scholarly journals Methodology affects measures of phosphorus availability in growing broilers: Effects of calcium feeding strategy and dietary adaptation period length on true ileal phosphorus digestibility and predicted endogenous phosphorus losses

2017 ◽  
Vol 96 (3) ◽  
pp. 611-621 ◽  
Author(s):  
K.R. Perryman ◽  
H.V. Masey O'Neill ◽  
M.R. Bedford ◽  
W.A. Dozier
1990 ◽  
Vol 259 (6) ◽  
pp. E835-E843 ◽  
Author(s):  
G. A. Zello ◽  
P. B. Pencharz ◽  
R. O. Ball

Phenylalanine metabolism was determined in 41 studies of adult males (n = 10) consuming an energy-sufficient diet and receiving graded levels of dietary phenylalanine and excess tyrosine (40 mg.kg-1.day-1). After a dietary adaptation period to either 4.2 or 14.0 mg.kg-1.day-1 of phenylalanine; flux, plasma concentration, oxidation, and conversion to tyrosine were measured at test phenylalanine intakes of 5, 7, 10, 14, 21, 28, or 60 mg.kg-1.day-1. Oxidation was low and constant (1.3 mumol.kg-1.h-1) at intakes at or below 10 mg.kg-1.day-1 and increased linearly above this level. Conversion to tyrosine was minimal (2.1%) at these intakes. Breakpoint analysis showed the phenylalanine requirement with excess tyrosine to be 9.1 mg.kg-1.day-1. Plasma phenylalanine concentrations confirmed this estimate of requirement. Prior adaptation did not significantly affect overall flux, plasma concentration, or oxidation nor did it affect the requirement estimate. With the assumption that tyrosine can supply two-thirds of the aromatic amino acid requirement, these data suggest that the aromatic amino acid requirement should be 30 mg.kg-1.day-1 and the World Health Organization recommendation of 14 mg.kg-1.day-1 is an underestimate.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 454-454
Author(s):  
Valens Niyigena ◽  
K P Coffey ◽  
W K Coblentz ◽  
D Philipp ◽  
M C Savin ◽  
...  

Abstract Dietary manipulations to include tannins can change the proportion and amounts of N excreted in the urine and feces as well as improve N-use efficiency in ruminants. This study was conducted to investigate effects on animal digestion parameters of adding different proportions of sericea lespedeza hay (SL) to alfalfa silage. Alfalfa was harvested in June 2018 at 75% bloom, chopped, and then packed at 55% moisture into plastic-lined bins and allowed to ensile for 3 months. Alfalfa silage was either offered alone or mixed with 9, 18, or 27% SL on a DM basis. These diets were offered randomly for ad libitum consumption to 16 ewes (41.8 ± 4.61 kg BW) in a randomized complete block design experiment with 2 periods to provide 4 observations per treatment per experimental period, each consisting of a 14-d dietary adaptation period followed by 5 d of total fecal and urine collection. Data were analyzed using PROC MIXED of SAS and orthogonal linear and quadratic trend analyses were tested. Digestibility (%) of DM and OM and digestible DM and OM intake (g/kg BW) decreased linearly (P < 0.05) with increasing SL addition to the diet. Digestibility of NDF and ADF decreased linearly (P < 0.01) with increasing SL, and apparent absorption (%) of N decreased linearly (P < 0.05) with increasing SL in the diet. Urinary N excretions (g/d) tended (P = 0.10) to decrease linearly while fecal N (g/day) tended to increase (P = 0.10) linearly with increasing SL proportion in the diet. In this study, supplementation with sericea lespedeza as a tannin source to alfalfa silage decreased forage digestibility and digestible organic matter intake and did not positively influence nitrogen use. The study was supported in part by USDA-ARS specific cooperative agreement 58-3655-4-052 and by USDA NIFA grant 2018-67019-27804.


2019 ◽  
Vol 59 (10) ◽  
pp. 1858 ◽  
Author(s):  
F. S. Parra ◽  
J. R. Ronchesel ◽  
C. L. Martins ◽  
A. Perdigão ◽  
M. C. S. Pereira ◽  
...  

