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Embryo transfer as an option to improve fertility in repeat breeder dairy cows Texto completo
2021
Nowicki, Arkadiusz
Embryo transfer as an option to improve fertility in repeat breeder dairy cows Texto completo
2021
Nowicki, Arkadiusz
Repeat breeding is a serious reproductive disorder in dairy cattle. The causes of repeat breeding are multifactorial and there are two main mechanisms: failure of fertilisation or early embryo death, mainly due to poor quality of oocytes and an inadequate uterine environment. Many methods have been used to increase the pregnancy rate for repeat breeder cows, such as intrauterine infusion of antibacterial agents or antibiotics, hormonal treatments for oestrus synchronisation and induction of ovulation, and progesterone supplementation or induction of accessory corpus luteum; however, the results were inconsistent between studies. Embryo transfer (ET) has the capability to minimalise the effects of poor oocyte quality and unfavourable uterine environments on early embryo development during the first seven days after ovulation in repeat breeder cows, and several studies showed that ET significantly improved the pregnancy rate in this group of animals. Thus, ET can be considered an option to increase the conception rate in repeat breeder dairy cows.
Mostrar más [+] Menos [-]Embryo transfer as an option to improve fertility in repeat breeder dairy cows Texto completo
2021
Nowicki Arkadiusz
Repeat breeding is a serious reproductive disorder in dairy cattle. The causes of repeat breeding are multifactorial and there are two main mechanisms: failure of fertilisation or early embryo death, mainly due to poor quality of oocytes and an inadequate uterine environment. Many methods have been used to increase the pregnancy rate for repeat breeder cows, such as intrauterine infusion of antibacterial agents or antibiotics, hormonal treatments for oestrus synchronisation and induction of ovulation, and progesterone supplementation or induction of accessory corpus luteum; however, the results were inconsistent between studies. Embryo transfer (ET) has the capability to minimalise the effects of poor oocyte quality and unfavourable uterine environments on early embryo development during the first seven days after ovulation in repeat breeder cows, and several studies showed that ET significantly improved the pregnancy rate in this group of animals. Thus, ET can be considered an option to increase the conception rate in repeat breeder dairy cows.
Mostrar más [+] Menos [-]Local and systemic influence of toxic levels of airborne ozone on the inflammatory response in rats Texto completo
2021
Chmielewska-Krzesińska, Małgorzata | Wąsowicz, Krzysztof
Local and systemic influence of toxic levels of airborne ozone on the inflammatory response in rats Texto completo
2021
Chmielewska-Krzesińska, Małgorzata | Wąsowicz, Krzysztof
Ozone is not harmful itself; however, it directly oxidises biomolecules and produces radical-dependent cytotoxicity. Exposure to ozone is by inhalation and therefore the lungs develop the main anti-inflammatory response, while ozone has an indirect impact on the other organs. This study investigated the local and systemic effects of the ozone-associated inflammatory response. Three groups each of 5 Wistar Han rats aged 6 months were exposed for 2h to airborne ozone at 0.5 ppm and a fourth identical group were unexposed controls. Sacrifice was at 3h after exposure for control rats and one experimental group and at 24 h and 48 h for the others. Lung and liver samples were evaluated for changes in expression of transforming growth factor beta 1, anti-inflammatory interleukin 10, pro-inflammatory tumour necrosis factor alpha and interleukin 1 beta and two nuclear factor kappa-light-chain-enhancer of B cells subunit genes. Total RNA was isolated from the samples in spin columns and cDNA was synthesised in an RT-PCR. Expression levels were compared to those of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and analysed statistically. All variables changed non-linearly over time comparing experimental groups to the control. Conspicuous expression changes in the subunit genes and cytokines were observed in both evaluated organs. Locally and systemically, inflammation responses to ozone inhalation include regulation of certain genes’ expression. The mechanisms are unalike in lungs and liver but ozone exerts a similar effect in both organs. A broader range of variables influential on ozone response should be studied in the future.
