Factors Affecting the Incidence of Postpartum Fever in Heavy Draft Mares

Postpartum metritis is a common problem in many animal species. In equine medicine, sequelae of postpartum metritis vary from delay in uterine involution to development of systemic acute metritis (SAM), toxemia, and laminitis. Heavy draft mares potentially have higher risk of suffering from SAM than light breed mares. Postpartum fever (PF) mostly appears as a sign of SAM. The purpose of this study is to analyze the factors affecting the incidence of PF in 158 foalings from 62 heavy draft mares by multiple logistic regressions. The objective variable was the incidence of PF, and the explanatory variables were year foaled, month foaled, age of mare, breed of mare (crossbred heavy draft horse vs. Percheron), gestation length, foaling difficulty (easy delivery vs. dystocia), retained fetal membranes, stillbirth, and sex of offspring. Twenty-four out of 158 mares were diagnosed with PF. Stepwise regression analysis showed that breed of dams and foaling difficulty were significant risk factors for PF. Percheron mares had higher risk than crossbred mares (odds ratio: 3.4). Dystocia had higher risk than easy delivery (odds ratio: 3.3). Percheron mares had higher incidence of PF than crossbred mares even in the cases of easy delivery. Risks for damage and contamination of birth canal will be increased especially if the fetal delivery needs assistance. The results of this study suggest that it is necessary to consider the foaling difficulty and the breed of dams for earlier detection of PF in peripartum heavy draft mares.     

家禽瘦素(Leptin)信息传导及其生理功能(续完)

续2009年第4期：上一期总体介绍了瘦素的一般情况,并详细介绍了瘦素受体的结构和基因表达。     

The Effect of Eating Sea Cucumber Jelly on Candida Load in the Oral Cavity of Elderly Individuals in a Nursing Home

We conducted a double-blind randomized controlled study of elderly individuals in a nursing home to investigate the effect of the consumption of jelly containing sea cucumber on their oral Candida load. The jelly contained a hydrolysate of the sea cucumber Stichopus japonicus, which contained triterpene glycosides called holotoxins. The holotoxins worked as a fungicide, and their minimum inhibitory concentrations for Candida albicans were 7 µg/mL. Eight individuals in the nursing home took the sea cucumber jelly for a week and their oral Candida were counted before and after the intervention. Nine individuals took a control jelly without S. japonicus. The sea cucumber jelly showed inhibitory effects on the oral Candida. Thus, daily consumption of the S. japonicus jelly has the potential to reduce the oral Candida load in the elderly in nursing homes.     

Estimation of nutrient excretion factors of broiler and layer chickens in Japan

We estimated the nitrogen (N), phosphorus (P), potassium (K) and magnesium (Mg) excretion factors of broiler and layer chickens in Japan, using two approaches and the latest data available. In the top‐down approach, we determined the nutrient amounts in the feeds and those in the products (i.e. the liveweight gain, eggs), and the national nutrient excretions were determined as the difference between these amounts. We then calculated the nutrient excretion factors by dividing the national excretions by the number of animals. In the bottom‐up approach, we calculated the amounts of nutrients in the feed and product per head using productivity parameters (feed conversion ratio, etc.). The differences between these amounts were considered the nutrient excretion factors. The average nutrient excretion factors of broilers (g/day/head) estimated using the top‐down and bottom‐up approaches were: N, 1.40 and 1.87; P, 0.36, 0.50; K, 0.54, 0.77; Mg, 0.13, 0.18, respectively. The excretion factors obtained by the top‐down approach can be used to calculate the national/regional excretions. The two approaches resulted in almost the same excretion factors for layers, and the average nutrient excretion factors of layers (g/day/head) estimated were: N, 2.20; P, 0.55; K, 0.68; Mg, 0.23. The estimated excretion factors for N (only) are smaller than the reported factors.     

Effect of short-term fasting on hepatic steroid hormone metabolism in cows

In the present study, the effect of 4-day fasting on steroid hormone metabolism in the liver and secretion of LH was examined in cows. Six non pregnant, dry Holstein cows were used. The estrous cycle was synchronized in all cows using CIDR-Ovsynch. Cows were allocated to a control group (n=3) and a fasting group (n=3). In the fasting group, cows were fasted for four days from day -4 to day -1 (day 0=day of 2nd GnRH injection) but otherwise were fed ad libitum. The experiment was repeated in a crossover design after an interval of about one month. The peripheral progesterone (P(4)) concentration in the fasting group was significantly higher than in the control group on day -1 and 0. The peripheral estradiol-17β concentration in the fasting group was also significantly higher than in the control group on day -1 and 0. The portal vein P(4) concentration in the fasting group was significantly higher than in the control group. On day 0, there was no difference in LH secretion between groups. The mean percentages of lipid droplets in liver cells in the fasting group were significantly higher than in the control group on day 0. These results suggest that short-term fasting leads to reduced hepatic steroid hormone metabolism by accumulation of fat in the liver, which causes high peripheral steroid hormone concentrations.     