In the present study, the effects of restricted intake of the final finishing diet as a means of dietary adaptation compared with diets increasing in concentrate content (step-up) over periods of 14 and 21 days on growth performance, carcass characteristics, feeding behaviour and rumen morphometrics of Nellore cattle were evaluated. One hundred and twenty 20 months old Nellore bulls (initial BW = 372.2 kg, s.d. = 21.5 kg) were randomly allocated in 24 pens (n = 5 per pen) and fed for 84 days. The study had a completely randomised design with a 2 × 2 factorial arrangement: adaptation using both 14-day and 21-day step-up and restriction protocols. Each treatment was replicated 6 times. One bull per pen was slaughtered (n = 24) at the end of adaptation period to evaluate rumen morphometrics. The remaining bulls (n = 96) were slaughtered at the end of experimental period. Interactions were observed (P < 0.05) for growth performance, feeding behaviour and rumen morphometrics variables. Overall, no protocol or adaptation length main effect (P > 0.05) was observed for any of the growth rate and carcass traits evaluated, except for hot carcass weight (P = 0.03) and dressing percentage (P = 0.04), where bulls adapted for 14 days had heavier carcasses and increased dressing percentage when compared with cattle adapted for 21 days. Cattle adapted for 21 days had a larger (P = 0.005) rumen wall absorptive surface area at the end of adaptation period than those adapted for 14 days; however, no differences were detected at the end of finishing period. Thus, Nellore yearling bulls could be adapted for 14 days regardless of the protocol.


2019 ◽  
pp. 98-100
Author(s):  
Д. М. Кудайбердиева

Аннотация. В данной статье рассматривается проблема восприятия городской среды студентами из города и сельской местности. Обозначены определения терминов «среда», «пространственная среда», «городская среда». Проведено экспериментальное сравнительное исследование особенностей восприятия города Бишкек городскими и сельскими студентами в количестве 50 человек. Статья содержит результаты проведенного анализа исследования. Выявлены различия и сходства в восприятии города Бишкек у студентов двух групп. В контексте восприятия города изучена неудовлетворенность прошлым и настоящим временем, трудности языкового барьера у студентов из сельской местности. Также было выявлено, что актуальной для студентов обеих групп является потребность в социальных контактах, общении, включенности в социум. Полученные результаты будут иметь пользу в проведении воспитательной работы со студентами из сельской местности, в оказании поддержки им в период адаптации с учетом особенностей восприятия города студентами. Ключевые слова. среда, городская среда, восприятие пространства, городские студенты, сельские студенты, восприятие города Бишкек, неудовлетворенность прошлым и настоящим, языковой барьер, учеба в городе, сходства и различия в восприятии города. Аннотация. Бул макалада шаардык жана айылдан келген студенттердин шаардык чөйрөнү кабыл алуу көйгөйү каралган. «Чөйрө», «мейкиндик чөйрө», «шаардык чөйрө» терминдеринин түшүнүктөрү келтирилген. 50 адамдан турган шаардык жана айылдык студенттердин Бишкек шаарын кабыл алуу өзгөчөлүктөрүнө эксперименталдык салыштырма изилдөө жүргүзүлгөн. Макалада изилдөөнүн анализ жыйынтыктары камтылган. Эки студенттик топторунун Бишкек шаарын кабыл алуусунун айырмачылыктары жана окшоштуктары белгиленген. Шаарды кабыл алуу контекстинде өткөн жана учур чактарга канагаттанбоо, тил барьеринин кыйынчылыктары изилденди. Ошондой эле студенттердин эки тобуна актуалдуу болуп социалдык катнаштарга, баарлашууга, коомго кошулуу муктаждыгы белгиленүүдө. Алынган жыйынтыктар студенттердин шаарды кабыл алуу өзгөчөлүктөрүнө эске алып, айылдан келген студенттерге адаптация убагында колдоо көрсөтүү максатында тарбиялык иштерди жүргүзүүдө жардам берет. Түйүндүү сөздөр. Чөйрө, шаардык чөйрө, мейкиндикти кабыл алуу, шаардык студенттер, айылдык студенттер, Бишкек шаарын кабыл алуу, өткөн жана учур чакка канагаттанбоо, тил барьери, шаарда окуу, шаарды кабыл алуусунун айырмачылыктары жана окшоштуктары. Annotation. This article addresses the problem of perception of the urban environment by students from the city and countryside. The definitions of the terms “environment”, “spatial environment”, and “urban environment” are indicated. An experimental comparative study of the characteristics of the perception of the city of Bishkek by urban and rural students in the amount of 50 people was conducted. The article contains the results of the analysis of the study. The differences and similarities in the perception of the city of Bishkek among students of the two groups are revealed. In the context of the perception of the city, dissatisfaction with the past and the present has been studied, and the difficulties of the language barrier among students from rural areas. It was also revealed that the need for social contacts, communication, inclusion in society is relevant for students of both groups. The results will have the benefit of conducting educational work with students from rural areas, in providing support to them during the adaptation period, taking into account the peculiarities of the perception of the city by students. Кeywords. Environment, urban environment, space perception, urban students, rural students, perception of the city of Bishkek, dissatisfaction with the past and the present, language barrier, studying in the city, similarities and differences in the perception of the city.


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