Ultrasonographic fetometry and determination of fetal sex in buffaloes (Bubalus bubalis)

Development and growth of bovine calves demi-embryos

The aim of this study was to investigate the growth and development of animals produced from demi-embryos and compare them with whole embryos from fetus to adult life. To achieve this, calves produced from fresh demi-embryos and whole embryos were individually transferred and monitored from 60 days of pregnancy until slaughter at 550 days. Ultrasound scans were conducted on fetuses at 60 and 90 days to evaluate the biparietal, abdominal, umbilical cord, orbital, and aorta diameters. Subsequently, morphological traits of newborn calves were measured at 0, 7, and 21 days (N = 18). Live weight was recorded at birth, weaning, and every 30 days thereafter until slaughter at 550 days. The growth curve of each group was modeled using logistic regression, and the factors of the respective functions were compared. As early as 60 days of pregnancy, ultrasound evaluations revealed no morphometric differences between fetuses produced from demi-embryos and those from whole embryos. This lack of differentiation persisted in the morphometric evaluations of newborns up to 21 days of age, as well as in live weight and the growth curve from birth to slaughter. Moreover, there were no significant differences between the groups in terms of rib eye area and fat thickness evolution. Consequently, individuals from demi-embryos exhibited no discernible disparities to those whole embryos in growth and development from 60 days of gestation, through birth, and into adulthood.

Estimation of gestational age in buffaloes (Bubalus bubalis) by transabdominal and transrectal ultrasonography

The aims of the presented study were (1) to examine the relationship between foetal measurements and gestational age (GA), (2) to generate GA formulas, and (3) to investigate the estimation of GA by transabdominal ultrasonography in buffaloes. Thirteen pregnant buffaloes were used in the study. Transrectal ultrasonography was performed between Day (D) 28 and 112 of gestational age, whereas transabdominal ultrasonography was between 126 and 294. The diameters of embryonic (EVD) and amniotic (AVD) vesicles, crown-rump length (CRL), occipito-nasal length (ONL), biparietal diameter (BPD), orbit diameter (OD), cervical, thoracic, lumbar and coccygeal vertebrae lengths (CVL, TVL, LVL, CcVL), abdominal diameter (AD), chest diameter (CD), umbilical cord diameter (UCD), scapula, humerus, radius-ulna, metacarpus, femur, tibia, and metatarsus lengths (SL, HL, RUL, McL, FL, TL, MtL), diameters of transversal heart (THD), stomach (SD), kidney (KD), and outer diameter, circumference and area of placentomas (OPD, OPC, OPA) were measured by ultrasonography. All 26 parameters were highly correlated with GA (r = 0.968 - 0.999). The observation of the foetus was evident in all animals via transabdominal ultrasonography, and all parameters except EVD, AVD, and CRL could be measured on D 126. In addition, heartbeats, the sign of foetal vitality, could be observed in 11 of 13 living foetuses. This study is the first to demonstrate that transabdominal ultrasonography can be used to estimate GA in buffaloes. In addition, GA formulas related to ONL, CVL, TVL, LVL, CcVL, extremity bone lengths, THD, UCD, PC, and PA measurements were created for the first time in buffaloes.

Study on Various Luteal Characteristics Using Doppler Ultrasonography for Early Pregnancy Diagnosis in Nili-Ravi Buffaloes

The objective of current study was to assess the trend in various luteal characteristics viz luteal size (LS), plasma progesterone (P⁴) concentration, and luteal blood flow (LBF) using color Doppler imaging (CDI) and power Doppler imaging (PDI) modes in pregnant and nonpregnant Nili-Ravi buffaloes. Lactating, cyclic, and healthy Nili-Ravi buffaloes (n = 09) without any reproductive abnormality were selected in present study. Buffaloes were synchronized using Ov-Synch, and fixed-time artificially insemination was performed (day = 0). Pregnancy was diagnosed on 30-day post-AI using B-mode ultrasonography based on presence or absence of embryonic heartbeat. Ovaries of all animals were scanned from day 5 till 21 post-AI using both B-mode and Doppler ultrasonography to measure LS and LBF. After each ovarian ultrasound examination, blood samples were collected via jugular venipuncture to determine plasma P⁴ concentration. According to results, LBF using CDI and PDI was significantly higher (P ≤ 0.05) in pregnant buffaloes on days 13 and 15 post-AI, respectively. The mean LS and plasma P⁴ concentration did not differ (P ≥ 0.05) between pregnant and nonpregnant animals until day 15 post-AI. However, a significant difference (P ≤ 0.05) was noticed for both on day 17 and onwards. It is concluded that LBF is a more sensitive luteal character as compared to LS and P⁴ for earlier pregnancy diagnosis in Nili-Ravi buffaloes when ascertained through CDI.

