Resumen El objetivo del estudio fue comparar el efecto de dispositivos intravaginales liberadores de progesterona natural (CIDR) nuevos y reutilizados en protocolos de 6 días sobre el desempeño reproductivo y en las concentraciones de progesterona en suero sanguíneo de ovejas multíparas. Un total de 172 ovejas con peso corporal promedio de 59 kg se distribuyeron al azar en cuatro tratamientos: CIDR1 (grupo testigo con dispositivos nuevos) y CIDR2, CIDR3, CIDR4 (con 6, 12 y 18 días de uso, respectivamente). En cuanto al inicio de estro, hubo diferencia (P≤0.05) únicamente entre el tratamiento con CIDR nuevos (40 ± 10 h) y CIDR de segundo uso (31 ± 9 h). En las variables presencia de estro, porcentaje de gestación, porcentaje de fertilidad y tipo de parto no se obtuvieron diferencias significativas (P>0.05) entre tratamientos. La presencia de estro osciló entre 93 y 100 %, el valor promedio de gestación fue 80.8 %, 80.2 % para fertilidad y 1.26 para el índice de prolificidad. Los porcentajes de partos sencillos fueron mayores (P≤0.05) a los partos dobles en los cuatro tratamientos. Se concluye que el uso de CIDR en protocolos de 6 días permite que los dispositivos sean utilizados hasta por cuatro ocasiones con buenos resultados.

Abstract Estrus synchronization( is a vital strategy in sheep production and is accomplished most often via controlled internal drug release (CIDR) devices. Reuse of CIDR devices can reduce operating costs and ewe exposure to progesterone (P4), but remains controversial. A comparison was made of the effects of new and reused natural progesterone-releasing intravaginal (CIDR) devices in six-day protocols on reproductive performance variables and blood serum progesterone concentrations in multiparous ewes. A total of 172 sheep (average body weight = 59 kg) were randomly distributed into four treatments: CIDR1 (control group, new devices), CIDR2 (second-use), CIDR3 (third-use) and CIDR4 (fourth-use). The variables ewes in estrus, pregnancy rate, fertility rate and parturition type did not differ (P>0.05) between treatments. Estrus onset was later (P≤0.05) in CIDR1 (40 ± 10 h) than in CIDR2 (31 ± 9 h). Ewes in estrus ranged from 93 to 100 %, average pregnancy rate was 80.8 %, average fertility rate was 80.2 % and the prolificacy index was 1.26. The single delivery rate was higher (P≤0.05) than the double delivery rate in all four treatments. Intravaginal CIDR devices can be used in ewes up to four times in six-day estrus synchronization protocols without affecting reproductive variables.

Abstract: The aim was to evaluate the effect of dietary addition of a polyherbal phytogenic (Animunin) on the productive performance and blood biochemistry in finishing lambs. Forty Hampshire × Suffolk males lambs (initial body weight 26.52 ± 2.13 kg) were allocated according to a completely randomized design in four treatments. Treatments consisted of dietary inclusion of the Animunin at 0, 1, 2, and 3 g kg-1 dry matter (DM). Animunin addition was not modified (p > 0.05) the productive performance, DM intake, backfat thickness, chop area, energy and protein metabolites, or liver enzymes. While hematocrit, hemoglobin and erythrocytes showed a quadratic response (p ≤ 0.05) with Animunin. The polyherbal phytogenic evaluated did not improve lamb’s productive performance and metabolites related with immune response.

Resumen: El objetivo fue evaluar el efecto de la adición dietaría de un fitogénico poliherbal (Animunin) sobre el comportamiento productivo y la bioquímica sanguínea en corderos. Se utilizaron 40 corderos machos Hampshire × Suffolk con peso vivo inicial de 26.52 ± 2.13 kg, distribuidos en un diseño completamente al azar en cuatro tratamientos. Los tratamientos fueron la inclusión de Animunin a 0, 1, 2 y 3 g kg-1 de materia seca (MS). La adición de Animunin no modifico (p > 0.05) el comportamiento productivo, el consumo de MS, el espesor de grasa dorsal, el área de la chuleta, los metabolitos energéticos y proteicos, o las enzimas hepáticas. Mientras que el hematocrito, la hemoglobina y los eritrocitos mostraron una respuesta cuadrática (p ≤ 0.05) a la adición de Animunin. El fitogénico poliherbal no mejoró el comportamiento productivo ni los metabolitos relacionados con la respuesta inmune de corderos.

