• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.570-575
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• 2002

Effects of active immunization against native 14-mer somatostatin (SRIF, somatotropin releasing inhibiting factor) and its two 14-mer-somatostatin analogues on the milk production in rat mammary cells were studied. Native SRIF, Tyr11-somatostatin (Tyr11-SRIF), and D-Trp8, D-Cys14-somatostatin (Trp8Cys14-SRIF) were conjugated to bovine serum albumin (BSA) for immunogen preparation. Twenty-four female Sprague-Dawley rats were divided into four groups and immunized against saline (Control), SRIF, Tyr11-SRIF, and Trp8Cys14-SRIF at five weeks of age. Booster immunizations were performed at 7, 9, and 11 weeks of age. SRIFimmunized rats were mated at 10 weeks of age. The blood and mammary glands were collected at day 15 post-pregnancy and -lactation. To measure the amount of milk protein synthesis in the mammary gland, mammary cells isolated from the pregnant and the lactating rats, were cultured in the presence of $^3H$-lysine. No significant differences in growth performance, concentration of growth hormone in the circulation, and the amount of milk protein synthesis were observed among the groups. Inductive levels of serum anti-SRIF antibody in the SRIF and Tyr11-SRIF groups but not in the Trp8Cys14-SRIF group, were significantly higher than that of the control group during the pregnancy and lactation periods. The result suggests that active immunization against native 14-mer SRIF and Tyr11-SRIF was able to induce anti-SRIF antibodies, but did not affect the milk protein synthesis.

• Journal of Veterinary Clinics
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• v.27 no.3
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• pp.246-251
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• 2010

Mastitis is an inflammation of the mammary gland that develops as a response to pathogenic microorganisms. Somatic cell count (SCC) and bacteriological analysis are the most accepted tools to determine udder health. This study evaluated the effects of intra-mammary gland infusion of silver ion against clinical mastitis in Holstein cows. Silver ion (20 ${\mu}g$/ml) was infused through the intra-mammary gland in quarters having clinical mastitis and milk was collected to determine SCC, and levels of lactoferrin and bovine serum albumin (BSA). Silver ion infusion decreased udder inflammation, firmness and swelling, and reduced clots, BSA, lactoferrin and SCC in milk. However, milk yield and circulating blood cells remained unchanged. The silver ion-mediated reductions of BSA and SCC indicate reduced inflammation and bacterial activity in silver ion-treated mammary glands in Holsteins with mastitis, which may be exploited in a curative strategy.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.11
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• pp.1699-1713
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• 2020

Bovine mastitis, an inflammation of the mammary gland, is the most common disease of dairy cattle causing economic losses due to reduced yield and poor quality of milk. The etiological agents include a variety of gram-positive and gram-negative bacteria, and can be either contagious (e.g., Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma spp.) or environmental (e.g., Escherichia coli, Enterococcus spp., coagulase-negative Staphylococcus, Streptococcus uberis). Improving sanitation such as enhanced milking hygiene, implementation of post-milking teat disinfection, maintenance of milking machines are general measures to prevent new cases of mastitis, but treatment of active mastitis infection is dependant mainly on antibiotics. However, the extensive use of antibiotics increased concerns about emergence of antibiotic-resistant pathogens and that led the dairy industries to reduce the use of antibiotics. Therefore, alternative therapies for prevention and treatment of bovine mastitis, particularly natural products from plants and animals, have been sought. This review provides an overview of bovine mastitis in the aspects of risk factors, control and treatments, and emerging therapeutic alternatives in the control of bovine mastitis.

• Molecules and Cells
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• v.39 no.5
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• pp.410-417
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• 2016

