Ottó Szenci - Academia.edu (original) (raw)
Papers by Ottó Szenci
Reproduction in Domestic Animals, 2007
This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune... more This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune sheep during early pregnancy. Measurements were performed by using semipurified ovPAG as standard, tracer and immunogens for antibody production in rabbits. Antisera R780 (against ovPAG 57+59kDa) and R805 (against ovPAG5 58+61kDa) were used respectively in RIA-780 and RIA-805. Blood samples were collected at days 0, 18, 20, 22 and 25 after artificial insemination. From day 18 after breeding onward, the mean ovPAG concentration was significantly higher (p < 0.001) in plasma samples from pregnant ewes (n ¼ 17) than in nonpregnant ones (n ¼ 3). The specific activity of the tracer was 11 760 Ci/mmol in RIA-780 and 14 900 Ci/mmol in RIA-805. The minimal detection limits for RIA-780 and RIA-805 were 0.2 ng/ml and 0.3 ng/ml, respectively. The intra-assay CV of samples with low (1.0 ng/ml), medium (2.5 ng/ml) and high (4.0 ng/ml) PAG concentrations were 3%, 6% and 9% for RIA-780 and 8%, 9% and 5% for RIA-805. The inter-assay CV in the same samples were 13%, 12% and 7% for RIA-780 and 13%, 11% and 5% for RIA-805. The recovery was higher than 95% in both assays. No cross-reaction was observed with members of aspartic proteinase family as well as with other tested proteins. In both RIA-780 and RIA-805, inhibition of the binding of the tracer by antisera was parallel between standard curve and serial dilutions of pregnant ewe samples. In conclusion, the two homologous RIA systems are suitable for early quantification of ovPAG concentrations in ewe plasma samples from day 18 after breeding.
Acta veterinaria Hungarica, Sep 1, 2017
Early embryonic development may be negatively affected by insufficient progesterone (P4) producti... more Early embryonic development may be negatively affected by insufficient progesterone (P4) production. Therefore, the aim of our study was to increase P4 by gonadotropin-releasing hormone (GnRH) and/or human chorionic gonadotropin (hCG) treatments after inducing oestrus by prostaglandin (PG) treatment. Lactating Simmental dairy cows (n = 110), between 1 to 5 lactations, with an average milk production of 6,500 1/305 days, at 40-80 days postpartum were used and grouped as follows: (1) PG + GnRH treatment at AI (GnRH group), (2) PG + hCG treatment at day 7 after AI (hCG group), (3) PG + GnRH at AI + hCG treatment at day 7 after AI (GnRH/hCG group), and (4) spontaneous oestrus (C: control group). All animals were double inseminated (at the time of oestrus detection and 12 ± 2 h thereafter). Blood serum and milk samples were collected at the day of observed oestrus (day 0), and 14, 21 and 28 days after AI. Serum P4 was determined using a commercial radioimmunoassay (RIA) test (INEP, Zemun...
Polish Journal of Veterinary Sciences
Animals
In cattle, initial pregnancy diagnosis takes place during the late embryonic/early fetal stage of... more In cattle, initial pregnancy diagnosis takes place during the late embryonic/early fetal stage of gestation. From this point onward, pregnancy loss may occur in up to one fifth of pregnancies before the initial pregnancy diagnosis is confirmed. This means the early identification of risk factors is a key part of pregnancy diagnosis and herd management. The various factors responsible for pregnancy losses are classified into infectious and noninfectious. Among the noninfectious causes, several dam-related (circumstances of the individual pregnancy or milk production) and herd-related factors causing stress have been well established. In this review, we summarize the impacts of these noninfectious factors and predict associated risks of pregnancy loss.
... un ulteriore leggero incremento, seppur temporaneo, nei loro livelli delle proteine, prima ch... more ... un ulteriore leggero incremento, seppur temporaneo, nei loro livelli delle proteine, prima che gli stessi diminuissero definitivamente, facendo ipotizzare che la produzione delle proteine da parte delle cellule ... URL: http://www.ismea.it/flex/FixedPages/IT/RicercaStampa.php/L/IT. ...