Use and adequacy of non-pregnancy diagnosis in cow. Which future?

In cattle, early detection of gestation is very important from an economic and management point of view in all types of farming. However, due to the poor efficiency of oestrus detection, it is essential to determine non-pregnant cows as early possible, in order to minimize the inter-insemination interval, thus de facto, reducing herd open days. Direct and indirect gestation diagnostic methods have been developed with the aim of improving the reproductive performance of the herd. Today, the most accurate method for making an early diagnosis of gestation from 28-30 days post insemination is B-Mode ultrasound. In recent years, indirect methods have included techniques that allow non-pregnant cows to be identified with a minimum margin of error, the most widely utilized of which is the Color-Doppler. This technique is rapidly becoming established for the diagnosis of non-pregnancy that allows the identification of non-pregnant animals earlier compared the pregnancy diagnosis. Some limitations of this technique in dairy cow have been presented.

Approaches to Identify Pregnancy Failure in Buffalo Cows

Simple Summary

Embryonic mortality and pregnancy failures still represent a major issue in domestic livestock production, particularly in dairy cattle. Despite the presence of extensive work in this research area, there is still no effective, accurate and practical method able to determine timing and viability of embryo specifically during early gestation. Indeed, technologies and techniques for predicting pregnancy success must continue to be developed. The aim of this work was to find the best strategy to diagnose pregnancy failures in buffalo cows in order to improve farm reproductive management. Among the methods compared in this study (ultrasonography, progesterone, PAGs), pregnancy-associated glycoproteins (PAGs) seem to be the best marker for predicting embryonic mortality between 25 and 40 days of gestation to be utilized as a diagnostic tool to improve reproductive management in buffalo farms.

Abstract

The aim of this work was to find the best strategy to diagnose pregnancy failures in buffalo. A total of 109 animals belonging to a buffalo herd subjected to a synchronization and artificial insemination (AI) program were enrolled in this study. Blood samples were collected at days 0, 14, 25, 28 and 40 after AI for the determination of progesterone (P4) and pregnancy-associated glycoproteins (PAGs) by the radioimmunoassay (RIA) method. Transrectal ultrasonography was performed on day 25, 28 and 40 after AI to monitor pregnancy. The animals included in the data analysis were assigned ex post in pregnant (n = 50) and mortality (n = 12) groups. By ultrasonography, the predictive sign of mortality was the heartbeat. At day 25, the PAGs concentration was significant in predicting embryonic mortality with respect to ultrasonography and P4, at the cut-off of 1.1 ng/mL. At day 28, either PAGs, at a cut-off of 2.2 ng/mL, or ultrasonography, with no detection of heartbeat, were highly predictive of embryonic mortality. PAGs were the best marker (p < 0.05) for predicting embryonic mortality between 25 and 40 days of gestation in buffalo. Its utilization as a diagnostic tool can influence management decisions in order to improve farm reproductive management.

Postpartum Uterine Involution and Embryonic Development Pattern in Chinese Holstein Dairy Cows

