Heterosis and direct effects for Charolais-sired calf weight and growth, cow weight and weight change, and ratios of cow and calf weights and weight changes across warm season lactation in Romosinuano, Angus, and F1 cows in Arkansas1

Abstract

The use of Brahman in cow-calf production offers some adaptation to the harsh characteristics of endophyte-infected tall fescue. Criollo breeds, such as the Romosinuano, may have similar adaptation. The objectives were to estimate genetic effects in Romosinuano, Angus, and crossbred cows for their weights, weights of their calves, and ratios (calf weight:cow weight and cow weight change:calf weight gain) across lactation and to assess the influence of forage on traits and estimates. Cows ( = 91) were bred to Charolais bulls after their second parity. Calves ( = 214) were born from 2006 to 2009. Cows and calves were weighed in early (April and June), mid- (July), and late lactation (August and October). Animal was a random effect in analyses of calf data; sire was random in analyses of cow records and ratios. Fixed effects investigated included calf age, calf sex, cow age-year combinations, sire breed of cow, dam breed of cow, and interactions. Subsequent analyses evaluated the effect of forage grazed: endophyte-free or endophyte-infected tall fescue. Estimates of maternal heterosis for calf weight ranged from 9.3 ± 4.3 to 15.4 ± 5.7 kg from mid-lactation through weaning ( < 0.05). Romosinuano direct effects (of the cow) were -6.8 ± 3.0 and -8.9 ± 4.2 kg for weights recorded in April and June. Calf weights and weight gains from birth were greater ( < 0.05) for calves of cows grazing endophyte-free tall fescue except in mid-summer. Cow weight change from April to each time was negative for Angus cows and lower ( < 0.05) than other groups. Cows grazing endophyte-free tall fescue were heavier ( < 0.05) at all times but had more weight loss in late lactation. Angus cows had the lowest ( < 0.05) ratios (negative) of cow weight change:calf weight gain, indicating an energy-deficit condition. Cows grazing endophyte-free tall fescue had more negative ( < 0.05) values for this trait but not in early lactation ( < 0.05). Estimates of heterosis ranged from 12.8 ± 9.5 to 28.6 ± 9.4 kg for cow weight, 7.9 ± 3.0 to 15.8 ± 5.0 kg for cow weight change, and 0.07 ± 0.03 to 0.27 ± 0.1 for cow weight change:calf weight gain. Direct Romosinuano effects ranged from 14.8 ± 4.2 to 49.8 ± 7.7 kg for cow weight change and 0.2 ± 0.04 to 0.51 ± 0.14 for cow weight change:calf weight gain. The adaptive ability of Romosinuano in temperate fescue regions may be favorable with respect to relative cow and calf weight but may be a consequence of lower milk-producing ability.

Genomic Regions Associated with Feed Efficiency Indicator Traits in an Experimental Nellore Cattle Population

“…Bolormaa et al [ 11 ] also reported higher heritability estimates for RFI (0.36), in a study with nine herds of Bos Taurus , Bos indicus , and crossbreeds. Also, Silva et al [ 35 ] reported similar heritability estimates for ADG (0.39±0.08) and DMI (0.43±0.08) in a study using the same experimental population. The results of this study pointed out that there is genetic variability in selecting for feed efficiency indicator traits in Nellore cattle.…”

Activity of Zearalenone in the Porcine Intestinal Tract

“…Mucus glycoproteins are least abundant in the duodenum and jejunum, which contributes the movement of digesta across intestinal walls [ 51 ] and increases its availability. Most carbohydrates are simultaneously absorbed in the proximal part of the small intestine [ 104 ], which significantly contributes to the absorption, accumulation and, probably, biotransformation of mycotoxins in enterocytes [ 81 , 105 ]. Published data relating to those processes and the involved intestinal segments are incomplete and often contradictory.…”

Evaluation of the Romosinuano cattle population structure in Mexico using pedigree analysis

“…Several breeders in the Mexican tropics have used Romosinuano due to ease of management, longevity (Carroll et al, 2011;, fertility (Riley et al, 2007), tolerance to heat, humidity (Scharf et al, 2010), and to the toxic effects of endophytes commonly present in tall fescue (Riley et al, 2016). The Asociación Mexicana de Criadores de Ganado Romosinuano y Lechero Tropical (AMCROLET) was established in 1998 (De Alba, 2011), and it is responsible for the herdbook and the performance records.…”