A case study of improving milking cow performance and milking system performance with using a flow simulator

Efforts to improve dairy performance have been focused on increasing milk productivity of cows through improved feeding systems and genetic potential. However, methods for evaluating milking system performance based on milk productivity have not yet been established. Milking system performance was evaluated by measuring the claw vacuum at five flow rates (1.9–8.7 kg/min) produced using a flow simulator for a single eight‐swing milking parlor with a high‐line system. Based on these results, a double eight‐parallel milking parlor with a low‐line system was installed and tested. Farmers can take data obtained from evaluations of milking system performance into account for future management decisions, such as renewing the milking system. By renewing the milking system, average milking productivity, somatic cell linear score (LS) of bulk milk, and LS of each cow were significantly improved in the year after installing the new system (p < .01). In addition to checking conventional milking systems, this novel diagnostic method using a flow simulator can be used for checking new installations and also for proposing renovations.     

A Study on the Presence of Ferritin-binding Proteins in Fetal Horse Plasma

In mammal circulation, ferritin-binding proteins (FBPs) are thought to be involved in clearance of circulating ferritin after complex formation with it through receptor-mediated uptake. However, there is no report on fetal FBP in fetal circulation. Although iron concentrations of fetal horse plasma were higher than those of adult horse plasma, plasma ferritin concentrations and ferritin-binding activities were found to be significantly lower in fetus than in adult. FBPs were purified from fetal or adult horse plasma on horse spleen ferritin-Sepharose 4B affinity column. Partially affinity-purified fetal horse plasma FBPs were mainly separated into 65 and 41 kDa bands in addition to minor bands with higher molecular masses ranged from 102 to 140 kDa on SDS-PAGE under reducing condition. The adult horse plasma FBPs were separated into 74, 54 and 28 kDa bands, and the 74 and 54 kDa bands reacted with antibodies specific for horse IgM and IgG heavy chains, respectively, by immunoblotting analyses. On the other hand, no antibodies to horse immunoglobulin classes detected any bands in fetal horse plasma FBPs. The affinity-purified adult and fetal horse plasma FBPs did not contain fibrinogen as a plasma specific FBP, probably due to its lower affinity to the ligand ferritin. These results demonstrate the presence of FBPs which are different from adult horse plasma FBPs including anti-ferritin autoantibodies in fetal plasma.     

Immunohistochemical localization of three GnRH systems in brain and pituitary of Japanese flounder

ABSTRACT:   To clarify the possible roles of gonadotropin-releasing hormone (GnRH) in the reproduction of Japanese flounder Paralichthys olivaceus , localization of salmon GnRH (sGnRH), chicken GnRH-II (cGnRH-II), and sea bream GnRH (sbGnRH) immunoreactive (ir) cell bodies and fibers in the brain and pituitary were examined together with follicle stimulating hormone (FSH) and luteinizing hormone (LH)-ir cells in the pituitary by immunohistochemistry. sGnRH-ir cell bodies were localized in the ventromedial part of the rostral olfactory bulb and cGnRH-II-ir cell bodies were restricted to the midbrain tegmentum, while sbGnRH-ir cell bodies were evident in the preoptic area. sGnRH-ir fibers were distributed throughout the brain, especially abundant in the forebrain. cGnRH-II-ir fibers were also scattered in many areas of the brain with abundance in the midbrain, but sbGnRH-ir fibers were observed in the preoptic–hypothalamic area and innervated the pituitary. In the pituitary, neither sGnRH-ir fibers nor cGnRH-II-ir fibers were found, but sbGnRH-ir fibers were profuse in the neurohypophysis and invaded the proximal pars distalis, targeting FSH and LH cells. These results suggest that three GnRH systems can play different physiological roles in the brain of Japanese flounder. Among them, sbGnRH is considered to be involved in reproduction by stimulating gonadotropin secretion, while sGnRH and cGnRH-II can function as a neurotransmitter and/or neuromodulator within the brain in this species.     