Resumen El objetivo de este estudio fue determinar el nivel máximo de inclusión de aceite de canola (AC) en dietas para cerdos en finalización, para incrementar el contenido de ácido oleico y ácidos grasos insaturados y mejorar la relación Ω6: Ω3 en la carne, sin afectar el comportamiento productivo, características de la canal y fisicoquímicas de la carne. Los tratamientos fueron: la sustitución gradual de aceite de soya (6%) por AC en dietas para cerdos en etapa de finalización I y II (0, 2, 4 y 6% de AC). Las unidades experimentales fueron 48 cerdos machos castrados con peso vivo inicial de 50.00 ± 4.5 kg, evaluados durante cuatro semanas en cada etapa. Con los datos obtenidos se realizó un ANDEVA y se detectaron tendencias lineales o cuadráticas (P≤0.10). En finalización I la ganancia de peso disminuyó con la inclusión de 2% de AC, aunque la incorporación de 2 y 4% de AC no tuvo efecto. En finalización II, un nivel entre 2-4% de AC redujo el consumo de alimento y mejoró la conversión alimenticia (P≤0.05). La adición de AC no modificó las características de la canal y no afectó las características fisicoquímicas de la carne (P≥0.10). El AC en la dieta aumentó la concentración de ácidos grasos monoinsaturados (AGMI) y ácido oleico (P≤0.05); redujo el ácido linoleico (P≤0.03), ácidos grasos poliinsaturados (P≤0.07) y la relación Ω6:Ω3 (P≤0.01). En conclusión, la adición de AC (2-6%) en la dieta de cerdos en finalización incrementa gradualmente el contenido de ácido oleico y de AGMI, además, mejora la relación Ω6:Ω3 en la carne de cerdo, sin afectar las variables productivas y la calidad de la carne.

Abstract The objective of this study was to determine the maximum level of inclusion of canola oil (CO) in diets for finishing pigs, to increase the content of oleic acid and unsaturated fatty acids and improve the Ω6:Ω3 ratio in meat, without affecting the productive performance, carcass characteristics and physicochemical characteristics of the meat. The treatments were: the gradual substitution of soybean oil (6 %) for CO in diets for pigs at finishing stage I and II (0, 2, 4 and 6 % of CO). The experimental units were 48 castrated pigs with initial live weight of 50.00 ± 4.5 kg, evaluated for four weeks at each stage. With the data obtained, an ANOVA was performed, and linear or quadratic trends were detected (P≤0.10). At finishing stage I, the average daily gain decreased with the inclusion of 2 % of CO, although the incorporation of 2 and 4 % of CO had no effect. At finishing stage II, a level between 2-4 % of CO reduced average daily feed intake and improved feed conversion (P≤0.05). The addition of CO did not modify the characteristics of the carcass and did not affect the physicochemical characteristics of the meat (P≥0.10). CO in the diet increased the concentration of monounsaturated fatty acids (MUFAs) and oleic acid (P≤0.05); it reduced linoleic acid (P≤0.03), polyunsaturated fatty acids (P≤0.07) and the Ω6:Ω3 ratio (P≤0.01). In conclusion, the addition of CO (2-6 %) in the diet of finishing pigs gradually increases the content of oleic acid and MUFAs, in addition, it improves the Ω6:Ω3 ratio in pork, without affecting the productive variables and the quality of the meat.

ABSTRACT The objective of the present research was to determine the effect of long synchronization protocols based on reused progesterone devices (controlled internal drug release [CIDR]) associated with different doses of equine chorionic gonadotropin (eCG) on reproductive variables in crossbred sheep (Suffolk × Kathadin × Dorset). The CIDR were used for eleven days in a previous study in sheep from the same herd and were washed and disinfected before reusing. Sixty-four sheep, in the reproductive season, were randomly assigned to four experimental groups (n = 16). Treatments consisted of a group with 10 d CIDR and 300 IU eCG; a group with 10 d CIDR and 400 IU of eCG; a group with 12 d CIDR and 300 IU of eCG; and a group with 12 d CIDR and 400 IU of eCG. A completely randomized design was used. There was an estrous presentation rate of 100% in all treatments. The begining of estrous, gestation rate, fertility rate, type of parturition, and prolificacy index were equal between groups. Progesterone serum concentration was higher in sheep from the 10 d CIDR groups. The CIDR, reused for the second time, associated with 300 or 400 IU of eCG for estrous synchronization in sheep, are effective to obtain good pregnancy rates and ensures higher prolificacy rates.

