Effects of road type during transport on lamb welfare and meat quality in dry hot climates

This study determined whether transporting lambs on paved (PR) or unpaved roads (UR) for 3 h had an effect on plasma stress indicators (cortisol, lactate, glucose, creatine kinase [CK], red blood cells, white blood cells, hematocrit, and neutrophil/lymphocyte [N/L] ratio) and instrumental meat quality (pH24, bruising score, water holding capacity [WHC], color, and texture). A total of 48 Rasa Aragonesa male lambs were used that were approximately 100 days old (12.5 kg ± 1.64, carcass weight). The results suggest that transport on unpaved roads had a significant influence on physiological and hematological stress parameters. Road type had a significant effect on all variables, except for white and red blood cells, and hematocrit levels. The UR lambs had significantly higher (at least p ≤ 0.01) cortisol, lactate, glucose, and CK levels and a higher N/L ratio than PR lambs. Meat from UR lambs had some dark-cutting characteristics, with a darker color, higher ultimate pH, and higher tenderness values than PR. In conclusion, lambs transported on unpaved roads had a more intense stress response and poorer meat quality than lambs transported on paved roads. An effort to improve the logistics associated with route planning is necessary to prevent welfare problems during transport to slaughter.     

Primary hyperaldosteronism: expanding the diagnostic net

PRACTICAL RELEVANCE: Primary hyperaldosteronism is probably the most common adrenocortical disorder in cats. As in humans, it is often unrecognised, which excludes a potentially large number of cats from appropriate treatment. PATIENT GROUP: Affected cats present at a median age of 13 years (range 5-20 years). A breed or sex predilection has not been documented. The excessive secretion of mineralocorticoids usually leads to hypokalaemia and/or systemic arterial hypertension. Most affected cats present with muscular weakness and/or ocular signs of arterial hypertension. DIAGNOSTICS: In any cat presenting with hypokalaemia and/or arterial hypertension, other potential causes should be excluded. The ratio of plasma aldosterone concentration to plasma renin activity (aldosterone:renin ratio) is currently the best screening test for feline primary hyperaldosteronism. Diagnostic imaging is required to differentiate between adrenocortical neoplasia and bilateral hyperplasia, and to detect any distant metastases. CLINICAL CHALLENGES: The differentiation between adrenocortical neoplasia and bilateral hyperplasia is imperative for planning optimal therapy, but the limited sensitivity of diagnostic imaging may occasionally pose a problem. For confirmed unilateral primary hyperaldosteronism, unilateral adrenalectomy is the treatment of choice, and offers an excellent prognosis, but potentially fatal intra- and postoperative haemorrhage is a reported complication and risk factors have yet to be identified. EVIDENCE BASE: Only a few case reports are available on which to base the optimal diagnostic and therapeutic approach to feline primary hyperaldosteronism. This article reviews the physiology of aldosterone production and the pathophysiology of primary hyperaldosteronism, and summarises the currently available literature on the feline disease. Practical suggestions are given for the diagnostic investigation of cats with suspected primary hyperaldosteronism.     

Simulation of genetic control of reproduction in beef cows. II. Derived genetic parameters

A stochastic computer simulation model was used to predict heritability (h2) and repeatability (t) of derived reproductive traits in beef cattle as a function of underlying, normally-distributed genetic variation in interval from calving to first estrus (postpartum interval) and single-service conception rate. Traits simulated were mating rate, first-service conception rate, overall conception rate, date of first service, number of services during a 63-d breeding season, calving date and postpartum interval. Weight of calf weaned was also simulated on a per-cow-exposed, per-cow-mating, per-cow-calving, per-calf-weaned or adjusted 205-d basis. Derived estimates of h2 for mating rate and date of first service were not significantly different from 0, reflecting the high proportion of cows that were predicted to cycle within the first 21 d of breeding. Estimates of h2 were significant and approached the level of input h2 for overall and first-service conception rate and number of services, suggesting that these traits may be potential selection criteria. Values of h2 for calving date were significant but considerably smaller than input h2. Estimates of t were much larger than h2 for date of first service and calving date, even when no nonadditive genetic or permanent environmental effects were explicitly simulated. Estimates of h2 for weaning weight per cow exposed and especially for weaning weight per cow calving (in the presence of random calf death losses) were much lower than underlying h2 values. Culling of open cows generally reduced genetic variances of derived reproductive traits to negligible levels within three calf crops.     

