Morphological characteristics of blood cells in monitor lizards: is erythrocyte size linked to actual body size?

Blood cell morphology and count are not uniform across species. Recently, between‐species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove‐dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass‐specific metabolic rate decreases with body size and the cell volume‐to‐surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment.     

Development and survival of Haemonchus contortus infective larvae derived from sheep faeces under sub-tropical conditions in the Potohar region of Pakistan

Assessment on the development and survival of Haemonchus contortus larvae was made to evaluate the influence of microclimatic variables viz., relative humidity (%), temperature (°C), rainfall (mm) and intensity of sunlight (hrs). Pasture plots in a sub-tropical area, Pakistan were contaminated with H. contortus eggs at the start of every month. The plots were sampled on fortnightly basis after contamination for three consecutive months. The overall pattern indicated the most favorable conditions for survival, development and translation to herbage was during the wet season from July to October and the least favorable was during the dry season from April to June. Peak infective larvae (L₃) recovery was during the 15–45 day interval for each plot and the lowest number was during the 75–90 day interval. Herbage was collected in the morning, afternoon and evening and greatest recovery of L₃ was in the morning time and least in the afternoon. The number of L₃ on pasture was directly related to the pattern of rainfall and relative humidity with a significant (P < 0.05) positive correlation and temperature and intensity of sunshine were negatively correlated (P < 0.05). The results suggest that pastures can remain infective for up to 2 months and become relatively clean by 90 days after contamination. Thus, long pasture rest periods, especially during the high risk wet season, may be a helpful strategy to reduce the infection levels.     

Detection of Chlamydiaceae in ocular swabs from Australian pre‐export feedlot sheep

Infectious Ovine Keratoconjunctivitis (IOK) is a contagious ocular disease of sheep. A range of organisms have been observed as the aetiological agents of IOK. In this study, the presence of chlamydial pathogens (C. pecorum, C. abortus, C. psittaci) in conjunctival swabs was tested for. The swabs were collected from sheep with varying grades of IOK in an Australian pre‐export feedlot. The sheep had been rejected from a shipment because of the eye disease. The relative contribution of chlamydial pathogens to IOK and the rejection of animals was evaluated. In total, 149 conjunctival swabs were taken from rejected sheep (IOK Grades 1 to 6; n = 126) as well as those with healthy eyes (Grade 0; n = 23). Screening for chlamydial pathogens was done using species–specific qPCR assays. Chlamydial DNA was detected in 35.6% (53/149) of conjunctival samples. C. pecorum was the most predominant species with an overall prevalence of 28.9% (43/149). C. psittaci prevalence was 6.7% (10/149). Both organisms were detected in healthy as well as IOK‐affected eyes. All swabs tested negative for C. abortus. The results from this study demonstrate that Chlamydia spp can be readily detected in sheep presenting with IOK. The zoonotic C. abortus was not detected in any of the samples in this study, providing further evidence to the suggestion that this pathogen remains absent from Australia. Although the exact contribution of Chlamydia spp in the IOK pathogenesis is unclear, such studies are anticipated to be of benefit to Australian domestic and live export production systems.     

Genetic‐Quantitative Study of the First‐Service Pregnancy Probability of Murrah Heifers

Because of the importance of reproduction in stock breeding systems, it is necessary to find selection criteria that increase reproductive efficiency. The aim of this study was to estimate genetic parameters for the probability of conception on first service (PROB) in Murrah heifers, and its association with other traits of economic interest [age at first calving (AFC), service period, calving interval and milk yield at 270 days], with the purpose of evaluating their use as selection criteria. Reproductive information and first lactation records of 1200 Murrah heifers were used to perform two‐trait analyses between PROB and the other characteristics. Bayesian inference was used to estimate the variance components, considering PROB as threshold and the other as linear factors. The results demonstrate that this trait has heritability of 0.15, indicating the possibility of a genetic gain by using it for selection. With respect to the genetic correlation estimates, the only high‐magnitude association was with AFC (?0.899), which is the current criterion indicating sexual precocity of females. In the light of the parameters estimated, the first‐service pregnancy rate is an alternative for indication of sexual precocity, although presenting a smaller genetic gain than the current standard AFC. Nevertheless, additional research should be conducted regarding this trait to assess the economic importance of its use in dairy buffalo production systems.     

Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity

The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages.     

Comparison of ultrasonographic findings with clinical activity index (CIBDAI) and diagnosis in dogs with chronic enteropathies.

Intestinal wall thickness is neither a specific nor sensitive ultrasound parameter for detecting intestinal inflammation. We hypothesize that mucosal echogenicity, lymphadenomegaly, and secondary findings of the gastrointestinal tract would be more sensitive and specific markers for detecting and differentiating causes of chronic inflammatory bowel disease in dogs. Fifty-six client-owned dogs with chronic diarrhea and 10 control dogs were examined with two-dimensional, gray-scale ultrasound (time 0, 4, and 10 weeks post therapy) and small intestinal mucosal biopsies were performed at the 0- and 4-week time points. The clinical activity was assessed at each time point using the canine inflammatory bowel disease activity index (CIBDAI). Fifty-one dogs had inflammatory infiltration of the duodenal mucosa and were divided into three groups, food-responsive disease, idiopathic inflammatory bowel disease, and protein-losing enteropathy, based on their response to the different treatments and histology. Two different patterns of increased echogenicity of the mucosa were detected: hyperechoic speckles and hyperechoic striations. A normal, hypoechoic bowel mucosa in dogs with chronic diarrhea had a sensitivity of 80% and a specificity of 81% for the diagnosis of food-responsive disease. Hyperechoic striations had a sensitivity of 75% and a specificity of 96% for dogs with protein-losing enteropathy. Hyperechoic speckles were non-specific for diagnosing inflammatory bowel disease. There was a significant relationship between ultrasound score and CIBDAI at t0, but not following therapy. Mucosal echogenicity may be a better parameter for detecting inflammatory bowel disease than bowel wall thickness in dogs with chronic diarrhea.     

注射用头孢呋辛钠的安全性试验研究

通过试验研究对注射用头孢呋辛钠的安全性进行评价。采用豚鼠和家兔分别进行本品的全身用药过敏性、血管和肌肉局部刺激性及家兔红细胞体外溶血性试验研究。结果显示本品对豚鼠无明显全身过敏性、静脉注射对家兔耳缘静脉无明显局部刺激性、对家兔肌肉注射给药无明显局部刺激性、对家兔红细胞无明显体外溶血性。表明本品的各项安全性均良好,为实际应用提供了有力依据。     

Organs development,gene expression and health of Atlantic salmon (Salmo salar L.) fed genetically modified soybeans compared to the near‐isogenic non‐modified parental line

The present experiment was conducted to study the possible effects of genetically modified (GM), full‐fat soybean meal (FFSBM) from Round‐up Ready^® soybeans compared to its parental, and closest near‐isogenic, non‐modified (nGM) soybean variety, added at moderate (150 g kg^?1) and high (300 g kg^?1) inclusion levels. The fish showed a high specific growth rate (SGR 1.27–1.52), and nearly doubled their body weight (BW), with final weights varying from 1009 to 1110 g. Increased levels of dietary FFSBM, independent of the soy being GM or not, significantly decreased mean values of SGR, thermal growth rate, condition factor, final BW, liver somatic index, lipid efficiency ratio, apparent digestibility coefficients (ADC) of protein and gross energy, liver lipid content and plasma cholesterol, and significantly increased ADC of starch and muscle fatty acid levels of 18:3n‐3, 20:4n‐6, 20:5n‐3 and total n‐3. Increasing dietary GM FFSBM significantly increased feed conversion ratio, and significantly decreased protein efficiency ratio, ADC of lipid and dry matter and plasma triacylglycerol (TAG) levels. Spleen somatic index was significantly larger in fish groups fed GM FFSBM compared to groups fed nGM FFSBM, which might indicate a possible immune response exerted by the GM soybeans. Mean normalized expression of heat shock protein 70 mRNA in distal intestine was significantly up‐regulated while normalized expression of catalase in liver was down‐regulated, in fish fed FFSBM compared to fish fed FM. In conclusion, substituting moderate to high levels of GM Round‐up Ready^® FFSBM in diets for Atlantic salmon and compared to the closest near‐isogenic counterpart available, resulted in many effects independent of the soy being GM or not, but with the notable exceptions of enlarged spleen and lowered plasma TAG.