Understanding the postpartum uterine involution pattern and embryonic development could facilitate bovine reproduction management, improve reproductive efficiency, and diagnosis of the reproductive disorder, which would contribute to the success of the dairy business. This study aimed to investigate postpartum uterine involution and embryonic developmental patterns or postconceptional marks of embryonic fetal development in Chinese Holstein dairy cows using B-mode ultrasonography. The results revealed a significant decline in the involution period with an increase of parity and age. The uterine involution period was shorter in multiparous cows when compared with cows with lower parities. Consistently, cows over 4 years old recovered faster than younger cows (2 or 3 years). Besides, the elder cows (over 4 years) had a relatively larger size of resumed cervix uteri and horns. Postpartum uterine involution pattern analysis revealed that the reproductive tract recovered very fast during the first 16 days postpartum for all the parity. Results of postconceptional marks of embryo development revealed a slow increase in diameter of the gravid uterine horn and crown-rump length (CRL) before day 60. In contrast, this increase was dramatic and rapid after the 60th day. We also established two models to estimate gestational age based on gravid uterine horn diameter or CRL. A formula was established to determine the gravid uterine horn size during postconceptional on day 30th–day 90th (r = 0.8714, P < 0.01). In addition, a significant positive correlation between CRL and gestational age (r = 0.98151, P < 0.01) was built. In conclusion, these results illustrated that parity and calving age had significant effects on uterine involution in Chinese Holstein cows. Crown-rump length and gravid uterine horn diameter are both efficient for evaluating the embryo growth. These current findings broaden the understanding of basic reproductive pattern in Chinese Holstein cows and could benefit bovine reproductive management primarily in postpartum and early pregnant cows to reduce the calving interval and avoid periparturient metabolic diseases.

ALYE, M. ALHT. Clinical and Ultrasonic Study for Detection of Pregnancy in Iraqi Buffaloes

The present study was conducted on 10 Iraqi pregnant buffaloes aged between 3-6 years at Al-Qasim district- Babylon province, Iraq from December 2018 to December 2019. Those animals diagnosed by rectal palpation and ultrasonography technique to estimate the reproduction status. The results of this study reported wandering of ovum in 10% of animals (1/10). While ultrasonography characterized by increasing placentomes measurement gradually with development of gestation, and the placentomes recorded 8.32±2.46 mm, 13.27±3.25 mm, 18.37±5.34 mm, 23.25±8.63 mm and 28.2±6.87 mm in the 2nd , 3rd, 4th, 5th and 6th month, respectively. Also the total size was recorded by the crown rump length (CRL), which was 0.77±0.05 cm, 5.81±2.54 cm and 14.09±0.73 cm in the 1st, 2nd, and 3rd month, respectively. The heart beat and embryonic vesicle during the 1st and 2nd month were detectable by ultrasonography. In conclusions in the present study, rectal palpation and ultrasonography technique represented one of the most important methods to estimate the gestation period in different stages.

Two dimensional trans-rectal ultrasonographic studies in early pregnant murrah buffaloes

Two dimensional ultrasonographic studies were conducted in six pregnant Murrah buffaloes using 5.0-7.5 MHz frequency rectal probe twice a week from day 18 to 60 days followed by weekly interval up to 90 days postin semination. Two dimensional images of antenatal fetal organs particularly fetal stomach, eye, limbs, heart, umbilical cord, thorax, liver and placentomes were imaged and variat ions in size of placentome, stomach and crown rump length were measured. Fetal heart beat was measured from day 26 to 90 which decreased with advancement of gestation. From the present study it may be concluded that early pregnancy can be diagnosed ultrasonogra phicallythrough trans-rectal approach by day 26 post insemination.

Histological characteristics of the gonads of pig fetuses and their relationship with fetal anatomical measurements

The objective was to evaluate the histomorphometric characteristics of the testis and ovaries of pig fetuses at different gestational ages, as well as their correlation with some fetus measurements. Forty-four fetuses were separated for gender (male and female) and gestational age (50, 80 and 106days of gestation). After slaughter, fetuses had their body length, head and thoracic perimeters measured and their gonads submitted to histomorphometric analyses. The gonadal characteristics at different gestational ages were statistically compared, correlations with the fetal measurements were performed and equations to predict the gonadal characteristics from the fetal measurements were obtained. The testis weight logarithmically increased along pregnancy, whereas ovary weight increased in a linear manner. The cordonal length and number of Sertoli cells were positively correlated with the fetal measurements, being higher at 106days gestation, while the nuclear volume of these cells were negatively correlated. The total number of follicles was higher at day 80 and 106 of pregnancy. The number of oogonia decreased along the pregnancy, however, their nucleus size was increased. The number of follicles and volume of oogonia were positively correlated with the fetal measurements, while the number of oogonia was negatively correlated. Equations were obtained for the prediction of gonadal characteristics of fetuses. We concluded that in pigs testis cell proliferation, ovary development and histological organization was more pronounced during the final third of pregnancy. Fetal weight and size were strongly related to gonadal development, and can be used to estimate the histological characteristics of gonads.