Mostrar más [+] Menos [-]Local and systemic influence of toxic levels of airborne ozone on the inflammatory response in rats Texto completo
2021
Chmielewska-Krzesińska Małgorzata | Wąsowicz Krzysztof
Ozone is not harmful itself; however, it directly oxidises biomolecules and produces radical-dependent cytotoxicity. Exposure to ozone is by inhalation and therefore the lungs develop the main anti-inflammatory response, while ozone has an indirect impact on the other organs. This study investigated the local and systemic effects of the ozone-associated inflammatory response.
Mostrar más [+] Menos [-]Effect of negative energy balance on plasma metabolites, minerals, hormones, cytokines and ovarian follicular growth rate in Holstein dairy cows Texto completo
2021
Song Yuxi | Wang Zhijie | Zhao Chang | Bai Yunlong | Xia Cheng | Xu Chuang
Effect of negative energy balance on plasma metabolites, minerals, hormones, cytokines and ovarian follicular growth rate in Holstein dairy cows Texto completo
2021
Song Yuxi | Wang Zhijie | Zhao Chang | Bai Yunlong | Xia Cheng | Xu Chuang
The aim of this study was to evaluate the effect of negative energy balance (NEB) on the final growth of the dominant ovarian follicle in Holstein cows.
Mostrar más [+] Menos [-]Effect of negative energy balance on plasma metabolites, minerals, hormones, cytokines and ovarian follicular growth rate in Holstein dairy cows Texto completo
2021
The aim of this study was to evaluate the effect of negative energy balance (NEB) on the final growth of the dominant ovarian follicle in Holstein cows. Cows at 14 to 21 d postpartum from an intensive dairy farm were randomly selected and allocated into a positive energy balance group (PEB, with β-hydroxybutyric acid (BHBA) level < 1.2 mmol/L, n = 15) and an NEB group (BHBA > 1.2 mmol/L, n = 15). Plasma samples were collected at 21, 50 and 55 d postpartum to assess the concentrations of energy metabolites, minerals, hormones and cytokines. Ovaries were examined by transrectal ultrasound on days 50 and 55 (120 hours later) to evaluate the diameter of the largest follicle. Compared with PEB cows, there were a more severe body condition loss and a lower milk yield in NEB cows (P < 0.05) and these had greater concentrations of plasma BHBA, non-esterified fatty acids, triglycerides, urea nitrogen, growth hormone, interleukin 6, and fibroblast growth factor 21 and lesser concentrations of plasma glucose, total cholesterol, insulin, insulin-like growth factor 1, insulin-like growth factor binding protein 3, leptin, brain-derived neurotrophic factor and angiopoietin-like protein 8 on d 21 (P < 0.05), while plasma minerals were not affected by energy status (P > 0.05). These changes persisted until the end of the study period (50–55 days postpartum) resulting in a lower follicular growth rate for cows in the NEB than the PEB group. These observations indicate that follicular growth rate is associated with measurable changes in energy metabolite, hormone and cytokine concentrations caused by early postpartum NEB.
Mostrar más [+] Menos [-]Canine leishmaniasis prevalence in the Slovenian dog population Texto completo
2021
Kotnik Tina | Moreno Javier | Šoba Barbara | Krt Brane | Skvarč Miha | Vergles Rataj Aleksandra | Gorišek Bajc Maja | Ravnik Verbič Urša
Canine leishmaniasis prevalence in the Slovenian dog population Texto completo
2021
Kotnik Tina | Moreno Javier | Šoba Barbara | Krt Brane | Skvarč Miha | Vergles Rataj Aleksandra | Gorišek Bajc Maja | Ravnik Verbič Urša
Leishmaniasis is a life-threatening zoonosis of which dogs are the major reservoir and sandflies are the vectors. Until now, the prevalence of canine leishmaniasis (CanL) in the Slovenian dog population was unknown.
