Full-fat corn germ improves the performance and milk fat yield of Girolando cows fed sugarcane bagasse and cactus cladodes as forage sources.

We investigated the effects of replacing ground corn with full-fat corn germ (FFCG) on milk production, milk composition, and nutrient use in cows fed sugarcane bagasse and cactus cladodes. Ten multiparous Girolando cows (average body weight 500 ± 66 kg, 90 ± 15 days in milk) were distributed in a replicated 5 × 5 Latin Square and assigned to five dietary treatments containing 0%, 25%, 50%, 75%, or 100% of full-fat corn germ in substitution to ground corn. Full-fat corn germ increased fat-corrected milk yield by 2.2 kg/day and the synthesis of fat, lactose, and total solids in milk by 94.4, 60.0, and 201.10 g/day, respectively (p < 0.05). Cows fed corn germ quadratically increased (p < 0.05) dry matter intake by 1.01 kg/day, with the intake of crude protein and total digestible nutrients following the same pattern. Conversely, the substitution of corn for full-fat corn germ linearly reduced (p < 0.05) the total non-fiber carbohydrate intake from 5.79 to 4.40 kg/d. Except for ether extract and non-fiber carbohydrates, full-fat corn germ did not alter (p > 0.05) nutrient digestibility. Cows fed corn germ excreted less (p < 0.05) urea-N in milk and urine N. These results demonstrate that full-fat corn germ can partially replace ground corn to enhance the milk production efficiency of crossbred cows fed cactus cladodes and sugarcane bagasse. Furthermore, including sugarcane bagasse in FFCG-supplemented diets prevents milk fat depression in cows fed cactus cladodes.

Nutritional Quality of Milk Fat from Cows Fed Full-Fat Corn Germ in Diets Containing Cactus Opuntia and Sugarcane Bagasse as Forage Sources.

We evaluated the performance, milk composition, and milk fatty acid profile of cows fed diets composed of cactus cladodes (Opuntia stricta [Haw.] Haw), sugarcane bagasse and increasing levels of full-fat corn germ (FFCG). We hypothesized that ground corn can be effectively replaced by FFCG when cactus cladodes and sugarcane bagasse are used as forage sources. The cows were randomly distributed into two 5 × 5 Latin Squares and fed five diets in which ground corn was progressively replaced with full-fat corn germ (FFCG; 0%, 25%, 50%, 75%, or 100% of substitution). Adding FFCG to the diet increased milk production and milk fat content and reduced milk protein content. Overall, FFCG reduced the proportion of saturated FAs and increased mono- and polyunsaturated FAs in milk, including CLA isomers. In addition, activity indices of stearoyl-CoA desaturase were reduced by increasing levels of FFCG. We conclude that the substitution of corn for FFCG in diets based on cactus cladodes and sugarcane bagasse positively modifies the FA profile of milk and could add commercial value to milk products (e.g., CLA-enriched milk). In addition, the milk fat response indicates that the basal diet was favorable to the rumen environment, preventing the trans-10 shift commonly associated with milk fat depression.

Cactus Cladodes Opuntia or Nopalea and By-Product of Low Nutritional Value as Solutions to Forage Shortages in Semiarid Areas.

We aimed to evaluate the effect of the cactus cladodes Nopalea cochenillifera (L). Salm-Dyck. (NUB) and cactus cladodes Opuntia stricta (Haw.) Haw. (OUB), both combined with sugarcane bagasse (SB) plus urea, Tifton hay (TH), corn silage (CS), and sorghum silage (SS) plus urea on nutrient intake and digestibility, ruminal dynamics, and parameters. Five male sheep, fistulated in the rumen, were assigned in a 5 × 5 Latin square design. The NUB provided a higher intake of dry matter (DM) and any nutrients than SS. TH provided larger pools of DM and iNDF. The OUB and CS provided a higher DM degradation. CS provided a higher NDF degradation rate. OUB provided a lower ruminal pH. Depending on the collection time, the lowest pH value was estimated at 3.79 h after the morning feeding. There was an interaction between treatments and collection time on VFA concentrations. Due to the high degradation rate, greater energy intake, less change in rumen pH, greater volatile fatty acid production, and feasibility, we recommend using cactus associated with sugarcane bagasse plus urea in sheep diets.

