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Feeding high-quality forage diets may lead to excessive weight gains and over-conditioning for dairy heifers. Restriction of energy density and dry matter intake by using low-energy forages, such as straw, is a good approach for controlling this problem. Alfalfa stems contain high fiber and moderate protein content and have the potential to be used to replace straw to reduce dietary energy. The objective of this study was to compare nutrient intakes, digestibilities, growth performance, and feeding behaviors of dairy heifers offered an alfalfa silage/corn silage high-energy diet (HE; 13.1% crude protein, 65.4% total digestible nutrients, 39.7% neutral detergent fiber) with 2 energy-diluted diets that replaced various proportions of the corn or alfalfa silages with either alfalfa stemlage (STM; 12.6% crude protein, 59.1% total digestible nutrients, 46.4% neutral detergent fiber) or chopped wheat straw (WS; 12.6% crude protein, 61.9% total digestible nutrients, 43.7% neutral detergent fiber). Seventy-two pregnant Holstein heifers (16.8 ± 1.3 mo) were stratified into 3 blocks (24 heifers/block) by initial body weight (light, 440 ± 18.0 kg; medium, 486 ± 18.6 kg; heavy, 534 ± 25.1 kg), with each block composed of 3 pens (8 heifers/pen), with diets assigned randomly to 1 pen within the block. Diets were offered in a 56-d feeding trial. Both dry matter intake and energy intake were decreased with the addition of low-energy forages to the diets, but no differences in dry matter intake were observed across diluted diets. Digestibility of dry matter, organic matter, neutral detergent fiber, and apparent N were greater for HE compared with diluted diets, and for WS compared with STM. Total body weight gain (74 vs. 56 kg) and average daily gain (1.32 vs. 1.00 kg/d) were greater for heifers offered HE compared with diluted diets. Feed efficiency tended to be less for heifers offered the diluted diets compared with HE (10.7 vs. 8.6 kg of feed/kg of gain). Heifers did not sort for or against particles when offered HE. However, increased sorting behavior was observed for diluted diets. Compared with ad libitum feeding dairy heifers a diet with high nutrient content forages (corn silage and alfalfa silage), use of diet diluted with alfalfa stemlage or wheat straw is an effective feeding management strategy to control total daily dry matter and energy intake by increasing gut fill, and maintain desirable body condition and growth rates, even though the diluted diets had greater sortability. [ABSTRACT FROM AUTHOR]

Two 73-day experiments were done on growing calves to evaluate the effect of different forage particle length of hay grass on standing time, drinking time, and social behavior. Hay grass level was changed by increasing and decreasing forage to concentrate ratio (F:C). Hay was the only source of fiber in the diet. In experiment 1, F:C were fed at full length (FL) hay in the total mix ration: low F:C (50% forage) with FL, high F:C (65% forage) with FL. In experiment 2, calves were fed the same total mix ration with same ingredients and nutrient composition but differing in particle length of hay: treatments were lower F:C (50% forage) with short length and higher F:C (65% forage) with short length. At the end of second month, 1 week of adaptation period was provided to allow adjustment of social and feeding behavior with pen mates. Four color cameras supported with infrared antinozzle technology were used to record standing, drinking, and social behaviors. In experiment 1, treatment and hour interaction was found for standing time ( P < 0.05). Longer standing time was observed for the ninth hour after feed delivery. Animals with low F:C showed longer standing time as compared with high F:C ( P < 0.05). Social behavior was altered with hour of observation ( P < 0.05). Social activity was highest during the first to third and ninth hours after feed delivery. In experiment 2, standing time was affected by hour of observation in both treatment groups ( P < 0.05). Drinking water intake was affected by dietary treatment ( P < 0.05). Longest drinking time was observed in the low F:C group. Social activity was highest during first to second and ninth hours after feed delivery ( P < 0.05). This study suggests that forage level should be carefully considered to promote normal behavior and positive welfare especially during the growing phase of fattening calves. [ABSTRACT FROM AUTHOR]

This experiment was conducted to investigate the effect of energy density (ED) in the close-up period and supplementation of extruded full-fat soybean (ESB) during the first 4 wk after parturition on intake, body weight (BW), metabolic status, and performance of dairy cows. Fifty-seven Chinese Holstein cows with similar parity, previous 305-d milk yield, and expected calving date were dried off at -60 d relative to parturition and fed the standard herd dry-cow diet until -21 d relative to parturition. Energy density at low (LED, 1.25 Mcal/kg), medium (MED, 1.41 Mcal/kg) or high (HED, 1.55 Mcal/kg) levels of the close-up diets and postpartum supplementation of ESB at 0 kg/d (control, CON) or 1.5 kg/d (TRT) were used in a 3 x 2 factorial arrangement. All cows received the same CON diet from wk 5 to wk 8. As ED increased in the close-up diet, cows had higher dry matter intake and gained more BW and body condition score, and consequently were in improved energy balance status during the prepartum period, but lost more BW and more body condition score during the first 8 wk of lactation. Compared with LED cows, HED cows had higher blood concentrations of insulin and glucose, and lower nonesterified fatty acids (NEFA) prepartum, but had lower insulin concentration, higher leptin concentration and tended to have higher NEFA concentration postpartum. Milk production was not affected by the prepartum ED, although HED cows produced approximately 2 kg/d less milk than MED and LED cows during early lactation. Postpartum ESB supplementation elevated blood glucagon concentration regardless of prepartum ED during the first 4 wk of lactation. Interactive effects between prepartum ED and postpartum ESB supplementation were observed in blood concentrations of insulin, NEFA, bilirubin, total protein, albumin, and globulin. During early lactation, TRT decreased globulin concentrations in MED cows, and reduced NEFA and bilirubin concentrations in HED cows. Compared with CON, TRT cows had higher yields of milk (34.32 vs. 36.53 kg/d), milk lactose (1.63 vs. 1.74 kg/d), and solids-nonfat (2.98 vs. 3.18 kg/d), tended to have a greater yield of milk protein (1.11 vs. 1.17 kg/d), but tended to have lower milk fat percentage (4.18 vs. 3.94%) during the first 4 wk of lactation. In conclusion, compared with feeding the HED diet, feeding the LED diet during the close-up dry period had positive carryover effects on metabolism and production during early lactation, and the MED diet showed no advantage over the LED diet. Extruded full-fat soybean supplementation during the first 4 wk of lactation had positive effects on postpartum metabolic status, especially for those receiving the MED or HED diet prepartum, and resulted in an overall improved milk production during early lactation. [ABSTRACT FROM AUTHOR]

A total of 182 beef samples were minced and divided into calibration set (n=140) and independent validation set (n=42). Calibration models of NIRS (1000-1800 nm) were built using partial least squares regression (PLSR) on the calibration set of samples. Both the coefficient of determination in calibration (R2C) and the coefficient of determination in prediction (R2P) were over 0.98 for all chemical compositions. The ratio performance deviation (RPD) was 17.37, 5.12 and 10.43 for fat, protein and moisture, respectively. The results of the present study indicate the outstanding ability of NIRS to predict chemical composition in beef. [ABSTRACT FROM AUTHOR]