Mostrar más [+] Menos [-]Canine leishmaniasis prevalence in the Slovenian dog population Texto completo
2021
Kotnik, Tina | Moreno Lázaro, Javier | Šoba, Barbara | Krt, Brane | Skvarč, Miha | Vergles Rataj, Aleksandra | Gorišek Bajc, Maja | Ravnik Verbič, Urša
Leishmaniasis is a life-threatening zoonosis of which dogs are the major reservoir and sandflies are the vectors. Until now, the prevalence of canine leishmaniasis (CanL) in the Slovenian dog population was unknown. Epidemiological data, eye swabs and blood samples were taken from 465 dogs born in Slovenia and older than one year. Commercial ELISA kits and real-time PCR were used. For ELISA-positive samples, an immunofluorescence antibody test (IFAT) was performed. Descriptive statistics were used to characterise the samples. The one-sample nonparametric chi-square test was used to test whether the categories of a variable were equally distributed. A 59.9% proportion of the recruited dogs had travelled to endemic regions and 62.1% of them had not been protected by insect repellents. Skin symptoms that might be CanL-related were described in 109 of the dogs’ histories (23.4%), inappetence and/or weight loss in 25 (5.4%), and anaemia, intermittent fever, and/or lymphadenopathy in 19 (4.1%). At the time of recruitment, all dogs were asymptomatic. All samples were PCR negative, nine (1.9%) were ELISA positive, but none were IFAT positive. Five of the nine ELISA-positive dogs were non-travellers. We conclude that the seroprevalence of canine leishmaniasis of 1.9 % in the autochthonous Slovenian dog population may pose a risk of endemic spread of the disease.
Mostrar más [+] Menos [-]Effects of tyrosine kinase inhibitor-masitinib mesylate on canine mammary tumour cell lines Texto completo
2021
Ustun-Alkan Fulya | Bakırel Tülay | Üstüner Oya | Anlas Ceren | Cinar Suzan | Yıldırım Funda | Gürel Aydın
Effects of tyrosine kinase inhibitor-masitinib mesylate on canine mammary tumour cell lines Texto completo
2021
Ustun-Alkan Fulya | Bakırel Tülay | Üstüner Oya | Anlas Ceren | Cinar Suzan | Yıldırım Funda | Gürel Aydın
Masitinib mesylate, a selective tyrosine kinase inhibitor of the c-KIT receptor, is used for the treatment of mast cell tumours in dogs. Masitinib has previously been investigated in various cancers; however, its potential anticancer effect in canine mammary tumours (CMTs) is unknown. In the present paper, we investigated the antiproliferative effect of masitinib in CMT cells and its possible mechanisms of action.
Mostrar más [+] Menos [-]Effects of tyrosine kinase inhibitor-masitinib mesylate on canine mammary tumour cell lines Texto completo
2021
Ustun-Alkan, Fulya | Bakırel, Tülay | Üstüner, Oya | Anlas, Ceren | Cinar, Suzan | Yıldırım, Funda | Gürel, Aydın
Masitinib mesylate, a selective tyrosine kinase inhibitor of the c-KIT receptor, is used for the treatment of mast cell tumours in dogs. Masitinib has previously been investigated in various cancers; however, its potential anticancer effect in canine mammary tumours (CMTs) is unknown. In the present paper, we investigated the antiproliferative effect of masitinib in CMT cells and its possible mechanisms of action. The effect of masitinib on the proliferation of CMT-U27 and CMT-U309 cells was assessed by MTT assay and DNA fragmentation. Flow cytometric analysis was used to measure the effect of masitinib on apoptosis and the cell cycle. Additionally, vascular endothelial growth factor levels (VEGF) were measured, and the proliferation marker Ki-67 was visualised in immunocytochemical stainings in CMT cells. Treatment with masitinib inhibited the proliferation of CMT cells in a concentration-dependent manner. Maximal apoptotic activity and DNA fragmentation were observed at approximately IC₅₀ of masitinib in both cell lines. In addition, cell cycle distribution was altered and VEGF levels and Ki-67 proliferation indices were decreased in masitinib-treated cells in comparison with control cells. In this study, masitinib suppressed cell proliferation concomitantly via induction of apoptosis and cell cycle arrest by decreasing VEGF levels and the Ki-67 proliferation index in CMT-U27 and CMT-U309 cells in vitro, suggesting its potential as a therapeutic tool in the clinical setting of mammary cancer treatment in dogs.
