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Founded on a circular economy perspective, the possible effect of targeted supplementation with leftover feed from dairy cows (i.e., intensive system) upon the productive economic performance of crossbred–rangeland goats (i.e., extensive system) in northern arid Mexico was assessed. Multiparous goats (n = 38) with similar body condition score (BCS) and body weight (BW) were randomly assigned during the deep anestrus season (i.e., March–April, 25° N) into two groups: (1) the control-non-supplemented group (CONT; n = 19; BCS: 1.76 ± 0.06; BW: 44.3 ± 2.5 kg) and (2) the supplemented group (SUPL; n = 19; BCS: 1.76 ± 0.07; BW: 43.7 ± 1.8 kg). While the SUPL group received 400 g goat d−1 of dairy cow feed leftovers prior to grazing, both groups went daily to the rangeland (i.e., ≈8 h). The study considered an experimental period of 36 d with an experimental breeding of 11 d (d0–d10). Previously, on days −20, −10, −1 preceding the male-to-female interaction, the anovulatory status of goats was confirmed through ultrasonographic scanning. Prior to mating, the males were separated from goats and treated for a period of 3 weeks (i.e., every 3rd d) with testosterone (i.e., 50 mg i.m.). The response variables evaluated considered goats induced to estrus (GIE, %), goats ovulating (GO, %), ovulation rate (OR, units), pregnancy rate-1 (PRd36, %), pregnancy rate-2 (PRd50, %), embryo mortality-d50 (EMO, %), potential kidding index-d50 (PKId50,%), kid weight at birth simples (KWBS, kg), potential litter efficiency at birth (PLEB, kg), and potential litter efficiency at weaning (i.e., d21 post kidding), either expressed as kg head−1 (PLEW1) or USD head−1 (PLEW2). Although no differences (p > 0.05) occurred for GIE and PRd50, increases in the phenotypic expression of OR (1.42 vs. 0.73), PRd36 (68.4 vs. 36.8), EMO (23.0 vs. 0), PKId50 (74.7 vs. 26.8), and KWBS (4.1 vs. 3.3) occurred (p < 0.05) in the SUPL goats. To have a more integrative evaluation regarding the out-of-season reproductive outcomes, three bio-economic efficiency indices per goat exposed to males were generated: PLEB (4.3 vs. 0.6 kg), PLEW1-kg (7.7 vs. 3.1 kg), and PLEW2-USD (63.9 vs. 26.1 USD), which also favored (p < 0.05) to the SUPL goats. The last result occurred despite no differences (p > 0.05) regarding BW, BCS, and serum glucose concentrations between experimental groups. Furthermore, applying the main research outcomes from this specific study toward the large-scale goat production system in the Comarca Lagunera—one of the largest dairy goat production hubs in The Americas—denoted promising expectations, either from an economic or productive–reproductive standpoint. Certainly, goat producers from the region would increase their potential annual income just from the sale of kids by close to 250%; that is from MUSD 1.1 to 3.9. This result should reduce food insecurity and economic stress, as well as enhance the livelihoods of the goat keepers and their families. [ABSTRACT FROM AUTHOR]

Background: The use of reproductive biotechnologies in equine practice has shown that some stallions are subfertile, so ways to improve fertility have been sought. Objective: This study aimed to evaluate the effect of nutraceutical supplementation on improving semen quality in Quarter Horse stallions. Methods: Semen from six Quarter Horse stallions was assessed for 4 months every 20 days using the computer‐assisted semen analysis system. They were evaluated for 60 days before supplementation; then, the same stallions were re‐evaluated for 60 days with nutraceutical supplementation (30 g/day). Results: Volume showed no significant difference (p > 0.05) with nutraceuticals. Sperm concentration (10x6) was significantly higher with supplementation (339.4 ± 17.5 sperm/mL) than without supplementation (224.6 ± 19.9). Sperm abnormalities (%) were significantly (p < 0.05) lower with supplementation (14.3 ± 0.6) than without supplementation (19.1 ± 0.4). Sperm kinematic parameters, total motility (TM), progressive motility (PM), rectilinear velocity (VSL), the velocity of the trajectory (VAP) and curvilinear velocity (VCL), were significantly better with supplementation (p < 0.05). Conclusions: Based on the results, it is concluded that nutraceutical supplementation improved semen parameters in Quarter Horse stallions. [ABSTRACT FROM AUTHOR]

