Mapping genomic regions for reproductive traits in beef cattle: Inclusion of the X chromosome

Although the second largest chromosome of the genome, the X chromosome is usually excluded from genome-wide association studies (GWAS). Considering the presence and importance of genes on this chromosome that are involved in reproduction, the aim of this study was to evaluate the effect of its inclusion in GWAS on reproductive traits (scrotal circumference [SC], early pregnancy [P16] and age at first calving [AFC]) in a Nelore herd. Genotype data from 3,263 animals with the above-mentioned phenotypes were used. The results showed an increase in the variances explained by the autosomal markers for all traits when the X chromosome was not included. For SC, there was an increase of more than 10% for the windows on chromosomes 2 and 6. For P16, the effect was increased by almost 20% for windows on chromosome 5. The same pattern was found for AFC, with an increase of more than 10% for the most important windows. The results indicate that the noninclusion of the X chromosome can overestimate the effects of autosomes on SC, P16 and AFC not only because of the additive effect of the X chromosome itself but also because of its epistatic effect on autosomal genes.     

Retrospective study of owners' perception on home monitoring of blood glucose in diabetic dogs and cats

Home monitoring of blood glucose (HMBG) concentrations has been recommended in the monitoring of human diabetics for 3 decades. During the last number of years, it also gained popularity in long-term follow-up of diabetic cats and dogs. The aim of this retrospective study was to evaluate the practical feasibility of and identify the major problems encountered with HMBG in diabetic pets. A standard questionnaire was filled in by owners of 9 diabetic pets monitored with HMBG. The need for more than 1 puncture to obtain a blood drop, the creation of a sufficient blood drop, the need for assistance in restraining the pet, and the resistance of the pet were the most frequently encountered problems during HMBG. The major obstacles for the owners to start with HMBG were also identified. In conclusion, HMBG is a practical and simple technique for most owners and, overall, owners were satisfied.     

The effect of different isolation procedures on canine leucocyte populations and on lectin-induced lymphocyte proliferation

Proliferation assays performed on peripheral blood mononuclear cells (PBMC) are commonly used in experimental and clinical immunology. A prerequisite for an in vitro assay is the ability to obtain relatively pure populations of mononuclear cells from whole blood, as contaminating polymorphonuclear cells may affect the proliferation of lymphocytes. Purification of canine leucocytes from whole blood is associated with difficulties in obtaining pure lymphocytes in high yields. The aim of this study was to optimize the lymphocyte purification from canine whole blood in terms of total cell recovery and purity, while not influencing the proliferation capacity of the isolated cells. To acquire optimal isolation of canine lymphocytes several density gradient media of different densities and osmolalities were examined. For optimal phagocyte removal, pre-treatment of whole blood with carbonyl iron/arabic gum and/or adherence to fibrinogen pre-coated polystyrene tissue flasks were examined. Lectin-induced proliferation was used as measurement of cell activity of the obtained cell fractions after the different separation procedures. Canine blood pre-treated with carbonyl iron/arabic gum followed by density gradient centrifugation with medium 'G' (density: 1.079 g/cm(3), osmolality: 256 mOsm) and adherence to pre-coated polystyrene tissue flask obtained the best PBMC cultures with a median lymphocyte purity of 88% and a median yield of recovered lymphocytes of 54%. This culture also resulted in the highest proliferation and subsequently the highest stimulation index upon lectin stimulation.     

Morphometric analysis of the corneal endothelium of Yacare caiman (Caiman yacare) using scanning electron microscopy

The objective of this study was to examine the endothelial surface morphology and to perform morphometric analysis of the corneal endothelial cells of Yacare caiman (Caiman yacare) using scanning electron microscopy. Morphometric analysis with regard to polygonality, mean cell area, cell density and coefficient of variation of mean cell area was performed. Cell areas were measured using image analysis software. The normal corneal endothelium of Yacare caiman consisted of polygonal cells of uniform size and shape with interdigitations of the cell borders. Microvilli appeared as protrusions on the cellular surface. The average cell area was 270 +/- 24 microm(2) and the endothelial cell density was 3704 +/- 324 cells/mm(2). The coefficient of variation of cell area was 0.22. This study demonstrates that the Yacare caiman corneal endothelium is similar to those described in other vertebrates.     