Mostrar más [+] Menos [-]Antioxidant status, and blood zinc and copper concentrations in dogs with uncomplicated babesiosis due to Babesia canis infections Texto completo
2021
Teodorowski Oliwier | Winiarczyk Stanisław | Tarhan Duygu | Dokuzeylül Banu | Ercan Alev Meltem | Or Mehmet Erman | Staniec Marta | Adaszek Łukasz
Antioxidant status, and blood zinc and copper concentrations in dogs with uncomplicated babesiosis due to Babesia canis infections Texto completo
2021
Teodorowski Oliwier | Winiarczyk Stanisław | Tarhan Duygu | Dokuzeylül Banu | Ercan Alev Meltem | Or Mehmet Erman | Staniec Marta | Adaszek Łukasz
The aim of the study was to demonstrate a link between uncomplicated Babesia canis infection in dogs and blood concentrations of zinc and copper and erythrocytic antioxidant defence – activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT).
Mostrar más [+] Menos [-]Antioxidant status, and blood zinc and copper concentrations in dogs with uncomplicated babesiosis due to Babesia canis infections Texto completo
2021
Teodorowski, Oliwier | Winiarczyk, Stanisław | Tarhan, Duygu | Dokuzeylül, Banu | Ercan, Alev Meltem | Or, Mehmet Erman | Staniec, Marta | Adaszek, Łukasz
The aim of the study was to demonstrate a link between uncomplicated Babesia canis infection in dogs and blood concentrations of zinc and copper and erythrocytic antioxidant defence – activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The study was based on 15 naturally occurring cases of canine babesiosis with anorexia, pyrexia, depression, pale mucous membrane, splenomegaly and dark red urine. Microscopic examination of Giemsa-stained peripheral blood smears and the results of PCR confirmed B. canis infection. Seven apparently healthy dogs brought in for either a check-up or vaccination were used for comparison. The levels of the erythrocytic antioxidant enzymes - SOD and CAT - were significantly higher in the infected dogs than in cytologically negative dogs. The levels of blood micronutrients were significantly lower in the infected dogs (0.478 μg of zinc per mL vs 1.241 μg/mL and 0.722 μg of copper per mL vs 1.392 μg/mL). Oxidative stress can be posited as one of the mechanisms leading to anaemia in dogs with babesiosis, and therefore antioxidant biomarker and copper and zinc concentrations could be used as indicators of disease severity and prognostic markers.
Mostrar más [+] Menos [-]The preventive role of Spirulina platensis (Arthrospira platensis) in immune and oxidative insults in a stress-induced rat model Texto completo
2021
Seyidoğlu Nilay | Köşeli Eda | Gurbanlı Rovshan | Aydın Cenk
The preventive role of Spirulina platensis (Arthrospira platensis) in immune and oxidative insults in a stress-induced rat model Texto completo
2021
Seyidoğlu Nilay | Köşeli Eda | Gurbanlı Rovshan | Aydın Cenk
There is a balance between oxidative stress, antioxidant capacity and immune response. Their roles in physiological and behavioural mechanisms are important for the maintenance of the organism’s internal equilibrium. This study aimed to evaluate the antioxidant effects of the exogenous alga Spirulina platensis (Arthrospira platensis) in a stress-induced rat model, and to describe its possible mechanism of action.