Genetic (co)variance components for ewe productivity traits in Katahdin sheep

The objective of this study was to estimate genetic parameters, in Katahdin sheep, for total weight of litter weaned per ewe lambing (TW) and its components, number of lambs born (NB), number of lambs weaned (NW), and average weight of lambs weaned (AW) measured as traits of the ewe. Weaning weights of lambs (WW) were adjusted to 60 d of age and for effects of ewe age, lamb sex, and type of birth and rearing and averaged over all lambs in the litter to obtain AW. The 60-d age-adjusted WW were adjusted for ewe age and lamb sex and summed over all lambs in the litter to obtain TW. A total of 2,995 NB and NW records, 2,622 AW, and 2,714 TW records were available from 1,549 ewes (progeny of 235 sires) over 4 yr. Heritabilities were initially estimated for each trait from univariate REML analyses. Estimates of genetic correlations were obtained from bi- and trivariate analyses. Models for NB, NW, AW, and TW included random ewe additive and permanent environmental effects. A random service sire effect was also fit for AW and TW. Heritabilities of TW, NB, NW, and AW from univariate analyses were 0.12, 0.12, 0.09, and 0.13 (all P < 0.01), respectively. Permanent environmental effects were significant (P < 0.01) for TW and AW. Genetic correlations of TW with NB, NW, and AW ranged from 0.27 to 0.33, 0.88 to 0.91, and 0.72 to 0.76, respectively; those of NB with NW and AW ranged from 0.70 to 0.75 and -0.01 to 0.02, respectively; and that between NW and AW ranged from 0.40 to 0.55. Genetic parameters were also obtained for lamb survival to weaning (LS) and WW measured as traits of the lamb, and the relationships between WW of the ewe as a lamb and her subsequent records for NB and NW were also estimated. A total of 5,107 LS and 5,444 WW records were available. Models for WW and LS included random animal and maternal genetic, maternal permanent environmental, and litter effects. Heritability of WW ranged from 0.15 to 0.20. There was no evidence of genetic effects on LS. Direct genetic correlations of WW with NB and NW were not significantly different from zero. The correlation between maternal genetic effects on WW, and animal genetic effects on NW, averaged 0.35. Results of this study indicate that there are no major antagonisms among TW and its components, so that selection for TW would not have adverse effects on any component traits and vice versa. Maternally superior ewes for WW appear to also be somewhat superior for NW.     

Breeding objectives for Targhee sheep

Breeding objectives were developed for Targhee sheep under rangeland production conditions. Traits considered were those for which EPD were available from the US National Sheep Improvement Program and included direct and maternal effects on 120-d weaning weight (WW and MM, respectively); yearling weight (YW); yearling fleece weight, fiber diameter, and staple length; and percent lamb crop (PLC), measured as the number of lambs born per 100 ewes lambing. A bioeconomic model was used to predict the effects of a change of 1 additive SD in EPD for each trait, holding all other traits constant at their mean, on animal performance, feed requirements, feed costs, and economic returns. Resulting economic weightings were then used to derive selection indexes. Indexes were derived separately for 3 prolificacy levels (1.41, 1.55, and 1.70 lambs/ewe lambing), 2 triplet survival levels (50 and 67%), 2 lamb pricing policies (with or without discounting of prices for heavy feeder lambs), and 3 forage cost scenarios (renting pasture, purchasing hay, or reducing flock size to accommodate increased nutrient requirements for production). Increasing PLC generally had the largest impact on profitability, although an increase in WW was equally important, with low feed costs and no discounting of prices for heavy feeder lambs. Increases in PLC were recommended at all 3 prolificacy levels, but with low triplet survival the value of increasing PLC eventually declined as the mean litter size increased to approximately 2.15 lambs/ewe lambing and above. Increasing YW (independent of WW) increased ewe maintenance costs and reduced profitability. Predicted changes in breeding values for WW and YW under index selection varied with lamb pricing policy and feed costs. With low feed costs or no discounts for heavy lambs, YW increased at a modest rate in association with increasing WW, but with high feed costs or discounting of heavy lambs, genetic trends in WW were reduced by approximately 50% to constrain increases in YW. Changes in EPD for MM or fleece traits generally had smaller effects on profitability than changes in PLC, WW, and YW. Two indexes designed to address current rangeland production conditions (low forage costs and discounting of heavy feeder lambs) or more intensive and integrated production with retained ownership and value-based marketing of lambs (higher forage costs and no discounting of heavy lambs) were anticipated to meet the needs of most Targhee producers.     