Changes in brain and pituitary GnRH levels during ovarian maturation in wild female Japanese flounder

To elucidate the role of gonadotropin-releasing hormone (GnRH) in gonadal maturation in wild female Japanese flounder Paralichthys olivaceus, we monitored changes in the levels of seabream GnRH (sbGnRH) in the olfactory bulb, telencephalon, hypothalamus, and pituitary during ovarian development together with changes in plasma levels of testosterone (T), estradiol-17β (E₂), and 17α, 20β-dihydroxy-4-pregnen-3-one (DHP). Fish were caught offshore of the northern mainland of Japan in the Pacific Ocean at 3- to 4-week intervals between April and September by gill net. The netted fish were categorized into six groups based on ovarian stages: previtellogenic (April–early May), early yolk (April–late May), late yolk (late May–June), early spawning (June–August), late spawning (September), and termination (September) stages. The gonadosomatic index significantly increased from the previtellogenic to early spawning stages and decreased thereafter. In the olfactory bulb, no significant differences were observed in sbGnRH levels among the developmental stages. In contrast, sbGnRH levels in the telencephalon and hypothalamus were very high in the previtellogenic stage, lower in the early spawning stage, and relatively high in latter stages. sbGnRH levels in the pituitary were high in the previtellogenic stage and low in the early spawning stage. In addition, the relatively high levels of pituitary sbGnRH were found together with high plasma T, E₂, and DHP levels in fish in the late yolk stage. These results indicate that sbGnRH in the telencephalon, hypothalamus, and pituitary is involved in ovarian maturation and that sbGnRH may play an important role in the initiation of ovarian recrudescence in wild Japanese flounder.     

Structure and Steroidogenesis of the Placenta in the Antarctic Minke Whale (Balaenoptera bonaerensis)

There are few reports describing the structure and function of the whale placenta with the advance of pregnancy. In this study, therefore, the placenta and nonpregnant uterus of the Antarctic minke whale were observed morphologically and immunohistochemically. Placentas and nonpregnant uteri were collected from the 15th, 16th and 18th Japanese Whale Research Programme with Special Permit in the Antarctic (JARPA) and 1st JARPA II organized by the Institute of Cetacean Research in Tokyo, Japan. In the macro- and microscopic observations, the placenta of the Antarctic minke whale was a diffuse and epitheliochorial placenta. The chorion was interdigitated to the endometrium by primary, secondary and tertiary villi, which contained no specialized trophoblast cells such as binucleate cells, and the interdigitation became complicated with the progress of gestation. Furthermore, fetal and maternal blood vessels indented deeply into the trophoblast cells and endometrial epithelium respectively with fetal growth. The minke whale placenta showed a fold-like shape as opposed to a finger-like shape. In both nonpregnant and pregnant uteri, many uterine glands were distributed. The uterine glands in the superficial layer of the pregnant endometrium had a wide lumen and large epithelial cells as compared with those in the deep layer. On the other hand, in the nonpregnant endometrium, the uterine glands had a narrower lumen and smaller epithelial cells than in the pregnant endometrium. In immunohistochemical detection, immunoreactivity for P450scc was detected in most trophoblast cells, but not in nonpregnant uteri, suggesting that trophoblast epithelial cells synthesized and secreted the sex steroid hormones and/or their precursors to maintain the pregnancy in the Antarctic minke whale.     

A single gene transfer of gibberellin biosynthesis gene cluster increases gibberellin production in a Fusarium fujikuroi strain with gibberellin low producibility

Fusarium fujikuroi, the causative agent of bakanae disease in rice, produces many kinds of secondary metabolites. Recently, two phylogenetic subgroups (F and G groups) of Japanese F. fujikuroi have been identified and found to have differences in their gibberellin (GA) and fumonisin production. G-group F. fujikuroi produces large amounts of GA, but is a fumonisin nonproducer. F-group produces large amounts of fumonisin, but is a GA low or nonproducer. We investigated the cause of low GA production in the F-group. Genetic mapping suggests that low GA production in the F-group strain Gfc0825009 is due to a GA gene cluster for GA biosynthesis. Analysis of the nucleotide and amino acid sequences of the genes in the GA gene cluster showed >98.4% homology between the F-group strain Gfc0825009 and the G-group strain Gfc0801001. Following a 7-day culture under low nitrogen conditions, we found that expression of P450-1, P450-4, and P450-2 in the cluster increased in the G-group strain and not in the F-group strain. We hypothesized that complementation by GA genes in the G-group strain would be required to increase GA production in the F-group strain. However, we found that this occurred with a single gene complementation of DES, P450-1, P450-4, or P450-2. Simultaneous increase in the expression of P450-1, P450-4, and P450-2 were detected in the complementary transformants. Moreover, the same phenomenon was observed by reintegration of its own P450-1. Our results suggest the presence of unknown regulatory mechanisms of the GA gene cluster in F. fujikuroi.     

