2014, Number 3
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AbanicoVet 2014; 4 (3)
Estrus distribution in hair ewes mated in November-December under controlled conditions in northern Mexico
Jaramillo-López E, Rubio-Tabares E, Molinar-Holguin F, Itza-Ortíz M, Plasencia-Díaz R, Martínez-Vela A
Language: English
References: 11
Page: 25-30
PDF size: 475.95 Kb.
ABSTRACT
An experiment with hair ewes was carried out in Northern Mexico to determine the estrus distribution after ram introduction to the herd, the effects of animal live weight (LW) on estrus distribution (ED); and the effects of body condition (BC) on estrus distribution (ED) respectively. The experiment was conducted at the El Pénsil Sheep Farm in Chihuahua, Mexico. Two hundred and sixteen ewes and nine rams were used for this experiment. Animals age range was 2.5±0.168 years, animal live weight (LW) of 32.07±0.417 kg, and body condition (BC) ranking score of 3.26±0.047, in a scale 1 to 5. Animals were grazed on pastures with a mix of Bermuda grass and alfalfa for 8 hours a day. On this experiment, total of nine stallions Kathadin, Pelibuey and Black Belly breeds were used. The experiment was conducted between November 19 and December 16, 2011. Descriptive statistics were used to analyze the data. The results indicated that 41% of the ewes reached an estrus between the 6th and 11th day after the introduction of the rams. The highest percentage of estrus (52%) occurred in ewes with a LW between 30 and 40 kilograms; and a BC between 3 and 3.5. All ewes reached an estrus 18 days after introduction of the rams to the herd.
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