During the lactation cycle of the bovine mammary gland, autophagy is induced in bovine mammary epithelial cells (BMECs) as a cellular homeostasis and survival mechanism. Interferon gamma ($IFN-{\gamma}$) is an important antiproliferative and apoptogenic factor that has been shown to induce autophagy in multiple cell lines in vitro. However, it remains unclear whether $IFN-{\gamma}$ can induce autophagy and whether autophagy affects milk synthesis in BMECs. To understand whether $IFN-{\gamma}$ affects milk synthesis, we isolated and purified primary BMECs and investigated the effect of $IFN-{\gamma}$ on milk synthesis in primary BMECs in vitro. The results showed that $IFN-{\gamma}$ significantly inhibits milk synthesis and that autophagy was clearly induced in primary BMECs in vitro within 24 h. Interestingly, autophagy was observed following $IFN-{\gamma}$ treatment, and the inhibition of autophagy can improve milk protein and milk fat synthesis. Conversely, upregulation of autophagy decreased milk synthesis. Furthermore, mechanistic analysis confirmed that $IFN-{\gamma}$ mediated autophagy by depleting arginine and inhibiting the general control nonderepressible-2 kinase (GCN2)/eukaryotic initiation factor $2{\alpha}$ ($eIF2{\alpha}$) signaling pathway in BMECs. Then, it was found that arginine supplementation could attenuate $IFN-{\gamma}$-induced autophagy and recover milk synthesis to some extent. These findings may not only provide a novel measure for preventing the $IFN-{\gamma}$-induced decrease in milk quality but also a useful therapeutic approach for $IFN-{\gamma}$-associated breast diseases in other animals and humans.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.214-214
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• 2004

Follicle stimulating hormone (FSH) is a pituitary glycoprotein composed of two post translationally modified subunits, which must properly assemble to be biologically active. We developed a transgenic (TG) mouse model that overexpresses the human Follicle-Stimulating hormone (FSH) -subunit under the bovine -casein promoter, displaying in females an excessive levels express in mammary gland. (omitted)

• Korean Journal of Animal Reproduction
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• v.20 no.4
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• pp.371-378
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• 1997

Human lactoferrin (hLF) was expressed in the mammary gland of transgenic mice. Expresion of hLF was achieved by palcing its cDNA under the control of bovine $\beta$-casein gene. To improve the hLF expression level, two artificial introns were introduced into the expression vector. One intron is a hybrid-splice consisting of bovine $\beta$ casein intron 1 and rabbit $\beta$-casem intron II. The other intron is a DNA fragment spanning intron 8 of bovine $\beta$ casein gene. Trans sgenic mice were developed which expressed hLF in their milk. Twenty lines of transgenic mice were produced. hLF was present in the milk at concentrations of 1 ~ 200 ${\mu}\textrm{g}$ / ml. hLF RNA was only detected in the mammary gland of transgenic mice. The expressed RNA was cor r rectly spliced at the exon /intron junctions. To generate transgenic cows secreting active hLF in their milk, we transferred the DNA-injected bovine embryos to recipient heifers by surgical a and non-surgical methods out of 68 embryos transferred to 51 recipients by surgical or non-surgical method, 7 calves were normally born. Effect of embryo quality of DNA-injected blastocysts on pregnancy rate after transfer was investig a ated. Higher pregnancy rate of (38.9%) DNA-injected embryos was shown in excellent embryos. Pregnancy rates in the groups of good a and fair embryos were 15.4 and 14.3%, respectively. Effect of culture period of DNA-injected b bovine embryos on pregnancy rate after transfer was investigated. When Day-6 blastocysts of cuI ture were transferred, there was no pregnancy. Pregnancy rates of Day-7 and -8 blastocysts were 28.6 and 33.3%, respectively. There was no difference on pregnancy rate between Day-7 a and -8 bovine blastocysts after DNA injection. Thus, we established the techniques for transfer a and culture of DNA-injected bovine embryos. In a addition, factors affecting the pregnancy rate of DNA-injected embryos after transfer were investigated .

• Journal of Veterinary Clinics
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• v.3 no.1
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• pp.277-298
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• 1986

This paper reviews the mechanisms effecting host defense in the mammary gland and assesses their possible in preventing of bovine mastitis. The streak canal is the first line of defense against invading mastitis pathogens, providing a physical barrier and antibacterial substances. The milk leukocytes are a second defense line by ingesting pathogens breached the streak canal by multiplication, physical passage, and propulsion during milking. Leukocytosis in milk and enhancement of the phagocytic defense machanisms of the udder were accomplished by inserting intramammary devices. Milk antibodies serum derived and synthesized in mamma tissue aggregate and opsonise bacteria, agglutinate and neutralise toxins, and inhibit. binding of bacteria to epitherial surfaces. Vaccination generally has been unsuccessful because protection is not absolute, but immunization is useful in controlling specific pathogens. Immunostimulant to enhance locally the protective nature of antibody-producing plasma cells concentrated in internal teat end tissue may be effective in reducing the occurrence of infection, but ineffective in preventing intramammary infections.