Reproduction in Domestic Animals, Jun 21, 2023
This study aimed to investigate the effectiveness of Duragen® and skimmed milk (SM) extenders on ... more This study aimed to investigate the effectiveness of Duragen® and skimmed milk (SM) extenders on the quality parameters, bacterial load and fertilization ability of stored ram semen. A total of 50 ejaculates from Sardi rams (n = 5) aged 2.5–3 years, were collected and stored in Duragen® and SM at 15°C. The motilities and velocity parameters generated by the CASA system were then evaluated at 0, 8 and 24 h of storage. Afterward, bacterial loads of sperm extended in Duragen® and SM were determined at 0, 5 and 24 h of incubation. In addition, ewes (n = 100) aged 2 years, have been chosen in the same herd. The selected ewes were then synchronized and inseminated using semen extended in Duragen® and SM and stored for 5 h at 15°C. The results revealed that total and progressive motilities, straight velocity (VSL), straightness (SRT), lateral head displacement (ALH) and beat cross frequency (BCF) were not affected by the extender type after 24 h of storage (p > .05). However, curvilinear velocity (VCL), velocity average path (VAP), linearity (LIN) and wobble (WOB) showed higher values in Duragen® compared with SM extender after 24 h of storage (p < .05). Bacterial loads were observed mainly in sperm stored in SM at 5 h (183 UFC/mL) and at 24 h (357 UFC/mL) of incubation. However, the only case showing a bacterial load in Duragen® is when the storage time attains 24 h (199 UFC/mL). Concerning fertility, sperm diluted in both extenders resulting in high fertility rates which reaches 66% and 73% for Duragen® and SM, respectively, with no statistical difference (p > .05). In summary, Duragen® extender decreased bacterial load in stored semen and maintained high ram sperm quality and fertility. These findings suggest that Duragen® extender could be used as SM alternative in ovine artificial insemination (OAI).
Animals
Prior to initiating any obstetrical intervention for anterior or posterior presentation, it is im... more Prior to initiating any obstetrical intervention for anterior or posterior presentation, it is imperative to emphasize the need for a precise and accurate diagnosis of fetal viability and to select the most appropriate approach for assistance. In uncertain cases, diagnostic tools such as ultrasonography, pulse oximeter, or measurement of acid–base balance or lactate concentration may be employed to confirm the diagnosis. In situations of severe asphyxia, a cesarean section is preferred over traction, even if the duration of asphyxia is less than 60 s, to maximize the likelihood of the survival of the fetus. Postcalving, several vitality scores have been proposed to evaluate the vigor of the newborn calf. Originally, four different clinical signs were recommended for assessing the well-being of newborn calves. Subsequently, five or more different clinical signs were recommended to evaluate vitality. However, despite the efforts for devising a practical tool to assess newborn calf vit...
Animals
The objective of the present study was to evaluate the changes in maternal and fetal arterial aci... more The objective of the present study was to evaluate the changes in maternal and fetal arterial acid-base variables withdrawn from catheterized dams and fetuses during the last days before and during calving. The average gestation length in nine cows with chronically catheterized fetuses was 285 ± 10 (SD) days. The arterial acid-base variables of a catheterized dam and fetus were very stable during late gestation. Four newborn calves showed small differences between prenatal and postnatal pH values (−0.035). At the same time, pCO2 values started to increase significantly (p = 0.02), indicating a shift towards physiological respiratory acidosis during calving. The partial pressure of oxygen and oxygen saturation values showed some non-significant improvements immediately after birth, while the other acid-base parameters did not differ. The remaining five newborn calves showed a significant decrease in arterial blood pH (p < 0.01) and BE (p = 0.01), while pCO2 tended to be higher (p ...
American Association of Bovine Practitioners Conference Proceedings
During the past 25 years, several methods were developed to synchronize estrus in dairy cattle. S... more During the past 25 years, several methods were developed to synchronize estrus in dairy cattle. Synchronization with prostaglandin F2α (PGF2α) is successful when cows are bred at a detected estrus because estrus detection rates and artificial insemination (Al) are more efficient than daily detection of estrus (Stevenson and Pursley, 1994). The success of estrous induction with PGF2α depends on the presence of a functional corpus luteum (CL). In case of a palpable CL, Archbald et al (1994) found that the percentage of milking cows observed in estrus within seven days after treatment (25 mg of PGF2α) was 55% (61/111). This management tool still does not control the time of AI, because estrus detection continues to be necessary, which is evidenced by the lower pregnancy rate after timed AI compared with AI after detected estrus. This might be partially explained by the variation in time of ovulation over periods of five days with respect to time of AI (Stevenson et al, 1987). Various a...
