Effects of photoperiod and pair-feeding on lactation of cows fed corn or barley grain in total mixed rations.
J Dairy Sci
; 72(11): 2999-3005, 1989 Nov.
Article
en En
| MEDLINE
| ID: mdl-2625490
ABSTRACT
Effects of photoperiod and type of grain were assessed using 47 cows (wk 1; 59.5 d of lactation) exposed daily to 16 h of light (long day) and fed randomly one of two diets containing an equal amount of cracked corn or rolled barley. During wk 5, cows were assigned within each diet to long day and ad libitum feeding, short day (8 h of light 2 h of dark 2 h of light 12 h of dark) and ad libitum feeding, or long day and ad libitum feeding (wk 5 to 8) followed by pair feeding with short day cows between wk 9 and 16. Milk composition was not affected by treatments. Between wk 9 and 16, long day cows fed for ad libitum consumption or pair fed produced 5 to 11% more milk than cows exposed to short day; feed intake of long day cows fed for ad libitum consumption was greater than short short day and long day cows pair fed cows. Milk yield and total feed intake were not affected by type of grain in the diet. In conclusion, long day photoperiod increased milk yield and feed intake.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Lactancia
/
Bovinos
/
Ritmo Circadiano
/
Luz
/
Alimentación Animal
Límite:
Animals
/
Pregnancy
Idioma:
En
Revista:
J Dairy Sci
Año:
1989
Tipo del documento:
Article
País de afiliación:
Canadá