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The circadian rhythm alters forage chemical composition by balancing processes of photosynthesis, respiration, and transpiration. Timing of moving animals to a new paddock in a rotationally stocked system may take advantage of potential improvements in forage quality. The objective of this study was to collate available peer-reviewed papers aiming at comparing the forage quality and grazing dairy cattle performance when moved to a new paddock either in the morning (a.m.) or afternoon (p.m.). Twenty-four studies were gathered in total, and the number of observations per variable varied according to its availability within the studies. Among forage chemical composition parameters, contents of dry matter (DM), total nonstructural carbohydrates (TNC), soluble carbohydrates (SC), starch, neutral-detergent fiber (NDF), aciddetergent fiber (ADF), acid-detergent lignin (ADL), ether extract (EE), crude protein (CP), and digestibility were assessed. The animal performance parameters included dry matter intake (DMI), milk yield (MY), energy-corrected milk yield (ECM), milk fat (MF) and milk protein (MP) contents, fat yield (FY), and protein yield (PY). A meta-analysis was performed according to a random effects model weighted by inverse variance (Comprehensive Meta-Analysis V3.3.070). Means, standard deviations or p-values, and number of observations were used to compute the effect sizes. Heterogeneity between observed effect sizes was examined with the Cochran’s Q test and the I2 statistic. The standardized mean difference was reported with its 95% confidence interval (CI), where positive values indicate an increment of p.m. compared with a.m., and negative values indicate a reduction. Statistical differences were declared significant at P ≤ 0.05, and trends were declared at P ≤ 0.10. Forage sampled in the p.m. had greater (P < 0.001) contents of DM, TNC, SC, starch, and digestibility by 19.8, 16.3, 21.3, 12.1, and 1.0%, while NDF (P < 0.001), ADF (P < 0.001), ADL (P < 0.001), and CP (P < 0.01) were decreased by 1.8, 2.4, 2.4, and 1.7% relative to a.m. forage, respectively (Table 1). Content of EE was not influenced (P > 0.05) by time. The ECM was 3.4% greater (P < 0.001) and the PY tended to be 3.7% greater (P = 0.07) for dairy cows moved in the p.m. compared with those moved in the a.m (Table 2). Dry matter intake, MY, MF, MP, and FY were not affected (P > 0.05) by time. Results indicate that even with considerable improvements of forage nutritive value in the afternoon, the benefits in terms of animal performance are small. Future studies assessing potential benefits of moving animals to a new paddock during the afternoon, should consider statistical power analysis and sample size calculation when designing the experiment. [ABSTRACT FROM AUTHOR]

The objective of this study was to quantify the effects of ewe prolificacy potential (PP; predicted number of lambs born ewe-1 yr-1), as dictated by sire breed type, and stocking rate (SR; ewes ha-1) on ewe production efficiency (kg lamb live weight weaned:kg ewe live weight mated), lamb growth, lamb carcass output, and dry matter (DM; kg) and energy (UFL; unit of energy kg DM-1) consumption (in the form of both grazed and conserved herbage, concentrate supplementation, and total) in a temperate grass-based lamb production system. The study was a 2 × 3 factorial design, consisting of 2 differing ewe prolificacy potentials (medium prolificacy [MP]--Suffolk-sired crossbred ewes and high prolificacy [HP]--Belclare-sired crossbred ewes) and 3 stocking rates: low (LSR; 10 ewes ha-1), medium (MSR; 12 ewes ha-1), and high (HSR: 14 ewes ha-1). Each treatment was managed in a 5-paddock rotational system for the duration of the study. The HP treatment weaned more lambs ewe-1 and ha-1 (P < 0.01), yielded a higher average daily live weight gain (ADG) ha-1 (P < 0.001), produced an additional 50 kg of lamb carcass ha-1 (P < 0.05), and required 13% less DM and UFL to produce a kg of lamb carcass (P < 0.001) compared to the MP treatment. High prolificacy potential ewes had a 4% higher production efficiency (P < 0.05) than MP ewes. Ewe prolificacy potential had no effect on the total quantity of DM and UFL consumed ewe and lamb unit-1 (P > 0.05). Increasing stocking rate increased the number of lambs weaned ha-1 (P < 0.001) and increased lifetime lamb ADG ha-1 (P < 0.001). Lamb carcass output (kg) ha-1 was highest at the HSR, intermediate at the MSR, and lowest at the LSR (P < 0.001). The quantity of DM and UFL consumed ewe and lamb unit-1 and kg of lamb carcass-1 produced ha-1 increased as stocking rate increased (P < 0.001). In conclusion, results from this study demonstrate HP ewes to be more efficient in the production of lamb. Increasing stocking rate provides the opportunity to increase lamb carcass output ha-1; however, achieving this increase in output required additional DM and UFL ewe and lamb unit-1 above 12 ewes ha-1. [ABSTRACT FROM AUTHOR]

The article reports on study in which preweaning growth statistics were collected in four years on Braford-sired calves from Brahman-Hereford F1 females. It was observed that heifers with larger yearling heights had first calves which experienced faster growth to weaning for locations as well as all herbage allowances.

The objective of this experiment was to compare alternative forages and concentrate as buffer feeds offered to spring-calving dairy cows in the autumn. Ninety Holstein-Friesian cows were balanced on calving date and milk yield (19.9 ± 1.5 kg/cow/day) and randomly assigned to one of 6 treatments; (i) 17.5 kg of grass DM allowance (LG), (ii) 24 kg of grass DM allowance (HG), (iii) LG + 4 kg concentrate DM (C), (iv) LG + 4 kg maize silage DM (M), (v) LG + 4 kg urea-treated processed whole crop wheat DM (UPWCW) and (vi) LG + 4kg fermented whole crop wheat DM (FWCW). Treatments were imposed from 13 September to 7 November 2004 (2 grazing rotations). Both LG and HG herds grazed separately while the 4 supplemented treatments grazed together, as a single herd. The supplementary forages were group fed from a diet feeder after morning milking. Concentrates were offered individually in the milking parlour during am milking. Herbage removal rate was 18.7, 15.0 and 14.4 kg/cow/day (s.d. 2.65 kg) for HG, LG and supplemented herds, respectively. Animals supplemented with concentrate (18.3kg/cow) had a significantly (P<0.001) higher milk yield compared to the HG (15.5kg), M (15.0kg) and UPWCW (14.9) treatments, which in turn had a significantly greater milk yield than LG (13.2kg) and FWCW (14.2 kg). Solids corrected milk (SCM) yield was significantly (P<0.001) greater for C (+2.3kg) than HG (14.9), which was greater than M (14.5), UPWCW (14.3) and FWCW (13.8kg /cow), the LG herd (12.6kg /cow) had the lowest SCM yield. Milk fat, protein and lactose concentrations, as well as body condition score (BCS) and liveweight were not significantly different across treatments. The rennetability of milk tended to be higher in treatments M and FWCW while it was poorest in C. There is a large solidscorrected milk production benefit to supplementing grazing cows, on a restricted grass allowance in late lactation, with concentrate. Supplementing with other forages gave smaller responses, while extra herbage allocation proved superior. [ABSTRACT FROM AUTHOR]