Spineless Cactus plus Urea and Tifton-85 Hay: Maximizing the Digestible Organic Matter Intake, Ruminal Fermentation and Nitrogen Utilization of Wethers in Semi-Arid Regions.

The aim of this study was to evaluate the effect of replacing Tifton-85 hay (Cynodon spp. cv. Tifton 85) with 0, 150, 300, 450 and 600 g/kg dry matter (DM) of spineless cactus (SC, Nopalea cochenilifera Salm-Dyck) plus urea and ammonium sulfate (UAS; 9:1) on DM, digestible organic matter (DOM) and indigestible neutral detergent fiber (iNDF) intakes, as well as ruminal fermentation, N-balance, and microbial protein supply (MPS). Five rumen-fistulated and cannulated crossbred wethers, weighing 43.8 ± 5.80 kg, were randomized in a 5 × 5 Latin square design. Isonitrogenous diets (14% crude protein) were supplied with a roughage/concentrate ratio of 70:30. The DOM intake, N-retained, and MPS showed quadratic responses (p < 0.05), with maximum values estimated at the levels of SC+UAS of 414, 438 and 418 g/kg DM, respectively. Rumen pH and ammonia nitrogen, iNDF intake, N-urinary excretion, and serum urea and plasma ammonia reduced linearly (p < 0.05) with increasing SC+UAS inclusion. Ruminal acetate and propionate concentrations increased linearly with increasing SC+UAS inclusion. In wethers fed diets with a roughage/concentrate ratio of 70:30, roughage constituted of a SC+UAS/hay (Tifton-85) ratio of 41:29 is recommended in order to maximize the DOM intake, N-retention, and MPS.

Miúda (Nopalea cochenillifera (L.) Salm-Dyck)-The Best Forage Cactus Genotype for Feeding Lactating Dairy Cows in Semiarid Regions.

This study aimed to investigate the effects on nutrient intake and digestibility, milk yield (MY) and composition, milk fatty acids profile, and microbial protein synthesis caused by feeding lactating dairy cows four different forage cactus genotypes. Eight Girolando cows (5/8 Holstein × 3/8 Gyr), weighing 490 ± 69.0 kg (means ± standard deviation), and producing 15.5 ± 1.0 kg/d of milk during pretrial were distributed to two contemporaneous 4 × 4 Latin squares. The cows were fed a total mixed ration composed of sorghum silage (385 g/kg of dry matter (DM)), concentrated mix (175 g/kg DM), and forage cactus (440 g/kg DM). The experimental treatments consisted of different cactus genotypes, such as Gigante cactus (GC), Miúda cactus (MC), IPA Sertânia cactus (SC), and Orelha de Elefante Mexicana cactus (OEMC). The feeding of MC provided a higher intake of DM, organic matter (OM), and total digestible nutrients, as well as higher MY, energy-corrected milk, and microbial protein synthesis in comparison with those resulting from the other genotypes tested. The GC promoted lower DM and OM, and the apparent digestibility of neutral detergent fiber. The cows fed with OEMC showed lower MY and milk protein yield and content, and higher unsaturated over saturated fatty acid ratio in milk. Miúda forage cactus increased nutrient intake, digestibility of DM and OM, and microbial synthesis without impairing the milk fatty acid profile.

Nutritive Value, In Vitro Fermentation, and Methane Production of Cactus Cladodes, Sugarcane Bagasse, and Urea.

This study evaluated the effect of different roughages fed to sheep on nutrient and water intake, ingestive behavior, nitrogen balance, microbial protein synthesis, fermentation parameters, and methane production using an in vitro gas production system. The treatments consisted of five diets: cactus cladodes Nopalea (NUB) and Opuntia (OUB), both with the addition of sugarcane bagasse (SB) and urea/ammonium sulfate (urea/as); Tifton hay (TH); corn silage (CS); and sorghum silage (SS), also with added urea/as. The NUB provided greater (p ≤ 0.03) intakes of dry matter (1024 g/d), digestible organic matter (670 g/d), and crude protein (161 g/d) than those on the SS. The NUB provided greater (p < 0.01) dietary water intake (3023 g/d) than TH. The time spent on rumination was shorter (p < 0.01), and the idle time was longer in animals fed NUB and OUB than TH and CS. Microbial protein synthesis was not affected (p = 0.27). The final pH (6.4) of the incubation fluid and the concentration of NH3-N (39.05 mg/dL) were greater for NUB and OUB. Ruminal parameters and methane production were little or not affected by tested forages. We recommend using cactus cladodes in combination with sugarcane bagasse and urea/as in sheep diets.