MALDI-TOF MS identification of Prototheca algae associated with bovine mastitis

We evaluated the use of MALDI-TOF MS for the identification of 3 major, dairy-associated Prototheca species, namely, Prototheca bovis (formerly P. zopfii genotype 2), P. blaschkeae, and P. ciferrii (formerly P. zopfii genotype 1). The MALDI-TOF MS spectra established for those species were introduced into the reference spectra library of the Bruker Biotyper MALDI-TOF MS analysis software. Next, 31 Prototheca isolates from Holstein cows with mastitis, from herds located in the midwestern area of São Paulo State, Brazil, were subjected to MALDI-TOF MS profiling. MALDI-TOF MS allowed identification of 22 of 27 P. bovis and 3 of 4 P. blaschkeae isolates with scores >2.0, with 5 of 27 P. bovis and 1 of 4 P. blaschkeae isolates identified only to the genus level. With our extended algae database, MALDI-TOF MS can contribute to quick and effective speciation of Prototheca from mastitis cases.     

不同年龄肉牛育肥性能的研究

先用34 头西门塔尔杂交阉牛,按年龄分为2±0.5 岁(8 头)、3±0.5 岁(9 头)、4±0.5 岁(8 头)、5～9 岁(9 头)4 个年龄组,进行了不同年龄组对育肥效果、屠宰性能影响的研究。结果表明,在相同饲养条件下,肉牛的增重速度(P< 0.01)、饲料转化率、大理石花纹等级(P< 0.05)及眼肌面积(P< 0.05)均以3 岁以下为好。随着年龄的增长,虽然屠宰率略微见增(P> 0.05),但肉的品质下降,饲养效果降低。     

Unilateral granulomatous orchitis in a harbour porpoise (Phocoena phocoena): a case report

This case report describes orchitis in a stranded adult sexually mature free-living harbour porpoise (Phocoena phocoena). Orchitis, with or without epididymitis, is a rare finding in harbour porpoises and has been reported to be associated with infection with Brucella species or fungi. This porpoise was examined as part of an ongoing investigation into causes of death in harbour porpoises stranded on the Dutch coast. At necropsy, the animal was in very poor body condition and the most significant pathological change encountered was unilateral chronic granulomatous orchitis. Histologically, the seminiferous tubules were multifocally severely distended by large numbers of macrophages and fewer neutrophils that often showed central necrosis, with intra- and extracellular rod-shaped bacteria that stained negatively with Gram stain. No acid-fast bacteria, fungal elements, or spirochetes were detected when the lesions were stained with Ziehl-Neelsen, Fite-Faraco, Warthin-Starry, and Periodic acid-Schiff stains. Culture of samples taken from the testis revealed a pure culture of a bacterium of the Alcaligenaceae family. Further analysis by biochemistry, fatty acid profiling, and 16S rRNA gene sequencing techniques identified the bacterium as a Castellaniella species. The association of this bacterium with the observed lesions remains uncertain.     

Tansy ragwort poisoning in a horse in southern Ontario

Bizarre behavior, apparent lameness, and colic were noticed in 1 of 3 horses on a pasture overgrown by weeds during a drought. Liver failure and hepatoencephalopathy were diagnosed, caused by pyrrolizidine alkaloid toxicosis associated with consumption of tansy ragwort. The horse made a full recovery when removed from the pasture.     

Effect of GnRH and hCG administration on plasma LH and testosterone concentrations in normal stallions, aged stallions and stallions with lack of libido

Gonadotrophin-releasing hormone (GnRH) (a single intravenous injection with 0.042 mg busereline acetate) was administered to control stallions (n=5), aged stallions (n=5) and stallions with lack of libido (n=5). Jugular blood samples were taken at -10, 0, 10, 20, 40 and 80 minutes after treatment and measured for luteinizing hormone (LH) and testosterone concentrations. A single intravenous injection of hCG (3000 IE) was given 1 day later. Venous blood samples were taken at -60, 0, 15, 30, 60, 120, and 240 minutes after treatment and measured for the testosterone concentration. The experiment was performed in the breeding season. There was a wide variation between stallions in basal concentrations of LH and testosterone. The treatment groups all showed a significant increase in LH and testosterone concentrations after treatment with GnRH. There was a significant difference (P<0.05) between the control, the lack of libido stallions and the aged stallions in the production of LH before and after stimulation with GnRH. The aged stallions had higher basal LH concentrations. GnRH induced a rise in plasma LH in all groups, but the greatest response was observed in aged stallions. No response to GnRH was seen with respect to plasma testosterone. There was an increase in plasma testosterone following hCG; however, this increase was very small in aged stallions. After stimulation with hCG the control and lack of libido stallions had a significant increase (P<0.05) in testosterone production. In conclusion, stimulation with either GnRH or hCG can be a valuable method to test whether the function of the stallion's reproductive endocrine system is optimal.