Flight distance of dairy cows and its relationship to daily routine management procedures and productivity

The objectives of this study were to determine to what extent the flight distance of cows to humans was influenced by sire and management procedures before and after maturity, and whether there was a correlation between the flight distance and productivity on commercial dairy farms. Flight distance of 84 Holstein cows, the stockperson's daily routine management procedures and production performance were recorded repeatedly on eight commercial dairy farms. The management procedures for the animals at the suckling, growing, lactating and dry stages were classified into four categories by degree of tactile interactions between the stockperson and the animal: hand procedures with touch on (category A), nearby (category B) and apart (category C) from the animal, and machinery procedures (category D). There was no apparent sire effect on flight distance ( P  = 0.08), whereas the flight distance ranged from 1.17 ± 0.86 to 4.47 ± 2.01 m by farm ( P  < 0.01), and gradually shortened with repetition ( P  < 0.05). Regression analysis indicated that the length of time of category B at the suckling stage and category B at the dry stage accounted for 37% and 32% of the variation in flight distance, respectively. As for the total time of the four procedure categories, growing stage was the prime predictor of flight distance, which accounted for 36% of the variation. Flight distance tended to correlate with the first calving age ( r  = 0.66, P  = 0.07). These results suggest the importance of non-producing periods, before maturity and during the dry period, on the subsequent and lifelong advantages of a good relationship between the stockperson and their animals.     

草莓果实含水量对品质的影响

将土壤水分控制在不同水平，获得了130个不同含水量的果实，分析表明：随着果实含水量的减少，果实大小、滴定酸含量降低，可溶性总糖、糖酸比、色相和硬度增加。在提高糖含量的过程中，蔗糖、葡萄糖和果糖提高的幅度并不一样，从而改变了3种单糖占可溶性总糖的比例，果实含水量与果实Brix、糖酸比的相关系数为－0.71和－0.61。     

管网安全性水力评价指标的研究

针对日本国正在运行的绫川地区管网的事故 (漏水 )情况 ,从水力学角度分析了事故频度与管道加权平均流速、最大及最小水压积算值比值、安全率、平均最大及最小水压、最大水锤压积算值比值等因素的关系 ,得出影响系统安全的主要水力学因素有负压、最大水压积算值比率、安全率。对于均匀坡度的管道系统 ,安全率是评价系统水力安全性的重要指标。     

Molecular and immunochemical characteristics of monoclonal and recombinant antibodies selective for the triazine herbicide simetryn and application to environmental analysis

A monoclonal antibody (mab) selective for the thiomethyl-s-triazine herbicide simetryn was obtained and characterized in enzyme-linked immunosorbent assay (ELISA). An IC(50) value for simetryn was 8.5 ng/mL, and the detection range extended from 1.1 to 70 ng/mL in ELISA. The cDNAs encoding variable heavy chain (VH) and variable light chain (VL) of the mab were cloned to produce various recombinant antibodies. Single-chain variable fragment (scFv) antibodies derived from the mab were characterized in ELISA and showed similar reactivities and specificities to the parent mab. A urea denaturation test revealed that the scFv antibodies bound to simetryn were more stable than those in the absence of antigen. A sandwich ELISA based on VH and VL fragments of the mab was successfully developed and showed similar sensitivity to those based on the mab and scFv antibodies in ELISA. In the recovery experiments using spiked environmental samples, the results obtained in ELISA based on the mab were favorably correlated with those by HPLC.     

Effects of an 'enrichment feeder' on behavior and feather conditions of caged laying hens

The objective of this study was to compare the behaviors and feather conditions of caged laying hens fed by two different types of feeders. Seven tennis balls were placed on the feed trough to hide the feed for each of 6 experimental cages (treatment B). The same feed troughs without balls were used for 6 control cages (treatment NB). Forty-eight commercial white leghorn type hens were housed as 4 birds per cage (474 cm² per bird). The experimental period was from 22 to 32 weeks of age. At 28 weeks of age, the hens spent more time feeding in treatment NB (35%) than in B (27%). On the other hand, prefeeding behavior (extension of the neck over the trough or pecking at the balls) occupied more time in B (14%) than in NB (6%). The birds in B spent more time thrusting (thrusting other birds aside and trying to eat) than did the birds in NB (2 vs 0%). At 32 weeks of age, the mean proportion of hens feeding and prefeeding behavior in both treatments was similar to those at 28 weeks of age; however, differences of the behavior between the B and NB were relatively small. Feather damage on a scale of 0 (no damage) to 15 (denuded) increased with age, and the scores in B were less than those in NB at 27 weeks (0.75 vs 1.37), although not at 32 weeks. Egg production in the two treatments was the same, and the type of feeder used did not affect body weight. This device might provide hens with a more attractive environment than the conventional feeders; however, the enrichment feeder might need more improvement for the welfare of caged laying hens.     