Low-dose recombinant canine interferon-γ for treatment of canine atopic dermatitis: An open randomized comparative trial of two doses

The purpose of this study was to investigate the minimum effective dose of recombinant canine interferon-γ (rCaIFN-γ) for the treatment of dogs with atopic dermatitis (AD). Thirty-four dogs with AD from 17 animal hospitals in Japan were administered half or one-fifth of the approved rCaIFN-γ dose of 10 000 units/kg, three times a week for 4 weeks, followed by once weekly for an additional 4 weeks. Pruritus, excoriation, erythema and alopecia were evaluated and scored by the investigators on weeks 2, 4, 6, 8 and 12. The efficacy rate (number of excellent cases + number of good cases/total number of cases) at week 8 in the 2000 units/kg group was 36.4% for pruritus, 36.4% for excoriation, 45.5% for erythema and 36.4% for alopecia. In contrast, in the 5000 units/kg group, the efficacy rate was 64.3% for pruritus, 57.1% for excoriation, 78.6% for erythema and 78.6% for alopecia. The efficacy rate of the 5000 units/kg group was high for all signs evaluated and comparable to that of the 10 000 units/kg group reported in a previous study. The results of this study showed that 2000 units/kg of rCaIFN-γ is less effective than 5000 units/kg to treat dogs with AD, and the efficacy of the 5000 units/kg dose is comparable to that of 10 000 units/kg at week 8.     

Characterization of the D/C mosaic neurotoxin produced by Clostridium botulinum associated with bovine botulism in Japan

Clostridium botulinum types C and D are related to avian and mammalian botulism. Bovine botulism occurred at various farms from 2004 to 2007 in Japan. Since culture supernatants of isolates from cases of bovine botulism were neutralized completely and partially with type D and C antitoxins, respectively, we attempted to confirm the nucleotide sequences of the neurotoxin gene in isolates. The neurotoxin gene comprised two-thirds of the type D neurotoxin gene and one-third of the type C neurotoxin gene, indicating that the neurotoxin of bovine isolates is a mosaic of type D and C neurotoxins, D/C mosaic neurotoxin. We prepared four sets of primers to differentiate the genes of the mosaic and authentic forms with PCR. The results showed that all bovine botulism-related isolates possess the gene for the D/C mosaic form. Pulsed-field gel electrophoresis analysis demonstrated that isolates from bovine botulism which had occurred between 2004 and 2007 were genetically homologous, except for the isolate from one area. We further examined the biological and antigenic properties of the D/C mosaic neurotoxin, which was found to exhibit the highest lethal activity in mice compared with other types of neurotoxins. In the D/C mosaic neurotoxin, three epitopes recognized by monoclonal antibodies that specifically react to and neutralize the toxin were located in the carboxyl-terminal domain of the heavy chain. These results indicate that D/C mosaic neurotoxin is a pathogenic agent causing bovine botulism and has unique characteristics different from other type C and D neurotoxins.     

Involvement of sex steroids,luteinizing hormone and thyroid hormones in upstream and downstream swimming behavior of land-locked sockeye salmon <Emphasis Type="Italic">Oncorhynchus nerka</Emphasis>

The involvement of testosterone (T), estradiol-17β (E₂), 11-ketotestosterone (11-KT), 17,20β-dihydroxy-4-pregnene-3-one (DHP), luteinizing hormone (LH), thyroxine (T₄), and triiodothyronine (T₃) in the regulation of downstream and upstream movement (swimming behavior) was investigated in land-locked sockeye salmon Oncorhynchus nerka, using an artificial raceway. During the downstream migratory period, T implant resulted in high plasma T levels and inhibited the occurrence of downstream swimming behavior (negative rheotaxis) in yearling (1+) immature smolts. In terms of upstream behavior, 2-year-old (2+) males exhibited high plasma T and 11-KT levels, while 2+ females had elevated T and DHP levels. In 1+ immature fish, a T implant induced upstream swimming behavior (positive rheotaxis). In experiments 1 and 3, the plasma T₄ and T₃ levels of non-migrants tended to be higher than those of migrants. In contrast, no marked changes in plasma and pituitary LH were found in both downstream and upstream migrants. These results suggest that sex steroids, such as T, play significant roles in the regulation of downstream and upstream swimming behaviors in land-locked sockeye salmon.