Mostrar más [+] Menos [-]The preventive role of Spirulina platensis (Arthrospira platensis) in immune and oxidative insults in a stress-induced rat model Texto completo
2021
Seyidoğlu, Nilay | Köşeli, Eda | Gurbanlı, Rovshan | Aydın, Cenk
There is a balance between oxidative stress, antioxidant capacity and immune response. Their roles in physiological and behavioural mechanisms are important for the maintenance of the organism’s internal equilibrium. This study aimed to evaluate the antioxidant effects of the exogenous alga Spirulina platensis (Arthrospira platensis) in a stress-induced rat model, and to describe its possible mechanism of action. Thirty-six adult male Sprague Dawley rats were separated into four groups: control (C), stress (S), S. platensis (Sp), and S. platensis + stress (SpS). The rats in groups Sp and SpS were fed with 1,500 mg/kg b.w./day Spirulina platensis for 28 days. All rats were exposed to prolonged light phase conditions (18 h light : 6 h dark) for 14 days. The SpS and S groups were exposed to stress by being kept isolated and in a crowded environment. Blood samples were obtained by puncturing the heart on the 28th day. The effect of stress on serum corticosterone, oxidative stress markers (TOS, TAC, PON1, OSI) and immunological parameters (IL-2, IL-4, IFN-ɣ) were tested. Also, the brain, heart, intestines (duodenum, ileum, and colon), kidney, liver, spleen, and stomach of the rats were weighed. Serum corticosterone levels were higher in the S group than in the C group, and significantly lower in the SpS group than in the S group. Mean total antioxidant capacity were lower in the S group than in the C group, and Spirulina reversed this change. Although not significantly different, IL-2 was lower in the S group than in the C group. However, in the SpS group, IL-2 increased due to Spirulina platensis mitigating effects of stress. Male rats fed a diet with Spirulina platensis could experience significantly milder physiological changes during stress, although stress patterns may be different. Exogenous antioxidant supplements merit further investigation in animals and humans where the endogenous defence mechanism against stress may not be sufficient.
Mostrar más [+] Menos [-]Assessment of the morphometry of heads of normal sperm and sperm with the Dag defect in the semen of Duroc boars Texto completo
2021
Banaszewska Dorota | Andraszek Katarzyna
Assessment of the morphometry of heads of normal sperm and sperm with the Dag defect in the semen of Duroc boars Texto completo
2021
Banaszewska Dorota | Andraszek Katarzyna
The Dag defect is one of the primary morphological defects in sperm correlating with reduced fertility. This defect is found in the spermatozoa of many livestock species. The aim of the study was to assess the morphometry of the heads of normal sperm and sperm with the Dag defect in the semen of Duroc breeding boars.
Mostrar más [+] Menos [-]Assessment of the morphometry of heads of normal sperm and sperm with the Dag defect in the semen of Duroc boars Texto completo
2021
Banaszewska, Dorota | Andraszek, Katarzyna
The Dag defect is one of the primary morphological defects in sperm correlating with reduced fertility. This defect is found in the spermatozoa of many livestock species. The aim of the study was to assess the morphometry of the heads of normal sperm and sperm with the Dag defect in the semen of Duroc breeding boars. Sperm morphology was examined in ten ejaculates each from 12 Duroc boars. In total, 3,600 morphologically normal sperm and 838 sperm with the Dag defect were evaluated. The area, perimeter, length and width of the sperm head were measured and these basic morphometric parameters were used to calculate four additional shape indices characterising the sperm head, i.e. ellipticity, elongation, roughness and regularity. Sperm with this defect had markedly smaller heads, 0.32 μm shorter and 0.19 μm narrower than the heads of sperm with normal morphological structure. The heads of sperm with the Dag defect also had a 1.1μm smaller perimeter and a 2.5 μm² smaller surface area than the heads of morphologically normal sperm. The Dag defect is found in boar sperm irrespective of the age of the individual. It affects the morphology of the sperm head.