Effect of vaccination on parvovirus antigen testing in kittens

OBJECTIVE: To determine the frequency and duration of feline panleukopenia virus (FPV) vaccine-induced interference with fecal parvovirus diagnostic testing in cats. DESIGN: Prospective controlled study. ANIMALS: Sixty-four 8- to 10-week-old specific-pathogen-free kittens. PROCEDURES: Kittens were inoculated once with 1 of 8 commercial multivalent vaccines containing modified-live virus (MLV) or inactivated FPV by the SC or intranasal routes. Feces were tested for parvovirus antigen immediately prior to vaccination, then daily for 14 days with 3 tests designed for detection of canine parvovirus. Serum anti-FPV antibody titers were determined by use of hemagglutination inhibition prior to vaccination and 14 days later. RESULTS: All fecal parvovirus test results were negative prior to vaccination. After vaccination, 1 kitten had positive test results with test 1, 4 kittens had positive results with test 2, and 13 kittens had positive results with test 3. Only 1 kitten had positive results with all 3 tests, and only 2 of those tests were subjectively considered to have strongly positive results. At 14 days after vaccination, 31% of kittens receiving inactivated vaccines had protective FPV titers, whereas 85% of kittens receiving MLV vaccines had protective titers. CONCLUSIONS AND CLINICAL RELEVANCE: Animal shelter veterinarians should select fecal tests for parvovirus detection that have high sensitivity for FPV and low frequency of vaccine-related test interference. Positive parvovirus test results should be interpreted in light of clinical signs, vaccination history, and results of confirmatory testing. Despite the possibility of test interference, the benefit provided by universal MLV FPV vaccination of cats in high-risk environments such as shelters outweighs the impact on diagnostic test accuracy.     

Impact of trace metal contamination and in situ remediation on microbial diversity and respiratory activity of heavily polluted Kastanozems

Biology and Fertility of Soils - Agriculturally used soils (Kastanozems) of experimental fields in the Mashavera Valley in southeast Georgia show various degrees of trace metal contamination (Cd,...     

Single neurons in the monkey hippocampus and learning of new associations

The medial temporal lobe is crucial for the ability to learn and retain new declarative memories. This form of memory includes the ability to quickly establish novel associations between unrelated items. To better understand the patterns of neural activity during associative memory formation, we recorded the activity of hippocampal neurons of macaque monkeys as they learned new associations. Hippocampal neurons signaled learning by changing their stimulus-selective response properties. This change in the pattern of selective neural activity occurred before, at the same time as, or after learning, which suggests that these neurons are involved in the initial formation of new associative memories.     

基于AEZ模型的我国马铃薯产量潜力的农作制区划分析

根据联合国粮农组织(FAO)和国际应用系统分析研究所(IIASA)基于中国1961～1997年的统计资料(经多方校正)共同开发的AEZ模型,运用GIS平台计算了中国41个农作制亚区的马铃薯生产潜力,并指出了单产最高潜力分布区域。研究结果表明:我国马铃薯的最高产量潜力大约将是目前产量的2～3倍。这对我国马铃薯高产育种及栽培具有重要参考意义。     

Unusual Glycosaminoglycans from a Deep Sea Hydrothermal Bacterium Improve Fibrillar Collagen Structuring and Fibroblast Activities in Engineered Connective Tissues

Biopolymers produced by marine organisms can offer useful tools for regenerative medicine. Particularly, HE800 exopolysaccharide (HE800 EPS) secreted by a deep-sea hydrothermal bacterium displays an interesting glycosaminoglycan-like feature resembling hyaluronan. Previous studies demonstrated its effectiveness to enhance in vivo bone regeneration and to support osteoblastic cell metabolism in culture. Thus, in order to assess the usefulness of this high-molecular weight polymer in tissue engineering and tissue repair, in vitro reconstructed connective tissues containing HE800 EPS were performed. We showed that this polysaccharide promotes both collagen structuring and extracellular matrix settle by dermal fibroblasts. Furthermore, from the native HE800 EPS, a low-molecular weight sulfated derivative (HE800 DROS) displaying chemical analogy with heparan-sulfate, was designed. Thus, it was demonstrated that HE800 DROS mimics some properties of heparan-sulfate, such as promotion of fibroblast proliferation and inhibition of matrix metalloproteinase (MMP) secretion. Therefore, we suggest that the HE800EPS family can be considered as an innovative biotechnological source of glycosaminoglycan-like compounds useful to design biomaterials and drugs for tissue engineering and repair.