• Reproductive and Developmental Biology
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• v.41 no.3
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• pp.51-55
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• 2017

The production of therapeutic protein from transgenic domestic animal is the major technology of biotechnology. Insulin-like growth factor-1 (IGF-1) is known to play an important role in the growth of the animal. The objective of this study is construction of knock-in vector that bovine IGF-1 gene is inserted into the exon 7 locus of ${\beta}$-casein gene and expressed using the gene regulatory DNA sequence of bovine ${\beta}$-casein gene. The knock-in vector consists of 5' arm region (1.02 kb), bIGF-1 cDNA, CMV-EGFP, and 3' arm region (1.81 kb). To express bIGF-1 gene as transgene, the F2A sequence was fused to the 5' terminal of bIGF-1 gene and inserted into exon 7 of the ${\beta}$-casein gene. As a result, the knock-in vector is confirmed that the amino acids are synthesized without termination from the ${\beta}$-casein exon 7 region to the bIGF-1 gene by DNA sequence. These knock-in vectors may help to create transgenic dairy cattle expressing bovine bIGF-1 protein in the mammary gland via the expression system of the bovine ${\beta}$-casein gene.

• Reproductive and Developmental Biology
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• v.29 no.4
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• pp.235-239
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• 2005

This study was conducted to test whether the transgenic cattle pass the transgene to their progeny through germ cells, and whether the transgene is expressed in the mammary gland of ransgenic cows. Two male ransgenic calves were born from IVF-derived embryos injected with bovine $\beta-casein/human$ lactoferrin fusion gene and then grew up to be reproducible. Semen was collected from a transgenic bull after 18 mon of age and then frozen. Bovine oocytes matured in vitro were fertilized with spermatozoa of the transgenic bull and cultured in $50\;{\mu}L$ drops of CRlaa medium supplemented with 3 mg/mL BSA. After 48 h of culture, cleaved embryos were determined for the presence of transgenes by DNA polymerase chain reaction (PCR). Proportion of transgene positives among bovine embryos fertilized with sperm of the transgenic bull was $20.9\%$ (28/134). One of transgenic bulls did not produce transgenic sperm. Out of 34 calves produced from recipient heifers inseminated with semen of the other bull, 3 $(8.8\%)$ were transgenic animals (2 females and 1 male). Thus, one transgenic bull showed a low transmission frequency below Mendelian levels in both the IVF-derived embryos and his progeny. It was demonstrated by Southern blot that copy numbers of the transgene in the transgenic progeny enhanced about 1.8 times as compared to those of the founder bull The results demonstrate that the transgenic bull carrying human lactoferrin gene could pass his transgene to the progeny through germ cells, although he is a germ-line mosaic.

• Journal of Animal Science and Technology
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• v.61 no.2
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• pp.61-68
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• 2019

The hG-CSF (human Granulocyte Colony-Stimulating Factor) is a growth and stimulation factor capable of inducing the proliferation of bone marrow cells, several types of leukocytes, among other hematopoietic tissue cells. hG-CSF is used in used to treat anomalies that reder a small number of circulating white blood cells, which may compromise the immune defenses of the affected person. For these reasons, the production of hG-CSF in a bioreactor system using the mammary gland of genetic modified animals is a possibility of adding value to the bovine genetic material and reducing the costs of hG-CSF production in pharmaceutical industry. In this study, we aimed the production of transgenic hG-CSF bovine through the lipofection of bovine primary fibroblasts with an hG-CSF expression cassette and cloning these fibroblasts by the somatic cell nuclear transfer (SCNT) technique. The bovine fibroblasts transfected with the hG-CSF cassette presented a stable insertion of this construct into their genome and were efficiently synchronized to G0/G1 cell cycle stage. The transgenic fibroblasts were cloned by SCNT and produced 103 transferred embryos and 2 pregnancies, one of which reached 7 months of gestation.