ABSTRACT We conducted an experiment to evaluate the effect of a polyherbal additive with metabolites such as antioxidants, vitamins, and small hydrolysable tannoids oils on productive parameters and blood metabolites in finishing lambs. Forty male Hampshire × Suffolk lambs (23.79±2.24 kg) were used in a completely randomized experimental design. Treatments consisted of dietary inclusion of a polyherbal additive based on Emblica officinalis and Ocimum sanctum at 0, 5, 10, and 15 g/kg dry matter for 60 d. There were no effects on daily gain, dry matter intake, feed conversion, back fat thickness, and Longissimus dorsi area; however, hot carcass dressing improved linearly as the level of herbal additive supplementation was increased. The antioxidants of the polyherbal additive linearly inhibited lipid oxidation of the meat (24 h; day 10) and improved its water-holding capacity (24 h). Meat lightness after 1 d was reduced linearly, but no changes were detected in other color parameters. Metabolites (glucose, urea, cholesterol) related to energy or protein metabolism were not affected by the herbal additive. Lymphocytes and basophiles were reduced linearly whereas monocytes and segmented neutrophils increased linearly for polyherbal additive. The inclusion of the polyherbal additive does not improve daily gain or feed efficiency in finishing lambs but improves the carcass dressing and antioxidant capacity of the meat.

Abstract: The objective of this research was to determine the optimum concentration of synthetic arginine (Arg) that should be added to diets of nursery pigs to improve the productive performance. The addition of five concentrations of synthetic Arg (0.0, 0.5, 1.0, 1.5 and 2.0%) in diets was evaluated with 40 hybrid (Yorkshire × Duroc × Pietrain) barrows, with average initial live weight of 8.72 ± 1.36 kg and 30 days of age. The design used was completely randomized with five treatments and eight repetitions. The data were analyzed with ANOVA and treatment means were compared with Tukey’s test (p ≤ 0.05). The addition of 0.5% Arg in the diet improved average daily feed intake, average daily gain and gain: feed ratio (p < 0.05). The plasma urea concentration increased with the addition of 2% Arg in the diet (p < 0.05).

Resúmen: El objetivo de esta investigación fue determinar la concentración óptima de arginina (Arg) sintética que se debe adicionar a dietas para cerdos en iniciación para mejorar el comportamiento productivo. En el experimento se evaluó la adición de cinco concentraciones de Arg sintética (0.0, 0.5, 1.0, 1.5 y 2.0%), con 40 cerdos híbridos castrados, con peso inicial promedio de 8.72 ± 1.36 kg y 30 días de edad. El diseño utilizado fue completamente al azar con cinco tratamientos. Los datos se analizaron con ANOVA y las medias de tratamientos se compararon con la prueba de Tukey (p ≤ 0.05). La adición a partir de 0.5% de Arg en la dieta mejoró el consumo de alimento, la ganancia de peso y la conversión alimenticia (p < 0.05). La concentración de urea en plasma se incrementó con la adición de 2% de Arg en la dieta (p < 0.05).

ABSTRACT An experiment was carried out to evaluate the effect of an herbal choline feed plant additive on the productive parameters and blood metabolites of finishing lambs. Forty male Hampshire × Suffolk lambs (initial body weight of 30.36±3.75 kg) were assigned according to a completely randomized design. Treatments consisted of dietary inclusion of the herbal additive BioCholine at 0, 3, 6, and 9 g/kg dry matter for 56 days. A linear response for herbal choline dose was observed for daily gain, final body weight, feed conversion, blood glucose, and blood phosphatidylcholine as herbal choline level was increased in the diet. Total protein, globulins, and low-density lipoproteins showed a quadratic effect, and there were no effects on intake, Longissimus dorsi area, back fat, blood cholesterol, triglycerides, high-density lipoproteins, or albumins. The inclusion of the herbal choline feed plant additive improved daily gain and feed efficiency of finishing lambs. The choline feed plant additive is a source that can be used to meet choline requirements in small ruminants, as demonstrated by blood phosphatidylcholine and lamb performance.

Abstract The objective was to evaluate the addition of xylanase in nursery pig diets with a high amount of wheat bran (WB) and two energy levels. Growth performance, carcass characteristics and plasma urea concentration were assessed. Forty-eight hybrid barrows were used (7.98 kg initial body weight and 28 d of age), allotted in a completely randomized design. Treatments (T) were: T1, control diet: 3350 Kcal; T2: 3275 Kcal + xylanase; T3: 3350 Kcal + xylanase; T4: 3350 Kcal + WB + xylanase; T5: 3275 Kcal + WB + xylanase; T6: 3350 + WB + xylanase. The variables were analyzed with ANOVA and treatment means were compared with Tukey's test (p ≤ 0.1). For average daily gain (ADG), average daily feed intake, final body weight and fat free lean gain (FFLG), better response was observed in pigs fed diets without WB (p ≤ 0.1) where xylanase compensated energy reduction. The inclusion of xylanase in WB diets reduced the ADG and final body weight (p ≤ 0.1). Supplementation with WB did not change backfat thickness, longissimus muscle area (LMA) and lean meat percentage (p > 0.1). The backfat thickness and LMA were not affected (p > 0.1) by reducing energy in diets without WB (p > 0.1). In conclusion, diets high in wheat bran content affect growth performance variables, but it is offset by the addition of xylanase, as long as the energy matrix is observed.

