Suckling behavior, performance, and Kleiber index in calves of different genetic groups under shaded and unshaded environments

Comprehensive analysis of differences in the physiochemical composition of foremilk and hindmilk of grazing indigenous and crossbred dairy goats; implications for growth, milk production and industry

This study was conducted on 90 grazing Hair, Alpine × Hair F1 (AHF1), and Saanen × Hair F1 (SHF1) crossbred goats in three farms located around the Taurus Mountains in Konya, Türkiye. The study investigated variation in milk production, physico-chemical traits of milk fractions (foremilk, hindmilk and total milk), and growth traits. Genotype, parity, offspring sex, birth type, and flock factors significantly influenced milk production and quality traits of milk fractions (P < 0.05 to P < 0.01). Does with male/single offspring produced less milk, but with higher nutrient density (P < 0.05). Hindmilk was 272%, 31% and 61% richer in fat, total solids and energy content than foremilk, respectively (P < 0.001). However, the protein, lactose and solids-non-fat content of hindmilk was on average 7% lower than that of foremilk (P < 0.001). Physico-chemical quality traits of foremilk, hindmilk and total milk had a strong negative correlation with daily milk yield (P < 0.05 to P < 0.001). Live weight and average daily gains (ADG) of kids were influenced by maternal parity, flock, offspring sex and birth type (P < 0.05). The overall Kleiber ratios (KR) from birth to 2 months, birth to 3 months, birth to 6 months and 3 to 6 months of age were 21.0 ± 0.22, 17.1 ± 0.11, 10.5 ± 0.06 and 8.5 ± 0.21 g/kg of metabolic weight, respectively. It was concluded that these findings are critical for milk sampling protocols, offspring growth strategies, product development and precision livestock management.

Performance, body development and ingestive behavior of Nelore and crossbred heifers finished in a grazing system

The aim of this experiment was to evaluate growth, body development and ingestive behavior of Nelore and crossbred heifers. Twenty-two contemporary heifers (eight Nelore, seven Nelore × Angus (½ Angus) and seven Nelore × Pantaneiro (½ Pantaneiro) crosses) were evaluated. The variables evaluated were weight, subcutaneous fat thickness [assessed by ultrasound in the longissimus dorsi (SFT) and biceps femoris (SFTP8)] morphometric measures and ingestive behavior (determined between 7 am and 5 pm). The daily gain differed between the breeds (P < 0.05), being greater for the ½ Pantaneiro than Nelore and equal to ½ Angus at the end of the study. The ½ Angus heifers differed (P < 0.01) from the other breeds for SFT (4.36 mm), with no difference between Nelore (2.77 mm) and ½ Pantaneiro (3.38 mm). The SFTP8 was greater (P < 0.01) (5.36 mm) in ½ Angus heifers than t others crossbreed, and greater in ½ Pantaneiro than in Nelore (4.28 vs 3.29 mm). The heart girth and rump width between the ilia were larger (P < 0.01) for the ½ Angus than ½ Pantaneiro and Nelore (169 cm; 41.6 cm, respectively). Substernal height was greatest (P < 0.01) for the Nelore (69.1 cm), reflecting the greater anterior and posterior height. The ½ Angus spent the longest time (P < 0.05) walking and less time grazing. Idleness also differed (P < 0.05) throughout the day. Crossbred heifers exhibited better performance and development than Nelore. The grazing pattern of ½ Pantaneiro heifers was identical to Nelore, but walked less, gained more weight, and exhibited better carcass finishing.