Journal of Veterinary Medicine Series A
SummaryBlood gas and acid‐base status of 44 Caesarean‐derived calves (all in anterior presentatio... more SummaryBlood gas and acid‐base status of 44 Caesarean‐derived calves (all in anterior presentation) were determined in blood samples obtained before the onset of extraction and after it. Calves were assigned to one of three groups according to their blood pH value: group 1 = normal, pH above 7.2; group 2 = slightly acidotic, pH 7.2 to 7.0; group 3 = severely acidotic, pH below 7.0. Before the onset of extraction (i.e. 4 to 5 hours after the appearance and spontaneous rupture of foetal membranes), 28 calves (63.6%) had normal acid‐base values, 10 (22.7%) had slight acidosis, and 6 (13.7%) had severe acidosis. Vigorous leg movements during extraction direct attention to the occurrence of severe acidosis. At birth the three groups of calves showed the following distribution: 22 (50%) were normal, 15 (34.1 %) had slight acidosis, and 7 (15.9%) had severe acidosis. The acid‐base balance of calves during extraction was mainly shifted to respiratory acidosis. During the first ten minutes a...
Animal Husbandry
Parallel with the successful genetic selection for higher milk production in Holstein-Friesian co... more Parallel with the successful genetic selection for higher milk production in Holstein-Friesian cows, a dramatic decline in fertility rates has been observed around the world. Therefore, to achieve an optimum herd reproductive performance, we must focus on the first 100 days postpartum. During and after calving, a cow overcomes a series of physiological hurdles before becoming pregnant. By selecting accurate diagnostic devices and/or methods, such as predicting the onset of calving, monitoring activity and rumination time to determine cows for early treatment of clinical metritis and/or metabolic diseases, long-term measurement of reticuloruminal pH to monitor subclinical acidosis, perform metabolic profile tests to diagnose subclinical metabolic diseases at the herd level, estrous detectors and/or detection aids, on-farm/in-line P4 test to monitor specific events in the postpartum periods, diagnosis of early pregnancy and pregnancy loss using ultrasonography to correctly identify pr...
Due to the successful genetic selection for higher milk production in Holstein dairy cows, a dram... more Due to the successful genetic selection for higher milk production in Holstein dairy cows, a dramatic decline in fertility rates has been observed around in the world in recent decades. Therefore, herd management should focus the first 100 days postpartum to achieve optimum herd reproductive performance (calving interval less than 400 days). After calving, a cow has to overcome a series of physiological hurdles before becoming pregnant. The selection of timely diagnostic devices and methods, such as the calving alarm vaginal thermometer to predict the onset of calving, electronic hand-held BHBA measuring system to detect subclinical ketosis on the farm, long-term measurement of reticuloruminal pH by an indwelling and wireless data transmitting unit to monitor subclinical acidosis, monitoring rumination time to select cows for early treatment of subclinical metabolic diseases (subclinical ketosis, acidosis and/or hypocalcaemia) and/or clinical metritis, performing metabolic profile t...
Animals
Besides traditional methods such as evaluation of the external preparatory and behavioral signs, ... more Besides traditional methods such as evaluation of the external preparatory and behavioral signs, which even presently are widely used also in large dairy farms, there are several new possibilities such as measuring body (intravaginal, ventral tail-base surface, ear surface, or reticulo-ruminal) temperature, detecting behavioral signs (rumination, eating, activity, tail raising) or detecting the expulsion of the device inserted into the vagina or fixed to the skin of the vulva when allantochorion appears in the vulva to predict the onset of the second stage of calving. Presently none of the single sensors or a combination of sensors can predict the onset of calving with acceptable accuracy. At the same time, with the exception of the iVET® birth monitoring system, not only the imminent onset of calving could be predicted with high accuracy, but a significantly lower prevalence rate of dystocia, stillbirth, retained fetal membranes, uterine diseases/clinical metritis could be reached ...
