The objective of the current study was to evaluate the current status of heifer rearing under typical Mediterranean conditions. Data were collected from 8 dairy farms in the region of Thessaly and Macedonia (Greece) during a 1-day visit. Records on reproduction performance for all cows and heifers present in the herd were obtained by the farmer and used to determine time of first service (T1stSer), services/heifer and time of first calving (T1stCal). Depending on heifer grouping of the farms, 15-20% of heifers in all age groups and older cows were taped measured to estimate body weight (BW). This allowed the determination of average daily gain (ADG) in different ages. Moreover, the mature BW of the cows in each herd was estimated and used to evaluate growth targets. Total mixed ration (TMR) offered to heifers was recorded and feed samples (TMR and ingredients) were collected and chemically analysed for nutrient composition. Based on cows mature BW, and 14 and 24 months for T1stSer and T1stCal, respectively, growth targets for heifers were estimated in each farm. The diets were evaluated with the Cornell Net Carbohydrate and Protein System (CNCPS 6.5). It was found that T1stSer and T1stCal was 15.83±1.96 and 25.83±2.53 months, respectively and pregnancy was achieved with 1.55±1.04) services/heifer. Heifer BW at T1stSer and T1stCal was 416 and 668 kg, respectively that was within the targets (404 and 625 for T1stSer and T1stCal, respectively) but achieved with a delay of 1.83 months. Our analysis suggested that T1stSer is the most critical point where heifers need to meet higher ADG. In all farms and heifer growth stages Metabolizable Energy (ME) was the first limiting factor and Metabolizable Protein (MP) was supplied in excess (up to 140% of requirements for older heifers). Overfeeding crude protein increased feeding cost from 116 to 236 €/heifer depending on protein source
Evaluation of growth and reproduction performance of replacement dairy heifers / Plomaritou, A.; Hanlon, M. E.; Gatsas, K.; Pitino, R.; Tremmas, K.; Karatosidi, L.; Righi, F.; Foskolos, A.. - STAMPA. - 27:(2021), pp. 401-401. (Intervento presentato al convegno 72nd Annual Meeting of the European Federation of Animal Science tenutosi a Davos, Switzerland nel 30th August-3rdSeptember) [10.3920/978-90-8686-918-3].
Evaluation of growth and reproduction performance of replacement dairy heifers
R. Pitino;F. Righi;
2021-01-01
Abstract
The objective of the current study was to evaluate the current status of heifer rearing under typical Mediterranean conditions. Data were collected from 8 dairy farms in the region of Thessaly and Macedonia (Greece) during a 1-day visit. Records on reproduction performance for all cows and heifers present in the herd were obtained by the farmer and used to determine time of first service (T1stSer), services/heifer and time of first calving (T1stCal). Depending on heifer grouping of the farms, 15-20% of heifers in all age groups and older cows were taped measured to estimate body weight (BW). This allowed the determination of average daily gain (ADG) in different ages. Moreover, the mature BW of the cows in each herd was estimated and used to evaluate growth targets. Total mixed ration (TMR) offered to heifers was recorded and feed samples (TMR and ingredients) were collected and chemically analysed for nutrient composition. Based on cows mature BW, and 14 and 24 months for T1stSer and T1stCal, respectively, growth targets for heifers were estimated in each farm. The diets were evaluated with the Cornell Net Carbohydrate and Protein System (CNCPS 6.5). It was found that T1stSer and T1stCal was 15.83±1.96 and 25.83±2.53 months, respectively and pregnancy was achieved with 1.55±1.04) services/heifer. Heifer BW at T1stSer and T1stCal was 416 and 668 kg, respectively that was within the targets (404 and 625 for T1stSer and T1stCal, respectively) but achieved with a delay of 1.83 months. Our analysis suggested that T1stSer is the most critical point where heifers need to meet higher ADG. In all farms and heifer growth stages Metabolizable Energy (ME) was the first limiting factor and Metabolizable Protein (MP) was supplied in excess (up to 140% of requirements for older heifers). Overfeeding crude protein increased feeding cost from 116 to 236 €/heifer depending on protein sourceI documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
