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This study was conducted to investigate the effects of processing method (grinding vs. steam flaking) and increasing densities of steam-flaked barley grain on dry matter intake ( DMI), rumen pH and fermentation characteristics, digestibility of dry matter in the total digestive tract ( DDTT), and milk production of dairy cows. Eight multiparous mid-lactation Holstein cows averaging 103 ± 24 DIM, 44.5 ± 4.7 kg milk/day and weighing 611 ± 43 kg at the start of the experiment were used in a replicated 4 × 4 Latin square design with 21-day periods. Cows were fed diets consisting of ( DM basis) 23.8% corn silage, 13.5% chopped alfalfa hay and 62.7% concentrate. The dietary treatments were either ground barley ( GB) using a hammer mill or steam-flaked barley ( SFB) - varying density at 390, 340 or 290 g/l. Processing method ( GB vs. SFB) did not affect DMI (23.6 kg/day on average), DDTT (71.0% on average), milk yield (43.4 kg/day on average), milk components, rumen pH and molar proportions of acetate, propionate, butyrate and sorting activity. Ruminal isovalerate concentration tended (p = 0.06) to be higher for cows fed GB than those fed SFB-based diets. Decreasing the density of SFB from 390, 340 to 290 g/l tended to linearly increase DMI (p = 0.09), decrease total solids percentage of milk (p = 0.10) and linearly decreased milk urea nitrogen (12.8, 12.4 and 12.1 mg/dl; p = 0.04); also, the sorting index ( SI) of the particles retained on the 19.0-mm sieve without affecting the SI of the particles retained on 8.0-mm, 1.18-mm or passed through 1.18-mm sieve (p = 0.05). These results indicated the limited effects of processing method (grinding vs. steam flaking) and densities of SFB (390, 290 or 290 g/l) on cows' performance and feed utilization for dairy cows fed low-forage diets. Therefore, both processing methods could be recommended under current feeding conditions of dairy cows. [ABSTRACT FROM AUTHOR]

This study investigated physiological effects of pistachio by-products silage (PBPS) substituted in Holstein male calves diets and its effects on the growth performance. Twenty-four Holstein male calves (4-5 months of age and 155.6 ± 13.5 kg BW) were randomly assigned to one of four experimental diets ( n = 6); contained 0%, 6%, 12% and 18% of PBPS (DM basis) respectively. During a 6-month experiment, dry matter intake (DMI) and weight gain were recorded and blood and urine samples were collected at different times. Results showed that mean DMI was not affected by different levels of PBPS in diets. But the calves fed 6% PBPS had the highest average daily gain (p < 0.05) and the lowest feed conversion ratio (p < 0.05). The calves fed 12% and 18% PBPS had lower albumin, white blood cell, haemoglobin and packed cell volume (p < 0.05) than those fed other diets. However, other serum metabolites, complete blood count (CBC), insulin and liver enzymes were not affected by the experimental diets. The long-term feeding of PBPS at different levels had no significant effect (p > 0.05) on pH, specific gravity, the number of white and red blood cells and epithelial cells count in urine. The animals did not show any symptom of illness or toxicity during the experimental period and all of the blood and urine parameters were in a normal range. It was concluded that substitution of PBPS up to 18% of the total diet that provide up to 18.2 g/kg DM total tannin had no adverse effects for Holstein male calves. [ABSTRACT FROM AUTHOR]

Safflower seed has the highest concentration of linoleic acid among 80 oilseeds but little information exists on the effective use of SS for lactation cows. It was hypothesised that a diet supplemented with an Iranian SS variety (IL-111) in combination with fish oil (FO) would result in higher concentrations of trans-18:1 (including vaccenic acid) and conjugated linoleic acids in milk fat than feeding an unsupplemented control diet. Our objective was to determine the effects of feeding diets containing: (i) Control: (C); (ii) 25 g of roasted SS IL-111 (RSS); (iii) 20 g FO and (iv) 25 g RSS + 10 g FO (RSS + FO) per kilogram of dietary DM on feed intake, ruminal fermentation, milk production and fatty acid profile. Eight multiparous Holstein cows were used in a replicated 4 × 4 Latin square design study. The experiment had four periods of 21 days. Milk Fat percentage was lower (p < 0.01) with FO supplementation and averaged 19.0 and 21.5 g/kg milk with FO and RSS + FO compared with 30.3 and 32.5 g/kg with C and RSS. Feed intake also was lower (p < 0.01) with FO vs. C (23.1 vs. 24.5 kg/day) but feeding RSS resulted in greater feed intake compared with other treatments (26 kg/day). Despite lower feed intake with FO, milk production did not change from controls but feeding RSS + FO resulted in greater milk yield than controls (42.6 vs. 39.3 kg/day). Ruminal pH was greater (p < 0.01) in cows fed FO than other treatments. Supplemental FO alone or in combination with RSS resulted in dramatic increases (p < 0.01) in c9,t11-18:2 in milk fat (12.7 and 13.2 g/day vs. 5.8 and 7.02 with C and RSS). It was surprising to note that 25 g/kg RSS can improve feed intake. [ABSTRACT FROM AUTHOR]

Our objective was to study the relationships between colostral somatic cell counts (SCC, a criterion for mastitis severity at parturition) and early calf growth, blood indicators of immunity, and pre-weaning faecal and health states. Sixty-nine Holstein cows were assigned to three groups of greater ( n = 21, 5051 × 103), medium ( n = 38, 2138 × 103) and lower ( n = 10, 960 × 103) colostral SCC (per ml) in a completely randomized design. Calves received 2 l of colostrum on day 1, and jugular blood was sampled at birth, at 3 h after the first colostrum feeding and at 42 days of age for immunoglobulin G (IgG) measurements. Calves were fed transition milk from their dams until 3 days of age and whole milk from 4 to 60 days of age twice daily at 10% of body weight. Health status and faecal physical scores were recorded daily for 42 days. Increased colostral SCC was associated with increased serum IgG at parturition. Colostral pH increased and fat percentage decreased linearly with the rising SCC. Feeding colostrum with greater SCC was associated with reduced serum IgG concentrations at 3 h after first colostrum feeding, greater incidences of diarrhoea and compromised health status during the first 42 days of age, and reduced weaning weight gain, but had no effects on calf body length and withers height. Colostral volume and percentages of protein, lactose, solids-non-fat, total solids and IgG were comparable among groups. Results suggest a role for SCC, as an indicator of mastitis and colostral health quality, in affecting calf health. As a result of the novelty of calf health dependence on colostral SCC found, future studies to further characterize such relationships and to uncover or rule out possible mediators are required before colostral SCC could be recommended for routine on-farm use in managing dry cow and calf production. [ABSTRACT FROM AUTHOR]