CABI Reviews
At present, the main emphasis is on preventing asphyxia, since instruments suitable for artificia... more At present, the main emphasis is on preventing asphyxia, since instruments suitable for artificial respiration in calves under practical conditions are not yet widely available. The most important breeding objective is to reduce the number of births in which calving assistance is required. This is even more important, since calving assistance in itself may result in a shift of the calf's acid-base balance. In cases of difficult calving, the mode and time of calving assistance should be chosen with regard to profitability factors and in a manner to allow the least possible shift of the calf's acid-base balance towards acidosis. Before applying traction, the measurements of the soft birth canal should always be considered and if necessary must be expanded non-surgically or surgically, and obstetrical lubricants should be used to avoid traction for longer than 2 to 3 minutes. If a prolonged traction is expected, a caesarean section should be carried out to save the calf and to ...
Animals
Here we revise circumstances of non-infectious causes in which the uterus may be associated with ... more Here we revise circumstances of non-infectious causes in which the uterus may be associated with pregnancy loss during the late embryo/early fetal period (following a positive pregnancy diagnosis in lactating dairy cows). As the uterine size increases with parity and pregnant heifers with no detrimental effects of a previous parturition, a primigravid uterus is proposed as a reference for identifying risk factors that negatively influence pregnancy in lactating cows. Cows suffering placenta retention or with a large uterus at insemination were selected as topics for this revision. Retained placenta, that occurs around parturition, has a long-lasting influence on subsequent pregnancy loss. Although retained placenta is a particularly predisposing factor for uterine infection, farm conditions along with cow factors of non-infectious cause and their interactions have been identified as main factors favoring this disorder. A large uterus (cervix and uterine horns lying outside the pelvi...
Magyar Allatorvosok Lapja, 2018
Animals, 2021
One of the most recent techniques for the on-farm diagnosis of early pregnancy (EP) in cattle is ... more One of the most recent techniques for the on-farm diagnosis of early pregnancy (EP) in cattle is B-mode ultrasonography. Under field conditions, acceptable results may be achieved with ultrasonography from Days 25 to 30 post-AI. The reliability of the test greatly depends on the frequency of the transducer used, the skill of the examiner, the criterion used for a positive pregnancy diagnosis (PD), and the position of the uterus in the pelvic inlet. Non-pregnant animals can be selected accurately by evaluating blood flow in the corpus luteum around Day 20 after AI, meaning we can substantially improve the reproductive efficiency of our herd. Pregnancy protein assays (PSPB, PAG-1, and PSP60 RIA, commercial ELISA or rapid visual ELISA tests) may provide an alternative method to ultrasonography for determining early pregnancy or late embryonic/early fetal mortality (LEM/EFM) in dairy cows. Although the early pregnancy factor is the earliest specific indicator of fertilization, at presen...
The aim of the present study was: i) to investigate the use of PAGs for pregnancy follow up in Bo... more The aim of the present study was: i) to investigate the use of PAGs for pregnancy follow up in Boujaâd non prolific (n=8) vs. Boujaâd x D’man a prolific sheep (n=20), ii) to study whether the boPAG tracer (daily available at the laboratory of physiology of reproduction, Liège, could be used in RIA without affecting the results, iii) to prospect the possibility of transferring the technique to a Moroccan laboratory. The blood samples were weekly collected from the first week of gestation till the 4 week after lambing. The RIA1, RIA2, RIA3 and RIA4 were all based on ovPAG standard, while the tracer and antiserum changed according to the system. The RIA1, RIA3 and RIA4 were performed in Belgium while the RIA2 was carried out in Morocco. The results showed that the highest correlation was obtained between the RIA3 and RIA4 (R2 = 0.83) while the lowest was recorded between the RIA2 and RIA4 (R2 = 0.69). The lowest concentrations derived from the RIA2. The highest concentrations were recorded before lambing (279.29; 88.21; 268.75; 152.67 ng/ml respectively for RIAs 1, 2, 3 and 4). To conclude, the profiles of ovPAG showed that it is possible to flow-up with success using the four systems. In addition, the RIA1 using boPAG as tracer could be a good alternative to the homologous one and finally, it is possible to set up routinely the RIA technique for PAG detection in Moroccan laboratories
