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- Proportions of protein and concentrate in diets for buffaloes and cows
affect neutral detergent fibre degradability
Abstract: The study was designed to compare low and high levels of protein, namely 90 and 147 g/kg of dietary dry matter, and to evaluate the effect of concentrate proportions on the in situ digestion kinetics of neutral detergent fibre in buffaloes and cows fed a low protein diet at maintenance intake level. In the first experiment, heifers and lactating females were offered a high protein diet. In the second, the performances of buffaloes and cows were compared when fed diets with low and high proportions of concentrate at low dietary protein level. At higher protein supply, the heifers showed a 6% unit increase in neutral detergent fibre degradability (NDFD) compared with lactating animals. Similarly, at a higher level of concentrate proportion, an 8% unit increase was observed in NDFD. In both experiments the comparison of buffaloes and cows was non-significant for NDFD. Those data that were pooled against the stage of development of both experiments for protein levels depicted a 13% unit increase in NDFD at high protein level compared with low level. At maintenance intake level, a high dietary crude protein or concentrate supply improved the in situ NDFD of tropical forages in buffaloes and cows, owing to the enhanced intake of NDF from concentrate and better synchronization of protein and energy availability in the rumen.
- Effect of ferulic acid on growth, digestibility, digestive enzyme
activity, immunity and antioxidant status of broilers
Abstract: This study was conducted to evaluate the effects of ferulic acid (FA) on the growth, nutrient digestibility, digestive enzyme activities, immunity and antioxidant status of broilers. Ninety-six one-day-old male Arbor Acres broilers were randomly divided into two groups with six replicates of eight birds each, including control group (CON) and FA group (80 mg/kg diet). The experiment included starter (days 1-21) and finisher (days 22-42) phases. Compared with CON, FA group had higher average daily weight gain (ADWG) and lower feed to gain ratio (F:G) in the starter phase, and higher average daily feed intake (ADFI) in the finisher phase. The digestibility of dry matter (DM), organic matter (OM), crude protein (CP) and ether extract (EE) were higher in FA-fed broilers in days 19-21, but DM, OM and EE digestibility were lower in days 40-42. Ferulic acid treatment increased duodenal trypsin and jejunal amylase activity on day 21, but decreased duodenal trypsin, chymotrypsin activities and jejunal lipase activity on day 42. FA supplementation increased serum immunoglobulin M (IgM) and tumour necrosis factor-α (TNF-α) concentrations on day 21. Ferulic acid-fed broilers had greater hepatic glutathione peroxidase (GSH-Px) activity and lower serum malondialdehyde (MDA) level on day 21. On day 42, the serum superoxide dismutase (SOD) activity, hepatic SOD and GSH-Px activities was decreased in FA group. In conclusion, FA as an exogenous antioxidant at dosage of 80 mg/kg diet enhanced growth performance via improvement of digestive enzyme activities, immunity and antioxidant status of broilers in starter phase.
- Predicting feed intake from weaning to maturity in South African sheep
reared on high-energy grain-based diets
Abstract: Feed intake models seldom take breed differences into account. This study investigated various approaches to describing and predicting the feed intake of certain breeds (Dohne Merino, Dormer, Dorper, Meatmaster, Merino, South African Mutton Merino (SAMM) and White Dorper). On weaning at 90 days old, four ram and four ewe lambs from each breed were housed under feedlot conditions and reared on a high-energy concentrate-based diet until they reached maturity at about 12 months. Bodyweight and feed intake were recorded weekly. Daily dry matter intake was modelled with bodyweight for each breed using a quadratic function. Feed intake increased to a peak and then tended to decrease as lambs neared maturity. Dormer lambs had the highest peak intake (2202.02 g/day) and Merinos the lowest (1558.8 g/day). However, this model accounted for less than 50% of the variation in the groups. Linear regressions of percentage intake of bodyweight (R² = 0.732) and cumulative feed intake with bodyweight (R = 0.941) were deemed more reliable in predicting voluntary feed intake. The change in feed conversion ratio was modelled with an exponential relationship. At 75 kg live weight, Dormer rams had the highest feed conversion ratio (20.44) and SAMM rams the lowest (6.48). Generally, lambs with larger frame sizes (Dormer, Dorper and SAMM) presented higher feed intakes at a given bodyweight than smaller-framed breeds. Dorper rams and SAMM lambs proved to have better lifetime feed efficiency than the earlier maturing breeds.
- Components and specific gravity of colostrum from Anatolian buffalo cows
and effects on growth of buffalo calves
Abstract: This study aimed to determine the relationship between specific gravity (SG) of colostrum and its components, namely dry matter, fat and protein, on the growth of Anatolian buffalo calves. The study used 62 Anatolian buffalo cows and their calves (32 females and 30 males). The SG of the colostrum was measured with a colostrometer™, and the components were analysed with a milk analyser after calving. A single value for analysis was obtained by taking the arithmetical mean of the SG values of the colostrum two hours after birth. The values were classified as below average (Group 1:
- Composition, nitrate and nitrite levels, and antioxidant activity of milk
from agroecological and conventional systems
Abstract: Agroecological dairy production systems are gaining attention worldwide. However, few studies have compared the quality of bovine milk produced in these systems with that produced in conventional dairy production systems. In view of the different farming practices, it was expected that milk quality would differ between systems. This study aimed to compare the quality of milk produced by cows raised in the two systems. Twelve conventional farms and 10 agroecological farms were evaluated. Milk samples were analysed for chemical composition, somatic cell count, nitrate and nitrite levels, and total antioxidant capacity (TAC), which was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. Mean somatic cell counts (SSC) were high for both agroecological systems (2.31 SCC/mL (log10)) and conventional systems (2.42 SCC/mL (log10)). Nitrate levels of milk in agroecological and conventional systems were 0.15 ± 0.03 and 0.17 ± 0.02 mg/L, and nitrite levels were 0.05 ± 0.03 and 0.07 ± 0.02 mg/L. The DPPH radical scavenging activity levels were 6.31 ± 0.55% and 6.64 ± 0.44% for agroecological and conventional systems. According to the ABTS method, TAC values were 6.63 ± 0.28% and 6.48 ± 0.20% for agroecological systems and conventional systems. Thus, although these systems adopted different farming practices, no significant differences were observed in milk composition, SCC, nitrate, nitrite, and TAC.
- Efficacy of Tragopogón graminifolius medicinal powder as an inulin source
for laying hens
Abstract: In an experiment, the efficacy of Tragopogon graminifolius (TG) plant powder as a medicinal supplement for laying hens was investigated. A total of 192 Hy-line (W36) hens that had been laying for 52 to 63 weeks, were used. They were allocated to four replicates of four treatments (12 birds per in each replicate) in a completely randomized design. Diets were formulated to contain 0%, 2%, 4% and 6% TG powder. Dietary augmentation with TG powder affected the production and blood indexes of laying hens significantly. Egg weight, egg production percentage, egg mass and feed intake were greatest and feed conversion ratio, high yolk colour index, and Haugh unit were best when the hens were supplemented with 6% TG powder. Eggshell thickness decreased when this high level of TG powder was used. The lowest blood white cell count was observed with 2% TG in the diet. The TG levels did not change the blood indexes meaningfully. Based on these results, the provision of TG to laying hens at up to 6% of their diet improved the production traits.
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Open Access journal