Nutritional effects of using cactus cladodes (Opuntia stricta Haw Haw) to replace sorghum silage in sheep diet.

The aim of the present study was to evaluate the effects of replacing the sorghum silage in sheep diet with cactus cladodes [CC - Opuntia stricta (Haw) Haw] on dry matter and its compound intake and digestibility, feeding behavior, and nitrogen balance. The diets consisted of five replacement levels [0, 200, 400, 600, and 800 g/kg on a dry matter (DM) basis] and were formulated to be isonitrogenous [140 g/kg crude protein [CP], considering the ingredients' composition, with a roughage/concentrate ratio of 65:35, on a DM basis. Five uncastrated crossbred sheep, with an average body weight of 52.9 ± 6.0 kg, were assigned to a 5 × 5 Latin square. The trial lasted for 105 days with five consecutive 21-day periods, divided into 14-day adaptation and 7-day sampling periods. Dry matter (DM), organic matter, non-fiber carbohydrate (NFC), total digestible nutrient intake, and DM and NFC digestibility, increased (P ≤ 0.04) with the replacement of sorghum silage by CC. However, the time spent feeding and ruminating decreased, while idle time increased (P ≤ 0.03). Only feeding and rumination efficiency of DM improved (P ≤ 0.01) with the replacement, whereas feeding and rumination efficiency of neutral detergent fiber corrected to ash and protein did not. Nitrogen intake and nitrogen balance were not influenced, and urinary volume increased (P ≤ 0.01) with the addition of CC in the diet. In conclusion, we recommend replacing 80% of the sorghum silage with CC in sheep diets (with 35% concentrate), as CC was found to substantially increase the intake of nutrients, primarily energy.

Exogenous l-ARGININE does not stimulate production OF NO or cGMP within the rat corporal smooth muscle cells in culture.

BACKGROUND AND AIM: Nitric oxide (NO) is the intracellular chemical responsible for initiating a penile erection. Despite conflicting clinical data, it continues to be publicized and promoted that orally administered l-arginine, the putative substrate for NO, enhances the erectile response presumably by stimulating NO production by the corporal tissues resulting in an increase in cGMP production. To shed light on this issue, an in vitro study was conducted to explore the effect of direct exogenous administration of l-arginine as well as its precursor and metabolite, l-citrulline, on the NO-cGMP pathway within the cavernosal smooth muscle (CSM) cell. MATERIALS AND METHODS: CSM cells obtained from 8 to 10 week old Sprague-Dawley rats were grown in Dulbecco media with 20% fetal calf serum and then incubated with or without l-arginine (L-ARG) or l-citrulline (L-CIT) in a time course and dose-response manner. Sildenafil (0.4 mM), IBMX (1 mM), l-NAME (3 µM), ODQ (5 µM) and Deta Nonoate (10 µM) were used as either inhibitors or stimulators of the NO-cGMP pathway. mRNA and protein were extracted and used for the determination of the phosphodiesterase 5 (PDE5). PDE5 activity was determined by luminometry. cGMP content was determined by ELISA. Nitrite formation, an indicator of NO production, was measured in the cell culture media by a colorimetric assay. The cationic (CAT-1) and neutral (SNAT-1) amino acid transporters for L-ARG and L-CIT, respectively, were determined by Western blot. RESULTS: When compared to untreated CSM cells, incubation with 0.25-4.0 mM of L-ARG or 0.3-4.8 mM of L-CIT anywhere between 3 and 24 h did not result in any additional nitrite or cGMP production. The addition of l-NAME, IBMX or ODQ to these L-ARG and L-CIT treated cells did not alter these results. L-CIT but not L-ARG increased PDE5 mRNA and protein content as well as the activity of the PDE5 enzyme. Both CAT-1 and SNAT-1 were expressed in the CSM cells. CONCLUSIONS: This in vitro study demonstrates that exogenous administration of L-ARG or L-CIT failed to stimulate production of either NO or cGMP by the corporal CSM cells. A re-evaluation of the presumptive role of the exogenous administration of L-ARG in improving the synthesis of NO at least at the level of the CSM cells appears warranted.

