Reproductive physiology with emphasis on endometrial cycles of woolly and uakari monkeys-A literature review.

The ability of a species to withstand human impact depends on its life history characteristics, including social, ranging, and reproductive activity. The genera Lagothrix and Cacajao are more susceptible to anthropic action than small-sized primates due to their slower life histories, more restricted geographical ranges, and lower population densities. This narrative literature review aimed to gather scientific information available from the last 60 years on the reproductive biology of females of the genera Lagothrix and Cacajao. Most studies on the genus Lagothrix, mainly focused on L. lagothricha and L. l. poeppigii, present important advances on reproductive strategies, reproductive productivity, functional morphology and physiology, including seasonality, sexual cycle, gestation and fetal development in captive and free-living populations. Contrary, there is much less known about the reproductive biology of the genus Cacajao, with studies on free-living C. calvus and C. melanocephalus highlighting reproductive behavior, and basic description of the sexual cycle, gestation, and lactation. Unfortunately, the morphology of the female genital organs is only described in C. calvus, and there is still scarce information about the menstrual activity and the placenta. This literature review encourages primatologists, morphophysiologists, reproductive specialists, and ecologists to conduct comprehensive studies of these species to better understand the gaps in knowledge about reproduction, their relationship with their environment, including climatic and social variables. Understanding the integrative reproductive biology of these species will be a clue for improving the assessment of the resilience capacity of free-living populations and, consequently, establishing more appropriate management programs, and for the development of ex situ management techniques for the conservation of the species.

Hematological and serum biochemistry evaluation in howler monkeys (Alouatta caraya) and capuchin monkeys (Sapajus apella): A comparative study.

BACKGROUND: Evaluation of blood parameters in captive non-human primates (NHPs) is crucial for monitoring their health and ensuring that their environment meets their physiological requirements. METHODS: We performed hemogram, serum biochemistry, and parasitological exams in 20 howler monkeys and 21 capuchin monkeys. RESULTS: In both species, over 50% of the individuals presented at least one parasite. There was a negative effect of age on red blood cell (RBC), white blood cell, platelets, total protein, globulin, and alkaline phosphatase, and a positive effect on the A:G ratio, gamma-glutamyl transferase, and mean platelet volume (MPV). Capuchin monkeys presented the highest platelets and alanine aminotransferase (ALT) values and howler monkeys presented the highest MPV, aspartate aminotransferase, ALT, amylase, glucose, bilirubin, and triglycerides values. We observed an interaction between species and sex on RBC, Htc, mean corpuscular hemoglobin concentration, and cholesterol. CONCLUSIONS: Species differences found in blood parameters may reflect differences in physiological adaptations associated with ecological and morphological traits and are clinically relevant for evaluating animal health and the suitability of breeding programs.

Ultrasound evaluation of fetal bone development in the collared (Pecari tajacu) and white-lipped peccary (Tayassu pecari).

The study of fetal development allows for evaluating the different strategies adopted by mammal species to maximize neonatal survival. Autonomous locomotion is fundamental for newborns to perform foraging activities and increases newborn survival from predation. In this study, we assess the gestational bone development of 53 collared (CP, Pecari tajacu) and 61 white-lipped (WLP, Tayassu pecari) peccaries, collected through the collaboration of subsistence hunters in the Amazon. The bone mineralization and biometry of the axial and appendicular skeleton were assessed by ultrasound examinations, and the timing of the main bone developmental events was calculated in relation to the total dorsal length (TDL) and the percentage of the total gestational period (GP). The first US signs of mineralization of the axial skeleton in CP and WLP were observed in fetuses with 3.4 cm (42 gestation days, 30% GPCP ) and 5.1 cm (51 gestation days, 32% GPWLP ). The early development of the appendicular skeleton was observed by the synchronic appearance of the mineralized scapula, humerus, radius, ulna, ilium, ischium, femur, tibia, and fibula at 36% GPCP (50 gestation days), and 35% GPWLP (56 gestation days). The pubis was mineralized in fetuses at 55% GPCP (75 gestation days) and 59% GPWLP (94 gestation days). The mineralization was observed in all autopod bones at 79% GPCP (109 gestation days) and 67% GPWLP (106 gestation days). All primary ossification centers in long bones of thoracic and pelvic limbs were mineralized in advanced fetuses (GPCP and GPWLP ≥75%). The mineralized patella was not observed in advanced fetuses in either species. Secondary ossification centers first appeared at the distal epiphysis of the femur in the CP (99 gestation days, 72% GPCP ) and the distal epiphysis of the radius, femur, and tibia in the WLP (106 gestation days, 67% GPWLP ). Advanced fetuses of CP and WLP presented 60% (15/25) and 68% (17/25) of the total secondary ossification centers observed present in the adult domestic pig, while newborns from the domestic pig presented 52% (13/25). The early intrauterine development of the skeletal system in both peccary species suggests a precocial development strategy, which likely correlates with neonatal ability to escape predators and reduces the dependence on parental care.

Fetal bone development in the lowland paca (Cuniculus paca, Rodentia, Cuniculidae) determined using ultrasonography.

Studying the timing of the main events of embryonic and fetal development may clarify the strategies adopted by species to maximize neonatal survival and the consequences of these events for their life history. This study describes bone development during the fetal phase of the lowland paca (Cuniculus paca), comparing it with other precocial or altricial species, and its relationship with the species' adaptive strategies. A total of 102 embryos/fetuses obtained over the course of 17 years through collaboration with local subsistence hunters in the Amazon were analyzed. Measurements of mineralization of the axial and appendicular skeletons were performed by ultrasonography using a 10-18-MHz linear transducer. The chronological order of occurrence of mineralization in relation to the total dorsal length (TDL) was: skull (TDL = 4.1 cm); vertebral bodies (TDL = 4.6 cm); scapula, humerus, radius, ulna, ilium, ischium, femur, tibia, and fibula (TDL = 6.7 cm); ribs (TDL = 7.8 cm); clavicle (TDL = 8.5 cm); metacarpi/metatarsi (TDL = 11 cm); phalanges (TDL = 15 cm); tarsus (TDL = 18 cm); patella (TDL = 23 cm); and carpus (TDL = 27.2 cm). Secondary ossification centers first appeared in the femoral distal epiphysis (TDL = 16.6 cm) and tibial proximal epiphysis (TDL = 18.4 cm). Advanced fetuses (TDL > 30 cm, 97% gestational period) presented mineralization in all primary and most secondary centers. Compared to other species, paca neonates have a well-developed skeletal system at birth, which is important for their independent postnatal locomotion. Our results may contribute to the monitoring of bone development in other wild species, helping us to understand their life history, and serving as parameters for comparisons between precocial and altricial mammals.