Transuterine embryo migration, distribution of sexes within uterine horns, and fetometry in Nellore (Bos indicus) cattle

There is no consensus about the occurrence of transuterine embryo migration under natural breeding circumstances, neither data related to this phenomenon for zebu cattle. In this study, 5431 reproductive tracts of Nellore cows and heifers were evaluated in an abattoir in the state of Mato Grosso do Sul. A total of 1030 animals (19.0%) were pregnant at the time of slaughter (including 2 twin pregnancies). Regarding singleton pregnancies (n = 1028), 39.5% of them, the fetus was located in the left uterine horn and the remaining 60.5% in the right. These frequencies differed statistically from parity. In all 1028 (100.0%) cases, the presence of a single CL was perceived in the ovary ipsilateral (whether right or left) to the pregnant uterine horn, indicating the absence of transuterine embryo migration of the conceptus. The overall sex ratio found was 51.5%, considering only pregnancies with sex identified, not differing significantly between the number of males and the number of females. The sex frequencies obtained from the total number of singleton pregnancies were 46.5% males, 43.9% females, and the remaining 9.6% corresponding to unknown sex fetuses. The supposed sex predilection for uterine horns was not observed because the difference between the numbers of males and females for the same uterine horn was not statistically significant. The crown-rump (CR) and crown-nose (CN) measures, for the conceptus with CR length 2.00 cm to 15.00 cm, showed a high linear correlation coefficient (r = 0.990865), being CN = (0.3027 × CR) + 0.4491, r² = 0.9818, the equation that describes the behavior between the variables for this length interval. In conclusion, in Nellore cattle, the transuterine migration of conceptus may not exist, or consists of a rare event. In addition, the sex ratio and predilection are not distinguished from the symmetrical distribution, and regarding fetometry, an equation that involves CR and CN, could be useful for the veterinary field routine, especially in reproductive evaluation.

Ultrasonographic diagnosis of early pregnancy in cattle using different ultrasound systems

OBJECTIVE

To evaluate the efficiency of different ultrasound devices in achieving an early diagnosis of pregnancy in dairy herds.

MATERIAL AND METHODS

A total of 1976 Holstein Friesian cows and heifers were artificially inseminated (AI) according to the herd manager's regime. Pregnancy diagnostics were performed between day 26 and 35 after AI using six different types of ultrasound systems (linear vs. sector scanners). Manual rectal palpation between day 45 and 60 after AI was used as the gold standard for pregnancy diagnostics. Sensitivity (SENS), specificity (SPEC), positive (PPV) and negative predictive value (NPV) and diagnostic accuracy (ACC) of the diagnostic measures were determined.

RESULTS

Average SENS was 82% (range 67.7-95.2%) with a mean SPEC of 73% (range 50.0-81.0%). ACC was 78.2% with a minimum of 64.6% and a maximum of 89.4%, depending on the ultrasound system. The PPV (ratio of the number of pregnant cows with a positive examination result to the number of cows actually pregnant) was 80.8% (range 59.1-88.1%), whereas the NPV (defined as the ratio of the number of cows correctly diagnosed negative to the number of cows actually open) was 74.4% (72.3-91.9%). Significant differences for these parameters were found depending on the ultrasound system used (p ≤ 0.01; Cramer's V. = 0.14).

CONCLUSION AND CLINICAL RELEVANCE

Regardless of the ultrasound device used, early pregnancy diagnostics between day 26 and 35 show a moderate diagnostic efficiency. Comparing the accuracy of the different devices, there may be a significant influence of type and technical parameters. Even though ultrasound systems with mechanical sector probes are not as convenient to use as systems with linear probes, according to this study, sector scanners are a reasonable alternative.

