Accuracy of assessment of luteal morphology and luteal blood flow for prediction of early pregnancy in goats.

This study aims to determine the best post-breeding time for an early pregnancy diagnosis in dairy goats, when using luteal morphology and vascularization assessment by B-Mode and color Doppler ultrasonography (US) in association or not with the anechoic uterine content. A total of 131 Saanen goats (2.0 ±â€¯0.5 years old) were used in the two studies. In the first study, pregnancy prediction was daily performed from Day 15-23 post-breeding in 51 does. This was based on a subjective assessment of luteal morphology (B-Mode US), luteal blood flow (color Doppler US), and the presence of anechoic uterine content (B-Mode US). In the second study, pregnancy predictions were performed in 71 does on the best post-breeding day, as determined in the first study (Day 21 using luteal blood-flow assessment and Day 23 using luteal morphological assessment and overall analysis). In both studies, pregnancy diagnosis was confirmed on Day 30 (gold standard method by B-Mode transrectal ultrasonography). The B-Mode and color Doppler US performance in reaching an early pregnancy diagnosis was evaluated by calculating sensitivity (Sens), specificity (Spec), negative and positive predictive values (NPV and PPV), accuracy (Acc), the Kappa index (κ), and the Younden index (J). In Study 1, the pregnancy prediction accuracy progressively increased from Day 17-23 using B-Mode US (D17: 50.98%; D18: 52.94%; D19: 62.75%; D20: 74.51%; D21: 86.27%; D22: 90.20%; D23: 96.08%), and from Day 17-21 using color Doppler US (D17: 49.02%; D18: 54.90%; D19: 70.59%; D20: 86.27%; D21: 96.08%). In the second study, color Doppler, B-Mode, and overall assessments at Day 21 and Day 23, respectively, presented a similar pattern of sensitivity, specificity, and accuracy as was found in the first study. Therefore, both color Doppler and B-Mode assessments can be judged as effective tools for reaching a pregnancy diagnosis in goats as early as on Day 21 and Day 23, respectively, post-breeding.

Morphological assessment of placentomal trophoblastic epithelium in the placenta of West African Dwarf goats: a light and electron microscopic study.

Gravid uteri harvested from 11 pregnant West African Dwarf goats at different stages of gestation were used to study the morphology of goat placentomal trophoblastic epithelium. The trophoblastic epithelium was composed of two trophoblast cell types; the mononucleate trophoblast cells and the binucleate trophoblast cells. Mononucleate trophoblast cells were tall columnar cells that rested on the basal lamina and extended to the foetomaternal interface, where their microvillar processes interdigitated with similar processes of the uterine epithelial cells to form the foetomaternal contact zone. Mononucleate trophoblast cells lining the arcade zones of placentomes contained erythrocytes in their cytoplasm. These cells are morphologically modified for acquisition of nutrients from the maternal compartment. Binucleate trophoblast cells showed two nuclei per cell and numerous characteristic membrane-bound granules in their cytoplasm. In addition, the binucleate cells resided in an intraepithelial position, showed evidence of capacity to migrate within the trophoblastic epithelium and fused with uterine epithelial cells at the foetomaternal interface. It would appear that the roles of the binucleate cells include formation of foetomaternal-derived hybrid cells in the placentomes and translocation of foetally synthesized substances across the placental barrier into maternal tissues via their migration and fusion with uterine epithelial cells. Furthermore this study demonstrated morphological modifications of the placentomal trophoblastic epithelium including extension of foetal blood capillaries into an intraepithelial position within the trophectoderm, such that they are situated close to the foetomaternal contact zone. This may enhance haemotrophic exchange of nutrients and metabolites between maternal and foetal blood circulations by reducing the diffusion distance between foetal and maternal blood capillaries.

Ultrasonographic assessment of early pregnancy diagnosis, fetometry and sex determination in goats.