Suplementación parenteral con cobre y zinc en bovinos Brahman en crecimiento en la región sur occidental de Venezuela / Copper and Zinc Parenteral Supplementation in Growing Brahman Cattle in the West-Southern region of Venezuela

Con el objetivo de evaluar el efecto de la suplementación parenteral con cobre y zinc sobre la ganancia de peso (GDP), incremento en medidas corporales y variables hematológicas, se utilizaron hembras (n=33) y machos (n=34) Brahman con un peso de 165 y 186 kg, respectivamente, los cuales fueron reagrupados y asignados a cuatro tipos de suplementación de ambos sexos cada uno: 1) suplementación mineral oral (SMO); 2) SMO más cobre inyectado (SMO-Cu); 3) SMO más zinc inyectado (SMOZn); y 4) SMO más cobre y zinc inyectados (SMO-Cu-Zn). El suplemento mineral oral (50 g/animal/día) contenía 500 ppm de Cu y 2.200 ppm de Zn. El Cu y Zn se suministraron por vía parenteral subcutánea al inicio del experimento, en una dosis única de 50 y 57,35 mg/100 kg de PV, respectivamente. Cada 28 días se registró el peso y se tomaron muestras de sangre, para hematocrito (Hct) y hemoglobina (Hb). Se midió la altura a la cruz (AC), altura a la grupa (AG) y perímetro torácico (PT), al inicio y al final del experimento. Este tuvo una duración de 120 días entre diciembre y abril. Los animales se manejaron bajo pastoreo rotacional en potreros de Brachiaria decumbens y B. humidicola, con una carga animal promedio de 1,22 UA/ha. La GDP no fue afectada por los tratamientos con un valor promedio global de 101,1 g/animal/día. Los grupos no inyectados con zinc tuvieron mayor incremento de AC (5,1 cm) que los restantes grupos (P<0,05). Los incrementos en AG y PT no fueron afectados por los tratamientos, con medias de 4,83 y 6,53 cm, respectivamente. Se concluye que la suplementación mineral parenteral no mejoró la GDP y los incrementos en medidas corporales, bajo las condiciones experimentales descritas, cuando los animales consumían forrajes bajos en proteína y ligeramente elevados en Fe y Mn.

In order to evaluate the effect of Copper and Zinc parenteral supplementation on average daily gain (ADG), increases in body measurements and hematological values, growing Brahman females (n = 33) and males (n = 34) were used, with body weight of 165 and 186 kg respectively, which were grouped into four sets of both sexes and assigned to four types of supplementation: 1) oral mineral supplementation (OMS), 2) OMS and copper injected (OMS-Cu), 3) OMS and zinc injected (OMS-Zn), and 4) OMS, copper and zinc injected (OMS-Cu-Zn). The oral mineral supplement (50 g/animal/day) contained 500 ppm Cu and 2,200 ppm Zn. Copper and Zn were applied by subcutaneous injection at the beginning of the experiment in a single dose of 50 and 57.35 mg/100 kg of BW, respectively. Every 28 days, body weight was recorded and blood samples were taken for hematocrit (Hct) and hemoglobin (Hb) analysis. Wither height (WH), hip height (HH) and girth chest (GC) were measured at the beginning and end of the experiment. The experiment lasted 120 days between December and April. The animals were managed under rotational grazing in pastures of Brachiaria decumbens and B. humidicola, with a stocking rate of 1.22 AU/ha. Average daily gain was not affected by treatments with an overall average value of 101.1 g/animal/day. The groups with no Zn injected had a greater increase in WH (5.1 cm) than the other groups (P<0.05). The increases in HH and GC were not affected by treatments, with averages of 4.83 and 6.53 cm, respectively. It is concluded that parenteral mineral supplementation did not improve ADG and increases in body measurements, under the experimental conditions described, when animals consume forages low in protein and slightly higher in Fe and Mn.