Precocious development of the digestive system in relation to early appearance of piscivory in striped bonito Sarda orientalis larvae

ABSTRACT: Striped bonito Sarda orientalis larvae and juveniles were reared in a laboratory from hatching to 14 days post hatching, and the development of their digestive system was investigated histologically. On day 2 (first feeding day), the larval-type digestive system was differentiated. On day 3, a blind sac with densely distributed gastric glands developed and pyloric ceca appeared, suggesting that the digestive system was attaining adult-type structure. The yolk was completely absorbed on day 4. Bonito larvae preyed on rotifers and/or Artemia nauplii on day 2, but almost the whole gut was occupied by fish larvae from day 4. In the striped bonito, the adult-type digestive system was established right after first feeding, and this precocious development was well synchronized with the appearance of piscivory.     

A low pathogenic H5N2 influenza virus isolated in Taiwan acquired high pathogenicity by consecutive passages in chickens

H5N2 viruses were isolated from cloacal swab samples of apparently healthy chickens in Taiwan in 2003 and 2008 during surveillance of avian influenza. Each of the viruses was eradicated by stamping out. The official diagnosis report indicated that the Intravenous Pathogenicity Indexes (IVPIs) of the isolates were 0.00 and 0.89, respectively, indicating that these were low pathogenic strains, although the hemagglutinin of the strain isolated in 2008 (Taiwan08) had multibasic amino acid residues at the cleavage site (PQRKKR/G). In the present study, these H5N2 viruses were assessed for their intravenous and intranasal pathogenicity for chickens. It was examined whether Taiwan08 acquires pathogenicity through consecutive passages in chickens. Intravenous pathogenicity of Taiwan08 depended upon the age of the chickens used for the IVPI test; all of the eight-week-old chickens intravenously inoculated with Taiwan08 showed clinical signs but survived for ten days post inoculation (IVPI=0.68), whereas all the six-week-old chickens died (IVPI=1.86). Taiwan08-P8, which were passaged in chickens for eight times, killed all the eight-week-old chickens (IVPI=2.36). The four-week-old chickens died after intranasal inoculation of Taiwan08-P8, indicating that Taiwan08 must have become highly pathogenic during circulation in chicken flocks. These results emphasize the importance of a stamping out policy for avian influenza even if the IVPI of the causal virus is low.     

Association of an SNP marker in exon 24 of a class 3 phosphoinositide‐3‐kinase (PIK3C3) gene with production traits in Duroc pigs

A C?T single nucleotide polymorphism (SNP) on exon 24 of the porcine class 3 phosphoinositide‐3‐kinase (PIK3C3) gene is considered a possible genetic marker for selecting backfat (BF) thickness and carcass fat, although only one study has published results on its effects by performing experiments on a single resource family. We analyzed the association of this PIK3C3 polymorphism with production traits in 739 Duroc pigs. The C allele frequency was 67.9% in our study population. PIK3C3 polymorphism showed significant effects on average daily weight gain (ADG), BF thickness, intermuscular fat content (IMF), and the size of the loin eye muscle area (EMA). The C alleles increased ADG, BF and IMF, and decreased EMA. The predicted differences in traits between the homozygous pigs of the C and T alleles were 40 g/day for DG, 1.2 mm for BF, 0.44% for IMF, and 1.6 cm² for EMA. Furthermore, the statistical models for estimating the breeding values of each trait had lower Akaike's information criterion values when adding PIK3C3 genotype information. We therefore confirmed that the polymorphism in PIK3C3 (C2604T) has the potential to be a genetic marker for production traits in Duroc pigs.