This study investigates the influence of internal factors on growth dynamics in four Cyprinus carpio varieties, three Romanian strains (Frăsinet, Ineu, and Podu Iloaiei) and the Koi variety. Fish were measured for total length, maximum height, and weight at four ontogenic stages, namely 7 days post-hatch, 3 months (0⁺), 18 months old (1⁺), and 36 months (2⁺). Weight Gain (WG), Specific Growth Rate (SGR), Relative Growth Rate (RGR), Fulton’s condition factor, and the profile index were calculated and analyzed. Results revealed significant intervariety differences in growth performance and physiological condition across life stages. At the 2⁺ stage, Podu Iloaiei exhibited the highest WG (849.73 ± 4.09 g), while Koi showed the lowest (403.99 ± 14.21 g). Koi demonstrated a unique growth pattern, with the highest SGR (0.18 ± 0.00% day⁻¹) and RGR (0.98 ± 0.05 g day⁻¹) at the 2⁺ stage. Fulton’s condition factor varied markedly, with Frăsinet showing the highest value at 7 days post-hatch (149.57 ± 17.485) and Koi the lowest at the 1⁺ stage (0.63 ± 0.011). The profile index decreased with age in all varieties, with Podu Iloaiei showing the most dramatic change from 4.22 ± 0.149 at 7 days to 2.18 ± 0.004 at 2⁺. These findings highlight the complex interplay between genetic and developmental factors in carp varieties, offering new insights for tailored breeding programs and aquaculture practices.

The absence of standardized reference values for wild rodent species underscores the need for comprehensive hematological and biochemical profiles. This study established robust reference intervals (RIs) for Myocastor coypus raised in captivity, analyzing 30 nutrias (10 males, 10 females, and 10 juveniles) at a private farm in northeastern Romania. Leukocyte (WBC) counts averaged 11.85 (10³/µL) in males, 10.51 (10³/µL) in females, and 11.63 (10³/µL) in juveniles, indicating a consistent immune response. Hemoglobin was 11.81 g/dL in males, 11.97 g/dL in females, and 15.42 g/dL in juveniles, with hematocrit levels around 45%. Juveniles displayed higher MCH (38.59 pg) and MCHC (38.58 g/dL), reflecting growth-related adaptations. Platelet counts were lower in adults. Biochemical findings showed lower cholesterol (14.89 mg/dL) and higher glucose (236.26 mg/dL) in juveniles, indicating intense energy metabolism. Total proteins were significantly elevated in juveniles (33.17 g/dL). Creatinine and uric acid levels were higher in adults, although calcium exceeded reference ranges in males (12.04 mg/dL). Hepatic enzyme ALT was higher in males. These findings establish baseline health parameters for captive nutrias, aiding in monitoring and improving rearing practices.

The global aquaculture industry produces 91 million tons annually, yet achieving sustainable growth optimization remains constrained by incomplete understanding of regulatory system integration, polyploid genomic complexity, and disconnected molecular-environmental approaches. This systematic review synthesizes 180 peer-reviewed articles (1992–2025) from four databases, revealing that growth regulation operates through integrated multi-level networks: the GH-IGF axis, TGF-β/myostatin signaling, and epigenetic mechanisms responding dynamically to environmental inputs. Research acceleration is evident, with 52.2% of studies published during 2020–2025. Whole-genome duplication events created expanded gene repertoires enabling sophisticated regulatory control while presenting breeding challenges in polyploid species. CRISPR-Cas9 myostatin knockout achieves 15–30% growth enhancement, though practical implementation faces regulatory and economic barriers. DNA methylation and microRNAs enable environmental adaptation and transgenerational trait inheritance, offering complementary approaches to conventional breeding. Climate-resilient strain development requires integrating polyploid breeding methodologies, multi-omics phenotyping platforms, and validated epigenetic markers. Sustainable aquaculture intensification through precision genetics demands coordinated infrastructure development, harmonized regulatory frameworks, and international collaboration to address food security while adapting to climate change. This synthesis establishes research priorities bridging molecular mechanisms with practical applications for sustainable production enhancement.

This study evaluated the relationship between age at first mating and gestation length, body development, reproductive performance and kid growth in Carpathian goats raised under a traditional production system. A total of 150 females were assigned to three groups according to age at first mating: L1 (7–8 months), L2 (12–13 months) and L3 (17–18 months). A reference group of 50 adult females was used to assess body development. Mean gestation length ranged from 150.74 to 151.55 days, without significant differences among groups (p > 0.05). During the first breeding season, mean body weight in L1, L2 and L3 represented 54.2%, 66.0% and 75.3% of adult female body weight, respectively. By 2024, these proportions had reached 91.9%, 96.3% and 98.1. Kidding rates differed significantly among groups (p < 0.001), with values of 70% in L1, 76% in L2 and 100% in L3, while live-born kids represented 78.9%, 88.9% and 95.3% of all kids born, respectively. L1 females therefore had the lowest kidding rate and the highest proportion of stillborn kids (21.1%), compared with 11.1% in L2 and 4.7% in L3. Single-born kids maintained higher body weights than twin-born kids until 90 days of age. The results indicate that first mating at 7–8 months of age was biologically possible in Carpathian females, but females in this group had a lower kidding rate and a lower level of body development than those in the more developed groups. These findings indicate that breeding readiness should be evaluated in relation to both age and body development, particularly body weight at first mating.

The aim of this paper is to predict the improvement value by the BLUP methodology - the Sire Model, of some bulls used to inseminate females exploited in conditions of a farm located in N-W Moldova, Romania. After comparing the main productive characters between ancestry (MT – 5260.22 KG milk) and offspring it was observed that the descendants have a higher average production in LN1, of 5470 kg milk in LN1 and a lower production in LN2, about 5210.14 kg. Even if in the population the value of h2 is 0.64 females do not phenotypically express their genetic potential. We can say that their performances are influenced by environmental factors that primarily relate to the growth technology, fee-ding and the climate in which they grow. Among the bulls for which the estimate of improvement value was made, the one with registration number 53791 has the best improvement value of 451.1825 kg for milk production. This male is a breeder for other traits as well.