Management of Dairy Animals: Buffalo: Asia

Domestic buffaloes (Bubalus bubalis) of swamp type (for draught) and river type (for milk) dominate the tropical Asia with slightly more than 169.4 million. They breed throughout the year and produce two calves every 3 years and are fed mainly on straw, crop residues, and mineral supplements. Assisted reproductive technologies such as artificial insemination and embryo transfer have also been introduced and implemented in buffalo production with less success due to difficulty in detecting estrus. Providing good feed and feeding remain a challenge in buffalo husbandry due to limited feed resources. With improved management and proper breeding, the milk production from buffaloes has increased from 1500 to 5000 l per lactation. The river type buffalo currently produces about 73.2 million tonnes of milk annually.

Early pregnancy diagnosis in bovines: current status and future directions

An early and accurate diagnosis of reproductive dysfunctions or aberrations is crucial to better reproductive management in livestock. High reproductive efficiency is a prerequisite for high life-time production in dairy animals. Early pregnancy diagnosis is key to shorten the calving interval through early identification of open animals and their timely treatment and rebreeding so as to maintain a postpartum barren interval close to 60 days. A buffalo, the most important dairy animal in the Indian subcontinent, is known for problems related to high calving interval, late puberty, and high incidence of anestrus. Lack of reliable cow-side early pregnancy diagnosis methods further aggravates the situation. Several methods of pregnancy diagnosis are being practiced in bovine species, yet none qualifies as the ideal pregnancy diagnosis method due to the inherent limitations of sensitivity, accuracy, specificity, speed, and ease of performing the test. The advancement of molecular techniques like proteomics and their applications in animal research has given a new hope to look for pregnancy biomarker molecules in these animals. This review attempts to examine common pregnancy diagnosis methods available for dairy animals, while assessing the usefulness of the modern technologies in detecting novel pregnancy markers and designing future strategies for research in this area.

HUSBANDRY OF DAIRY ANIMALS | Buffalo: Asia

Domestic buffaloes (Bubalus bubalis) of swamp type (for draught) and river type (for milk) dominate the tropical Asia with slightly more than 169.4 million. They breed throughout the year and produce two calves every 3 years and are fed mainly on straw, crop residues, and mineral supplements. Assisted reproductive technologies such as artificial insemination and embryo transfer have also been introduced and implemented in buffalo production with less success due to difficulty in detecting estrus. Providing good feed and feeding remain a challenge in buffalo husbandry due to limited feed resources. With improved management and proper breeding, the milk production from buffaloes has increased from 1500 to 5000 l per lactation. The river type buffalo currently produces about 73.2 million tonnes of milk annually.

Rainfall-driven sex-ratio genes in African buffalo suggested by correlations between Y-chromosomal haplotype frequencies and foetal sex ratio

Background

The Y-chromosomal diversity in the African buffalo (Syncerus caffer) population of Kruger National Park (KNP) is characterized by rainfall-driven haplotype frequency shifts between year cohorts. Stable Y-chromosomal polymorphism is difficult to reconcile with haplotype frequency variations without assuming frequency-dependent selection or specific interactions in the population dynamics of X- and Y-chromosomal genes, since otherwise the fittest haplotype would inevitably sweep to fixation. Stable Y-chromosomal polymorphism due one of these factors only seems possible when there are Y-chromosomal distorters of an equal sex ratio, which act by negatively affecting X-gametes, or Y-chromosomal suppressors of a female-biased sex ratio. These sex-ratio (SR) genes modify (suppress) gamete transmission in their own favour at a fitness cost, allowing for stable polymorphism.

Results

Here we show temporal correlations between Y-chromosomal haplotype frequencies and foetal sex ratios in the KNP buffalo population, suggesting SR genes. Frequencies varied by a factor of five; too high to be alternatively explained by Y-chromosomal effects on pregnancy loss. Sex ratios were male-biased during wet and female-biased during dry periods (male proportion: 0.47-0.53), seasonally and annually. Both wet and dry periods were associated with a specific haplotype indicating a SR distorter and SR suppressor, respectively.

Conclusions

The distinctive properties suggested for explaining Y-chromosomal polymorphism in African buffalo may not be restricted to this species alone. SR genes may play a broader and largely overlooked role in mammalian sex-ratio variation.