Magyar Allatorvosok Lapja, 1999
Reproduction in Domestic Animals, 2007
This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune... more This study describes ovine pregnancy-associated glycoprotein (ovPAG) concentrations in 20 Lacaune sheep during early pregnancy. Measurements were performed by using semipurified ovPAG as standard, tracer and immunogens for antibody production in rabbits. Antisera R780 (against ovPAG 57+59kDa) and R805 (against ovPAG5 58+61kDa) were used respectively in RIA-780 and RIA-805. Blood samples were collected at days 0, 18, 20, 22 and 25 after artificial insemination. From day 18 after breeding onward, the mean ovPAG concentration was significantly higher (p < 0.001) in plasma samples from pregnant ewes (n ¼ 17) than in nonpregnant ones (n ¼ 3). The specific activity of the tracer was 11 760 Ci/mmol in RIA-780 and 14 900 Ci/mmol in RIA-805. The minimal detection limits for RIA-780 and RIA-805 were 0.2 ng/ml and 0.3 ng/ml, respectively. The intra-assay CV of samples with low (1.0 ng/ml), medium (2.5 ng/ml) and high (4.0 ng/ml) PAG concentrations were 3%, 6% and 9% for RIA-780 and 8%, 9% and 5% for RIA-805. The inter-assay CV in the same samples were 13%, 12% and 7% for RIA-780 and 13%, 11% and 5% for RIA-805. The recovery was higher than 95% in both assays. No cross-reaction was observed with members of aspartic proteinase family as well as with other tested proteins. In both RIA-780 and RIA-805, inhibition of the binding of the tracer by antisera was parallel between standard curve and serial dilutions of pregnant ewe samples. In conclusion, the two homologous RIA systems are suitable for early quantification of ovPAG concentrations in ewe plasma samples from day 18 after breeding.
Acta veterinaria Hungarica, Sep 1, 2017
Early embryonic development may be negatively affected by insufficient progesterone (P4) producti... more Early embryonic development may be negatively affected by insufficient progesterone (P4) production. Therefore, the aim of our study was to increase P4 by gonadotropin-releasing hormone (GnRH) and/or human chorionic gonadotropin (hCG) treatments after inducing oestrus by prostaglandin (PG) treatment. Lactating Simmental dairy cows (n = 110), between 1 to 5 lactations, with an average milk production of 6,500 1/305 days, at 40-80 days postpartum were used and grouped as follows: (1) PG + GnRH treatment at AI (GnRH group), (2) PG + hCG treatment at day 7 after AI (hCG group), (3) PG + GnRH at AI + hCG treatment at day 7 after AI (GnRH/hCG group), and (4) spontaneous oestrus (C: control group). All animals were double inseminated (at the time of oestrus detection and 12 ± 2 h thereafter). Blood serum and milk samples were collected at the day of observed oestrus (day 0), and 14, 21 and 28 days after AI. Serum P4 was determined using a commercial radioimmunoassay (RIA) test (INEP, Zemun...
Polish Journal of Veterinary Sciences
Animals
In cattle, initial pregnancy diagnosis takes place during the late embryonic/early fetal stage of... more In cattle, initial pregnancy diagnosis takes place during the late embryonic/early fetal stage of gestation. From this point onward, pregnancy loss may occur in up to one fifth of pregnancies before the initial pregnancy diagnosis is confirmed. This means the early identification of risk factors is a key part of pregnancy diagnosis and herd management. The various factors responsible for pregnancy losses are classified into infectious and noninfectious. Among the noninfectious causes, several dam-related (circumstances of the individual pregnancy or milk production) and herd-related factors causing stress have been well established. In this review, we summarize the impacts of these noninfectious factors and predict associated risks of pregnancy loss.
... un ulteriore leggero incremento, seppur temporaneo, nei loro livelli delle proteine, prima ch... more ... un ulteriore leggero incremento, seppur temporaneo, nei loro livelli delle proteine, prima che gli stessi diminuissero definitivamente, facendo ipotizzare che la produzione delle proteine da parte delle cellule ... URL: http://www.ismea.it/flex/FixedPages/IT/RicercaStampa.php/L/IT. ...