Larvicidal and adulticidal activity of alkylphthalide derivatives from rhizome of Cnidium officinale against Drosophila melanogaster

The insecticidal activity of the chloroform extract of Cnidium officinale rhizomes and its constituents was investigated against larvae and adults of Drosophila melanogaster and compared with that of rotenone. Bioassay-guided isolation of the chloroform extract of C. officinale resulted in the isolation and characterization of four alkylphthalides, cnidilide (1), (Z)-ligustilide (2), (3S)-butylphthalide (3), and neocnidilide (4). The structures of these compounds were established by spectroscopic analysis. The isolated compounds 2, 3, and 4 exhibited LC50 values of 2.54, 4.99, and 9.90 micromol/mL of diet concentration against larvae of D. melanogaster, respectively. Against both sexes (males/females, 1:1) of adults (5-7 days old), compound 3 showed the most potent activity of the compounds isolated with the LD50 value of 5.93 microg/adult, comparable to that of rotenone (LD50 = 3.68 microg/adult). Structure-activity relationships of phthalides isolated suggest that the presence of conjugation with the carbonyl group in the lactone ring appeared to play an important role in the larvicidal activity. Acetylcholinesterase (prepared from the adult heads of D. melanogaster) inhibitory activity was also investigated in vitro to determine the insecticide mode of action for the acute adulticidal activity.     

Effect of growth hormone on estrogen receptor binding properties in the chick oviduct in vivo

The equilibrium dissociation constant (K_d) and the maximum binding capacity (B_max) of estrogen receptor in cytosolic and nuclear fractions in oviduct of pullets following various daily injections (1–10 times) of growth hormone (GH: 50 µg/chick) were examined by Scathchard analysis of specific [³H]estradiol‐17β (E₂) binding. The K_d values of receptor in both fractions decreased after three times of GH‐injection. In the B_max values, three times of the injection caused a marked decrease in that value in the cytosolic fraction with a concomitant increase in that in the nuclear fraction, whereas the total B_max (sum of B_max in the cytosolic and nuclear fractions) did not change. A similar relationship between the K_d values in the binding of the two fractions was also observed in 4–10 times of GH‐injection. However, in 4–10 times of GH‐injection the B_max of the both fractions and total B_max was greater than that in vehicle‐injection (control). When the chicks were injected with 6–10 times of GH‐injection, the weight of oviduct was increased. No change in the plasma concentrations of E₂ was found following GH‐ and vehicle‐injections into the chicks. The results suggest that growth hormone stimulates the growth of the chick oviduct by increasing the binding affinity and capacity of estrogen receptor.     

PCR-based specific detection of <Emphasis Type="Italic">Ralstonia solanacearum</Emphasis> race 4 strains

Two primer sets were designed based on the sequence of polymorphic bands that were derived from repetitive sequence-based polymerase chain reaction (rep-PCR) fingerprinting and specifically detected in Ralstonia solanacearum race 4 strains (ginger, mioga, and curcuma isolates). One primer set (AKIF-AKIR) amplified a single band (165bp) from genomic DNA obtained from all mioga and curcuma and some ginger isolates; another set (21F-21R) amplified one band (125bp) from the other ginger isolates. These primer sets did not amplify the bands from genomic DNA of other R. solanacearum strains or of other related bacteria. PCR detection limit for the pathogen was 2 × 10²cfu.The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under accession numbers AB118756 and AB118757     

An outbreak of systemic granulomatous disease in cows with high milk yields

Seven of 92 lactating Holstein cows on a dairy farm developed urticaria with alopecia and decreased milk production, and three of the seven died over the course of 7 to 18 days. Pathologic examination of the three cows, including the two dead and one euthanized cow, revealed that the skin, liver, spleen, kidneys, heart, salivary glands, pancreas, adrenal glands, mammary glands, lymph nodes, and trigeminal ganglia had lymphocytic to lymphogranulomatous inflammation. Inflammation predominated by lymphocytic infiltration was prominent in the heart, pancreas, mammary glands, adrenal gland, and trigeminal ganglia. Severe granulomatous inflammation with multinucleated giant cells was present in the spleen and kidneys. These lesions and their distributions were most similar to those seen in suspected cases of citrus pulp toxicosis and hairy vetch toxicosis. The outbreak of this disease resolved with the elimination of Citrus pulp from the feed. Immunohistochemical detection of lymphocytes and macrophage markers confirmed dramatic hyperplasia of CD3-positive T lymphocytes in these lesions. This strongly suggested that a type 4 hypersensitivity reaction played a role in the development of the lesions.     

Cloning of a membrane protein that induces a slow voltage-gated potassium current

A rat kidney messenger RNA that induces a slowly activating, voltage-dependent potassium current on its expression in Xenopus oocytes was identified by combining molecular cloning with an electrophysiological assay. The cloned complementary DNA encodes a novel membrane protein that consists of 130 amino acids with a single putative transmembrane domain. This protein differs from the known ion channel proteins but is involved in the induction of selective permeation of potassium ions by membrane depolarization.