This study was conducted to use B-mode trans-rectal (TR) and trans-abdominal (TA) ultrasonography to determine early pregnancy and fetometry as crown-rump-length (CRL) and bi-parietal-diameter (BPD). A total of 110 does aged between 8 and 36 months were used. The accuracy for detecting early pregnancy (fetal fluids and heartbeats) and fetal number (single or twins) was measured. The relationship between gestation age and CRL or BPD was determined from day 40 to 109 of gestation. The accuracy of fetal sexing was determined by differentiation of genital tubercle (GT) at different stages of gestation (from day 40 to 109 of gestation). The examination revealed 95.5% of examined does were pregnant, with accuracy 100% in detecting pregnancy for positive cases. The fetal number was 45.7% and 54.3% for single and twins+triplets, respectively. The TR probe enabled the reliable and earlier recognition of fetal fluid and heartbeats (indicating pregnancy) than TA probe. For maximum reliability, the TR observation of heartbeats is recommended as conclusive evidence of the presence of a live fetus. The TA convex probe was used from day 40 to 89 for measuring CRL and from day 40 to 109 for measuring the BPD. Gestation equations were: CRL=0.464x-17.767 and BPD=0.055x-1.431 (x=gestational age in days). The relation between gestational age and CRL or BPD was highly (p<0.0001) significant. The fetal sexing was found in 100, 83.3 and 64.3% of single pregnancies and in 85.7, 80 and 52.3% of twins+triplets pregnancies during 40-60 days, 61-70 days and 71-109 days of gestation, respectively. The accuracy of sex identification among the 3 groups was not significantly (p>0.05) higher in single than twins+triplets pregnancies. However, identification of GT in male fetus was possible from day 40 onward. From a total of 105 scanned does, 80 (76.25) were sexed. In conclusion, B-mode real-time ultrasonography is recommended as a reliable mean for early detection of gestation as early as 19-27 days after mating, for CRL or BPD measuring as well as fetal sex determination from day 40 of gestation onwards under field conditions.

Liveweight and chest girth correlation in commercial sheep and goat herds in Southwestern Nigeria / Correlación entre peso vivo y contorno del pecho en rebaños ovino y caprino comerciales en el Suroeste de Nigeria

The correlation between chest girth and weight of sheep and goats have been studied as a predictive guide in homestead farms where equipment to definitively quantify the weight of animals are unavailable and inaccessible. The livestock markets in the South Western part of Nigeria are still very underdeveloped and consist of peasant farmers taking their few animals to more developed areas to offer them for better prices to the consumer or middle men who are in the trade to attain the best profit. Twenty each of sheep and goats were randomly selected in herds from three different commercial locations and evaluated using weight and chest girth measurements as indices. Mean weight for the 3 groups of sheep was between 19.8 and 31.15kg, while for the 3 groups of goats was between 19.6 and 16.35kg. There was correlation (0.39-0.80) between sheep chest girth and weight which does not differ from those already established in literature and apredictive index of W= (18.9 +/- 0.36) CG where in more than 80 percent of the population are accounted for and in goats, correlation of 0.40-0.76 and a predictive index of W= (18.51 +/-0.31) CG where more than 76 percent of the population falls in. It was therefore concluded that chest girth is a useful tool in predicting weight of commercial sheep and goat.

La correlación entre la circunferencia de pecho y el peso de las ovejas y cabras ha sido estudiada como una guía de predicción en granjas, donde el equipo para cuantificar el peso de los animales no está disponible o es de difícil acceso. Los mercados de ganado en la parte sur-occidental de Nigeria, siguen siendo aún muy subdesarroliados y constan de campesinos que tienen pocos animales, a diferencia de zonas más desarrolladas, para ofrecer los mejores precios para el consumidor quienes están los comercializan para alcanzar el mejor beneficio. Veinte ovejas y veinte cabras fueron seleccionadas al azar entre los rebaños de tres diferentes localidades comerciales, y fueron evaluadas utilizando el peso y la circunferencia de pecho como los índices de mediciones. La media de peso de los 3 grupos de ovejas fue entre 19,8 y 31,15kg, respectivamente, mientras que para los 3 grupos de cabras fue entre 19,6 y 16,35kg. Hubo correlación (0,39-0,80) entre la circunferencia de pecho de las ovejas y el peso, que no difieren de las ya establecidas en la bibliografía y un índice predictivo de W = (18,9 +/- 0,36) CG en donde más del 80 por ciento de la población se contabilizan y en el ganado caprino, la correlación de 0,40-0,76 y un índice predictivo deW = (18,51 +/- 0,31)CG donde se encuentra más del 76 por ciento de la población. Por lo tanto, se llegó ala conclusión que la circunferencia de pecho es una herramienta útil en la predicción del peso vivo de las ovejas y cabras comerciales.

Masticatory motor patterns in ungulates: a quantitative assessment of jaw-muscle coordination in goats, alpacas and horses.