Reproduction in Domestic Animals, Jun 21, 2023
This study aimed to investigate the effectiveness of Duragen® and skimmed milk (SM) extenders on ... more This study aimed to investigate the effectiveness of Duragen® and skimmed milk (SM) extenders on the quality parameters, bacterial load and fertilization ability of stored ram semen. A total of 50 ejaculates from Sardi rams (n = 5) aged 2.5–3 years, were collected and stored in Duragen® and SM at 15°C. The motilities and velocity parameters generated by the CASA system were then evaluated at 0, 8 and 24 h of storage. Afterward, bacterial loads of sperm extended in Duragen® and SM were determined at 0, 5 and 24 h of incubation. In addition, ewes (n = 100) aged 2 years, have been chosen in the same herd. The selected ewes were then synchronized and inseminated using semen extended in Duragen® and SM and stored for 5 h at 15°C. The results revealed that total and progressive motilities, straight velocity (VSL), straightness (SRT), lateral head displacement (ALH) and beat cross frequency (BCF) were not affected by the extender type after 24 h of storage (p > .05). However, curvilinear velocity (VCL), velocity average path (VAP), linearity (LIN) and wobble (WOB) showed higher values in Duragen® compared with SM extender after 24 h of storage (p < .05). Bacterial loads were observed mainly in sperm stored in SM at 5 h (183 UFC/mL) and at 24 h (357 UFC/mL) of incubation. However, the only case showing a bacterial load in Duragen® is when the storage time attains 24 h (199 UFC/mL). Concerning fertility, sperm diluted in both extenders resulting in high fertility rates which reaches 66% and 73% for Duragen® and SM, respectively, with no statistical difference (p > .05). In summary, Duragen® extender decreased bacterial load in stored semen and maintained high ram sperm quality and fertility. These findings suggest that Duragen® extender could be used as SM alternative in ovine artificial insemination (OAI).
Animals
Prior to initiating any obstetrical intervention for anterior or posterior presentation, it is im... more Prior to initiating any obstetrical intervention for anterior or posterior presentation, it is imperative to emphasize the need for a precise and accurate diagnosis of fetal viability and to select the most appropriate approach for assistance. In uncertain cases, diagnostic tools such as ultrasonography, pulse oximeter, or measurement of acid–base balance or lactate concentration may be employed to confirm the diagnosis. In situations of severe asphyxia, a cesarean section is preferred over traction, even if the duration of asphyxia is less than 60 s, to maximize the likelihood of the survival of the fetus. Postcalving, several vitality scores have been proposed to evaluate the vigor of the newborn calf. Originally, four different clinical signs were recommended for assessing the well-being of newborn calves. Subsequently, five or more different clinical signs were recommended to evaluate vitality. However, despite the efforts for devising a practical tool to assess newborn calf vit...
Animals
The objective of the present study was to evaluate the changes in maternal and fetal arterial aci... more The objective of the present study was to evaluate the changes in maternal and fetal arterial acid-base variables withdrawn from catheterized dams and fetuses during the last days before and during calving. The average gestation length in nine cows with chronically catheterized fetuses was 285 ± 10 (SD) days. The arterial acid-base variables of a catheterized dam and fetus were very stable during late gestation. Four newborn calves showed small differences between prenatal and postnatal pH values (−0.035). At the same time, pCO2 values started to increase significantly (p = 0.02), indicating a shift towards physiological respiratory acidosis during calving. The partial pressure of oxygen and oxygen saturation values showed some non-significant improvements immediately after birth, while the other acid-base parameters did not differ. The remaining five newborn calves showed a significant decrease in arterial blood pH (p < 0.01) and BE (p = 0.01), while pCO2 tended to be higher (p ...
American Association of Bovine Practitioners Conference Proceedings
During the past 25 years, several methods were developed to synchronize estrus in dairy cattle. S... more During the past 25 years, several methods were developed to synchronize estrus in dairy cattle. Synchronization with prostaglandin F2α (PGF2α) is successful when cows are bred at a detected estrus because estrus detection rates and artificial insemination (Al) are more efficient than daily detection of estrus (Stevenson and Pursley, 1994). The success of estrous induction with PGF2α depends on the presence of a functional corpus luteum (CL). In case of a palpable CL, Archbald et al (1994) found that the percentage of milking cows observed in estrus within seven days after treatment (25 mg of PGF2α) was 55% (61/111). This management tool still does not control the time of AI, because estrus detection continues to be necessary, which is evidenced by the lower pregnancy rate after timed AI compared with AI after detected estrus. This might be partially explained by the variation in time of ovulation over periods of five days with respect to time of AI (Stevenson et al, 1987). Various a...