Simple Summary: The effect of social rank (i.e., low or high) in adult Dorper rams on sexual behavior, body condition score, seminal quality, and whole blood count was evaluated. The high-social-ranked Dorper rams displayed more sexual behaviors compared with low-social-ranked rams. In parallel, high-social-ranked rams had a higher body condition score and a larger ejaculate volume compared with low-social-ranked rams; they also showed an optimal health and wellness status, reflected by the whole blood count. Such behavioral, metabolic, sexual, seminal, and health advantages shown by the high-social-ranked Dorper rams must be taken into account to avoid reproductive failures. While there is still limited evidence on the role that social rank plays in out-of-season reproductive success, this study helps to better comprehend how social dominance is associated with male-to-male competitiveness, male-to-female sexual behavior, seminal quality, and blood cell components, and how their interaction with each other modulates and even determines out-of-season reproductive success in Dorper rams. Dorper rams (n = 24) were evaluated during the sexual resting season to determine their social rank (SR), either high (HSR) or low (LSR), under intensive management conditions in northern Mexico (25° N). Aggressive behaviors were quantified during male-to-male interactions, and appetitive and consummatory sexual behaviors during male-to-female interactions. Morphometric, live weight (LW), and body condition score (BCS) were recorded. During the early reproductive season, male-to-female behaviors were newly itemized simultaneously by seminal quality and quantity sampling. Finally, the dependent variables of the hemogram components were also quantified. Neither LW (61.25 ± 2.4 kg) nor morphometric variables differed between SR groups. However, BCS (2.25 vs. 2.66 u), sexual behaviors (i.e., approaches: 59.6 vs. 21.73 n, mating with ejaculation: 77.7 vs. 42.86 %, latency to ejaculation: 16.6 vs. 143.07 s), ejaculate volume (0.57 vs. 0.23 mL), and hemogram components favored the HSR rams (p < 0.05). Moreover, in their first male-to-female interaction, >50% of the LSR rams failed to display any sexual activity. HSR rams displayed a greater number of threatening behaviors, managing to displace LSR rams when exposed to estrus ewes during the male sexual resting season; more sexual behaviors; and an increased seminal volume in a non-live weight-dependent fashion. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to evaluate the effect of the stage of seasonal anestrus and breed on ovarian response in non-estrous cycling goats using a progesterone (P4) injection plus human chorionic gonadotropin (hCG)-based protocol. In Experiment 1, non-estrous cycling local Mexican goats were treated with 20 mg of P4 plus 100 IU of hCG injections 24 h apart during April (early anestrus, n = 13) or June (late anestrus, n = 12). The estrous response, interval from hCG-to-estrus, and interval to ovulation were not affected by season (P > 0.05). In addition, the size of the follicle from which ovulation occurred and the size of the corpus luteum were not different between the two stages of seasonal anestrus (P > 0.05). In Experiment 2, the estrous response was compared between multiparous non-estrous cycling local Mexican (n = 18) and Alpine (n = 19) goats in which stage of the estrous cycle was synchronized using the same P4+hCG protocol as in Experiment 1. Neither the onset of estrus nor the time of ovulation differed between breeds, and the estrus-to-ovulation interval also was similar for both breeds (P > 0.05). The diameter of the dominant follicle at the time of ovulation was similar between local and Alpine goats (P > 0.05). In addition, the pregnancy rate was not different for both local and Alpine goats (P > 0.05). In conclusion, results of this study indicate that the stage of seasonal anestrus or breed do not modify estrous and ovarian response in non-estrous cyclic goats synchronized with a P4 injection plus hCG-based protocol. [ABSTRACT FROM AUTHOR]