Resumen El objetivo fue evaluar la adición de xilanasas en dietas con alta cantidad de salvado de trigo (ST) y dos niveles de energía para cerdos en iniciación sobre la respuesta productiva, características de la canal y concentración de urea en plasma. Se utilizaron 48 cerdos híbridos castrados de 7.98 kg de peso inicial y 28 d de edad, distribuidos en un diseño completamente al azar. Los tratamientos (T) fueron: T1, dieta testigo: 3350 Kcal de EM kg-1; T2: 3275 Kcal de EM kg-1 + xilanasas; T3: 3350 Kcal de EM kg-1+ xilanasas; T4: 3350 Kcal de EM kg-1+ ST + xilanasas; T5: 3275 Kcal de EM kg-1+ ST + xilanasas; T6: 3350 de EM kg-1+ ST + xilanasas. Los datos se analizaron con ANOVA, las medias de los tratamientos se compararon con la prueba de Tukey (p ≤ 0.1). Para la ganancia de peso (GDP), consumo de alimento, peso final (PVF) y ganancia de carne magra (GCM) se observó mejor respuesta en cerdos alimentados sin ST (p ≤ 0.1); compensando las xilanasas la reducción de energía. La inclusión de xilanasas en dietas con ST redujo la GDP y el pVF (p ≤ 0.1). La inclusión de ST no modificó la grasa dorsal (GD), área del músculo longissimus (AML) y GCM (p > 0.1). La GD y AML no fueron afectadas al reducir la energía en las dietas sin ST (p > 0.1). Las dietas con alto contenido de salvado de trigo afectan las variables productivas; aunque se compensa con la adición de xilanasas mientras se respete la matriz energética.

The objective was to evaluate two levels of lysine and threonine for growing pigs on growth performance, carcass characteristics and plasma urea concentration. In experiment 1, 36 pigs were used with initial body weight of 27.65 ± 5.65 kg during four weeks, allotted in a completely randomized design with a factorial arrangement 2 (lysine: 0.83 and 0.93 %) with x 2 (threonine: 05.52 and 0.62 %). The variables were analized ANOVA and treatment means were compared with Tukey's test. There was not effect on the concentration of lysine and threonine in all variables (p > 0.05). In experiment 2, 35 pigs were used with initial body weight of 16.71 ± 7.85 kg during six weeks, were evaluated five levels of threonine (0.52, 0.62, 0.72, 0.82 and 0.92 %), distributed in a completely randomized design. Orthogonal contrasts were used to determine linear, quadratic and cubic effects to estimate the optimal biological level (OBL) for each variable. The NOB for average daily gain and feed consumption was 0.90 % digestible threonine. In experiment 1 and 2 the concentration of urea in plasma was modified by the amount of lysine and threonine in the diet (p < 0.05). We conclude that the most appropriate level of digestible lysine to diet is 0.83 % and 0.90 % digestible threonine.

El objetivo del trabajo fue evaluar dos niveles de lisina y treonina digestibles en cerdos en crecimiento, para analizar el comportamiento productivo, características de la canal y la concentración de urea en plasma. En el experimento 1 se utilizaron 36 cerdos con peso promedio inicial de 27.65 ± 5.65 kg durante cuatro semanas, distribuidos en un diseño completamente al azar con arreglo factorial 2x2, dos concentraciones de lisina: 0.83 y 0.93 % y treonina: 05.52 y 0.62 %, respectivamente. Con los datos se realizó un ANOVA y las medias de los tratamientos se compararon con la prueba de Tukey. No hubo efecto por la concentración de lisina y treonina en las variables (p > 0.05). En el experimento 2 se utilizaron 35 cerdos con peso promedio inicial de 16.71 ± 7.85 kg durante seis semanas para evaluar cinco niveles de treonina (0.52, 0.62, 0.72, 0.82 y 0.92 %), en un diseño completamente al azar. Se utilizaron contrastes ortogonales para detectar efectos lineales, cuadráticos y cúbicos para determinar el nivel óptimo biológico (NOB) para cada variable. El NOB para ganancia de peso y consumo de alimento fue 0.90 % de treonina digestible. En el experimento 1 y 2 la concentración de urea en plasma se modificó por la cantidad de lisina y treonina presentes en la dieta (p < 0.05). Se concluye que el nivel más adecuado de lisina digestible para dietas es de 0.83 % y de treonina digestible de 0.90 %.