Growth, physiology, and coccidiosis infestation of suckling beef calves grazing warm-season grasses and offered creep-feeding supplementation with or without monensin.

This study evaluated the growth, physiology, and coccidiosis infestation of suckling beef calves provided monensin and grazing limpograss (Exp. 1) or bahiagrass (Exp. 2) pastures. Treatments were randomly assigned to pastures (4 pastures/treatment; 3 cow-calf pairs/pasture in Exp. 1; 4 pastures/treatment; 10 cow-calf pairs/pair of pastures in Exp. 2) and comprised of supplementation of 0.40 kg/d of soybean meal added or not with monensin (20 mg/kg of total DM intake) for 112 and 78 days before weaning in Exp. 1 and 2, respectively. In Exp. 1, supplement DM disappearance tended (P = 0.10) to be less for calves supplemented with vs. without monensin, but treatment × day and treatment effects were not observed (P ≥ 0.18) for herbage mass (HM), herbage allowance (HA), cow body condition score (BCS), calf average daily gain (ADG), calf plasma data, and fecal coccidia egg count. In Exp. 2, forage nutritive value, HM and HA, and cow BCS did not differ (P ≥ 0.43) between treatments. Supplemental monensin did not impact (P ≥ 0.78) plasma concentrations of insulin-like growth factor 1 but increased (P ≤ 0.05) calf overall ADG and plasma concentrations on day 78 and reduced plasma concentrations of urea nitrogen (PUN) on day 78 and fecal coccidia egg count on day 78 compared to calves provided no monensin supplementation. Hence, monensin supplementation successfully improved growth performance of creep-fed suckling beef calves, when herbage mass was not a limiting factor and coccidiosis infestation occurred.

Supplementation strategies for Nellore female calves in creep feeding to improve the performance: nutritional and metabolic responses.

The objective of this study was to evaluate the effects of supplementation strategy on performance, nutritional and metabolic characteristics of Nellore suckling female calves, on grazing Urochloa decumbens during the rainy-dry transition period. Forty-four Nellore female calves, averaging 147.6 ± 1.34 kg (4 months), were used. A single supplement 20% of crude protein of dry matter was provided, consisting of daily supplement at 0.0, 0.2, 0.4, or 0.6% of body weight. A positive linear effect (P < 0.05) on final body weight and average weight gain of female calves was observed with increased supplementation. Supplementation increased consumption, in kilograms per day, of dry matter (DM), organic matter (OM), crude protein (CP), digested dry matter, and total digestible nutrients (TDN), all calculated as % of dry matter. There was no effect of supplementation on the consumption in kilograms per day of neutral detergent fiber corrected for ash and protein (apNDF) (P > 0.05). Supplementation increased, in a quadratic way, the total apparent digestibility coefficient of DM, OM, CP, apNDF, and TDN (P < 0.05). There was no effect of supplementation (P > 0.05) on non-esterified fatty acid concentrations. There was a positive linear effect (P < 0.05) of supplementation on insulin concentrations. In this study, it is concluded that linearly increasing the feeding level of a supplement with 20% crude protein (% of DM) in the range of 0.2-0.6% of body weight improves the performance, nutritional and metabolic characteristics of the animals, considering these pasture characteristics.

Creep feeding effects on male Nellore calves influencing behavior and performance of their dams.

The objective of the present study was to evaluate the effect of different schemes of calves' supplementation in a creep feeding system, on the behavior of Bos indicus calves and dams, and also the influence of the calves' supplementation on dams' performance. Forty-eight Nellore male calves (147 ± 7 kg body weight and 3 months of age) in the suckling phase and their dams (476 ± 9 kg and 6 years of age) were studied in a completely randomized design. The experiment was divided into two periods of 71 days. The treatments were 5- and 10-g supplement dry matter (DM)/kg BW day offered in periods 1 and 2, respectively (5S/10S); 10- and 5-g supplement DM/kg BW day offered in periods 1 and 2, respectively (10S/5S); 7.5-g supplement DM/kg BW day in both periods 1 and 2 (7.5S); and mineral mix ad libitum in both periods 1 and 2 (MM). No differences (P < 0.05) in body condition score (BCS), final body weight (FBW), and average daily gain (ADG) were found in dams' performance. Calves from MM treatment spent more time (P < 0.05) grazing than the supplemented calves from 5S/10S and 10S/5S treatments, in the first period. No difference in suckling time was found between the treatments (P > 0.05) in the first evaluated period. Calves from 10S/5S treatment spent more time suckling and less time eating supplements (P < 0.05) than 5S/10S treatment animals, in the second evaluated period. Dams of MM treatment's calves had more idle time and lower grazing time when compared with the mothers of calves from 5S/10S and 10S/5S treatments. It was concluded that different schedules of Nellore calves' supplementation on pasture do not affect their mothers' performance, and supplementation decreases the grazing time of calves in the suckling phase.

Weight, body condition, milk production, and metabolism of Nellore cows when their calves are submitted to different supplementation levels.

Creep feeding has been used to reduce calves' nutritional dependence on the cow, but research results under tropical conditions have not been conclusive about the effects on the cow. Therefore, this study was conducted to evaluate the effects of high and low supplementation levels for Nellore heifer calves on performance, milk production, and metabolic profile of their mothers. Fifty multiparous Nellore cows and their respective calves were used. The following treatments were evaluated: 0-control, no supplement was fed to calves; 3-calves received supplement in the amount of 3 g/kg of body weight (BW); 6-calves received supplement in the amount of 6 g/kg of BW. There was no significant effect of level of supplementation offered to offspring on cow BW, body condition score (BCS) and subcutaneous fat thickness (P > 0.05). Level of supplementation of heifer calves did not significantly affect milk production corrected to 4% of fat (P > 0.05). Fat, protein, lactose, and total solids of the milk also did not differ among supplementation strategies (P > 0.05). Level of supplement fed to calves had no effect on cows' glucose, total cholesterol, HDL, LDL, triglycerides, total protein, and albumin levels (P > 0.05), but cows nursing calves that did not receive supplement had lower level of serum urea N (SUN; P < 0.05). We conclude that creep feeding in the amounts of 3 or 6 g/kg of BW daily has no major impact on dams' performance and metabolism.

Effects of milk replacer and starter diet provided as creep feed for suckling pigs on pre- and post-weaning growth.

This study was aimed at investigating the long-term effects of provision of liquid milk replacer (MR) and solid starter diet (SD) during lactation on post-weaning (PW) growth of pigs. In experiment 1, 33 cross-bred litters were allotted to four treatments: no supplement (CON), MR ad libitum, SD ad libitum and 100 g SD/litter/day from lactation day 4 through weaning at day 21 during late fall. In experiment 2, 40 litters received MR or none in July. PW pigs received commercial diets to marketing. In experiment 1, weaning weight (WW), pre-weaning average daily gain (ADG) and mortality (2.4%) were not influenced by creep-feeding MR or SD. ADG was greater (P < 0.05) in the MR group versus CON during days 21-54, but did not differ across the treatments during days 54-162. In experiment 2, ADG during lactation and WW were greater in the MR group versus CON, with mortality lower in the former (5.6 vs. 10.3%). However, PW ADG to day 175 did not differ between the two groups. Results suggest that creep-feeding MR or SD has no effect on PW growth. However, it remains possible that MR reduces PW mortality during the hot season.