We investigated patterns of jaw-muscle coordination during rhythmic mastication in three species of ungulates displaying the marked transverse jaw movements typical of many large mammalian herbivores. In order to quantify consistent motor patterns during chewing, electromyograms were recorded from the superficial masseter, deep masseter, posterior temporalis and medial pterygoid muscles of goats, alpacas and horses. Timing differences between muscle pairs were evaluated in the context of an evolutionary model of jaw-muscle function. In this model, the closing and food reduction phases of mastication are primarily controlled by two distinct muscle groups, triplet I (balancing-side superficial masseter and medial pterygoid and working-side posterior temporalis) and triplet II (working-side superficial masseter and medial pterygoid and balancing-side posterior temporalis), and the asynchronous activity of the working- and balancing-side deep masseters. The three species differ in the extent to which the jaw muscles are coordinated as triplet I and triplet II. Alpacas, and to a lesser extent, goats, exhibit the triplet pattern whereas horses do not. In contrast, all three species show marked asynchrony of the working-side and balancing-side deep masseters, with jaw closing initiated by the working-side muscle and the balancing-side muscle firing much later during closing. However, goats differ from alpacas and horses in the timing of the balancing-side deep masseter relative to the triplet II muscles. This study highlights interspecific differences in the coordination of jaw muscles to influence transverse jaw movements and the production of bite force in herbivorous ungulates.

Accuracy of early fetal sex determination by ultrasonic assessment in goats.

The objective of this study was to determine the accuracy of early fetal sex determination by ultrasonic assessment of the relative location of the genital tubercle (GT) in goats at different stages of pregnancy as well as by the identification of fetal external genitalia. Pregnant animals were divided into three experimental groups (EI: n=21, EII: n=28, EIII: n=33). In EI, fetuses (n=27) were transrectally monitored daily from days 40 to 60 of pregnancy with a linear transducer (6.0 and 8.0MHz). In EII, fetuses (n=40) were examined once between days 45 and 70 of pregnancy by transrectal ultrasonography. In EIII fetuses (n=52) between days 100 and 120 of pregnancy, were submitted to a single transabdominal ultrasonography using a convex transducer (5.0 and 7.5MHz). Regardless of fetal sex diagnosis, 15/15 (EI), 13/16 (EII) and 9/14 (EIII) of single pregnancies and 10/12 (EI), 20/24 (EII) and 21/38 (EIII) of twin pregnancies were correctly identified. The accuracy of sex identification among EI (92.6%), EII (82.5%) and EIII (57.7%) was not statistically different (P>0.05). Identification of the GT in male fetuses was possible from day 45 onward. Changes in the GT position were not observed between days 53 and 60 of pregnancy. Accuracy of fetal sexing under field conditions is high in goats when ultrasound imaging is properly timed during pregnancy and when it is performed with proper equipment by experienced operators.

Predicting the energy cost of terrestrial locomotion: a test of the LiMb model in humans and quadrupeds.

The energy cost of terrestrial locomotion has been linked to the muscle forces generated to support body weight and swing the limbs. The LiMb model predicts these forces, and hence locomotor cost, as a function of limb length and basic kinematic variables. Here, I test this model in humans, goats and dogs in order to assess the performance of the LiMb model in predicting locomotor cost for bipeds and quadrupeds. Model predictions were compared to observed locomotor cost, measured via oxygen consumption, during treadmill trials performed over a range of speeds for both walking and running gaits. The LiMb model explained more of the variation in locomotor cost than other predictors, including contact time, Froude number and body mass. The LiMb model also accurately predicted the magnitude of vertical ground forces. Results suggest the LiMb model reliably links locomotor anatomy to force production and locomotor cost. Further, these data support the idea that limb length may underlie the scaling of locomotor cost for terrestrial animals.

Ultrasonic assessment of puerperal uterine involution in Balady goats.

Twenty-six postpartum Balady goats (primiparous, n=13; pluriparous, n=13) were used in this study. One animal of each group was slaughtered on postpartum days 1, 2, 4, 7, 10, 13, 19 and 25; in addition, three control nulliparous goats were slaughtered, and the genital tracts collected. Progress of uterine involution was monitored by repeated ultrasonographic measurements in live animals (primiparous n=6; pluriparous n=6) and measurement of the outer circumference of the uterine horns of slaughtered animals (primiparous n=8; pluriparous n=8). A consistent and progressive decrease in ultrasonographic and outer circumference measurements was found, although faster during the first 7 days postpartum than between days 7 and 19 postpartum. Uterine involution, assessed by the upper limit of the measurements in the nulliparous goats, followed a quadratic pattern and was completed by day 19 postpartum. Ultrasonographically, two elliptical-circular echogenic areas separated by an anechoic line of the stratum vascularis were depicted. Regressing caruncles and fluid in uterine lumen were recognized during the first week postpartum. Further analysis revealed a highly positive correlation between the outer circumference and ultrasonographic measurements. In conclusion, uterine involution in Balady goats was completed by day 19 postpartum and was unrelated to parity. The close association between ultrasound findings and macroscopic involution indicated that ultrasonography can dependably be used to monitor uterine involution under field conditions and can be a suitable alternative to animal slaughter for the study of uterine involution.