05) in macro and trace mineral content in different fractions except phosphorus (P) content of leaf lamina. Most enset fractions were rich sources of major minerals such as P, potassium (K), calcium (Ca) (except corm) and magnesium (Mg). Sodium (Na) content was very low. Most fractions were rich in iron (Fe) and manganese (Mn), but deficient in copper (Cu), except leaf lamina. Zinc (Zn) content was high in corm, but low in other fractions. This account of the macro and trace mineral content of different enset varieties and fractions could help in strategic supplementation intended to alleviate mineral deficiencies.     

Morphology and changes of chloride cell of <Emphasis Type="Italic">Rutilus rutilus Caspicus</Emphasis> (Cyprinidea,teleost) in Caspian sea

An ultrastructural study was performed on chloride cells of euryhaline R.r.Caspicus of south of Caspian Sea. The chloride cells are distributed in the interlamellar region of filaments. They are oval to elongated form with an apical positioned nucleus, expanded tubular system and heteromorphic mitochondria. These cells are surrounded by pavement cell and accessory cell. A small and depressed surface formed by pavement cells is in contact with the aquatic milieu. There is also channel system in accessory cells. One of the typical features was the important changes in microtubules and mitochondria of chloride cells in some fishes. Swelling and rupture of cristae and degeneration of microtubules were from these changes.