Mostrar más [+] Menos [-]In vivo study of the oestrogenic activity of milk Texto completo
2021
Radko Lidia | Posyniak Andrzej
In vivo study of the oestrogenic activity of milk Texto completo
2021
Radko Lidia | Posyniak Andrzej
Milk has been suggested to be a possible source of oestrogenically active compounds. In order to assess the health risk for milk consumers and ensure the safety of this staple part of the human diet, it is important to study the effect of xenooestrogen mixtures present in milk. This investigation used the available in vivo model to learn to what extent such compounds may be endocrine disruptors.
Mostrar más [+] Menos [-]In vivo study of the oestrogenic activity of milk Texto completo
2021
Radko, Lidia | Posyniak, Andrzej
Milk has been suggested to be a possible source of oestrogenically active compounds. In order to assess the health risk for milk consumers and ensure the safety of this staple part of the human diet, it is important to study the effect of xenooestrogen mixtures present in milk. This investigation used the available in vivo model to learn to what extent such compounds may be endocrine disruptors. The recommended immature golden hamster uterotrophic bioassay was chosen. A total of 132 animals were divided into nine groups of experimental animals and positive and negative control groups, each of 12 animals. The experimental females received ad libitum either one of five samples of raw cow’s milk from individual animals or one of four samples of pasteurised or ultra-high temperature treated cow’s milk as retail products. After 7 days, the animals were sacrificed and necropsied. Uterine weight increases were measured as the endpoint of oestrogenic activity in milk. The milk samples from individual cows and the retail milk samples did not show oestrogenic activity. However, in three groups, decreased uterine weights were observed. Considering that milk supplies are beneficial to health, contamination in this food should be avoided. There is a need for further animal experiments and epidemiological studies are warranted to evaluate any causative role of milk in human endocrinological disorders.
Mostrar más [+] Menos [-]Evaluation of oxidative stress parameters in dogs with brachycephalic obstructive airway syndrome before and after surgery Texto completo
2021
Erjavec Vladimira | Vovk Tomaž | Svete Alenka Nemec
Evaluation of oxidative stress parameters in dogs with brachycephalic obstructive airway syndrome before and after surgery Texto completo
2021
Erjavec Vladimira | Vovk Tomaž | Svete Alenka Nemec
Canine brachycephalic obstructive airway syndrome (BOAS) is a conformation-related respiratory disorder of dog breeds having congenitally flattened facial and skull anatomy. The aim of the study was to determine oxidative stress parameters, the lipid peroxidation product malondialdehyde, and antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase in BOAS patients before and after surgical treatment and in healthy brachycephalic dogs.
Mostrar más [+] Menos [-]Evaluation of oxidative stress parameters in dogs with brachycephalic obstructive airway syndrome before and after surgery Texto completo
2021
Erjavec, Vladimira | Vovk, Tomaž | Svete, Alenka Nemec
Canine brachycephalic obstructive airway syndrome (BOAS) is a conformation-related respiratory disorder of dog breeds having congenitally flattened facial and skull anatomy. The aim of the study was to determine oxidative stress parameters, the lipid peroxidation product malondialdehyde, and antioxidant enzymes superoxide dismutase (SOD) and glutathione peroxidase in BOAS patients before and after surgical treatment and in healthy brachycephalic dogs. Nine healthy brachycephalic dogs that had not undergone surgery and 39 BOAS patients were included in the study. The BOAS patients were classified as grade 1 (5/34), grade 2 (16/34), and grade 3 (13/34) based on the decrease in the radius of the airway in the larynx. In BOAS patients, oxidative stress parameters were determined before and two weeks after surgery, while in control dogs, blood samples were collected only on inclusion to the study. All BOAS patients showed various degrees of improvement in clinical signs after surgery. Significantly lower (P < 0.05) SOD activity was found in grade 2 and 3 BOAS patients than in grade 1 patients. Two weeks after surgery, a significant (P < 0.05) increase in SOD activity in grade 2 and 3 patients was observed. Antioxidant enzyme SOD may play an important role in BOAS and can be used as a biomarker of antioxidant status assessment in BOAS patients.
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