Journal of Veterinary Medicine Series A
SummaryBlood gas and acid‐base status of 44 Caesarean‐derived calves (all in anterior presentatio... more SummaryBlood gas and acid‐base status of 44 Caesarean‐derived calves (all in anterior presentation) were determined in blood samples obtained before the onset of extraction and after it. Calves were assigned to one of three groups according to their blood pH value: group 1 = normal, pH above 7.2; group 2 = slightly acidotic, pH 7.2 to 7.0; group 3 = severely acidotic, pH below 7.0. Before the onset of extraction (i.e. 4 to 5 hours after the appearance and spontaneous rupture of foetal membranes), 28 calves (63.6%) had normal acid‐base values, 10 (22.7%) had slight acidosis, and 6 (13.7%) had severe acidosis. Vigorous leg movements during extraction direct attention to the occurrence of severe acidosis. At birth the three groups of calves showed the following distribution: 22 (50%) were normal, 15 (34.1 %) had slight acidosis, and 7 (15.9%) had severe acidosis. The acid‐base balance of calves during extraction was mainly shifted to respiratory acidosis. During the first ten minutes a...
Animal Husbandry
Parallel with the successful genetic selection for higher milk production in Holstein-Friesian co... more Parallel with the successful genetic selection for higher milk production in Holstein-Friesian cows, a dramatic decline in fertility rates has been observed around the world. Therefore, to achieve an optimum herd reproductive performance, we must focus on the first 100 days postpartum. During and after calving, a cow overcomes a series of physiological hurdles before becoming pregnant. By selecting accurate diagnostic devices and/or methods, such as predicting the onset of calving, monitoring activity and rumination time to determine cows for early treatment of clinical metritis and/or metabolic diseases, long-term measurement of reticuloruminal pH to monitor subclinical acidosis, perform metabolic profile tests to diagnose subclinical metabolic diseases at the herd level, estrous detectors and/or detection aids, on-farm/in-line P4 test to monitor specific events in the postpartum periods, diagnosis of early pregnancy and pregnancy loss using ultrasonography to correctly identify pr...
Due to the successful genetic selection for higher milk production in Holstein dairy cows, a dram... more Due to the successful genetic selection for higher milk production in Holstein dairy cows, a dramatic decline in fertility rates has been observed around in the world in recent decades. Therefore, herd management should focus the first 100 days postpartum to achieve optimum herd reproductive performance (calving interval less than 400 days). After calving, a cow has to overcome a series of physiological hurdles before becoming pregnant. The selection of timely diagnostic devices and methods, such as the calving alarm vaginal thermometer to predict the onset of calving, electronic hand-held BHBA measuring system to detect subclinical ketosis on the farm, long-term measurement of reticuloruminal pH by an indwelling and wireless data transmitting unit to monitor subclinical acidosis, monitoring rumination time to select cows for early treatment of subclinical metabolic diseases (subclinical ketosis, acidosis and/or hypocalcaemia) and/or clinical metritis, performing metabolic profile t...
Animals
Besides traditional methods such as evaluation of the external preparatory and behavioral signs, ... more Besides traditional methods such as evaluation of the external preparatory and behavioral signs, which even presently are widely used also in large dairy farms, there are several new possibilities such as measuring body (intravaginal, ventral tail-base surface, ear surface, or reticulo-ruminal) temperature, detecting behavioral signs (rumination, eating, activity, tail raising) or detecting the expulsion of the device inserted into the vagina or fixed to the skin of the vulva when allantochorion appears in the vulva to predict the onset of the second stage of calving. Presently none of the single sensors or a combination of sensors can predict the onset of calving with acceptable accuracy. At the same time, with the exception of the iVET® birth monitoring system, not only the imminent onset of calving could be predicted with high accuracy, but a significantly lower prevalence rate of dystocia, stillbirth, retained fetal membranes, uterine diseases/clinical metritis could be reached ...
