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Simple Summary: In the Americas, the Comarca Lagunera (CL), located in North-arid Mexico, concentrates one of the main dairy cattle hubs (>500,000 Holstein cows) managed under highly technified-industrial schemes. Dairy cows' nutrition is based on the use of total mixed rations; whereas feed rejection (i.e., 3–5%) has been observed, such feed-leftovers retain a high-pitched nutritional value. The CL also holds an emergent sheep industry, which exhibited the largest production value growth (i.e., >580%; 2010–2023). With that in mind and considering a circular economy perspective, we envisioned a research opportunity. Our working hypothesis states that a basal diet founded on such dairy cow feed-leftovers and aligned with short-term supplementation (i.e., 40 d) with Withania somnifera L. (Ashwagandha) will enhance some reproductive and behavioral outcomes in Black Belly rams. Such approach should bridge these two interesting animal production systems in the CL. Considering a circular economy perspective, this study evaluates the possible effect of targeted short-term supplementation with Withania somnifera L. (WS; Ashwagandha) on ram's seminal quality, socio-sexual behaviors, and blood constituents. Black Belly rams (n = 20) received a basal diet comprising feed-leftovers from dairy cows in the north-arid Mexico (i.e., Comarca Lagunera CL). The experimental units, with proven libido and fertility, were homogeneous in terms of age (3.41 ± 0.21 yr.), live weight (LW; 53.8 ± 3.3 kg), body condition (BC; 2.96 ± 0.01 units), initial sperm concentration (2387 ± 804 × 106), and viability (23.9 ± 15.6%). Rams were randomly assigned during the transition reproductive period (i.e., May to Jun; 25° NL) to three treatment groups: non-supplemented control group (CONT; n = 6), low WS-supplemented (LWS; i.e., 100 mg kg LW−1 d−1 × 40 d; n = 7), and high-WS-supplemented (HWS; i.e., 200 mg kg LW−1 d−1 × 40 d; n = 7). The basal leftover diet was offered twice daily (0700 and 1600 h); the experimental period (EP) lasted 47 d. No differences (p > 0.05) among treatments occurred regarding LW and BCS at the onset of the EP. Whereas the greater scrotal circumference (SCRC, cm) arose in the LWS and CONT rams, an increased ejaculated volume (VOLEJA, mL) occurred in the WS-rams. A total of 5/9 (i.e., 55%) appetitive and 3/3 (i.e., 100%) consummatory sexual behaviors favored (p < 0.05) the WS-rams, particularly the HWS rams, towards the final EP. The same was true (p < 0.05) regarding the hemogram variables white blood cell count (×109 cells L−1), hemoglobin concentration (g dL−1), and medium corpuscular volume (fL). This study, based on a rethink–reuse–reduce enquiry approach, enabled connectedness between two noteworthy animal systems in the CL: dairy cows and meat sheep schemes. Certainly, the use of dairy cow feed-leftovers aligned with the short-term supplementation with WS promoted enhanced testicular function, augmented seminal volume, and an increased sexual behavior in Black Belly rams in northern Mexico. Finally, while our research outcomes should enhance not only the resilience and sustainability of sheep production and the well-being of sheep-producers and their families, it may also embrace clinical translational applications. [ABSTRACT FROM AUTHOR]

The possible effect of body condition score (BCS) on ovarian function, sexual behavior, (i.e., females and males; appetitive and consummative), estrus, ovulation, and reproductive performance was investigated in crossbred dairy goats under extensive conditions. Based on their BCS, female goats (n = 48) were divided into two experimental groups, either with a low (LG; 1.0 ± 0.2 units; n = 26) or with a high BCS (HG: 2.5 ± 0.9 units; n = 22). Bucks n = 4; cc = 2.5. Female sexual behavior (i.e., acceptance of anogenital sniffing and approach, flight, and tail wagging) was higher in the HG (p < 0.05). In addition, bucks exposed to HG goats showed more approach and mounting attempts (p < 0.01). There were no significant differences (p > 0.05) between the groups in either the follicular diameter or size. Interestingly, although follicular volume, pregnancy rate, kidding rate, and total number of kids born alive were higher in the HG goats (p < 0.05), there were no significant differences (p < 0.05) in fetal mortality and prolificacy between the HG and LG goats. In addition, the response variables of female ovulation, total number of corpus luteum, ovulation rate, corpus luteum diameter, and luteal tissue volume were more favorable in the HG goats (p < 0.05). Our research results demonstrate that a higher BCS improves not only the reproductive responses, but also sexual behavior (i.e., female and male). Larger ovarian structures, higher ovulation rates, higher pregnancy and kidding rates, and higher prolificacy were observed in the HG goats managed under a marginal semiarid extensive production system. [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]

We determine whether Dorper rams treated with testosterone in the sexual resting season trigger both appetitive and consummatory sexual behaviors and sexual and reproductive outcomes in anestrous ewes at 26° North during March-April. Dorper rams (n = 12, 2.5 years) were randomly divided prior to mating in two groups: GT (treated group; n = 6), treated with testosterone propionate (25 mg i.m. every 3 days × 3 weeks) and GC (control group; n = 6), treated with saline. Thereafter, adult anovulatory Dorper ewes (n = 61) were exposed to the GT-rams while the other group (n = 60) was exposed to the GC-rams. Ram's appetitive sexual behavior was similar (50 %) in both groups, yet the GT-rams exerted 100 % of the consummatory sexual behavior. Sexual and reproductive outcomes of the anestrus females exposed to both male groups considered two phases: 0-15 and 16-25 days from exposure to males. Involved variables were: ewes in estrus, ewes ovulating, duration of estrus, pregnant ewes, and lambed ewes. All the average variables favored those ewes exposed to GT-males: ewes in estrus: 85 versus 40 %; ewes ovulating: 80 versus 53 %; duration of estrus: 37 versus 25 h; pregnant ewes: 60 versus 31 %, and lambed ewes: 57 versus 31 %. Results confirm that adult Dorper rams treated with exogenous testosterone had improved consummatory sexual behavior and induced increased ovulation and pregnancy rates when exposed to anestrus ewes. This feasible and inexpensive testosterone-based protocol through the male effect also enhanced both sexual and reproductive outcomes in previously anestrous Dorper ewes during the natural out-of-season. Results are important to speed up reproductive performance of sheep during the natural anestrous season at this latitude, while also they embrace interesting outcomes from a comparative sexual behavior stand point. [ABSTRACT FROM AUTHOR]

The high temperatures recorded during the summer season in hot regions compromise the reproductive capacity of domestic animals. In rams, heat stress (HS) causes in the body a series of physiological, metabolic, endocrine and molecular adjustments in order to maintain normothermia and survive; however, several of these changes are negatively associated with their fertility, mainly endocrine ones. HS in rams causes a decrease in blood testosterone concentrations through different mechanisms, and this is negatively reflected on the process of spermatogenesis and sexual behavior. Consequently, heat-stressed rams exhibit low seminal quality and libido; at the sperm level, structural and DNA damage has been observed. Given this situation, the use of HS mitigation strategies during the summer in sheep farms in hot regions is recommended, such as the use of shades in pens, administration of antioxidants or modifications in the diet. Therefore, the objective of this document is to review the current knowledge regarding the effect of HS on the thermoregulation and reproductive capacity of rams, as well as the application of strategies for its mitigation. [ABSTRACT FROM AUTHOR]