scholarly journals The Relation Between the Responses of Wool Growth and Body Weight to Changes in Feed Intake

1962 ◽  
Vol 15 (4) ◽  
pp. 720 ◽  
Author(s):  
KA Ferguson
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Feed Intake ◽  
Weight Change ◽  
Productive Efficiency ◽  
Intake Rate ◽  
Body Weight Change ◽  
Growth Responses ◽  
Wool Growth

The wool growth responses to changes in feed intake are related to the changes produced in body weight. The relation is expressed by the equation W = Ei-kG, where W = wool growth rate, i = feed intake rate, G = rate of body weight change, and E and k are constants. The ratio of E to k in sheep of different productive efficiency was found to be constant.

The description and analysis of wool growth

1977 ◽  
Vol 28 (4) ◽  
pp. 737 ◽  
Author(s):  
BN Nagorcka
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Linear Regression ◽  
Least Squares ◽  
Ordinary Least Squares ◽  
Time Dependent ◽  
Recursive Least Squares ◽  
Growth Time ◽  
Body Weight Change ◽  
Wool Growth

Analyses of experimental estimates of the wool growth rate as a function of intake have previously been based on time-independent equations and linear regression with ordinary least squares. Some of these results are reanalysed with the assumption that the sheep is a dynamic system; hence a time-dependent description of wool growth is proposed. A recursive least squares technique has been used, and the results demonstrate that there is a 3½ week lag between intake and wool growth. Time-independent descriptions have not taken account of this and have led to the misconception that efficiency is a function of body weight change.

N-[5-(4-Aminophenoxy)pentyl]phthalimide as a potential defleecing agent and its effect on wool growth

1980 ◽  
Vol 31 (4) ◽  
pp. 791
Author(s):  
DA Tunks ◽  
RDG Rigby ◽  
AM Downes ◽  
JA Lamberton ◽  
BA Panaretto ◽  
...  
Keyword(s):  
Growth Rate ◽  
Body Weight ◽  
Oral Dose ◽  
Feed Intake ◽  
Merino Sheep ◽  
Dose Rates ◽  
Wool Growth

Merino sheep, offered feed at two levels of intake, were given an oral dose of N-[5-(4-am1nophenoxy)- pentyllphthahmide at rates varying over 100-800 mg/kg body weight. Consistent defleecing was obtained at dose rates of 400 nig/kg and above. Feed intake did not Influence defleecing activity. lntravenous infusion of smaller amounts also allowed defleecing. Wool growth rate following dosing was not affected by a dose of 100 mg/kg, but doses of 200 and 400 mg/kg caused depressions of c. 15 and c. 70% respectively in the rate of wool growth in the 2 weeks after dosing. Blindness was observed In one sheep dosed at 400 mg/kg and In all sheep dosed at higher rates

scholarly journals Body size and its effects on productive efficiency of cows with predominant Nellore genetic composition

2018 ◽  
Vol 40 (1) ◽  
pp. 42532
Author(s):  
Gustavo Duarte Farias ◽  
Liliane Cerdótes ◽  
João Restle ◽  
Leonir Luiz Pascoal ◽  
Pablo Tavares Costa ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Reproductive Performance ◽  
Weight Change ◽  
Productive Efficiency ◽  
Lactation Period ◽  
Body Weight Change ◽  
Genetic Composition ◽  
Production Index ◽  
Total Gain

 This study was developed to evaluate productive efficiency during the lactation period of cows with predominant Nellore genetic composition based on their body size. Cows were divided into the following categories: light (≤ 316 kg), moderate (≥ 317 and ≤ 400 kg), or heavy (≥ 401 kg). Body weight change and total gain from birth to 210 days of age of calves born from heavy cows (0.155±0.03 and 111.6±5.1 kg) were higher than those of calves born from light (0.064±0.03 and 91.0±4.3 kg) and moderate (0.144±0.03 and 97.7±4.0 kg) cows. Calf production index differed (p < 0.05) with the herd of heavy cows (93.5±3.2 kg), producing 57.4 and 19.7% more kilograms of calf than light (59.4±2.7 kg) and moderate (78.1±2.4 kg) cows, respectively. Heavy Nellore cows produce heavier calves and have a better reproductive performance, which lead to a better calf production index. However, they require a larger area for the same herbage allowance. Calves born from heavier Nellore cows gain more weight from birth to 210 days of age and are heavier from 210 to 270 days of age. 

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