CABI Reviews
At present, the main emphasis is on preventing asphyxia, since instruments suitable for artificia... more At present, the main emphasis is on preventing asphyxia, since instruments suitable for artificial respiration in calves under practical conditions are not yet widely available. The most important breeding objective is to reduce the number of births in which calving assistance is required. This is even more important, since calving assistance in itself may result in a shift of the calf's acid-base balance. In cases of difficult calving, the mode and time of calving assistance should be chosen with regard to profitability factors and in a manner to allow the least possible shift of the calf's acid-base balance towards acidosis. Before applying traction, the measurements of the soft birth canal should always be considered and if necessary must be expanded non-surgically or surgically, and obstetrical lubricants should be used to avoid traction for longer than 2 to 3 minutes. If a prolonged traction is expected, a caesarean section should be carried out to save the calf and to ...
Animals
Here we revise circumstances of non-infectious causes in which the uterus may be associated with ... more Here we revise circumstances of non-infectious causes in which the uterus may be associated with pregnancy loss during the late embryo/early fetal period (following a positive pregnancy diagnosis in lactating dairy cows). As the uterine size increases with parity and pregnant heifers with no detrimental effects of a previous parturition, a primigravid uterus is proposed as a reference for identifying risk factors that negatively influence pregnancy in lactating cows. Cows suffering placenta retention or with a large uterus at insemination were selected as topics for this revision. Retained placenta, that occurs around parturition, has a long-lasting influence on subsequent pregnancy loss. Although retained placenta is a particularly predisposing factor for uterine infection, farm conditions along with cow factors of non-infectious cause and their interactions have been identified as main factors favoring this disorder. A large uterus (cervix and uterine horns lying outside the pelvi...
Magyar Allatorvosok Lapja, 2018
Animals, 2021
One of the most recent techniques for the on-farm diagnosis of early pregnancy (EP) in cattle is ... more One of the most recent techniques for the on-farm diagnosis of early pregnancy (EP) in cattle is B-mode ultrasonography. Under field conditions, acceptable results may be achieved with ultrasonography from Days 25 to 30 post-AI. The reliability of the test greatly depends on the frequency of the transducer used, the skill of the examiner, the criterion used for a positive pregnancy diagnosis (PD), and the position of the uterus in the pelvic inlet. Non-pregnant animals can be selected accurately by evaluating blood flow in the corpus luteum around Day 20 after AI, meaning we can substantially improve the reproductive efficiency of our herd. Pregnancy protein assays (PSPB, PAG-1, and PSP60 RIA, commercial ELISA or rapid visual ELISA tests) may provide an alternative method to ultrasonography for determining early pregnancy or late embryonic/early fetal mortality (LEM/EFM) in dairy cows. Although the early pregnancy factor is the earliest specific indicator of fertilization, at presen...
The aim of the present study was: i) to investigate the use of PAGs for pregnancy follow up in Bo... more The aim of the present study was: i) to investigate the use of PAGs for pregnancy follow up in Boujaâd non prolific (n=8) vs. Boujaâd x D’man a prolific sheep (n=20), ii) to study whether the boPAG tracer (daily available at the laboratory of physiology of reproduction, Liège, could be used in RIA without affecting the results, iii) to prospect the possibility of transferring the technique to a Moroccan laboratory. The blood samples were weekly collected from the first week of gestation till the 4 week after lambing. The RIA1, RIA2, RIA3 and RIA4 were all based on ovPAG standard, while the tracer and antiserum changed according to the system. The RIA1, RIA3 and RIA4 were performed in Belgium while the RIA2 was carried out in Morocco. The results showed that the highest correlation was obtained between the RIA3 and RIA4 (R2 = 0.83) while the lowest was recorded between the RIA2 and RIA4 (R2 = 0.69). The lowest concentrations derived from the RIA2. The highest concentrations were recorded before lambing (279.29; 88.21; 268.75; 152.67 ng/ml respectively for RIAs 1, 2, 3 and 4). To conclude, the profiles of ovPAG showed that it is possible to flow-up with success using the four systems. In addition, the RIA1 using boPAG as tracer could be a good alternative to the homologous one and finally, it is possible to set up routinely the RIA technique for PAG detection in Moroccan laboratories
Magyar Allatorvosok Lapja, 1999