The research was conducted on a commercial land plot from the ejido Granada, municipality of Matamoros, Coahuila, situated inside the Comarca Lagunera, from April to August 2015, in order to establish the effect of two fertilization sources – organic and inorganic, upon the nutritional quality of forage maize during the spring-summer cycle with a randomized block experimental design. T₁= Acadian soil +Acadian foliage (marine algae extracts) and T₂= Regional control, with 16 replications. The evaluated variables were the nutritional quality of forage maize and the milk production (L•t^-1 dry matter and L•ha^-1). Due to the effect of the evaluated treatments, statistical differences were registered, both for, nutritional values of forage maize, such as: neutral and acid detergent fiber, non-fiber carbohydrates, total digestible nutrients, total net energy for lactation and for milk production, in favor of organic fertilization. Therefore, it can be concluded that fertilizers of marine origin applied to forage maize increased both nutritional quality of forage maize and milk yield per ton of dry matter and per hectare of this forage.

This study aimed to assess the influence of the social rank of rams and quality of stimuli to ewes between dominant and subordinate Dorper rams joined to anestrus ewes. Social rank was evaluated for two days (ESR; n = 36); rams were exposed to estrogenized ewes in a competitive test. According to the reproductive response, anovulatory ewes (n = 76) were divided into two groups: LHRe (n = 38; ewes exposed to four low hierarchy rams (LHR)) and HHRe (n = 38; ewes exposed to four high hierarchy rams (HHR)). Regarding aggressive behaviors, HHR showed a higher (p < 0.05) proportion of rams showing threatening, knocking, and blocking behaviors than LHR. Appetitive behavior was higher (p < 0.05) in HHR than LHR rams (3576 ± 0.7 vs. 3054 ± 0.7 number of events). Consummatory sexual behavior was higher (p < 0.05) in HHR than LHR (499 ± 0.3 vs. 205 ± 0.1 number of events). Indicators of sexual inactivity (SRI) were similar between HHR and LHR (499 ± 0.3 vs. 433 ± 0.1; p > 0.05). The estrus response (>80%; p > 0.05) and ovarian response (70%, p > 0.05) were similar for both groups of ewes. It was concluded that LHR are equally effective as HHR in inducing sexual activity in ewes showing postpartum anestrus.

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.

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